Chapter 52. Cardiovascular Disorders. Will Obs

 Cardiovascular Disorders

BS. Nguyễn Hồng Anh

In an analysis o maternal mortality in the United States

between 2011 and 2013, deaths related to hemorrhage, hypertensive disorders, and embolism showed declining rates. In

contrast, deaths attributable to cardiovascular diseases are rising and are responsible or one ourth o all pregnancy-related

mortalities (Creanga, 2017; Petersen, 2019). Recent development o state-level maternal mortality review committees have

emphasized this issue and highlighted the relatively protracted

timeline o illness. Up to a year ater delivery, cardiac events

were among the leading causes o death or women in exas

in 2013 (exas Maternal Morbidity ask Force, 2020). Tese

disorders account also or signicant maternal morbidity and

are a common reason or intensive care unit admissions (Small,

2012).

Cardiovascular disease complicates 1 to 4 percent o pregnancies in the United States (American College o Obstetricians and Gynecologists, 2019). Te increasing prevalence is

likely multiactorial and includes the higher rates o obesity,

hypertension, and diabetes (Klingberg, 2017). According to the

National Center or Health Statistics, almost hal o adults aged

20 and older have at least one risk actor or cardiovascular

disease (Fryar, 2012). Another related reason is delayed childbearing. Last, as discussed subsequently (p. 927), an increasing number o women with congenital heart disease are now

becoming pregnant.

Te importance o heart disease and its adverse eect on

pregnancy morbidity and mortality led the American College

o Obstetricians and Gynecologists to create a ask Force on

Pregnancy and Heart Disease. Its purpose is to emphasize the

prevalence and eect o heart disease in pregnancy, provide

guidance or risk actor identication, outline common cardiovascular disorders, provide recommendations or management,

and develop a comprehensive interpregnancy plan. Multidisciplinary care is essential (Quinones, 2021).

PHYSIOLOGICAL CONSIDERATIONS

IN PREGNANCY

■ Cardiovascular Physiology

Te marked pregnancy-induced anatomical and unctional

changes in cardiac physiology can have a proound, negative

eect on underlying heart disease. Tese changes are discussed

in detail in Chapter 4 (p. 62), and some are listed in Table 52-1

(Clark, 1989). Importantly, cardiac output increases approximately 40 percent during pregnancy. Almost hal o this total

takes place by 8 weeks’ gestation and is maximal by midpregnancy (Capeless, 1989). Tis early rise stems rom augmented

stroke volume, which results rom lowered vascular resistance.

Later in pregnancy, resting pulse and stroke volume are even

higher because o greater end-diastolic ventricular volume that

results rom augmented pregnancy blood volume. Tese adaptations are even more proound in multietal pregnancies (Ghi,

2019). Intrinsic let ventricular contractility does not change,

and thus normal let ventricular unction is maintained during

pregnancy. Namely, pregnancy is not characterized by hyperdynamic unction or a high cardiac-output state.

Women with underlying cardiac disease may not always

accommodate these changes, and ventricular dysunction leads

to cardiogenic heart ailure. A ew women with severe cardiac

dysunction can experience evidence o heart ailure beore midpregnancy. In others, heart ailure may develop ater 28 weeks’

gestation, when pregnancy-induced hypervolemia and cardiac

output reach their maximum. In most, however, heart ailure

develops peripartum, when labor, delivery, and several common

obstetrical conditions add undue cardiac burdens. Some o the

latter include preeclampsia, hemorrhage and anemia, and sepsis.

■ Ventricular Function in Pregnancy

Ventricular volumes and mass accrue to accommodate pregnancy-induced hypervolemia. Tis is reected by greater

end-systolic and end-diastolic dimensions. At the same time,

however, septal thickness and ejection raction are unchanged.

Tis is because these alterations are accompanied by substantive ventricular remodeling—plasticity—which is characterized

by eccentric expansion o let-ventricular mass that averages 30

to 35 percent near term. All o these adaptations return to prepregnancy values within a ew months postpartum.

Certainly or clinical purposes, ventricular unction during

pregnancy is normal as estimated by the Braunwald ventricular unction graph (Fig. 4-9, p. 63). Tus, or given lling pressures, cardiac output is appropriate and allows eudynamic cardiac

unction during pregnancy. Esoteric changes in pregnancyrelated cardiac physiology continue to be claried. In nonpregnant subjects with a normal heart who sustain a high-output

state, the let ventricle undergoes longitudinal remodeling, and

echocardiographic unctional indices o its deormation show

normal values. In pregnancy, the ventricle instead undergoes

spherical remodeling, and the calculated indices that measure longitudinal deormation are depressed. Tus, normal nonpregnant

indices are likely less accurate when used to assess unction in

pregnant women because they do not account or the spherical

remodeling (Savu, 2012; Stewart, 2016).

Adjusting or these geometrical changes, Melchiorre and

coworkers (2016) studied normal cardiac echocardiographic

ndings in 559 nulliparas at our points during pregnancy

and again at 1 year postpartum. At term, signicant chamber

diastolic dysunction was present in 18 percent and impaired

myocardial relaxation was evident in 28 percent o the women.

Also, a signicant proportion o women demonstrated a drop

in stroke volume index and a tendency toward eccentric remodeling. Tese ndings suggest cardiovascular maladaptation to

the expanded volume demands in a substantial proportion o

apparently normal pregnancies. Signicant dyspnea at rest was

reported by 7.4 percent o the women at term, most o whom

had chamber diastolic dysunction. Cardiac unction and all

signs o dyspnea ully recovered at 1 year postpartum.

Cardiac magnetic resonance (MR) imaging increasingly is

used to evaluate cardiac structure and unction. Stewart and

associates (2016) perormed cardiac MR imaging studies in

23 women longitudinally across pregnancy and at 12 weeks postpartum. Compared with studies perormed at 12 to 16 weeks’

gestation, let ventricular mass grew signicantly or both normalweight and overweight women. Te calculated geometrical ratio

o let ventricular mass to let ventricular end-diastolic volume

demonstrated concentric remodeling throughout gestation,

which resolved by 12 weeks’ postpartum. Te right ventricle

also undergoes remodeling (Martin, 2017). Tese observations

likely mean that pregnancy causes a mixture o eccentric and

concentric ventricular remodeling.

DIAGNOSIS OF HEART DISEASE

Te physiological adaptations o normal pregnancy can induce

symptoms and alter clinical ndings that may conound the

diagnosis o heart disease. For example, in normal pregnancy,

unctional systolic heart murmurs are common, respiratory eort is accentuated, edema requently accrues in lower

extremities ater midpregnancy, and atigue and exercise intolerance oten develop. Some systolic ow murmurs can be loud,

and normal changes in the various heart sounds depicted in

Figure 52-1 may erroneously suggest cardiac disease. In contrast, clinical ndings that are more likely to suggest heart disease are listed in Table 52-2.

■ Diagnostic Studies

Noninvasive cardiovascular studies such as electrocardiography,

chest radiography, and echocardiography will provide the data

necessary or cardiac unctional evaluation in most women.

In the electrocardiogram (ECG), an average 15-degree letaxis deviation is ound as the diaphragm is elevated in advancing pregnancy. Other ndings are described in Figure 52-2

FIGURE 52-1 Normal cardiac examination findings in the pregnant woman. S1 = first sound; M1 = mitral first sound; S2 = second sound;

P2 = pulmonary second sound. (Data from Gei, 2001; Hytten, 1991.)

TABLE 52-2. Clinical Indicators of Heart Disease

During Pregnancy

Symptoms

Progressive dyspnea or orthopnea

Nocturnal cough

Hemoptysis

Syncope

Chest pain

Clinical Findings

Cyanosis

Clubbing of fingers

Persistent neck vein distention

Systolic murmur grade 3/6 or greater

Diastolic murmur

Cardiomegaly

Persistent tachycardia and/or arrhythmia

Persistent split second sound

Fourth heart sound

Criteria for pulmonary hypertension

Q wave in

lead DIII

Leftward deviation of the mean QRS axis

+90°

aVF

+90°

aVF

aVF aVF

0° DI 0° DI

DI DI

Reduction in

PR interval

Increase

in HR

FIGURE 52-2 Normal electrocardiograph (ECG) adaptations during

pregnancy, including a reduced mean PR interval, increased heart

rate, left axis deviation, inverted or flattened T waves, and a Q wave in

lead DIII. HR = heart rate. (Reproduced with permission from Angeli F,

Angeli E, Verdecchia P: Electrocardiographic changes in hypertensive

disorders of pregnancy, Hypertens Res 2014 Nov;37(11):973–975.)

(Angeli, 2014). Pregnancy does not alter voltage ndings.

Atrial and ventricular premature contractions are relatively

requent.

With radiography, anteroposterior (AP) and lateral chest

radiographs are useul, and when a lead apron shield is used,

etal radiation exposure is minimal. Gross cardiomegaly can

usually be excluded, but slight heart enlargement is poorly

detected because the heart silhouette normally is larger in pregnancy. Tis is accentuated urther with a portable posterioranterior chest radiograph.

Echocardiography is now widely used and permits accurate

diagnosis o most heart diseases during pregnancy. Some normal pregnancy-induced changes include a small increase in

the dimensions o all cardiac chambers, a slight but signicant

growth in let ventricular mass, and greater tricuspid and mitral

valve regurgitation (Grewal, 2014). O note, systolic unction

normally does not change and ejection raction is preserved.

Late geometric changes such as interventricular septum dimension (IVd) are likely to be abnormal beore changes in ejection

raction. Savu (2012) and Vitarelli (2011) and their colleagues

have provided normal echocardiographic parameters or pregnancy, which are listed in the Appendix (p. 1233). In some

situations, such as complex congenital heart disease, transesophageal echocardiography may be useul.

Cardiovascular MR imaging, compared with echocardiography, is associated with higher reproducibility and is less hindered by ventricular geometry and body habitus. It is useul or

assessment o the right ventricle and visualization o congenital

heart lesions and myocarditis (Herrey, 2019; Martin, 2017).

Ducas and coworkers (2014) have published normal reerence

values or pregnancy.

Exercise stress testing is an objective assessment o maternal unctional capacity. It is also useul to diagnose exerciseinduced arrhythmias. Stress testing can be perormed in women

with known heart disease prior to pregnancy or, i necessary, in

the asymptomatic pregnant women (Regitz-Zagrosek, 2018).

Dennis and associates (2019) have described ndings in normal

pregnant women using the 6-minute walk test.

Myocardial perusion studies using albumin or red cells

tagged with technetium-99m are rarely needed during pregnancy to evaluate ventricular unction. Tat said, the estimated etal radiation exposure rom nuclear medicine studies

o myocardial perusion is negligible (Chap. 49, p. 875). Cardiac catheterization with limited uoroscopy time also is sae

to perorm. During coronary angiography, the mean radiation exposure to the unshielded abdomen is 1.5 mGy, and

less than 20 percent o this reaches the etus (Regitz-Zagrosek,

2018). Shortening the uoroscopic time may help to minimize

radiation exposure (Raman, 2015; uzcu, 2015). In women

with clear indications, any minimal theoretical etal risk is

outweighed by maternal benets, and such studies should be

perormed as indicated.

■ Functional Classification of Heart Disease

Pregnancy is a stress test o cardiovascular reserve. However,

no clinically applicable test accurately measures unctional cardiac capacity. Te clinical classication o the New York Heart

Association (NYHA) is based on past and present disability and

is uninuenced by physical signs:

• Class I. Uncompromised—no limitation o physical activity:

Tese women do not have symptoms o cardiac insufciency

or experience anginal pain.

• Class II. Slight limitation o physical activity: Tese women

are comortable at rest, but with ordinary physical activity,

discomort in the orm o excessive atigue, palpitation, dyspnea, or anginal pain results.

• Class III. Marked limitation o physical activity: Tese women

are comortable at rest, but less than ordinary activity causes

excessive atigue, palpitation, dyspnea, or anginal pain.

• Class IV. Severely compromised—inability to perorm any physical activity without discomort: Symptoms o cardiac insu-

ciency or angina may develop even at rest. I any physical

activity is undertaken, discomort is increased.

At least our predictive systems detect and classiy heart

disease in pregnant women. Tese include CARPREG I and

II, ZAHARA, and the World Health Organization (WHO)

system (Wole, 2019). O these, the most comprehensive risk

stratication system is the modied WHO Risk Classication

o Cardiovascular Disease and Pregnancy (Table 52-3). Tis

classication system was validated in an international cohort o

2742 pregnant women with heart disease (van Hagen, 2016).

It is especially useul or assessing maternal risk and or preconceptional counseling. Lu (2015) and Pijuan-Domènech (2015)

and their colleagues concluded that the modied WHO classication provides the greatest predictive accuracy or cardiac

complications during pregnancy.

GENERAL PREGNANCY CONSIDERATIONS

■ Preconceptional Counseling

Women with severe heart disease will benet immensely rom

counseling beore pregnancy, and they usually are reerred or

maternal-etal medicine or cardiology consultation (Clark,

2012; Wole, 2019). Optimizing cardiac unction to mitigate

complications during pregnancy is the goal. Maternal mortality

rates generally correlate directly with unctional classication,

however, this relationship may change as pregnancy progresses.

Siu and coworkers (2001b) observed signicant worsening o

NYHA class in 4.4 percent o 579 pregnancies in which the

baseline class was I or II.

As described later, some women have lie-threatening cardiac abnormalities that can be reversed by corrective surgery,

and subsequent pregnancy becomes less dangerous. In other

cases, such as women with mechanical valves taking wararin,

etal teratogenic concerns predominate. Last, because many

congenital heart lesions are inherited as polygenic characteristics, some women with congenital heart lesions give birth to

similarly aected neonates. Tis risk varies widely based on the

specic abnormality (Table 52-4) (Lupton, 2002).

