Congenital Heart Disease in Adults

CHD in Adults - Not Just Kids

Adult Congenital Heart Disease (ACHD): Defects from birth, persisting/presenting in adulthood; prevalence ↑.

• Adult Presentation: Often insidious. Key differences from childhood:
  • Arrhythmias (most common).
  • Paradoxical embolism (stroke/TIA).
  • Pulmonary Hypertension (PHTN), Eisenmenger risk.
  • Heart Failure.
• Essential Diagnostics:
  • Echo (TTE/TEE): First-line.
  • Cardiac MRI (CMR): RV, shunts.
  • CT Angiography: Anatomy.
  • Cardiac Catheterization: Pressures, intervention.
• Broad Classification:
  • Acyanotic: L→R shunts (ASD, VSD), Obstructive (AS, PS).
  • Cyanotic: R→L shunts (TOF, TGA), Complex.

⭐ Atrial Septal Defect (ASD) is the most common congenital heart defect to present for the first time in adulthood.

Acyanotic Shunts (L→R) - Overload Story

L→R shunts cause pulmonary overcirculation & chamber overload.

• Atrial Septal Defect (ASD)
  • Ostium secundum commonest. L→R shunt → RA/RV volume overload.
  • Clinical: Fixed wide split S2.
  • Complications: Atrial fibrillation, PHTN, paradoxical emboli.
  • Closure: If $Q_p:Q_s > \mathbf{1.5:1}$ or RV overload.
• Ventricular Septal Defect (VSD)
  • Adults: Often restrictive; loud pansystolic murmur.
  • Complications: Infective endocarditis (IE), aortic regurgitation, PHTN (if large).
  • Closure: Symptomatic, significant shunt ($Q_p:Q_s > \mathbf{1.5:1}$), LV overload.
• Patent Ductus Arteriosus (PDA)
  • Aorta → PA shunt.
  • Clinical: Continuous 'machinery' murmur.
  • Complications: PHTN, endarteritis, HF.
  • Closure: Generally recommended in adults.

⭐ A continuous 'machinery' murmur at the left infraclavicular area is characteristic of Patent Ductus Arteriosus (PDA).

Cyanotic & Eisenmenger - Blue Reality

• Tetralogy of Fallot (TOF) - Adult Post-Repair:
  • Chronic severe pulmonary regurgitation (PR) → RV dilatation/dysfunction.
  • Arrhythmias (e.g., VT); QRS duration >180ms is a key risk factor.
  • Pulmonary valve replacement (PVR) indicated for symptomatic PR or progressive RV compromise.
• Transposition of Great Arteries (TGA) - Adult:
  • Post-Atrial Switch (Mustard/Senning): Baffle obstruction/leaks, arrhythmias, systemic (RV) failure.
  • Post-Arterial Switch (Jatene): Pulmonary artery (PA) stenosis, neoaortic root dilatation.
• Eisenmenger Syndrome: Irreversible pulmonary hypertension (PHTN) with reversed (R→L) shunt.
  • Clinical Triad: PHTN, cyanosis, erythrocytosis.
  • Management: Supportive care, advanced PHTN therapies, strict contraception. ⚠️ Defect closure is contraindicated.
• Chronic Cyanosis Complications:
  • Erythrocytosis (target Hct <65%), hyperviscosity syndrome, coagulopathy (bleeding/thrombosis), gout, brain abscess.

⭐ In repaired Tetralogy of Fallot, significant chronic pulmonary regurgitation leading to RV dysfunction is a major long-term concern, often necessitating pulmonary valve replacement (PVR).

Obstructive Lesions - Pressure Game

• Coarctation of Aorta (CoA):
  • Upper limb HTN, radio-femoral delay, rib notching.
  • Assoc: Bicuspid aortic valve, Turner's.
  • Complications: Cerebral aneurysms, dissection.
  • Intervention: Gradient > 20 mmHg.
• Congenital Aortic Stenosis (AS):
  • Often bicuspid. Exertional symptoms (dyspnea, angina, syncope), ESM.
  • Intervention: Symptomatic severe; Asymptomatic severe + (LV EF < 50% / abnormal stress test).
• Congenital Pulmonary Stenosis (PS):
  • Valvular common. Severity by echo gradient.
  • Intervention (valvuloplasty): Symptomatic; Asymptomatic severe (gradient > 40 mmHg, RV dysfunction).
• Ebstein's Anomaly:
  • Apical tricuspid displacement → atrialized RV, TR.
  • WPW common, cyanosis (R-L shunt).
  • 📌 Ebstein's: Eccentric WPW, Enlarged RA.

⭐ Bicuspid aortic valve: most common congenital heart defect; assoc. CoA, AS.

High‑Yield Points - ⚡ Biggest Takeaways

• Atrial Septal Defect (ASD): Most common adult CHD; presents with fixed wide S2 split.
• Eisenmenger Syndrome: Irreversible pulmonary hypertension with shunt reversal (R→L), causing late cyanosis and clubbing.
• Ventricular Septal Defect (VSD): Holosystolic murmur at left lower sternal border; smaller defects are often louder.
• Patent Ductus Arteriosus (PDA): Continuous machinery murmur; risk of infective endarteritis and pulmonary hypertension.
• Coarctation of Aorta: Upper limb hypertension, diminished femoral pulses (radio-femoral delay), and rib notching on CXR.
• Tetralogy of Fallot (TOF): Most common cyanotic CHD surviving to adulthood, usually post-repair; look for RV dysfunction or arrhythmias.