Congenital Heart Disease in Pregnancy

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Congenital Heart Disease in Pregnancy

 

Jeannette P. Lin

Key Points

Congenital heart disease (CHD) is the most common congenital defect, affecting approximately 0.8% of live births

Over 80% of patients born with congenital heart disease will survive to adulthood

Aside from bicuspid aortic valves, atrial septal defects (ASDs) are the most common type of congenital heart defect, accounting for 10%–20% of congenital heart defects

A delivery plan readily accessible to all care providers should be outlined for patients who are at moderate or high risk for maternal cardiac complications

Patients with Eisenmenger syndrome are at high risk for maternal morbidity and mortality and therefore pregnancy is contraindicated

 

Introduction

Congenital heart disease (CHD) refers to structural malformations of the heart and/or great vessels that result from abnormal cardiac development in utero or persistence of embryologic structure(s) beyond the first weeks of life (e.g., patent ductus arteriosus). CHD is the most common congenital defect, affecting approximately 0.8% of live births. With improvements in diagnostic tools and advances in surgical and transcatheter techniques, over 80% of patients born with CHD will survive to adulthood. As more women with CHD reach childbearing age, care of these patients requires a multidisciplinary approach with specialists in maternal-fetal medicine, adult CHD, and obstetric anesthesia with expertise in care of this patient population.

When caring for the pregnant patient with CHD, the first step is to identify the patient’s congenital cardiac diagnoses. While some patients have received cardiac care since childhood for their conditions and are well-versed in their diagnoses, others may be unfamiliar with the terminology and unable to name or describe their cardiac condition to their providers. In the latter case, review of imaging and knowledge of CHD may help clarify their diagnoses. While the majority of patients with CHD are diagnosed in childhood, 30% of patients with CHD do not receive their diagnoses of CHD until adulthood. For some, the hemodynamic changes of pregnancy unmask symptoms or murmurs, leading to their congenital cardiac diagnosis.

The second step in caring for the pregnant patient with CHD is to understand their prior congenital cardiac interventions. As Dr. Perloff, one of the founders of the field of adult CHD, eloquently wrote in 1983, nearly all patients with CHD will have either residua or sequelae that warrant lifelong cardiac care [1]. Residua refers to “physiologically unimportant uncorrected defects,” such as bicuspid aortic valve in a patient with coarctation. Sequelae refers to the undesired (but often unavoidable) consequence of a surgical intervention, such as heart block after subaortic stenosis resection. Knowledge of patients’ surgical or procedural history guide surveillance for such residua and sequelae. For example, patients who underwent surgical closure of an atrial septal defect are more likely to have atrial arrhythmias than patients who underwent transcatheter closure of an atrial septal defect due to the presence of atriotomy scars. Finally, providers should seek to understand the patient’s current physiology to guide surveillance and management throughout pregnancy. Although many patients with CHD carry the belief that they were “cured” of their CHD with their childhood surgeries, nearly all patients require lifelong cardiac care [2].

In this chapter, we will review common CHD diagnoses and common residua and sequelae of each defect, and then review the hemodynamic issues often seen in patients with CHD and strategies for management in pregnancy. Table 10.1 outlines a basic checklist for a cardiology or obstetric visit in the pregnant patient with CHD.

Table 10.1

Checklist for CHD Visit in Pregnancy

Past cardiac history

Congenital cardiac diagnosis

Prior surgeries and/or catheter-based interventions

Prior arrhythmias and/or electrophysiology study/ablation

Implantable cardiac device (pacemaker, implantable cardioverter-defibrillator, loop recorder) and device settings

Antiplatelet/anticoagulation, and indication

Current status

Last cardiology visit

Last echocardiogram

Last EKG

Current NHYA functional class

Risk assessment

mWHO class

ZAHARA

CARPREG2

Physiologic stage

Pregnancy management

Add/hold antiplatelet medications or anticoagulation

Echocardiogram frequency

BNP frequency

EKG frequency

CXR frequency

Additional testing

Additional consultations: Maternal-fetal medicine, adult congenital heart disease specialists

Fetal surveillance

Risk for anomalies

Fetal anatomy, including fetal echo

Serial growth

Antepartum fetal heart rate testing

Care of the patient with CHD requires an understanding of the hemodynamic burden of their repaired or unrepaired defect. Hemodynamic burdens can be understood as one or a combination of the following: volume loading, pressure loading, or low cardiac output states (Table 10.2). An overview of common congenital defects and pregnancy management is summarized in Table 10.3.