Risk Factors

According to the American College o Obstetricians and

Gynecologists (2019), our maternal risk actors are linked to

TABLE 52-3. World Health Organization (WHO) Risk Classification of Cardiovascular Disease and Pregnancy with

Management Recommendations

Risk Category Associated Conditions

WHO 1—Morbidity or mortality risk no higher than

general population

Uncomplicated, small, or mild:

Pulmonary stenosis

Patent ductus arteriosus

Mitral valve prolapse with no more than trivial mitral regurgitation

Successfully repaired simple lesions:

Ostium secundum atrial septal defect

Ventricular septal defect

Patent ductus arteriosus

Total anomalous pulmonary venous drainage

Isolated ventricular extrasystoles and atrial ectopic beats

• Cardiology consultation once or twice during pregnancy. Local hospital care suitable

WHO 2—Small increase in risk of maternal mortality

and moderate increase in morbidity risk

If otherwise uncomplicated:

Unoperated atrial or ventricular septal defect

Repaired Fallot tetralogy

Most arrhythmias

Turner syndrome without aortic dilation

• Cardiology consultation each trimester. Local hospital care suitable

WHO 2 or 3—Intermediate increase in maternal

mortality risk and moderate to severe rise in

morbidity risk

Mild left ventricular impairment

Hypertrophic cardiomyopathy

Native or tissue disease not considered WHO 1 or 4

Marfan syndrome without aortic dilation

Repaired coarctation

Prior heart transplantation

• Cardiology consultation bimonthly. Care at referral hospital

WHO 3—Significantly increased risk of maternal

mortality and severe increase in morbidity risk

Mechanical valve

Systemic right ventricle

Post-Fontan operation

Unrepaired cyanotic heart disease

Other complex congenital heart disease

Moderate left ventricular impairment

Prior peripartum cardiomyopathy with no residual effect

Moderate mitral stenosis

Severe asymptomatic aortic stenosis

Moderate aortic dilation (40–50 mm)

Ventricular tachycardia

• Cardiology consultation monthly or bimonthly. Care at tertiary-care hospital

WHO 4—Very high risk of maternal mortality or

severe morbidity; pregnancy contraindicated

and termination discussed

Pulmonary arterial hypertension

Severe systemic ventricular dysfunction (NYHA III–IV or LVEF <30%)

Prior peripartum cardiomyopathy with residual effects

Severe left heart obstruction

Severe aortic dilation

Severe coarctation

Fontan procedure with residual complications

• Pregnancy contraindicated

• If pregnancy occurs, cardiology consultation monthly. Care at tertiary-care hospital

Summarized from European Society of Gynecology, 2018; Nanna, 2014; Thorne, 2006

TABLE 52-4. Risks for Fetal Heart Lesions Related to

Affected Family Members

Congenital Heart Disease in

Fetus (%)

Cardiac Lesion

Previous

Sibling

Affected

Father

Affected

Mother

Affected

Aortic stenosis 2 3 15–18

Pulmonary stenosis 2 2 6–7

Ventricular septal defect 3 2 10–16

Atrial septal defect 2.5 1.5 5–11

Patent ductus arteriosus 3 2.5 4

Coarctation of the aorta NS NS 14

Fallot tetralogy 2.5 1.5 2–3

Marfan syndrome NS 50 50

NS = not stated.

cardiovascular disease morbidity and mortality: (1) race/ethnicity, with morbidity highest in Arican-American women; (2)

age, with increased morbidity in women older than 40 years;

(3) hypertension o all varieties; (4) obesity, with higher morbidity associated with increasing degrees o obesity (Ackerman,

2019). o these, social and health disparities could be added

because lower income, ood and housing insecurity, and lack o

childcare are directly linked to underutilization o prenatal care

(Gadson, 2017). In turn, lack o prenatal care is a risk actor or

maternal morbidity and mortality (Howland, 2019).

■ Antepartum Care

In most instances, management involves a team approach with

an obstetrician, cardiologist, anesthesiologist, and other specialists as needed. With complex lesions or other high-risk cases,

evaluation by a multidisciplinary team is recommended early in

pregnancy. Both prognosis and management are inuenced by

the type and severity o the specic lesion and by the maternal

unctional classication. In some, pregnancy termination may

be advisable.

With rare exceptions, women in NYHA class I and most in

class II negotiate pregnancy without morbidity. Special attention is directed toward both prevention and early recognition

o heart ailure. O specic risks, inection with sepsis can precipitate decompensation. Also, bacterial endocarditis is a deadly

complication o valvular heart disease (p. 934). Each woman is

instructed to avoid contact with persons who have respiratory

inections, including the common cold, and to immediately

report any evidence or inection. Pneumococcal vaccine, i not

previously administered, and yearly inuenza vaccine are recommended (Chap. 10, p. 188).

Cigarette smoking is prohibited. Illicit drug use may be particularly harmul, an example being the cardiovascular eects

o cocaine or amphetamines. In addition, intravenous drug use

raises the inective endocarditis risk.

Fortunately, gravidas in NYHA class III and IV are uncommon today. In the Canadian study, only 3 percent o the

approximately 600 pregnancies were complicated by NYHA

class III heart disease, and no women had class IV when rst

seen (Siu, 2001b). I a woman chooses pregnancy, she must

understand the risks and is encouraged to be compliant with

planned care. In some women, prolonged hospitalization or

bed rest is oten necessary.

■ Labor and Delivery

In general, vaginal delivery is preerred, and labor induction

is usually sae (Turman, 2017). From the large Registry on

Pregnancy and Cardiac Disease, Ruys and associates (2015)

compared pregnancy outcomes between 869 women who

had a planned vaginal delivery and 393 gravidas who had a

planned cesarean delivery. Planned cesarean delivery conerred

no advantage or maternal or neonatal outcome. Similar results

were reported rom Brigham and Women’s Hospital (Easter,

2020).

Cesarean delivery is usually limited to obstetrical indications, and considerations are given or the specic cardiac

lesion, overall maternal condition, and availability o experienced anesthesia personnel and hospital capabilities. Some o

these women tolerate major surgical procedures poorly and are

best delivered in a unit experienced with management o complicated cardiac disease. Occasionally, pulmonary artery catheterization may be needed or hemodynamic monitoring (Chap.

50, p. 883). In our experiences, however, invasive monitoring

is rarely indicated.

Based on her review, Simpson (2012) recommends cesarean

delivery or women with the ollowing: (1) dilated aortic root

>4 cm or aortic aneurysm; (2) acute severe congestive heart

ailure; (3) recent myocardial inarction; (4) severe symptomatic aortic stenosis; (5) need or emergency valve replacement

immediately ater delivery; and (6) wararin administration

within 2 weeks o delivery due to etal risk or intracerebral

hemorrhage because the etal liver takes up to 2 weeks to

metabolize wararin. Although we agree with most o these,

we have some caveats. For congestive heart ailure, we preer

aggressive medical stabilization o pulmonary edema ollowed

by vaginal delivery i possible.

During labor, the mother with signicant heart disease

should be kept in a semirecumbent position with a lateral tilt.

Vital signs are taken requently between contractions. Elevations in pulse rate much above 100 beats per minute (bpm)

or respiratory rate above 24 breaths per minute, particularly

when associated with dyspnea, may suggest impending ventricular ailure. For evidence o cardiac decompensation, intensive

medical management must be instituted immediately. Delivery

itsel does not necessarily improve the maternal condition and,

in act, may worsen it. Moreover, emergency cesarean delivery

may be particularly hazardous. Clearly, both maternal and etal

status must be considered in the decision to hasten delivery

under these circumstances.

Analgesia and Anesthesia

Relie rom pain and rom apprehension is important. Although

intravenous analgesics provide satisactory pain relie or some

women, continuous epidural analgesia is recommended or

most. Te major problem with conduction analgesia is maternalCardiovascular Disorders 921

CHAPTER 52

hypotension (Chap. 25, p. 473). Tis is especially dangerous in

women with intracardiac shunts in whom ow may be reversed.

Hypotension can also be lie-threatening i there is pulmonary

arterial hypertension or aortic stenosis. In these, ventricular

output is dependent on adequate preload. In women with these

conditions, narcotic regional analgesia; low-dose, slow-inusion

epidural; or general anesthesia may be preerable.

For vaginal delivery in women with only mild cardiovascular

compromise, epidural analgesia given with intravenous sedation oten sufces. Tis minimizes intrapartum cardiac output

uctuations and allows orceps or vacuum-assisted delivery.

Incrementally dosed subarachnoid blockade is approached

especially cautiously in women with signicant heart disease

due to associated hypotension. For cesarean delivery, epidural

analgesia is preerred by most clinicians with caution or its use

with pulmonary arterial hypertension (p. 932).

Intrapartum Heart Failure

From the Nationwide Inpatient Sample, one ourth o cases o

heart ailure during pregnancy were encountered intrapartum

(Mogos, 2018). Women with underlying cardiovascular disorders are at higher risk (Schlichting, 2019). Te physiological

stress and uid shits associated with labor and delivery explain

this risk. Catecholamine release due to pain and second stage

Valsalva increase let ventricular work, which can precipitate

heart ailure (Anthony, 2016).

Obstetrical complications can either advance or precipitate heart ailure. Preeclampsia is common and may provoke

aterload ailure (Vaught, 2018). Findings rom the Registry

on Pregnancy and Cardiac Disease indicate that women with

preexisting heart disease who develop preeclampsia have a

30-percent risk o developing heart ailure during pregnancy

(Ruys, 2014). Obesity is another common coactor (Vonck,

2019). Also, high-output states caused by hemorrhage and

acute anemia elevate cardiac workload and magniy the physiological eects o compromised ventricular unction. Similarly, inection and sepsis increase cardiac output and oxygen

utilization and depress myocardial unction.

Chronic hypertension with superimposed preeclampsia is

the most requent cause o heart ailure in pregnancy in numerous populations. Many o these women have preexisting concentric let ventricular hypertrophy (Ambia, 2017, 2018). In

some, mild antecedent undiagnosed hypertension causes covert

cardiomyopathy, and when superimposed preeclampsia develops, together they may cause otherwise inexplicable peripartum heart ailure. Obesity is requently comorbid with chronic

hypertension, and it also is associated with ventricular hypertrophy (Kenchaiah, 2002).

Cardiovascular decompensation during labor may mani-

est as pulmonary edema with hypoxia or as hypotension, or

both. Te proper therapeutic approach depends on the specic

hemodynamic status and the underlying cardiac lesion. Continuous pulse oximetry and invasive blood pressure monitoring

with an arterial line is helpul in some cases (Easter, 2020) In

general, pulmonary edema due to uid overload is oten best

treated with aggressive diuresis. I precipitated by tachycardia,

heart rate control with β-blocking agents is preerred. However, unless the underlying pathophysiology is understood and

the cause o the decompensation is clear, empirical therapy may

be hazardous. Details o heart ailure management and specic

cardiovascular disorders are discussed below.

■ Puerperium

Women who have shown little or no evidence o cardiac compromise during pregnancy, labor, or delivery may still decompensate postpartum (Mogos, 2018). Fluid mobilized into the

intravascular compartment and reduced peripheral vascular

resistance place higher demands on myocardial perormance.

Tereore, meticulous care is continued into the puerperium

(Sliwa, 2018; Zeeman, 2006). Postpartum hemorrhage, anemia, inection, and thromboembolism are much more serious

complications with heart disease. Indeed, these actors oten

act in concert to precipitate postpartum heart ailure. In addition, sepsis and severe preeclampsia cause or worsen pulmonary

edema because o endothelial activation and capillary-alveolar

leakage. For example, women with pregnancy-associated hypertensive diseases have a greater risk or readmission or heart

ailure within 90 days o delivery (Nizamuddin, 2019).

For puerperal tubal sterilization ater vaginal delivery, the

procedure can be delayed up to several days to ensure that the

mother has normalized hemodynamically and that she is aebrile, not anemic, and ambulatory. For those desiring uture

ertility, contraception is crucial (Abarbanell, 2019; Sobhani,

2019). Detailed contraceptive advice is available in the U.S.

Medical Eligibility Criteria or Contraceptive Use guidelines

(Curtis, 2016). Tese are discussed in Chapter 38 (p. 664).

HEART FAILURE

Primary structural or unctional cardiac disorders can lead to

this clinical syndrome caused by impaired ventricular unction.

Mitral stenosis, pulmonary hypertension, and peripartum cardiomyopathy are some examples. Chronic pressure overload

leads to ventricular dilation and impaired unction over time.

Associated perinatal mortality rates are high (Bright, 2021).

■ Diagnosis

Heart ailure is best thought o as chronic underlying ventricular

myopathy with episodic worsening causing clinical symptoms

(Packer, 2019). Tus, ailure can have a gradual onset or may

present as acute “ash” pulmonary edema. In pregnant women,

onset is most likely at the end o the second or beginning o

the third trimester and peripartum (Ruys, 2014). O symptoms,

dyspnea is universal and others are orthopnea, palpitations, substernal chest pain, nocturnal cough, and a sudden decline in

the ability to complete usual duties. Clinical ndings include

persistent basilar rales, hemoptysis, progressive edema, tachypnea, and tachycardia. According to Malhamé and associates

(2019), serum levels o brain natriuretic peptide (BNP) are variably elevated (Appendix, p. 1231). Cardiomegaly and pulmonary edema are hallmark radiographic ndings. Acutely, there is

usually systolic ailure. Echocardiography may show an ejection

raction <0.45 or a ractional shortening <30 percent, or both,

and an end-diastolic dimension >2.7 cm/m2 (Hibbard, 1999).922 Medical and Surgical Complications

Section 12

Coincidental diastolic ailure also may be ound, depending on

the underlying cause (Redeld, 2016). Last, the cause o ventricular dysunction—such as valvular abnormalities or concentric

hypertrophy—may become apparent.

