Congenital Heart Disease in the Adult¶
Chapter 280 | Part 6: Disorders of the Cardiovascular System
KEY CLINICAL POINTS¶
- Prevalence of congenital heart disease (CHD) in adults is estimated at ≥ 1.4 million in the U.S., with >10% of adults in Europe over 60 years old.
- Adult CHD management requires lifelong care, with specialized ACHD programs and multidisciplinary teams due to complex anatomical and physiological challenges.
- Key lesions include atrial septal defects (ASD), ventricular septal defects (VSD), tetralogy of Fallot (TOF), transposition of great arteries (TGA), and single ventricle physiology.
- Management involves surgical repair, transcatheter interventions, and long-term monitoring for complications like pulmonary hypertension and arrhythmias.
- Pregnancy in women with CHD requires preconception counseling, risk stratification using weighted-risk scores, and avoidance of teratogenic medications.
1. DEFINITION & OVERVIEW¶
Congenital heart disease (CHD) in adults refers to structural cardiac anomalies present at birth that persist into adulthood. These defects may be asymptomatic or lead to progressive complications requiring intervention. Management involves a multidisciplinary approach due to the complexity of anatomical and physiological challenges.
Table 280-1: Modified WHO Classification of Heart Disease in Pregnancy¶
| mWHO I | mWHO II | mWHO II–III | mWHO III | mWHO IV |
|---|---|---|---|---|
| Small or mild pulmonary stenosis | Unoperated atrial or ventricular septal defect | Mild left ventricular impairment (EF >45%) | Pulmonary arterial hypertension | No detectable increased risk of maternal mortality |
| Patent ductus arteriosus | Repaired tetralogy of Fallot | Hypertrophic cardiomyopathy | Severe systemic ventricular dysfunction (EF <30%) | Small increased risk of maternal mortality |
| Mitral valve prolapse | Most arrhythmias (supraventricular) | Native or tissue valve disease not considered WHO I or IV | Previous peripartum cardiomyopathy with residual impairment | Intermediate increased risk of maternal mortality |
| mWHO I | mWHO II | mWHO II–III | mWHO III | mWHO IV |
|---|---|---|---|---|
| Successfully repaired simple lesions (atrial/ventricular septal defect, patent ductus arteriosus) | Turner syndrome without aortic dilatation | Marfan or other HTAD syndrome without aortic dilatation | Mechanical valve, systemic right ventricle with good function | Moderate to severe increase in morbidity |
| Atrial or ventricular ectopic beats, isolated dilatation | Aorta <45 mm in bicuspid aortic valve pathology | Repaired coarctation, atrioventricular septal defect | Fontan circulation with complications | Extremely high risk of maternal mortality |
1.1 Congenital Terminology, Development, and Genetics¶
CHD is the most common birth defect, with etiologic factors including chromosomal abnormalities (e.g., 22q11 deletion in DiGeorge syndrome), genetic syndromes (e.g., Noonan syndrome), and environmental influences. Cardiac development involves mesodermal cell migration, neural crest cell contributions, and septation processes. Genetic counseling is critical for families with heritable conditions like Marfan syndrome or Williams syndrome.
1.2 Changing Landscape of Adult CHD¶
Adult CHD has become a distinct subspecialty with standardized care guidelines. ACHD programs emphasize lifelong follow-up, with certifications and advanced training for managing complex cases. National initiatives have improved outcomes through coordinated care involving cardiologists, surgeons, and other specialists.
2. EPIDEMIOLOGY¶
CHD affects ~1.4 million adults in the U.S. and is projected to grow to >10% of adults in Europe over 60 years old by 2030. Most adults with CHD were diagnosed in childhood, but ~20% are diagnosed as adults. Lifelong follow-up with ACHD specialists is recommended due to the risk of progressive complications and comorbidities.
Table 280-2: Congenital Etiologies of Right Heart Dilation¶
| Etiologies | |
|---|---|
| Congenital tricuspid valve disease (e.g., Ebstein anomaly, tricuspid regurgitation) | |
| Congenital pulmonary valve regurgitation | |
| Pulmonary arterial hypertension | |
| Myocardial abnormalities (e.g., arrhythmogenic RV cardiomyopathy, Uhl’s anomaly) | |
| Shunt lesions (e.g., partial anomalous pulmonary venous return, primum ASD, secundum ASD) | |
| Coronary artery fistula to RA/CS | Postoperative residual shunts |
2.1 Risk Factors and Demographics¶
Risk factors include genetic syndromes (e.g., Down syndrome, Noonan syndrome), chromosomal abnormalities (e.g., 22q11 deletion), and environmental exposures. Adults with CHD are at higher risk for complications like arrhythmias, heart failure, and pulmonary hypertension. Women with CHD require special prenatal and perinatal management.