Table 10.2

Hemodynamic Burdens of Congenital Heart Defects

Hemodynamic Burden

Example(s)

Pregnancy Symptoms

Management Strategies

Comments

Right heart volume loading

Atrial level shunts

Exertional dyspnea, increased lower extremity edema, atrial arrhythmias

Diuretics

Generally well tolerated in pregnancy but may require diuretic therapy

Right heart pressure loading

Pulmonary valve/artery stenosis, double chambered right ventricle

Exertional dyspnea, increased lower extremity edema, ventricular arrhythmias

Diuretics, beta-blockers

Consider transcatheter interventions (balloon angioplasty or valvuloplasty) if refractory symptoms

Left heart volume loading

Mitral or aortic regurgitation

Exertional dyspnea, orthopnea, paroxysmal nocturnal dyspnea, atrial arrhythmias. Ventricular arrhythmias, especially if LV dysfunction

Diuretics, beta-blockers

Generally well tolerated in pregnancy but may require diuretic therapy

Left heart pressure loading

Coarctation of the aorta, aortic stenosis

Exertional dyspnea, orthopnea, paroxysmal nocturnal dyspnea, atrial arrhythmias. Ventricular arrhythmias, especially if LV dysfunction

Diuretics, beta-blockers

Consider transcatheter interventions (balloon angioplasty or valvuloplasty) if refractory symptoms

Table 10.3

An Overview of Common Congenital Defects and Pregnancy Management

Congenital Heart Defect

Hemodynamics

Physical Exam Findings

Findings on Testing

Modified WHO Risk Class

Pregnancy Concerns

Management Recommendation

Unrepaired atrial level shunts (secundum or primum ASDs, sinus venosus defects, unroofed coronary sinus)

Left to right interatrial shunt causes volume loading of the right heart

Right ventricular dysfunction (variable)

Mild-moderately elevated pulmonary artery pressures, particularly in older patients

Split second heart sound

Right ventricular heave

Systolic flow murmur at the left upper sternal border

EKG: incomplete right bundle branch block

Echo: right atrial and right ventricular dilation

Primum or secundum defects usually well visualized by TTE

Sinus venosus defects and unroofed coronary sinus often require TEE, MRI or CT for diagnosis

II

Paradoxical emboli may cause stroke or myocardial infarction

Consider aspirin 81 mg daily

Consider anticoagulation with low molecular weight heparin if patient has a cardioembolic event

SBE prophylaxis at time of delivery is reasonable given potential for transient right to left shunting

Bubble/particle filters on IVs

Unrepaired ventricular septal defect (all types), unrepaired PDA

Small VSD or PDA

No significant hemodynamic impact

Small VSD: holosystolic murmur at the left

sternal border

Small PDA: faint, continuous murmur below the left clavicle

EKG: normal

TTE: small VSD or PDA with high-velocity left to right shunt. Normal chamber sizes

II

No significant additional risk

Small VSDs

SBE prophylaxis reasonable given small risk of endocarditis

Medium-sized VSD or PDA

Pressure loading of the right ventricle

Mild-moderate pulmonary arterial hypertension

Volume loading of the left atrium/left ventricle

Moderate sized VSD: softer holosystolic murmur

RV lift if pulmonary hypertension

Moderate-sized PDA: continuous murmur below the left clavicle

EKG: may demonstrate RV hypertrophy

TTE:

VSD with left to right shunt or PDA with aorta-to-pulmonary artery shunt

Right ventricle hypertrophy and hypertension

Left atrium/ventricle dilation

II-III

Risk for heart failure

Avoid volume loading

Bubble/particle filters on IVs

SBE prophylaxis reasonable given small risk of endocarditis

Left ventricular outflow tract obstruction (subvalvar or supravalvar aortic stenosis)

Pressure loading of the left ventricle

Harsh systolic crescendo murmur at the right upper sternal border

LV impulse may be enlarged if LV hypertrophy is present

EKG: left ventricular hypertrophy

TTE:

Left ventricular hypertrophy

Left atrial dilation if longstanding LVH

Subvalvar aortic stenosis (discrete membrane or tunnel-like) with flow acceleration

Supravalvar aortic stenosis typically at the level of the sinotubular junction

II if moderate stenosis

III if severe obstruction and patient is symptomatic

If severe:

Risk for heart failure

Right for ventricular or atrial arrhythmias

Avoid volume loading

SBE prophylaxis reasonable if aortic valve is thickened

Aortic coarctation

Mild native coarctation, or repaired coarctation without significant residual narrowing

No significant hemodynamic impact

No significant delay between right brachial and femoral pulses

Left upper extremity pulse may be diminished or absent if patient had prior subclavian flap repair

EKG: normal

II

May be prone to hypertension due to aortic stiffness

Avoid checking BP in LUE if prior subclavian flap repair. If unsure whether patient has prior subclavian flap repair, check bilateral upper extremity blood pressures, and follow the higher of the two

Moderate or severe native or residual coarctation

Left ventricular pressure overload

Femoral pulse delayed and diminished compared with (right) upper extremity pulse

LV impulse may be enlarged if LV hypertrophy is present

EKG: left ventricular hypertrophy

III (severe asymptomatic)

IV (severe symptomatic)

Hypertension in the upper body, with relative hypotension of the lower body due to gradient across the coarctation

Risk for heart failure

Monitor upper and lower extremity BPs; placental perfusion will correlate best with LE BPs

Titration of anti-hypertensives as tolerated by mother and fetus

Pain control to avoid fluctuations in blood pressure

Ebsteins anomaly

Right heart volume overload if moderate or severe regurgitation

Right ventricular systolic function often abnormal

Widely split-second heart sound, additional heart sounds common

If ASD is also present, patient may have cyanosis

EKG: right bundle branch block, PR prolongation are common. Evaluate for preexcitation (Wolff- Parkinson-White syndrome)

TTE: right atrial dilation, displaced septal leaflet of the tricuspid valve with elongation of the anterior leaflet, tricuspid regurgitation. Evaluate right ventricular function and assess for secundum ASD

II-III depending on right/left ventricular function, history of arrhythmias, and presence of cyanosis

Risk for atrial arrhythmias (SVT with or without preexcitation, PACs)

Risk for ventricular arrhythmia, especially if poor ventricular function

Risk for paradoxical embolus if ASD is present

Monitor for arrhythmias

Avoid volume loading

Bubble/particle filters if ASD is present

SBE prophylaxis if ASD is present

Pulmonary stenosis, subvalvar pulmonary stenosis, pulmonary artery stenosis

Right heart pressure overload

Systolic crescendo murmur at the left upper sternal border

EKG: right ventricular hypertrophy

TTE: stenosis of subvalvar/valvar/supravalvar region(s); right ventricular hypertrophy; right atrial dilation

I if mild or moderate

II-III if severe

Risk for atrial or ventricular arrhythmias, particularly with severe stenosis

Risk for right heart failure if RV function is decreased

Monitor for arrhythmias

Avoid volume loading

SBE prophylaxis

Tetralogy of Fallot, status post repair

If chronic severe pulmonary valve regurgitation, right heart volume overload

If pulmonary valve is functional, patient may have relatively normal hemodynamics

Fixed split-second heart sound

Short diastolic decrescendo murmur if severe PR

EKG: right bundle branch block

TTE: repaired VSD

Right atrium and right ventricle dilation if chronic severe pulmonary valve regurgitation