■ Management

Pulmonary edema rom heart ailure usually responds promptly

with diuretic administration to reduce preload. Recall that

urosemide (Lasix) is a potent venodilator in addition to its

diuretic action. Hypertension is common in pregnancy, and

aterload reduction is accomplished with hydralazine, niedipine, or another vasodilator. Angiotensin-converting enzyme

inhibitors are withheld until ater delivery because o marked

etal eects (Chap. 8, p. 150). β-blocking agents lower mortality rates in the setting o heart ailure, and carvedilol (Coreg) is

commonly used in pregnancy. Last, digoxin provides inotropic

support and is associated with decreased hospitalizations. With

chronic heart ailure, the incidence o associated thromboembolism is high, and thereore prophylactic heparin is oten recommended.

Let ventricular assist devices are now employed more

requently or acute and chronic heart ailure treatment. A

ew reports describe their use during pregnancy (Hamdan,

2017; Makdisi, 2017). Extracorporeal membrane oxygenation

(ECMO) was reported to be liesaving in a woman with ulminating peripartum cardiomyopathy, and it may be used in

women with pulmonary hypertension (Meng, 2017; Pacheco,

2018).

SURGICALLY CORRECTED HEART DISEASE

Most clinically signicant congenital heart lesions are repaired

during childhood. Tose requently not diagnosed until adulthood include atrial septal deects, pulmonic stenosis, bicuspid

aortic valve, and aortic coarctation (Brickner, 2014). In some

cases, the deect is mild and does not require repair. In others,

a signicant anomaly is amenable to corrective surgery, per-

ormed ideally beore pregnancy. Rarely, surgical corrections

are necessary during pregnancy.

■ Valve Replacement Before Pregnancy

Numerous reports describe subsequent pregnancy outcomes

in women who have a prosthetic mitral or aortic valve placed

beore pregnancy. From one review, the overall estimated

maternal mortality rate was 1.2 percent (Lawley, 2015). Using

the Registry o Pregnancy and Cardiac Disease, the maternal

mortality rate was 1.4 percent in women with a mechanical

heart valve and 1.5 percent in women with a tissue heart valve

(van Hagen, 2015). Compared with the general maternal mortality rate measured per 100,000 births, this risk is more than

50-old higher (Chap. 1, p. 4).

Te type o valve, either mechanical or bioprosthetic, is

paramount. From the just-described cohort, mechanical heart

valve thrombosis complicated 4.7 percent. Only 58 percent o

women with a mechanical heart valve had a pregnancy ree o

serious adverse events compared with 79 percent o patients

with a tissue heart valve (Table 52-5) (van Hagen, 2015). A

study o 417 women showed that pregnancy loss occurred in

61 and 15 percent with mechanical and bioprosthetic valves,

respectively (Batra, 2018). Anticoagulation is a requisite with

mechanical valves because o thrombosis risks, and its complications are described in the next section. Tus, pregnancy is

undertaken only ater serious consideration or women with a

mechanical valve.

Bouhout and associates (2014) reported the outcomes o

27 pregnancies in 14 women who underwent an aortic valve

replacement prior to pregnancy. Seven o the 27 pregnancies

occurred in ve women with a mechanical valve. Complications in this group included two embolic myocardial inarctions and one each o miscarriage, postpartum hemorrhage,

placental abruption, and preterm birth. In the bioprosthetic

group, there were nine miscarriages.

Adverse maternal and etal outcomes plague also women

with a mechanical mitral valve. In one report o 28 pregnancies, Vause and colleagues (2017) described severe maternal

morbidity and mortality in 57 percent. A review o pregnancy

outcomes in 800 women reported similar results (Steinberg,

2017).

Porcine tissue mitral valves are saer during pregnancy, primarily because thrombosis is rare, and anticoagulation is not

required (see able 52-5). However, valvular dysunction with

cardiac deterioration poses a serious risk. Another drawback is

that bioprostheses are less durable than mechanical ones, and

valve replacement longevity averages 10 to 15 years. Batra and

coworkers (2018) concluded that pregnancy accelerated the

risk or subsequent replacement.

Anticoagulation

Tis is critical or women with mechanical valves. Unortunately, wararin is the most eective anticoagulant or preventing maternal thromboembolism but causes harmul etal

eects. As seen in Table 52-6, anticoagulation with heparin

is less hazardous or the etus, however, the risk o maternal

thromboembolic complications is increased (Steinberg, 2017).

As a compromise, some use heparin in early pregnancy, and

then transition to wararin in the second trimester.

Wararin is teratogenic and causes miscarriages, stillbirths,

and etal malormations (Chap. 8, p. 156). In one study o

TABLE 52-5. Selected Outcomes in Pregnancies

Complicated by Heart-Valve Replacement

Outcome

Mechanical

Valve (n = 212)

Tissue Valve

(n = 134)

Maternal mortality 3 (1.4) 2 (1.5)

Heart failure 162 (7.5) 1 (8.2)

Thrombotic complication 13 (6.1) 1 (0.7)

Hemorrhagic complication 49 (23) 7 (5.1)

Pregnancy loss <24 weeks 33 (15.6) 2 (1.5)

Stillbirth 6 (2.8) 0 (0)

Preterm birth <37 weeks 29 (18) 24 (19)

Data presented as n (%).Cardiovascular Disorders 923

CHAPTER 52

TABLE 52-6. Maternal and Fetal Composite Outcomes

in 800 Women with a Mechanical Heart

Value Receiving Anticoagulation

Treatment

Composite Adverse Outcome (%)

Maternala Fetalb

VKA 5 39

LMWH 16 14

LMWHc followed by VKA 16 16

UFHc followed by VKA 16 34

aMaternal death, valve failure, thromboembolism.

bMiscarriage, fetal death, congenital malformation.

cDuring first trimester.

LMWH = low-molecular-weight heparin; UFH = unfractionated heparin; vitamin K antagonist.

71 women given wararin throughout pregnancy, the rates o

miscarriage were 32 percent; stillbirth, 7 percent; and embryopathy, 6 percent (Cotruo, 2002). Te risk was highest when

the mean daily dose o wararin exceeded 5 mg. Similarly,

the American College o Cardiology and the American Heart

Association estimate that the risk o embryopathy is dose

dependent, and the risk is <3 percent i the wararin dose is

≤5 mg/d (Nishimura, 2014). Women treated with <5 mg/d

o wararin had etal risks similar to the low-molecular-weight

heparin (LMWH) regimen (Steinberg, 2017). I the dosage is

>5 mg/d, the risk o embryopathy exceeds 8 percent.

Anticoagulation or mechanical valves using low-dose unractionated heparin (UFH) is denitely inadequate and carries a

high associated maternal mortality rate (Chan, 2000; IturbeAlessio, 1986). Even ull anticoagulation with either UFH

or one o the LMWHs is associated with valvular thrombosis (Leyh, 2002, 2003; Rowan, 2001). However, compliance

with dosing and therapeutic monitoring may have contributed

(McLintock, 2014). Tereore, i ull anticoagulation with doseadjusted UFH or LMWH is used, meticulous monitoring is recommended. Te activated partial thromboplastin time (aP)

should be at least 2 times control or anti-Xa levels should be 0.8

to 1.2 U/mL at 4 to 6 hours postdose (Nishimura, 2014).

Recommendations for Anticoagulation

Several dierent treatment options exist, although all are principally based on consensus opinion, and none is completely ideal.

Wararin and LMWH are associated with ewer valve thromboses and thereore avored over subcutaneous UFH (D’Souza,

2017). In addition, therapeutic subcutaneous UFH dosing is

difcult to achieve due to lower peak plasma concentrations in

pregnant women, especially with advancing gestation (Barbour,

1995; Brancazio, 1995). One guideline rom the American College o Cardiology and the American Heart Association oers

dierent treatment options based on trimester and baseline war-

arin dose (Nishimura, 2014). Figure 52-3 displays a treatment

algorithm based on these guidelines. All recommendations also

include aspirin 75 to 100 mg orally daily.

Vaginal or cesarean delivery is ideally scheduled to allow controlled discontinuation o anticoagulation and partial reversal

o its eects. Tis also permits administration o regional anesthesia, which requires a degree o coagulation to avoid epidural

hematoma ormation (Chap. 25, p. 478). I delivery intervenes

while the anticoagulant is still eective, and extensive bleeding is encountered, protamine sulate is given intravenously

to reverse heparin eects. Patients should be counseled that in

these situations regional anesthesia may not saely be possible.

Following vaginal delivery, anticoagulant therapy with war-

arin or heparin may be restarted 6 hours later, usually with no

problems. Following cesarean delivery, ull anticoagulation is

withheld, but the optimal duration is unclear. Te American

College o Obstetricians and Gynecologists (2018a) recommends resuming UFH or LMWH 6 to 12 hours ater cesarean delivery. At Parkland Hospital, however, we wait at least

24 hours ollowing a major surgical procedure given inherent

bleeding risks. Following rst-trimester dilation and curettage

heparin is begun immediately.

Wararin, LMWH, and UFH are compatible with breast-

eeding. Tey do not accumulate in breast milk and thus do

not induce anticoagulant eects in the newborn (Briggs, 2022).

■ Cardiac Surgery During Pregnancy

Although usually postponed until ater delivery, valve replacement or other cardiac surgery during pregnancy may be liesaving. Several reviews conrm that such surgery is associated

with major maternal and etal morbidity (Liu, 2021). Elassy

and associates (2014) described 23 women who underwent

urgent open cardiac surgery or severe valve malunction.

wo women and 10 etuses—all at a gestational age below

28 weeks—died beore hospital discharge. Only six etuses

were delivered at term. In a review o 154 women undergoing

bypass surgery during pregnancy, the maternal mortality rate

was 11 percent, and the etal loss rate was 33 percent (Jha,

2018). o optimize outcomes, Chandrasekhar and coworkers (2009) recommend that surgery be elective when possible,

pump ow rate should remain >2.5 L/min/m2, perusion

pressure should exceed 70 mm Hg, and hematocrit should be

kept >28 percent.

■ Pregnancy after Heart Transplantation

Many successul pregnancies have ollowed cardiac transplantation (D’Souza, 2018; Macera, 2018). Current recommendations rom the International Society o Heart and Lung

ransplantation do not discourage pregnancy in stable heart

transplant recipients who are more than 1 year posttransplant

(Costanzo, 2010). Obviously, a highly specialized level o care

and multidisciplinary team is necessary.

Te transplanted heart appears to respond normally to

pregnancy-induced alterations (Cowan, 2012). Despite this,

complications are common during pregnancy. O 103 pregnancies in 57 heart recipients rom the National ransplantation

Pregnancy Registry, almost hal developed hypertension, and

11 percent suered at least one rejection episode during pregnancy (Coscia, 2010). Tey were usually delivered by cesarean

at a mean o 37 weeks’ gestation. Lie expectancy ollowing

heart transplantation is known to be limited. At ollow-up,924 Medical and Surgical Complications

Section 12

FIGURE 52-3 Algorithm for anticoagulation in gravidas with a mechanical heart valve. INR = international normalized ratio; IV = intravenous;

LMWH = low-molecular-weight heparin; aPTT = activated partial thromboplastin time; UFH = unfractionated heparin. (From Elkayam, 2020;

Nishimura, 2014; Roeder, 2011.)

at least 16 women had died more than 2 years postpartum. In

another small study, pregnancy itsel did not worsen long-term

survival rates (Dagher, 2018).

VALVULAR HEART DISEASE

Rheumatic ever is uncommon in the United States because o

less crowded living conditions, penicillin availability, and evolution o nonrheumatogenic streptococcal strains. Still, it remains

the chie cause o serious mitral valvular disease in women o

childbearing age in the nonindustrialized world (Liaw, 2021;

van Hagen, 2018).

■ Mitral Stenosis

Rheumatic endocarditis causes most mitral stenosis lesions. Te

normal mitral valve surace area is 4.0 cm2, and when stenosis

narrows this to <2.5 cm2, symptoms usually develop. Te contracted valve impedes blood ow rom the let atrium to the

ventricle.

With more severe stenosis, the let atrium dilates, let

atrial pressure is chronically elevated, and signicant pulmonary hypertension develops (Table 52-7) (Galiè, 2016).

Tese women have a relatively xed cardiac output, and thus

the increased preload o normal pregnancy and other actors

that raise cardiac output may cause ventricular ailure andCardiovascular Disorders 925

CHAPTER 52

pulmonary edema. Cardiac ailure develops or the rst time

during pregnancy in one ourth o women with mitral stenosis

(Caulin-Glaser, 1999). Te resulting pulmonary venous hypertension and pulmonary edema create symptoms o dyspnea,

atigue, palpitations, cough, and hemoptysis. Te classic murmur may not be heard in some women, and this clinical picture

at term may be conused with idiopathic peripartum cardiomyopathy (Cunningham, 1986, 2019).

Also with signicant stenosis, tachycardia shortens ventricular

diastolic lling time and elevates the mitral gradient. Tis too

may lead to pulmonary edema, and thereore, sinus tachycardia

is oten treated prophylactically with β-blocking agents. Atrial

tachyarrhythmias, including brillation, are common in mitral

stenosis and are treated aggressively. Atrial brillation predisposes

to mural thrombus ormation and cerebrovascular embolization

that can cause stroke (Chap. 63, p. 1132). Atrial thrombosis can

also develop despite a sinus rhythm (Hameed, 2005).

Pregnancy Outcomes

In general, complications are directly associated with the degree

o valvular stenosis. Women with a mitral-valve area <2 cm2

are at greatest risk (Siu, 2001b). In one study o 273 gravidas with mitral stenosis, 43 percent developed heart ailure,

and almost a ourth o these women required admission (van

Hagen, 2018). For women with severe stenosis, hal developed

heart ailure, and one woman died. Fetal-growth restriction was

more common in women with a mitral valve area <1.0 cm2.

Prognosis also is related to maternal unctional capacity. Among 486 pregnancies complicated by rheumatic heart

disease—predominantly mitral stenosis—8 o 10 maternal deaths

were in women in NYHA classes III or IV (Sawhney, 2003).