3. ETIOLOGY & PATHOPHYSIOLOGY¶
CHD arises from developmental anomalies during cardiac morphogenesis. Key mechanisms include abnormal septation, valve malformations, and shunt formation. Genetic factors (e.g., 22q11 deletion, Noonan syndrome) and environmental influences (e.g., maternal diabetes, exposure to teratogens) contribute to pathogenesis. Long-term complications include ventricular remodeling, pulmonary hypertension, and arrhythmias.
3.1 Cardiac Development¶
The heart forms in the third week of gestation, with mesodermal cells forming the primary heart tube. Septation and valve development depend on cardiac neural crest cells and second heart field proliferation. Congenital defects arise from disruptions in these processes, such as conotruncal malformations or septal defects.
4. CLINICAL FEATURES¶
Clinical manifestations vary by lesion type. Common features include dyspnea, fatigue, chest pain, and syncope. Right heart dilation may present with signs of tricuspid regurgitation (e.g., fixed S2 split, prominent v-waves). Left heart dilation is associated with pulmonary hypertension and systemic symptoms. Adults with unrepaired ASD may develop Eisenmenger syndrome with cyanosis.
4.1 Specific CHD Lesions¶
Key lesions include atrial septal defects (ASD), ventricular septal defects (VSD), patent ductus arteriosus (PDA), tetralogy of Fallot (TOF), transposition of great arteries (TGA), and single ventricle physiology. Each has distinct hemodynamic effects and clinical presentations.
5. DIFFERENTIAL DIAGNOSIS¶
Differential diagnoses for right/left heart dilation include valvular heart disease, cardiomyopathies, and acquired conditions like pulmonary hypertension. For cyanosis, differential includes congenital heart defects, lung disease, and hemoglobinopathies. ACHD specialists use imaging and hemodynamic data to distinguish congenital vs acquired causes.
6. INVESTIGATIONS & DIAGNOSIS¶
Diagnosis involves echocardiography (transthoracic, transesophageal), cardiac MRI, and angiography. Electrocardiography identifies arrhythmias and conduction abnormalities. The weighted-risk score for pregnancy includes factors like prior cardiac events, mechanical valves, and functional status. Diagnostic criteria for Eisenmenger syndrome include pulmonary hypertension and cyanosis.
7. MANAGEMENT & TREATMENT¶
Management includes surgical repair (e.g., ASD closure, VSD patch), transcatheter interventions (e.g., TAVI, edge-to-edge clip repair), and medical therapy for complications. Long-term monitoring for arrhythmias, heart failure, and pulmonary hypertension is essential. Pregnancy requires multidisciplinary care with avoidance of teratogenic medications.
Table 280-3: Potential Sequelae of Repaired Tetralogy of Fallot¶
| Sequelae | |||
|---|---|---|---|
| Right atrial dilation | Right ventricular dilation | Right ventricular dysfunction | Right ventricular outflow tract obstruction |
| Pulmonary regurgitation | Branch pulmonary artery stenosis | Tricuspid regurgitation | Residual ventricular septal defect |
| Left ventricular dysfunction | Aortic root dilation | Atrial arrhythmias | Ventricular arrhythmias |
| Sudden cardiac death |
7.1 Surgical Interventions¶
Surgical options include tricuspid valve repair, double valve replacement, and Fontan procedures. Percutaneous interventions like PDA closure and ASD occlusion are preferred for high-risk patients. Reintervention may be needed for progressive disease or complications like pulmonary regurgitation.
8. PROGNOSIS & COMPLICATIONS¶
Prognosis varies by lesion type and treatment. Adults with repaired TOF have 72% survival at 40 years but only 25% event-free survival due to reinterventions (e.g., pulmonary valve replacement). Complications include arrhythmias, heart failure, and pulmonary hypertension. Long-term survivors of Fontan procedures face risks of thromboembolism, liver dysfunction, and arrhythmias.
9. SPECIAL CONSIDERATIONS¶
Pregnancy in women with CHD requires preconception counseling, risk stratification using weighted-risk scores, and avoidance of ACE inhibitors/ARBs. Adults with CHD may have limited hemodynamic reserve and require careful management of anticoagulation. Transition from pediatric to adult care is complex due to disparities in healthcare access and social determinants.
10. KEY POINTS & CLINICAL PEARLS¶
- Lifelong follow-up with ACHD specialists is critical for optimal outcomes.
- Pregnancy in women with CHD requires multidisciplinary care and avoidance of teratogenic medications.
- Transcatheter interventions (e.g., TAVI, ASD closure) are preferred for high-risk patients.
- Long-term survivors of Fontan procedures face unique risks of thromboembolism and liver dysfunction.
- Genetic counseling is essential for families with heritable conditions like Noonan syndrome or Williams syndrome.