II

Right for atrial or ventricular arrhythmias, particularly if history of prior arrhythmias and/or severe RA/RV dilation

Risk for right heart failure if severe RA/RV dilation or severe RV dysfunction

Monitor for arrhythmias

Avoid volume loading

SBE prophylaxis

Double outlet right ventricle, status post Rastelli repair

Truncus arteriosus, status post repair

Variable, depending on presence or absence of residual lesions:

RV-PA conduit stenosis or regurgitation

Aortic regurgitation

Systolic crescendo murmur (flow through RV-PA conduit)

Diastolic decrescendo murmur at the left upper sternal border (RV-PA conduit regurgitation) or right upper sternal border (aortic regurgitation)

EKG: right bundle branch block

TTE: repaired VSD; right atrium and right ventricle size, wall thickness and function dependent on status of the RV-PA conduit

II-III, depending on residual lesions

Variable, depending on residual lesions. If significant RV-PA conduit dysfunction, then increased risk of right heart failure

Avoid volume loading if significant RV-PA conduit dysfunction or severe RV dysfunction

D-Transposition of the great arteries, status post arterial switch

Normal, if no residual lesions

Potential late complications include aortic root dilation, aortic regurgitation, and stenosis of the reimplanted coronary arteries

Normal

EKG: normal

TTE: abnormal positioning of the aorta and pulmonary artery post-arterial switch. LV function normal in most patients

II if no significant residual lesions

Low risk for complications if no significant residual lesions

Low risk for complications if no significant residual lesions

D-Transposition of the great arteries, status post atrial switch procedure

Systemic right ventricle, typically with at least mild systolic dysfunction by adulthood

Tricuspid regurgitation is common, with associated RA/RV volume overload

Right ventricular lift/heave

Holosystolic murmur (tricuspid regurgitation)

EKG: right ventricular hypertrophy

TTE: abnormal position of the aorta (anterior and rightward). Systemic right ventricular systolic function is usually abnormal. Tricuspid regurgitation is common

III if normal or mildly decreased systemic right ventricular function; IV if moderate-severe systemic right ventricular dysfunction

Risk of heart failure

Risk of ventricular and arrhythmias, especially if prior history of arrhythmias

Monitor for arrhythmias

Avoid volume loading

SBE prophylaxis

Congenitally corrected transposition of the great arteries (ccTGA)

Systemic right ventricle, typically with at least mild systolic dysfunction by adulthood

Tricuspid regurgitation is common, with associated RA/RV volume overload

Right ventricular lift/heave

Holosystolic murmur (tricuspid regurgitation)

EKG: right ventricular hypertrophy; q waves in the right precordial leads V1-V2

TTE: leftward systemic right ventricle; Ebsteinoid malformation of the tricuspid valve is associated with ccTGA

III if normal or mildly decreased systemic right ventricular function

IV if moderate-severe systemic right ventricular dysfunction

Risk of heart failure

Risk of ventricular and arrhythmias, especially if prior history of arrhythmias

Monitor for arrhythmias

Avoid volume loading

SBE prophylaxis

Univentricular hearts, status post Fontan operation

Systemic venous return flows passively to the pulmonary arteries

Decreased LV preload due to slow transit through the pulmonary arteries

Variable single ventricle function, depending on anatomy

Single S1 and S2

Saturations may be as high as low-mid 90s, or may be lower

EKG: variable depending on underlying anatomy

Typically ventricular hypertrophy is seen

TTE: variable depending on anatomy. Severe right atrial dilation if patient had an atriopulmonary Fontan

III

Risk of heart failure

Right of thromboembolic complications

Right of atrial arrhythmias

Monitor for arrhythmias

Avoid volume loading

SBE prophylaxis

Bubble/particle filters on IVs

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Jul 17, 2021 | Posted by in OBSTETRICS | Comments Off on Congenital Heart Disease in Pregnancy

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