Management

Limited physical activity is generally recommended in women

with mitral stenosis. I symptoms o pulmonary congestion

develop, activity is urther reduced, dietary sodium is restricted,

and diuretics are given. Also, β-blocker drug therapy slows the

ventricular response to activity. I new-onset atrial brillation

develops, intravenous verapamil, 5 to 10 mg, is given, or electrocardioversion is perormed. For chronic brillation, digoxin,

a β-blocker, or a calcium-channel blocker can slow ventricular

response. Terapeutic anticoagulation is indicated with persistent brillation, let atrial thrombus, and/or a history o embolism (Nanna, 2014).

Surgical intervention is considered or women with symptomatic severe mitral stenosis. Other candidates are those with

mitral-valve area 1.5 to 2.0 cm2 complicated by recurrent systemic

embolization or severe pulmonary hypertension. Balloon valvuloplasty is preerred i the valve is pliable (Bui, 2014). In one review

o 71 pregnant women with severe mitral stenosis and heart ailure who underwent percutaneous valvuloplasty, 98 percent were

either NYHA class I or II by the time o delivery (Esteves, 2006).

At a mean o 44 months, the total event-ree maternal survival

rate was 54 percent. However, eight women required another surgical intervention. All o the 66 newborns who were delivered at

term had normal growth and development.

Labor and delivery are particularly stressul or women with

symptomatic mitral stenosis. Pain, exertion, and anxiety cause

tachycardia with possible rate-related heart ailure. Epidural

analgesia or labor is ideal. Fluid overload should be avoided,

and these women are best managed on the “dry” side. As

shown in Figure 52-4 uterine contractions raise cardiac output

by increasing circulating blood volume. Abrupt expansion in

preload may elevate pulmonary capillary wedge pressure and

cause pulmonary edema. Wedge pressures rise immediately

postpartum. One hypothesis or this suggests that the loss o

the low-resistance placental circulation couples with venous

“autotransusion” rom a now-empty, contracted uterus and

rom the lower extremities and pelvis (Clark, 1985). Tus, pulmonary edema may maniest immediately postpartum.

TABLE 52-7. Major Cardiac Valve Disorders

Type Cause Pathophysiology Pregnancy

Mitral stenosis Rheumatic valvulitis LA dilation and passive

pulmonary hypertension

Atrial fibrillation

Heart failure from fluid overload,

tachycardia

Mitral insufficiency Rheumatic valvulitis

Mitral valve prolapse

LV dilation

LV dilation and eccentric

hypertrophy

Ventricular function improves with

afterload decrease

Aortic stenosis Congenital bicuspid valve LV concentric hypertrophy,

decreased cardiac output

Moderate stenosis is tolerated; severe

is life-threatening with decreased

preload, e.g., obstetrical hemorrhage

or regional analgesia

Aortic insufficiency Rheumatic valvulitis

Connective tissue disease

Congenital

LV hypertrophy and dilation Ventricular function improves with

afterload decrease

Pulmonary stenosis Rheumatic valvulitis

Congenital

Severe stenosis associated

with RA and RV

enlargement

Mild stenosis usually well tolerated;

severe stenosis associated with right

heart failure and atrial arrhythmias

LA = left atrium; LV = left ventricle; RA = right atrium; RV = right ventricle.926 Medical and Surgical Complications

Section 12

Most preer vaginal delivery in women with mitral stenosis.

Elective induction is reasonable so that labor and delivery are

attended by a scheduled, experienced team. With severe stenosis and chronic heart ailure, insertion o a pulmonary artery

catheter may help guide management.

■ Mitral Insufficiency

A trivial degree o mitral insufciency is ound in most normal

patients. But i mitral valve leaets align improperly during

systole, abnormal degrees o mitral regurgitation can develop.

Tis is eventually ollowed by let ventricular dilation and

eccentric hypertrophy (see able 52-7). Acute mitral insu-

ciency is caused by chordae tendineae rupture, papillary muscle

inarction, or leaet peroration rom inective endocarditis.

Chronic mitral regurgitation, in contrast, may derive rom

rheumatic ever, connective tissue diseases, mitral valve prolapse, or let ventricular dilation o any etiology—or example, dilated cardiomyopathy. Less common causes include a

calcied mitral annulus, possibly some appetite suppressants,

and in older women, ischemic heart disease. Mitral valve vegetations—Libman-Sacks endocarditis—are relatively common

in women with antiphospholipid antibodies (Shro, 2012).

Tese sometimes coexist with systemic lupus erythematosus

(Chap. 62, p. 1114).

In nonpregnant patients, symptoms rom mitral valve

insufciency are rare, and valve replacement is seldom indicated unless inective endocarditis develops. During pregnancy, mitral regurgitation is similarly well tolerated, probably

because the lowered systemic vascular resistance yields less

regurgitation. In the report by van Hagen and associates

(2018), o 117 women with moderate or severe regurgitation,

23 percent developed heart ailure during pregnancy. Occasionally tachyarrhythmias or severely depressed systolic unction require treatment.

■ Mitral Valve Prolapse

Tis diagnosis implies the presence o a pathological connective

tissue disorder—oten termed myxomatous degeneration—which

may involve the valve leaets, the annulus, or the chordae tendineae. Mitral insufciency may develop. Most women with

mitral valve prolapse are asymptomatic and are diagnosed during routine examination or echocardiography. Te ew women

with symptoms have anxiety, palpitations, atypical chest pain,

dyspnea with exertion, and syncope (Guy, 2012).

Pregnant women with mitral valve prolapse rarely have

cardiac complications. Hypervolemia may even improve

alignment o the mitral valve, and women without pathological myxomatous degeneration generally have excellent pregnancy outcomes (Leśniak-Sobelga, 2004). For women who

are symptomatic, β-blocking drugs diminish sympathetic

tone, relieve chest pain and palpitations, and reduce the risk

o lie-threatening arrhythmias.

■ Aortic Stenosis

Since the decline in incidence o rheumatic disease, congenital

bicuspid valve is now the most requent cause o aortic stenosis

in young women in the United States (Carabello, 2017). A normal aortic valve has an area o 3 to 4 cm2, with a pressure gradient <5 mm Hg. I the valve area is <1 cm2, ow is severely

obstructed, and progressive pressure overload on the let ventricle develops. Concentric let ventricular hypertrophy ollows,

and i it is severe, end-diastolic pressures become elevated,

ejection raction decreases, and cardiac output is reduced (see

able 52-7). Severity is estimated by peak velocity o ow across

the aortic valve. Mild stenosis has a peak velocity o 2–2.9 m/s,

moderate 3-3.9 m/s, and severe ≥4 m/s. Corresponding mean

pressure gradients are <20, 20–39, and ≥40 mm Hg, respectively (Carabello, 2017). Characteristic maniestations develop

late and include chest pain, syncope, heart ailure, and sudden

death rom arrhythmias. In asymptomatic patients, the mortality rate is 1 percent per year, but with symptoms it increases

to 25 percent per year. Tus, valve replacement is indicated or

symptomatic patients.

Pregnancy

In one single-center study, aortic stenosis accounted or 15 percent o cases o congenital heart disease in 178 pregnant women

(Kim, 2019). Tat said, clinically signicant aortic stenosis is

inrequent during pregnancy. Mild to moderate degrees o stenosis are well tolerated. Severe disease is lie-threatening and

carries a 6-percent mortality risk (Lin, 2017). Te principal

underlying hemodynamic problem is the xed cardiac output

associated with severe stenosis. During pregnancy, several common events acutely lower preload urther and thus aggravate the

xed cardiac output. Tese include vena caval occlusion rom

the gravid uterus, regional analgesia, sepsis, and hemorrhage.

From the earlier-cited Canadian study, complication rates were

higher i the aortic valve area measured <1.5 cm2 (Siu, 2001b).

Management

For asymptomatic women with aortic stenosis, no treatment except

close observation is required. Management o a symptomatic

Pulmonary capillary wedge pressure

(mm Hg)

25

A B

Time-arbitrary units

C D E

5 0

10

15

20

A C

E

B

D

FIGURE 52-4 Mean pulmonary capillary wedge pressure measurements (red graph line) in eight women with mitral valve stenosis. Shaded yellow and blue boxes are mean (± 1 SD) pressures in

nonlaboring normal women at term. A. First-stage labor. B. Second-stage labor 15 to 30 minutes before delivery. C. Postpartum 5

to 15 minutes. D. Postpartum 4 to 6 hours. E. Postpartum 18 to

24 hours. (Data from Clark, 1985, 1989.)Cardiovascular Disorders 927

CHAPTER 52

woman is undertaken in conjunction with a cardiologist and

includes strict limitation o activity and cautious use o diuretics. I symptoms persist, surgical intervention or preterm

delivery may be considered. Catheter-based valvuloplasty is

associated with risks to both the mother and etus and shows

poor long-term efcacy (Pessel, 2014). Namely, the aortic valve

can again narrow or new aortic regurgitation may develop. Te

alternative surgical approach—valve replacement—is associated with signicant risk o etal demise due to the hypotension associated with cardiac bypass. ranscatheter aortic valve

replacement (AVR) has been perormed in low-risk nonpregnant women, but there is little experience with this procedure

during pregnancy (Hodson, 2016; Mack, 2019). Accordingly,

the American College o Cardiology, the American Heart Association, and the European Society o Cardiology recommend

delaying conception until ater surgical correction or severe

aortic stenosis (Nishimura, 2014; Regitz-Zagrosek, 2018). For

those with uncorrected severe symptomatic aortic stenosis,

cesarean delivery is preerred. For asymptomatic women with

severe stenosis, care is individualized. In nonsevere stenosis,

vaginal delivery is preerred (Regitz-Zagrosek, 2018).

For women with critical aortic stenosis, intensive monitoring during labor is essential. Pulmonary artery catheterization may be helpul because o the narrow margin separating

uid overload rom hypovolemia. Women with aortic stenosis are dependent on adequate end-diastolic ventricular lling

pressures to maintain cardiac output and systemic perusion.

Abrupt drops in end-diastolic volume may result in hypotension, syncope, myocardial inarction, and sudden death. Tus,

avoiding diminished ventricular preload and maintaining cardiac output are key. During labor and delivery, aected women

are best managed on the “wet” side. Tis provides a margin o

saety in intravascular volume in anticipation o possible hemorrhage. In women with a competent mitral valve, pulmonary

edema is rare.

During labor, narcotic or low-dose, slow-inusion epidural

analgesia seems ideal and avoids potentially hazardous hypotension. Easterling and coworkers (1988) studied the eects

o epidural analgesia in ve women with severe stenosis and

demonstrated immediate and proound eects rom decreased

lling pressures. Xia and colleagues (2006) emphasize slow

administration o dilute local anesthetic agents into the epidural space. In hemodynamically stable women, orceps or vacuum delivery is used only or standard obstetrical indications.

In those experiencing dizziness, shortness o breath, or tachycardia with pushing, an operative vaginal delivery is preerred.

■ Aortic Insufficiency

Aortic valve regurgitation or insufciency allows diastolic ow

o blood rom the aorta back into the let ventricle. Frequent

causes o insufciency are rheumatic ever, connective tissue

abnormalities, and congenital lesions (Carabello, 2017). With

Maran syndrome, the aortic root may dilate and create regurgitation (p. 936). Acute insufciency may also develop with

bacterial endocarditis or aortic dissection. Last, aortic and

mitral valve insufciency have both been linked to the appetite suppressants enuramine and dexenuramine and to the

ergot-derived dopamine agonists cabergoline and pergolide

(Schade, 2007; Zanettini, 2007). With chronic insufciency,

let ventricular hypertrophy and dilation develop. Slow-onset

atigue, dyspnea, and pulmonary edema ollows ventricular

dilation with subsequent rapid deterioration (see able 52-7).

Aortic insufciency is generally well tolerated during

pregnancy. Like mitral valve insufciency, reduced vascular

resistance is thought to improve hemodynamic unction. I

symptoms o heart ailure develop, diuretics are given, and bed

rest is encouraged.

■ Pulmonic Stenosis

Tis lesion is usually congenital and may be associated with Fallot tetralogy or Noonan syndrome (Chikwe, 2017). Te greater

hemodynamic burden o pregnancy can precipitate right-sided

heart ailure or atrial arrhythmias in women with severe stenosis. Surgical correction ideally is done beore pregnancy, but i

symptoms progress, a balloon valvuloplasty may be necessary

antepartum (Galal, 2015; Siu, 2001a).

In studying pregnancy outcomes, Drenthen and associates

(2006) ound inrequent cardiac complications in 81 pregnancies in 51 Dutch women with pulmonic stenosis. Te NYHA

classication worsened in two women, and nine experienced

palpitations or arrhythmias. No changes in pulmonary valvular

unction or other adverse cardiac events were reported. However, noncardiac complication rates were signicant—17 percent had preterm delivery, 15 percent had hypertension, and

4 percent developed thromboembolism.

CONGENITAL HEART DISEASE

Te incidence o congenital heart disease in the United States

approximates 1.9 percent o live births, and hal o these are

moderate to severe orms (Lin, 2017). With modern surgeries, approximately 90 percent o those born with congenital

heart disease survive to childbearing age, and it is now the most

common type o heart disease encountered during pregnancy

(Hopkins, 2018). Specically, analysis rom the United States

Nationwide Inpatient Sample database showed a linear rise in

the prevalence o congenital heart disease between 2000 and

2010—rom 6.4 to 9.0 per 10,000 women admitted or delivery (Tompson, 2015).

Te odds o obstetrical and perinatal complications are

increased two- to threeold in women with congenital heart disease compared with unaected women (Ramage, 2019). Also,

the maternal mortality rate was higher or women with congenital heart disease at 178 per 100,000 deliveries compared

with 7 per 100,000 deliveries in unaected gravidas (Tompson, 2015).

■ Atrial Septal Defects

A patent oramen ovale (PFO) is a persisting incompetence o

the ossa ovale, and this ap has the potential to open under

increased hydrostatic pressure. O all adults, approximately

one ourth have this deect (Silvestry, 2015). Te small risk o

PFO-related stroke, discussed subsequently, is likely higher in928 Medical and Surgical Complications

Section 12

pregnant than in nonpregnant women and mainly attributed to

normal pregnancy hypercoagulability (Chen, 2016). Preventive

PFO repair is not recommended (Kernan, 2014).

An atrial septal deect (ASD) is a true hole in the septum.

Te secundum-type deect accounts or 70 percent, and associated mitral valve myxomatous abnormalities with prolapse

are common. Most ASDs are typically asymptomatic until the

third or ourth decade o lie (Lin, 2017). I an ASD is discovered in adulthood, most recommend repair.

Pregnancy with an unrepaired ASD is well tolerated unless

pulmonary hypertension has developed, but this is uncommon

(Bredy, 2018). Medical treatment during pregnancy is indicated or congestive heart ailure or an arrhythmia. Te risk o

endocarditis with an ASD is negligible.

With the potential to shunt blood rom right to let, a paradoxical embolism is possible. A venous thrombus enters the systemic arterial circulation through the ASD, causing an embolic

stroke (Bredy, 2018). For this reason, lters should be placed

on intravenous access sites. In a gravida with an ASD but without current venous thromboembolism (VE), the decision to

add anticoagulant prophylaxis to counter this potential embolism risk is problematic. However, or a pregnant woman with

an ASD who is immobile or has another risk actor or thromboembolism, compression stockings and prophylactic heparin

are reasonable.

■ Ventricular Septal Defects

Tese lesions close spontaneously during childhood in 90 percent o cases. O the our main ventricular septal deect (VSD)

types, most deects are paramembranous. Tis location is well

below the outlet valves yet above the ventricular musculature.

Te degree o associated let-to-right shunt and physiological

derangements are related to lesion size. In general, i the deect

measures <1.25 cm2, pulmonary hypertension and heart ailure

do not develop. I the eective deect size exceeds that o the

aortic valve orice, symptoms rapidly develop. For these reasons, most children undergo surgical repair beore pulmonary

hypertension develops. Adults with unrepaired large deects

develop let ventricular ailure and pulmonary hypertension and

have a high incidence o bacterial endocarditis (Brickner, 2014).

Pregnancy is well tolerated with small- to moderate-sized

VSD shunts. However, i pulmonary arterial pressures reach

systemic levels, ow is reversed or bidirectional—Eisenmenger

syndrome (p. 929). I this cyanotic condition develops, the

maternal and etal mortality rates are signicantly higher, and

thus pregnancy is generally not advisable (Lin, 2017). Bacterial endocarditis is more common with unrepaired deects, and

antimicrobial prophylaxis is oten required (p. 934). As shown

in able 52-4, 16 percent o ospring born to these women

also have a VSD.

■ Atrioventricular Septal Defects

An atrioventricular (AV) septal deect is characterized by a

common, ovoid AV junction. Tese account or approximately

3 percent o all congenital cardiac malormations and are distinct rom isolated ASDs or VSDs. Tis deect is associated with

aneuploidy, Eisenmenger syndrome, and other malormations

(Foeller, 2018). Compared with simple septal deects, complications are more requent during pregnancy. In a review o

48 pregnancies in 29 aected women, complications included

persistent deterioration o NYHA class in 23 percent, signi-

cant arrhythmias in 19 percent, and heart ailure in 2 percent

(Drenthen, 2005). Congenital heart disease was identied in

15 percent o the ospring.

■ Persistent (Patent) Ductus Arteriosus

Te ductus connects the proximal let pulmonary artery to

the descending aorta just distal to the let subclavian artery.

Functional closure o the ductus rom vasoconstriction occurs

shortly ater term birth. Te physiological consequences with

its persistence are related to its size. Most signicant lesions

are repaired in childhood. However, in women with an unrepaired ductus, pulmonary hypertension, heart ailure, or cyanosis will develop i systemic blood pressure alls and blood

ow reverses rom the pulmonary artery into the aorta (Foeller,

2018). A sudden blood pressure decline at delivery—such as

with regional analgesia or hemorrhage—may lead to atal collapse. Tereore, hypotension is avoided but treated vigorously

i it develops. Prophylaxis or bacterial endocarditis is indicated at delivery or unrepaired deects (p. 934). As shown in

able 52-4, the incidence o inheritance approximates 4 percent.

■ Cyanotic Heart Disease

Cyanosis develops when congenital heart lesions produce rightto-let shunting o blood past the pulmonary capillary bed. Te

classic and most commonly encountered lesion in adults and

during pregnancy is the Fallot tetralogy (Foeller, 2018). Tis

is characterized by a large VSD, pulmonary stenosis, right

ventricular hypertrophy, and an overriding aorta that receives

blood rom both the right and let ventricles. Te magnitude

o the shunt varies inversely with systemic vascular resistance.

Hence, during pregnancy, when peripheral resistance decreases,

shunt ow increases and cyanosis worsens.

Generally, women with cyanotic heart disease do poorly

during pregnancy. Tose with concomitant Eisenmenger syndrome are at greatest risk (p. 929). With uncorrected Fallot

tetralogy, maternal mortality rates approach 10 percent. For

etal outcome, there is a relationship between chronic hypoxemia, polycythemia, and complications such as miscarriage and

perinatal morbidity. When hypoxemia is intense enough to

stimulate a rise in hemoglobin concentration >20 g/dL, pregnancy wastage is virtually 100 percent (Lin, 2017).

Although not all cyanotic lesions are repairable, with satis-

actory surgical correction beore pregnancy, maternal and etal

outcomes are much improved. In a review o 197 pregnancies in

99 women with surgically corrected Fallot tetralogy, pregnancy

was usually well tolerated, and no mothers died (Cauldwell,

2017). Still, almost 9 percent o pregnancies were complicated

by adverse cardiac events including new-onset or worsening

arrhythmias and heart ailure (Balci, 2011; Kamiya, 2012).

Some women with Ebstein anomaly, characterized by a

malpositioned and malormed tricuspid valve, may reachCardiovascular Disorders 929

CHAPTER 52

reproductive age. Te right ventricle is small and the right

atrium is severely dilated. Right-sided heart ailure is common.

Tese women are very preload dependent, and pregnancyinduced hypervolemia can worsen the tricuspid regurgitation

(Kanoh, 2018). Arrhythmias also are common, especially

Wol-Parkinson-White syndrome (p. 936). Vaginal delivery

seems preerable in most cases. In the absence o cyanosis,

heart ailure, or signicant arrhythmias, aected women usually tolerate pregnancy well (Sa, 2016).

■ Pregnancy after Surgical Repair

Transposition of the Great Vessels

Pregnancy ollowing arterial switch operation or transposition is associated with good outcomes. A major concern is

atal arrhythmias that usually are precipitated by exercise (Lin,

2017). Earlier studies cited a relatively high rate o heart ailure

and arrhythmias, but more recent studies have avorable pregnancy outcomes (rigas, 2014). In one study o 20 pregnancies, there were three cases o heart ailure (Horiuchi, 2019).

Stoll and coworkers (2018) reported no adverse cardiac events

in 25 pregnancies.

O other deects, repaired truncus arteriosus and doubleoutlet right ventricle with subsequent successul, although

eventul, pregnancies have been described (Drenthen, 2008;

Hoendermis, 2008). Ironically, preconceptional counseling did little to dissuade these women rom childbearing

(Cauldwell, 2016).

Single Functional Ventricle

With hypoplastic let heart syndrome, most aected women are

now expected to survive into adulthood (Davis, 2018). Frequently, these women become pregnant, and those who have

undergone a Fontan repair carry a particularly higher risk or

complications. In brie, this procedure involves diverting blood

via a surgical anastomosis rom the vena cava to the pulmonary

artery without passing through the right ventricle. Blood ows

passively to the pulmonary vasculature. Preload drives circulation in the Fontan circuit, and thus patients are sensitive to

volume changes (Moroney, 2018).

From their review o 255 pregnancies in 133 women,

Garcia-Ropero and colleagues (2018) reported 115 miscarriages

(45 percent) and 19 elective terminations (7 percent). Cardiac

complications included arrhythmias in 8 percent and heart ailure in 4 percent o pregnancies. Among 133 live births, there

were 68 preterm births (59 percent) and 7 perinatal deaths

(6 percent). Postpartum venous thromboembolism also is common (Moroney, 2020).

Similar complications attend a maternal systemic right ventricle, that is, one in which the right ventricle rather than the

let pumps blood to the systemic circulation (Khan, 2015).

■ Eisenmenger Syndrome

Tis describes secondary pulmonary hypertension that arises

rom any cardiac lesion. Te most common underlying deects

are ASD, VSD, and persistent ductus arteriosus (Fig. 52-5).

Initial left-to-right shunt

A B

Pulmonary

arteriole

Left

atrium

Left

atrium

Right

atrium

Right

atrium

Right

ventricle

Right ventricle

hypertrophy

Narrowed pulmonary

arterioles result and

lead to pulmonary

hypertension

Left

ventricle

Left

ventricle

Pulmonary

artery

Pulmonary

artery

Ultimate right-to-left shunt

FIGURE 52-5 Eisenmenger syndrome due to a ventricular septal defect (VSD). A. Substantial left-to-right shunting through the VSD leads

to morphological changes in the smaller pulmonary arteries and arterioles. Specifically, medial hypertrophy, intimal cellular proliferations,

and fibrosis lead to narrowing or closure of the vessel lumen. These vascular changes create pulmonary hypertension and a resultant reversal of the intracardiac shunt (B). With sustained pulmonary hypertension, extensive atherosclerosis and calcification often develop in the

large pulmonary arteries. Although a VSD is shown here, Eisenmenger syndrome may also develop in association with a large atrial septal

defect or persistent ductus arteriosus.930 Medical and Surgical Complications

Section 12

Te syndrome develops when pulmonary vascular resistance

exceeds systemic resistance and leads to concomitant right-tolet shunting. Patients are asymptomatic or years, but eventually pulmonary hypertension becomes severe enough to cause

this shunting.

Pregnant women with Eisenmenger syndrome tolerate hypotension poorly, and death usually is caused by right ventricular

ailure with cardiogenic shock. In a review o 73 pregnancies,

Weiss and associates (1998) cited a 36-percent maternal death

rate. Tree o 26 deaths were antepartum, and the remainder

o women died intrapartum or within a month o delivery. In

another study o 13 gravidas, one mother died 17 days ater

delivery, and there were ve perinatal deaths (Wang, 2011).

Last, in a series o 11 pregnancies in China, our mothers died

(Duan, 2016). Given such poor outcomes or both mother and

etus, Eisenmenger syndrome is considered to be an absolute contraindication to pregnancy (American College o Obstetricians and

Gynecologists, 2019; Foeller, 2018; Meng, 2017).

PULMONARY HYPERTENSION

Normal resting mean pulmonary artery pressure is 12 to

16 mm Hg. Most dene pulmonary hypertension in nonpregnant

individuals as a resting mean pulmonary pressure >25 mm Hg

(Franco, 2019). Pulmonary vascular resistance in late normal

pregnancy approximates 80 dyne/sec/cm−5, which is 34-percent

less than the nonpregnant value o 120 dyne/sec/cm−5

(Clark, 1989).

Physiologically, pregnancy is associated increased cardiac

output, and in healthy gravidas, pulmonary vascular resistance

decreases to help accommodate this (Clark, 1989). With pulmonary hypertension, the sti pulmonary vasculature does not

allow the normal all in pulmonary vascular resistance. Tus,

the normal increased cardiac output actually leads to urther

pulmonary artery pressure elevation and then eventually to

right heart ailure. With ailure, the interventricular septum

bulges letward to impair let ventricular diastolic lling, which

compromises cardiac output (Gei, 2014; Pieper, 2011).

Te current clinical classication system, shown in

Table 52-8, contains ve groups o disorders that cause pulmonary hypertension (Galiè, 2016). Important prognostic and

therapeutic distinctions separate group 1 pulmonary arterial

hypertension and the other groups. Group 1, which is more

common in nonpregnant women, indicates that a specic

disease aects pulmonary arterioles. It includes idiopathic or

primary pulmonary arterial hypertension as well as those cases

secondary to a known cause such as connective tissue disease.

For example, approximately a third o women with scleroderma

and 10 percent with systemic lupus erythematosus have pulmonary arterial hypertension (Franco, 2019). Other causes

in young women are human immunodeciency virus (HIV)

inection, sickle-cell disease, and thyrotoxicosis.

In pregnant women, group 2 disorders are the most common. Tese are secondary to pulmonary venous hypertension

caused by let-sided atrial, ventricular, or valvular disorders. A

typical example is mitral stenosis discussed earlier (p. 924). In

contrast, groups 3 through 5 are seen inrequently in young

otherwise healthy women.

■ Diagnosis and Prognosis

Symptoms may be vague, and dyspnea with exertion is the

most requent. With group 2 disorders, orthopnea and nocturnal dyspnea are also usually present. Angina and syncope

occur when right ventricular output is xed, and they suggest

advanced disease. Chest radiography oten shows enlarged pulmonary hilar arteries and attenuated peripheral markings. It

may also disclose parenchymal causes o hypertension. Noninvasive echocardiography can provide an estimate o pulmonary

artery pressures, although cardiac catheterization remains the

standard or measurement. In studies o pregnant women who

underwent both echocardiography and cardiac catheterization,

pulmonary artery pressures were signicantly overestimated by

echocardiography in approximately a third o cases (Herrera,

2020; Wylie, 2007).

Regardless o the etiology, the nal common pathway o

pulmonary hypertension is right heart ailure and death. Te

average survival length ater diagnosis is <4 years (Krexi, 2015).

Tat said, longevity depends on the severity and cause o pulmonary hypertension at discovery. As discussed later, some disorders respond to medical interventions, which may improve

quality o lie. Preconceptional and contraceptive counseling

are imperative (American College o Obstetricians and Gynecologists, 2019).

■ Pregnancy

Te maternal mortality rate is appreciable in aected women,

and this is especially so with idiopathic pulmonary arterial

hypertension (Martin, 2019). In the past, the ability to accurately identiy causes and assess disease severity were oten poor.

Tus, although most severe cases o idiopathic pulmonary

arterial hypertension had the worst prognosis, it was erroneously assumed that all types o pulmonary hypertension were

equally dangerous. With widespread use o echocardiography,

less-severe lesions with a better prognosis are now discernible.

Te maternal mortality rate or pulmonary hypertension has

improved. In one study, it was 25 percent during the decade

ending in 2007 compared with 38 percent or the decade ending in 1996 (Bédard, 2009). Importantly, almost 80 percent

o the deaths were during the rst month postpartum. Meng

and associates (2017) reported mortality rates o 23 percent

with group 1 and 5 percent with the other groups. Mortality

risk correlates positively with advancing pulmonary hypertension severity, which is characterized by Eisenmenger syndrome,

severe hypertension, and higher NYHA class (Keepanasseril,

2019; Sun, 2018). In an audit o 47 pregnancies in women with

pulmonary hypertension at Parkland Hospital, the maternal

mortality rate was 9 percent (Herrera, 2020). O our deaths,

three women had severe hypertension. A striking example o

right ventricular hypertrophy in one o these women who died

is shown in Figure 52-6.

Pregnancy is contraindicated with severe disease. Tis is

especially true in women with pulmonary arterial changes,

which develop in most group 1 cases. With milder disease rom

other causes—group 2 being the most common—the prognosis is better. With the more requent use o echocardiography

and pulmonary artery catheterization in young women withCardiovascular Disorders 931

CHAPTER 52

TABLE 52-8. Comprehensive Clinical Classification of Pulmonary Hypertension of the European Society of Cardiology

and the European Respiratory Society

1. Pulmonary arterial hypertension

Idiopathic

Heritable

Drug and toxin induced

Associated with connective tissue disease, HIV infections, portal hypertension, congenital heart diseases, schistosomiasis

I’ Pulmonary venoocclusive disease and/or pulmonary capillary hemangiomatosis

Idiopathic

Heritable

Drugs, toxins and radiation induced

Associated with connective tissue disease, HIV infection

I” Persistent pulmonary hypertension of the newborn

2. Pulmonary hypertension due to left heart disease

Left ventricular systolic dysfunction

Left ventricular diastolic dysfunction

Valvular disease

Congenital/acquired left heart inflow/outflow tract obstruction and congenital cardiomyopathies

Congenital/acquired pulmonary vein stenosis

3. Pulmonary hypertension due to lung diseases and/or hypoxia

Chronic obstructive pulmonary disease

Interstitial lung disease

Other pulmonary diseases with mixed restrictive and obstructive pattern

Sleep-disoriented breathing

Alveolar hypoventilation disorder

Chronic exposure to high altitude

Developmental lung diseases

4. Chronic thromboembolic pulmonary hypertension/other pulmonary artery obstructions

Chronic thromboembolic pulmonary hypertension

Other pulmonary artery obstructions, i.e., tumors, arteritis, pulmonary stenosis, parasites

5. Pulmonary hypertension with unclear and/or multifactorial mechanisms

Hematological disorders: chronic hemolysis, myeloproliferative disorders, splenectomy

Systemic disorders: sarcoidosis, pulmonary histiocytosis, neurofibromatosis

Metabolic disorders: glycogen storage disease, Gaucher disease, thyroid disorders

Others: fibrosing mediastinitis, chronic renal failure

HIV = human immunodeficiency virus.

Adapted from Galiè, 2016.

FIGURE 52-6 Cross-sectional display of right cardiac dysmorphology in a pregnant woman who died from undiagnosed primary

pulmonary hypertension. There is prominent dilation of the right

ventricle with right ventricular hypertrophy (arrow).

heart disease, we have identied women with mild to moderate pulmonary hypertension who tolerate pregnancy, labor, and

delivery well (Herrera, 2020).

■ Management

reatment o symptomatic pregnant women includes limiting

activity and avoiding supine position later in gestation. Diuretics, supplemental oxygen, and pulmonary vasodilator drugs are

standard therapy or symptoms. Some recommend anticoagulation. Several reports describe the successul use o intravenous

pulmonary artery vasodilators (Foeller, 2018; Franco, 2019).

Prostacyclin analogues that can be administered parenterally

include epoprostenol (Flolan) and treprostinil (Remodulin),

whereas iloprost (Ventavis) is inhaled. Each has been used

in pregnancy. Inhaled nitric oxide is an option that has been932 Medical and Surgical Complications

Section 12

employed in cases o acute cardiopulmonary decompensation.

As reviewed by Običan and Cleary (2014), phosphodiesterase-5 inhibitors, such as sildenal (Viagra), cause vasodilation

o both the pulmonary and systemic vascular beds and have an

inotropic eect on the hypertrophic right ventricle. Tis also

has been used to advantage during pregnancy (Meng, 2017).

Bosentan—an endothelin-receptor antagonist, and riociguat—

a soluble guanylate cyclase stimulator, are teratogenic in mice

and contraindicated in pregnancy (Franco, 2019).

During labor and delivery, supplemental oxygen is given to

maintain >90 percent saturation. Tese women are at greatest

risk when venous return and right ventricular lling are diminished. o avoid hypotension, assiduous attention is given to

epidural analgesia induction, uid therapy, and blood loss

prevention and treatment at delivery (Martin, 2019; Meng,

2017).

CARDIOMYOPATHIES

Te American Heart Association denes these as a heterogeneous group o myocardial diseases associated with mechanical

and/or electrical dysunction (Narula, 2017). Aected women

usually have inappropriate ventricular hypertrophy or dilation.

Cardiomyopathies stem rom varied causes, and the most requent is genetic. O the two major divisions, primary cardiomyopathies are solely or predominantly conned to the heart

muscle. Examples are hypertrophic cardiomyopathy, dilated

cardiomyopathies, and peripartum cardiomyopathy. Secondary

cardiomyopathies result rom generalized systemic disorders that

produce pathological myocardial involvement. Diabetes, systemic lupus erythematosus, chronic hypertension, and thyroid

disorders are representative conditions.

■ Hypertrophic Cardiomyopathy

Tis disorder aects approximately 1 in 500 adults (Herrey, 2014).

Characterized by cardiac hypertrophy, myocyte disarray, and interstitial brosis, the condition in up to 60 percent o aected patients

is caused by mutations in genes that encode cardiac sarcomere

proteins. In such cases, inheritance is autosomal dominant, and

genetic screening is complex (Cirino, 2019; Elliott, 2014). Other

genetic and nongenetic etiologies underlie 5 to 10 percent o cases,

and the cause is unknown in approximately 25 percent. Te resulting myocardial muscle abnormality is typied by let ventricular

myocardial hypertrophy with a pressure gradient against let ventricular outow. Diagnosis is established by echocardiographic

identication o a hypertrophied and nondilated let ventricle in

the absence o other cardiovascular conditions.

Most aected women are asymptomatic, but dyspnea, anginal

or atypical chest pain, syncope, and arrhythmias may develop.

Complex arrhythmias may progress to sudden death, which is

the most requent cause o death. Asymptomatic patients with

runs o ventricular tachycardia are especially prone to sudden

death. Symptoms usually worsen with exercise.

Studies that include more than 700 pregnancies in 500 women

indicate an overall relatively good prognosis (Schauelberger,

2019). In a systematic review with 237 women with hypertrophic cardiomyopathy who had a combined 408 pregnancies,

the maternal mortality rate was 0.5 percent (Schinkel, 2014).

Worsening o symptoms or other complications developed in

29 percent, and 26 percent delivered preterm.

Management is similar to that or aortic stenosis (p. 926).

Controlling heart rate and avoiding preload and aterload reduction are therapy basics. Strenuous exercise is prohibited during

pregnancy. Abrupt positional changes are avoided to prevent

reex vasodilation and decreased preload. I symptoms develop,

especially angina, β-adrenergic or calcium-channel blocking

drugs are given. Drugs that evoke diuresis or reduce vascular resistance are generally not used because they decrease preload. But

i these are necessary, women should be closely monitored. Te

delivery route is determined by obstetrical indications. Choice o

anesthesia is controversial, and some consider general anesthesia

the saest. Regional analgesia can be used with careully titrated,

adequate intravascular volume to maintain let ventricular lling

pressure. Neonates rarely demonstrate inherited lesions at birth.

■ Dilated Cardiomyopathy

Tis is characterized by let and/or right ventricular enlargement

and reduced systolic unction in the absence o coronary, valvular, congenital, or systemic disease known to cause myocardial

dysunction. Although there are many known inherited and

acquired causes o dilated cardiomyopathy, the etiology remains

undened in approximately hal o cases (Schauelberger, 2019).

Some result rom viral inections, including myocarditis and HIV.

Other causes, which are potentially reversible, include alcoholism, cocaine abuse, coronavirus disease 2019 (COVID-19),

and thyroid disease.

In aected gravidas, the rate o major adverse cardiovascular

events in pregnancy ranges rom 25 to 40 percent (American College o Obstetricians and Gynecologists, 2019; Grewal, 2009).

Heart ailure and arrhythmias are the most common, and women

with preexisting moderate or severe let ventricular dysunction or

NYHA unctional class III or IV are at greatest risk. Dilated cardiomyopathy is managed with therapy or standard heart ailure

and or the specic underlying etiology (Bozkurt, 2016).

■ Peripartum Cardiomyopathy

Tis disorder is similar to other orms o nonischemic dilated

cardiomyopathy except or its unique relationship with pregnancy. Peripartum cardiomyopathy shares a genetic predisposition with both amilial and sporadic idiopathic dilated

cardiomyopathy (Cunningham, 2019; Ware, 2016). It is a

diagnosis o exclusion ollowing a concurrent evaluation or

peripartum heart ailure.

Although the term peripartum cardiomyopathy has been

used widely, until recently, little evidence supported a unique

pregnancy-induced cardiomyopathy. Pearson (2000) reported

ndings o a workshop o the National Heart, Lung, and Blood

Institute that established the ollowing diagnostic criteria:

Development o cardiac ailure in the last month o pregnancy or within 5 months ater delivery (Fig. 52-7),

• Absence of an identiable cause for the cardiac failure,

• Absence of recognizable heart disease prior to the last month

o pregnancy, andCardiovascular Disorders 933

CHAPTER 52

• Left ventricular systolic dysfunction demonstrated by classic

echocardiographic criteria. Tese include depressed ejection

raction or ractional shortening along with a dilated let

ventricle.

Te incidence o peripartum cardiomyopathy varies considerably and depends on the population studied and the diligence

o the search or a cause. Te average requency in the United

States is 1 per 1000 to 4000 births (Cruz, 2018; Cunningham,

2019).

Te etiology o peripartum cardiomyopathy remains

unknown, and proposed causes include viral myocarditis,

abnormal immune response to pregnancy, aberrant response to

the greater hemodynamic burden o pregnancy, hormonal interactions, malnutrition, inammation, and apoptosis. Te current

theory regarding pathophysiology is that o a “two-hit hypothesis” (Cruz, 2018; Ricke-Hoch, 2020). In this regard, peripartum cardiomyopathy aects genetically susceptible women who

have one o several cardiac gene mutations to include TTNC1,

TTN, and STAT3. Pregnancy at term is urther characterized by

prodigious secretion o prolactin by the maternal pituitary. At

the same time, the placenta secretes high levels o the antiangiogenic molecule soluble ms-like tyrosine kinase (sFlt-1). Although

a number o putative triggering events have been hypothesized,

a 16-kDa prolactin ragment—vasoinhibin—acts to cause myocardial damage with clinically apparent ventricular dysunction.

Tis is made worse by high levels o sFlt-1, which is superabundant in women with preeclampsia, multietal pregnancy,

or both. Bromocriptine therapy has been evaluated because it

inhibits prolactin secretion, and preliminary studies support its

use (Haghikia, 2019). For the same reason, it is also reasonable

to proscribe breasteeding.

Hypertensive disorders requently coexist with peripartum

cardiomyopathy, and another proposed mechanism links peripartum cardiomyopathy to preeclampsia (Cunningham, 2019).

Antiangiogenic actors are known to be associated with preeclampsia and can induce peripartum cardiomyopathy in susceptible mice. Tus, cardiomyopathy may be precipitated by

antiangiogenic actors in a genetically predisposed host because

o insufcient proangiogenic actors.

Ntusi and coworkers (2015) analyzed the clinical eatures

o women with peripartum cardiomyopathy compared with

those with hypertensive heart ailure. All women with peripartum cardiomyopathy became symptomatic in the postpartum

period, whereas 85 percent o women with hypertensive heart

ailure developed symptoms antepartum. Peripartum cardiomyopathy was signicantly linked with twin gestation, smoking,

and echocardiographic abnormalities. In contrast, hypertensive

heart ailure patients more oten had a amily history o hypertension, hypertension and preeclampsia in a prior pregnancy,

and let ventricular hypertrophy.

Management

Management o peripartum cardiomyopathy is the same as that

o heart ailure, and described earlier (p. 922). Terapy is aimed

at volume overload, aterload reduction, rhythm control, and

inotropic support (Davis, 2020). In addition, β-blocker therapy is used to decrease mortality rates. Anticoagulation with

LMWH is considered when the ejection raction reaches 30

to 35 percent because o the increased risk or let ventricular

thrombi (Bauersachs, 2016; Bozkurt, 2016).

In one pilot study, bromocriptine resulted in higher rates o

let ventricular recovery at 6 months and lower mortality rates

(Sliwa, 2010). A larger study o 115 women showed no di-

erence in ull restoration o let ventricular unction between

those treated and untreated with bromocriptine (Haghikia,

2013). Another investigation o 63 women showed no dierence in let ventricular unction improvement with short-term

versus long-term bromocriptine therapy (Hilker-Kleiner,

2017). Te use o bromocriptine as adjuvant therapy is considered experimental at this time.

Prognosis

Approximately hal o women suering rom peripartum cardiomyopathy recover baseline ventricular unction within

6 months o delivery. Tis rate is lower in obese women (Davis,

2018). In a group o 100 women with newly diagnosed peripartum cardiomyopathy, 72 percent had a let ventricular ejection

raction ≥50 percent at 1 year postpartum (McNamara, 2015).

Recovery to this level occurred in almost 90 percent o women

whose baseline ejection raction was at least 30 percent. Tis

is compared with <40 percent in women whose baseline ventricular ejection raction was <30 percent. Recovery was also

related to the baseline let ventricular end-diastolic diameter.

Event-ree survival at 1 year occurred in 93 percent. Six women

experienced nine major events that included our deaths, our

let ventricular assist device implantations, and one heart transplantation. Li and colleagues (2016) also ound that a baseline

let ventricular ejection raction <34 percent and a BNP level

>1860 pg/mL were associated with an approximately three-

old greater risk o persistent let ventricular systolic dysunction. Te mortality rate approaches 5 to 10 percent at 1 year

in women with persistent cardiac ailure (American College o

Obstetricians and Gynecologists, 2019).

Long-term ollow-up was reported in 28 women with a

median surveillance o 91 months (Ersbøll, 2018). Although

FIGURE 52-7 Peripartum cardiomyopathy with mild pulmonary edema. Chest radiograph of a woman with an abnormally

enlarged heart and mild perihilar opacification consistent with

dilated cardiomyopathy.934 Medical and Surgical Complications

Section 12

most women were asymptomatic, compared with controls, they

had lower ejection ractions, less maximal exercise capacity, and

subtle diastolic dysunction.

Subsequent Pregnancy

From the largest studies on the topic, approximately a third

o women with a history o peripartum cardiomyopathy will

suer relapse with worsening o symptoms and deterioration o

let ventricular unction during another pregnancy (Elkayam,

2014a). Te risk o relapse in women with persistent let ventricular dysunction is substantially higher than in those who

have recovered normal ventricular unction beore a subsequent

pregnancy (Hilker-Kleiner, 2017). However, normalization o

let ventricular unction does not guarantee an uncomplicated

pregnancy, because approximately 20 percent o these women

are at risk or deterioration in that unction (Codsi, 2018).

■ Other Cardiomyopathy Types

Arrhythmogenic right ventricular dysplasia is a unique cardiomyopathy dened histologically by progressive replacement

o right ventricular myocardium with adipose and brous tissue. It has an estimated population prevalence o 1 in 5000,

predisposes to ventricular tachyarrhythmias, and is a cause o

sudden death, particularly in younger individuals (Agir, 2014).

Studies o pregnancies in aected women reported symptoms,

including heart ailure, in 18 to 33 percent o pregnancies

(Schauelberger, 2019). Based on their systematic review, Krul

and coworkers (2011) counsel against pregnancy.

Restrictive cardiomyopathy is probably the least common

type. Tis inherited cardiomyopathy is characterized by a ventricular lling pattern in which worsening myocardial stiness

raises ventricular pressure precipitously and allows only a small

lling volume (Elliott, 2008). Pregnancy is not advised because

o the severe clinical course and poor prognosis in general.

Takotsubo cardiomyopathy is a rare orm o acute reversible

let ventricular apical wall ballooning (Krat, 2017). It is considered to be “stress induced” and appears to be more common

with preeclampsia and cesarean delivery. Myocardial inarction

must be excluded (Oindi, 2019).

INFECTIVE ENDOCARDITIS

Persons at greatest risk or endocarditis are those with congenital heart lesions, intravenous drug use, degenerative valve

disease, and intracardiac devices (Karchmer, 2018). Subacute

bacterial endocarditis usually stems rom a low-virulence bacterial inection superimposed on an underlying structural lesion.

Tese are usually native valve inections. Organisms that cause

indolent endocarditis are most oten viridans-group streptococci or Staphylococcus or Enterococcus species. Among intravenous drug abusers and those with catheter-related inections,

Staphylococcus aureus predominates. With prosthetic valve

inections, Staphylococcus epidermidis is a requent cause. Streptococcus pneumoniae and Neisseria gonorrhoeae may occasionally

cause acute, ulminating disease. Others have reported other

Neisseria species, group B streptococcus, and Escherichia coli

endocarditis during pregnancy or peripartum.

■ Diagnosis and Management

Inective endocarditis symptoms vary and oten develop insidiously. Fever, oten with chills, is seen in 80 to 90 percent o

cases; a murmur is heard in up to 85 percent; and anorexia,

atigue, and other constitutional symptoms are common

(Karchmer, 2018). Clinical clues are anemia, proteinuria, and

maniestations o embolic lesions that include petechiae, ocal

neurological changes, chest or abdominal pain, and extremity

ischemia. In some cases, heart ailure develops. Symptoms may

persist or several weeks beore the diagnosis is ound, and a

high index o suspicion is necessary.

Diagnosis is made using the Duke-Li classication, which

combines microbiology and imaging criteria with ve minor

criteria (Iung, 2019). Echocardiography may be diagnostic, but

lesions <2 mm or those on the tricuspid valve may be missed.

I uncertain, transesophageal echocardiography is accurate and

inormative. Importantly, a negative echocardiographic study

does not exclude endocarditis.

reatment is primarily medical, and ascertainment o the

inecting organism and its sensitivities is imperative or antimicrobial selection. Guidelines or appropriate antibiotic

treatment are published by proessional societies and updated

regularly (Habib, 2015; Karchmer, 2018). Recalcitrant bacteremia and heart ailure due to valvular dysunction are a

ew reasons or which persistent inection may require valve

replacement (Iung, 2019).

■ Pregnancy

Inective endocarditis is uncommon during pregnancy and

the puerperium. In an earlier period, the incidence o endocarditis at Parkland Hospital approximated 1 in 16,000 births

(Cox, 1988). With the current opioid use disorder epidemic,

endocarditis may become more requent (Prasad, 2019).

Associated maternal and etal mortality rates are rom 25 to

35 percent (Dagher, 2021; Habib, 2015). In one review, risk

actors were intravenous drug use (14 percent), congenital heart

disease (12 percent), and rheumatic heart disease (12 percent).

Te most common pathogens were streptococcal (43 percent)

and staphylococcal (26 percent) species. Among 51 pregnancies, the maternal mortality rate was 11 percent (Kebed, 2014).

■ Endocarditis Prophylaxis

For years, patients with any heart valve problem were given periprocedural antibiotics or endocarditis prophylaxis. Currently,

however, recommendations are more stringent. Te American

Heart Association recommends prophylaxis or dental procedures in those with: (1) a prosthetic valve or prosthetic material

used in a valve repair, (2) prior endocarditis, (3) unrepaired

cyanotic heart deect or repaired lesion with residual deect at

prosthetic sites, and (4) valvulopathy ater heart transplantation (Nishimura, 2017). In the absence o pelvic inection, the

American College o Obstetricians and Gynecologists (2018b)

does not recommend endocarditis prophylaxis or either vaginal or cesarean delivery, except with the lesions cited above.

Pregnant women at highest risk or endocarditis are

those with cyanotic cardiac disease, prosthetic valves, or both.Cardiovascular Disorders 935

CHAPTER 52

Table 52-9 shows prophylactic regimens or women not already

receiving intrapartum antimicrobial therapy or another indication that would also provide coverage against endocarditis.

Tese are administered as close to 30 to 60 minutes beore the

anticipated delivery time as is easible.

ARRHYTHMIAS

Both preexisting and new-onset cardiac arrhythmias are oten

encountered during pregnancy, labor, delivery, and the puerperium. Tey are usually benign and their incidence in pregnancy

appears to be increasing (MacIntyre, 2018). Te mechanism(s)

responsible or the higher incidence are not clear. From some

studies, estradiol and progesterone are proarrhythmic. Estrogen augments the number o adrenergic receptors in the myocardium, and adrenergic responsiveness seems to be greater

in pregnancy (Enriquez, 2014). Perhaps the normal but mild

hypokalemia o pregnancy and/or the physiological rise in heart

rate serves to induce arrhythmias. Alternatively, detection o

arrhythmias may be greater because o the requent visits in

routine prenatal care.

■ Bradyarrhythmias

Slow heart rhythms, including complete heart block, are compatible with a successul pregnancy outcome (Keepanasseril,

2015). Some women with complete heart block have syncope

during labor and delivery, and occasionally temporary cardiac

pacing is necessary. In our experiences and rom others, women

with permanent articial pacemakers usually tolerate pregnancy

well (Hidaka, 2011). With xed-rate devices, cardiac output

apparently is increased by augmented stroke volume.

Patients with pacemakers or other electrical implants require

special precautions during surgery. Stray current may be interpreted as an intracardiac signal by the implanted device and

lead to pacing changes. In addition, myocardial burns may

result rom conduction o electrosurgical current to the pacing

electrode rather than to the grounding pad. With these devices,

preventive steps include cardiology consultation; bipolar electrosurgery or Harmonic scalpel use rather than monopolar

current; i needed, minimal monopolar settings; continuous

cardiac and pulse oximetry monitoring; contingency plans

or arrhythmias; and close proximity o active (electrosurgical

pencil) and return (electrosurgical grounding pad) electrodes

(Crossley, 2011).

■ Supraventricular Tachycardias

Te most common arrhythmia seen in reproductive-aged women

is paroxysmal supraventricular tachycardia (SVT). Te prevalence

during pregnancy is 24 cases per 100,000 hospital admissions,

and approximately 20 percent will experience symptomatic exacerbations during pregnancy (Enriquez, 2014). Interestingly, the

mean heart rate o pregnant women with paroxysmal SV is 184

bpm compared with 166 bpm in nonpregnant aected women

(Yu, 2015). In one study, approximately hal o women with

paroxysmal SV had an initial onset during pregnancy (Bánhidy, 2015). Notably, maternal paroxysmal SV was associated

with a twoold higher risk o septal cardiac deects, particularly

secundum atrial septal deects, in their ospring.

For acute SV treatment, vagal maneuvers, which include

Valsalva maneuver, carotid sinus massage, bearing down, and

immersion o the ace in ice water, raise vagal tone and block

the atrioventricular node. Intravenous adenosine is a shortacting endogenous nucleotide that also blocks AV nodal conduction. Our experiences are similar to those o others in that

adenosine is sae and eective or cardioversion in hemodynamically stable gravidas (Page, 2015). ransient etal bradycardia

has been described with adenosine (Dunn, 2000).

I pharmacological therapy is ineective or contraindicated,

the American College o Cardiology and the American Heart

Association recommend synchronized cardioversion in pregnant

women with hemodynamically unstable SV (Page, 2015).

Although electrical cardioversion with standard energy settings is

not contraindicated in pregnancy, vigilance is important. Barnes

and colleagues (2002) described a case in which direct current

cardioversion led to a sustained uterine contraction and etal bradycardia. As an aside, pregnancy has no eect on the operation

o implantable cardioverter-debrillator devices (Boulé, 2014).

I cardioversion ails or is unsae because o concurrent thrombus, then long-term anticoagulation and heart rate control with

medication are necessary (DiCarlo-Meacham, 2011). Other treatment options recommended by the American College o Cardiology and the American Heart Association (Page, 2015) include:

• Intravenous metoprolol or propranolol when adenosine is

ineective or contraindicated,

TABLE 52-9. Single-Dose Antibiotic Prophylaxis for Infective Endocarditis in High-Risk Patients

American College of Obstetricians and Gynecologists (2018b)

Standard (IV): ampicillin 2 g or cefazolin or ceftriaxone 1 g

Penicillin-allergic (IV): cefazolin or ceftriaxone 1 g or clindamycin 600 mg

Oral: amoxicillin 2 g

American Heart Association/European Society of Cardiology (Karchmer, 2018)

Standard: amoxicillin 2 g PO or ampicillin 2 g IV or IM

Penicillin-allergic: clarithromycin or azithromycin 500 mg PO; cephalexin 2 g PO; clindamycin

600 mg PO, IV, or IM; or cefazolin or ceftriaxone 1 g IV or IM

IM = intramuscularly; IV = intravenously; PO = per os (orally).

Cefazolin or ceftriaxone given 30 minutes, and all others given 1 hour prior to procedure.936 Medical and Surgical Complications

Section 12

• Intravenous verapamil when adenosine and β-blocking

agents are ineective or contraindicated,

• Intravenous procainamide,

• Intravenous amiodarone for potentially life-threatening SVT

and when other therapies are ineective or contraindicated.

Atrial brillation and atrial utter rarely present or the rst

time during pregnancy. A new-onset atrial brillation should

prompt a search or underlying etiologies that include cardiac

anomalies, hyperthyroidism, pulmonary embolism, drug toxicity, and electrolyte disturbances (MacIntyre, 2018). Major

complications include embolic stroke. When associated with

mitral stenosis, pulmonary edema may develop in later pregnancy i the ventricular rate is increased. Unstable patients are

treated with cardioversion and rate control.

Pregnancy may predispose otherwise asymptomatic women

with Wolf-Parkinson-White (WPW) syndrome to exhibit arrhythmias. In a study o women with asymptomatic or mildly symptomatic disease, hal developed SV or the rst time, and the

other hal experienced an increase in their attack rate (Kounis,

1995). In some patients, accessory pathway ablation may be indicated. Patients with Ebstein anomaly are prone to have WPW

syndrome. Driver and associates (2015) have provided a review.

■ Ventricular Tachycardia

Tis orm o arrhythmia is uncommon but potentially atal in

healthy young women without underlying heart disease. Brodsky and coworkers (1992) described seven pregnant women

with new-onset ventricular tachycardia and reviewed 23

reports. Most o these women were not ound to have structural heart disease. In 14 cases, tachycardia was precipitated by

physical exercise or psychological stress. Abnormalities ound

included two cases o myocardial inarction, two o prolonged

Q interval, and one o anesthesia-provoked tachycardia. Tey

concluded that pregnancy events precipitated the tachycardia

and recommended β-blocking agents or control. As previously discussed (p. 934), arrhythmogenic right ventricular dysplasia will result occasionally in ventricular tachyarrhythmias.

I unstable, emergency cardioversion is indicated, and standard

adult energy settings are adequate (Lin, 2015).

■ Prolonged QTInterval

Te long QT syndrome is the most requent inherited channelopathy (MacIntyre, 2018). Tis conduction anomaly may predispose individuals to a potentially atal ventricular arrhythmia

known as torsades de pointes. wo studies comprised o 502

pregnant women with long Q syndrome both reported a

signicant rise in cardiac events postpartum but not during

pregnancy (Rashba, 1998; Seth, 2007). Te normal elevation

in heart rate during pregnancy may be partially protective.

Paradoxically, β-blocking agents—preerably propranolol—

lower the risk o torsades de pointes in patients with long Q

syndrome and should be continued throughout pregnancy

and the puerperium (Ishibashi, 2017). Importantly, many

medications, including some used during pregnancy, such

as the erythromycins and many antiemetics, may predispose

to Q prolongation. For opioid-addicted women, the use o

methadone to treat withdrawal symptoms may be problematic

(Bogen, 2017). Last, Cuneo and colleagues (2020) observed an

eightold risk or stillbirth in women with long Q syndrome

(Chap. 35, p. 624).

DISEASES OF THE AORTA

■ Aortic Dissection

Maran syndrome and coarctation are two aortic diseases that

place the pregnant woman at greater risk or aortic dissection (Russo, 2017). Indeed, hal o dissection cases in young

women are related to pregnancy (O’Gara, 2004). Other risk

actors are bicuspid aortic valve and urner, Noonan, LoeysDietz, or Ehlers-Danlos syndrome (Cauldwell, 2019b; Russo,

2018). Pregnancy-related cardiac guidance or women with

urner syndrome is outlined in Chapter 3 (p. 37). Although

the mechanism(s) involved are unclear, the initiating event is a

tear in the intimal layer o the aorta, ollowed by hemorrhage

into the media, and nally rupture.

In most cases, aortic dissection presents with severe chest

pain described as ripping, tearing, or stabbing. Diminution or

loss o peripheral pulses coupled with a recently acquired aortic insufciency murmur is an important physical nding. Te

dierential diagnosis o aortic dissection in pregnancy includes

myocardial inarction, pulmonary embolism, pneumothorax,

aortic valve rupture, and obstetrical catastrophes such as placental abruption and uterine rupture.

More than 90 percent o patients with aortic dissection have

an abnormal chest radiograph. Aortic angiography is the most

denitive method or diagnosis conrmation. However, sonography, computed tomography, and MR imaging are used more

requently depending on the clinical urgency.

Initial medical treatment is given to lower blood pressure.

Proximal dissections most oten need to be resected, and the

aortic valve replaced i necessary. Distal dissections are more

complex, and many may be treated medically. Among nonpregnant patients with abdominal aortic aneurysms <5.5 cm, survival is not improved by immediate elective repair compared

with surveillance and delayed repair. Karthikesalingam and

associates (2016) suggest that the size threshold or aneurysm

repair should be revisited.

■ Marfan Syndrome

Tis autosomal dominant connective tissue disorder has an

incidence o 1 per 3000 to 5000 individuals and is without

racial or ethnic predilection (Azizad-Pinto, 2017). As discussed

in Chapter 62 (p. 1121), Maran syndrome is caused by any

o more than 1000 mutations in the brillin (FBN1) gene. It

is characterized by generalized tissue weakness that can result

in dangerous cardiovascular complications. All tissues are

involved, and other requent deects include joint laxity and

scoliosis. Progressive aortic dilation causes aortic valve insufciency, and inective endocarditis or mitral valve prolapse with

insufciency may be comorbid. Aortic dilation and dissecting

aneurysm are the most serious abnormalities. Early death is due

to either a dissecting aneurysm or to valvular insufciency and

heart ailure.Cardiovascular Disorders 937

CHAPTER 52

During pregnancy, the primary concern with Maran syndrome is aortic dissection (Curry, 2014; Russo, 2017). A

study using the Nationwide Inpatient Sample rom 2003 to

2010 described 339 deliveries in women with Maran syndrome. Tere was one maternal death and six (1.8 percent)

aortic dissections (Hassan, 2015). From the United Kingdom,

Cauldwell and colleagues (2019a) described 258 pregnancies

in 151 aected women. Although no women died, 1.9 percent

had an aortic dissection.

Te aortic root usually measures approximately 2 cm, and

during normal pregnancy, it expands slightly. With Maran

syndrome, aortic root repair is recommended at diameters

o 4.0 to 4.5 cm (Azizad-Pinto, 2017). Te guidelines o the

American College o Cardiology, the American Heart Association, and the American Association o Toracic Surgeons advise

prophylactic aortic repair in women considering pregnancy i

the diameter o the ascending aorta exceeds 4 cm (Hiratzka,

2010). Te guidelines o the European Society o Cardiology advise repair o the aorta at diameters >4.5 cm (RegitzZagrosek, 2018). Surgical repair is also considered using a

ormula indexed to height because shorter patients have dissection at a smaller diameter (Bradley, 2014).

For pregnant women with known thoracic aortic root or

ascending aortic dilation, monthly or bimonthly echocardiographic measurements o the ascending aortic dimensions are

recommended to detect expansion (American College o Obstetricians and Gynecologists, 2019). Prophylactic β-blocking

agents have become standard or gravidas with Maran syndrome because they reduce hemodynamic stress on the ascending aorta and slow the dilation rate. Ideally, pregnant women

with aortic aneurysms are delivered at acilities in which cardiothoracic surgery is available. Vaginal delivery with regional

analgesia and an assisted second stage seem sae or women with

an aortic root diameter <4 cm.

Cesarean delivery may be considered or values between 4.0

and 4.5 cm. When the aortic root measures >4.5 cm, elective

cesarean delivery is recommended, and direct replacement o

the proximal aorta with a prosthetic grat can be considered

(Regitz-Zagrosek, 2018). Successul aortic root replacement

during pregnancy has been described, but the surgery has also

been associated with etal hypoxic-ischemic encephalopathy

(Seeburger, 2007). Several case reports describe emergency

cesarean deliveries in women with acute type A dissections that

were repaired successully at the time o delivery (Guo, 2011;

Haas, 2011; Papatsonis, 2009).

o evaluate obstetrical outcomes, investigators or one study

o 63 women with Maran syndrome analyzed their 142 pregnancies. O 111 pregnancies progressing past 20 weeks’ gestation, 15 percent delivered preterm, and 5 percent had preterm

prematurely ruptured membranes (Meijboom, 2006). Tere

were eight perinatal deaths, and hal o the neonatal survivors

were subsequently diagnosed with Maran syndrome.

■ Aortic Coarctation

In this relatively rare lesion, the aorta is abnormally narrowed

and is oten accompanied by abnormalities o other large arteries. A ourth o aected patients have a bicuspid aortic valve,

and another 10 percent have cerebral artery aneurysms. Other

associated lesions are persistent ductus arteriosus, septal deects,

and urner syndrome. Te collateral circulation arising above

the coarctation remodels and expands, oten strikingly, to cause

localized erosion o rib margins by hypertrophied intercostal

arteries. ypical ndings include hypertension in the upper

extremities but normal or decreased pressures in the lower

extremities. Some have described diagnosis during pregnancy

using MR imaging (Sherer, 2002; Zwiers, 2006). Jimenez-Juan

and associates (2014) ound that aortic diameter measured by

MR imaging and the risk o adverse events during pregnancy

were inversely correlated. O note, no adverse outcomes occurred

i the minimum diameter at the coarctation exceeded 15 mm.

Major complications with aortic coarctation include congestive heart ailure ater long-standing severe hypertension, bacterial endocarditis o an associated bicuspid aortic valve, and

aortic rupture. Antihypertensive therapy using β-blocking drugs

is usually required because hypertension may worsen in pregnancy. Aortic rupture is more likely late in pregnancy or early

puerperium. Cerebral hemorrhage rom circle o Willis aneurysms

also may occur. According to the World Health Organization,

severe coarctation should preclude pregnancy (Foeller, 2018).

In one study o outcomes rom 188 pregnancies, a third

o women had hypertension that was related to signicant

coarctation gradients, and one woman died rom dissection

at 36 weeks’ gestation (Beauchesne, 2001). In 700 deliveries

complicated with coarctation, hypertensive complications o

pregnancy were increased three- to ourold (Krieger, 2011).

Importantly, almost 5 percent o women with coarctation had

an adverse cardiovascular outcome—maternal death, heart

ailure, arrhythmia, cerebrovascular or other embolic event—

compared with only 0.3 percent o controls. O women with

coarctation, 41 percent underwent cesarean delivery compared

with 26 percent o controls.

Congestive heart ailure demands vigorous eorts to improve

cardiac unction and may warrant pregnancy interruption. In

this setting, some authors recommend that resection o the

coarctation be undertaken to protect against the possibility o

a dissecting aneurysm and aortic rupture. Tis poses signicant

perusion risk, especially or the etus, because all the arterial

collaterals must be clamped or variable periods.

ISCHEMIC HEART DISEASE

Pregnant women with coronary artery disease commonly have

the classic risk actors o amily history, diabetes, smoking,

hypertension, hyperlipidemia, and obesity (ripathi, 2019).

Te rate o ischemic heart disease is estimated to be 10 cases per

100,000 pregnancy and postpartum hospitalizations (Smilowitz, 2018; ripathi, 2019). Although relatively rare, the risk o

acute myocardial inarction is approximately threeold higher

in pregnant women compared with nonpregnant women o

similar age (Elkayam, 2014b).

■ Acute Coronary Syndrome

Myocardial inarction (MI) is the end result o an acute coronary

syndrome. It can result rom coronary artery atherosclerosis,938 Medical and Surgical Complications

Section 12

dissection, embolism, spasm, or arteritis (American College o

Obstetricians and Gynecologists, 2019; Cauldwell, 2020). Te

mortality rate with MI in pregnancy is higher compared with

age-matched nonpregnant women. In a Nationwide Inpatient

Sample study totaling 859 pregnancies complicated by acute

MI, the death rate was 5.1 percent (James, 2006). Women who

sustain an inarction <2 weeks beore delivery are at especially

high risk o death due to the greater myocardial demand o

labor and delivery (Esplin, 1999).

In a systematic review o 150 cases, most women developed an acute MI during the third trimester or postpartum

(Elkayam, 2014b). Approximately three ourths presented with

S segment-elevation MI (SEMI). Te leading mechanisms

o acute inarction included spontaneous coronary dissection (43

percent) and atherosclerotic disease (27 percent). Signicant

complications included heart ailure (38 percent), recurrent

angina or inarction (19 percent), and ventricular arrhythmias

(12 percent). Te maternal and etal mortality rates were 7 and

5 percent, respectively.

Diagnosis o acute coronary syndrome during pregnancy

does not dier rom that in nonpregnant patients and is based

on clinical presentation, characteristic ECG changes, and evidence o myocardial necrosis reected by elevated serum highsensitivity troponin I levels (Pacheco, 2014). Consider that

troponin I levels are greater, however, in preeclamptic and

hypertensive women compared with normotensive gravidas

(Ravichandran, 2019).

With spontaneous coronary artery dissection, establishing

the diagnosis requires an increased index o suspicion in the

women presenting with chest pain (Codsi, 2016). For this

condition, coronary angiography is considered the diagnostic

gold standard and should be expeditiously perormed i acute

coronary syndrome—either MI or unstable angina—is present

(Hayes, 2018).

reatment o acute MI is similar to that or nonpregnant

patients (Pacheco, 2014). Several reports describe successul

percutaneous transluminal coronary angioplasty and stent placement during pregnancy (American College o Obstetricians and

Gynecologists, 2019). Cardiopulmonary resuscitation may be

required, as described in Chapter 50 (p. 897). I the inarct has

healed sufciently, cesarean delivery is reserved or obstetrical

indications, and epidural analgesia is ideal or labor.

■ Pregnancy with Prior Ischemic Heart Disease

Ischemic heart disease is characteristically progressive, and

because it is usually associated with hypertension or diabetes, pregnancy in most o these women seems inadvisable. In

an earlier review o 30 pregnancies in women who had sustained an inarction remote rom pregnancy, none o the women

died, our had congestive heart ailure, and our had worsening angina during pregnancy (Vinatier, 1994). Pombar and

coworkers (1995) evaluated outcomes o women with diabetes-associated ischemic heart disease and inarction. Tree had

undergone coronary artery bypass grating beore pregnancy.

O 17 women, eight died during pregnancy. Certainly, pregnancy raises cardiac workload, and these investigators concluded that ventricular perormance should be assessed using

ventriculography, radionuclide studies, echocardiography, or

coronary angiography beore conception. Without signicant

ventricular dysunction, pregnancy will likely be tolerated. For

the woman who becomes pregnant beore these studies are per-

ormed, echocardiography is done. Exercise tolerance testing

may be indicated, and radionuclide ventriculography exposes

the etus to minimal radiation (Chap. 49, p. 875).

COMMON OBSTETRICAL MEDICATIONS

Common medications used in pregnancy require special consideration in women with cardiac conditions. erbutaline

causes vasodilation and tachycardia, which can be dangerous in

patients with mitral and aortic stenosis. Niedipine or hypertension control or tocolysis results in hypotension that can

have negative consequences or patients with aortic stenosis,

pulmonary hypertension, and Eisenmenger syndrome. Postpartum hemorrhage should be managed aggressively, and methylergonovine generally is a sae choice. Prostaglandin F2α may

cause pulmonary shunting and bronchospasm, which results in

elevation o pulmonary artery pressure. Consideration is given

to the vasodilatory eects o hydralazine in conditions such as

hypertrophic cardiomyopathy. Hydralazine also causes tachycardia. Te β-blocking agent labetalol is a sae choice unless

there is ventricular ailure. In general, oxytocin and magnesium

sulate have minimal cardiac eects

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