Makindo Medical Notes

🔄 Eisenmenger’s syndrome is a late complication of an uncorrected congenital heart lesion with an initial left-to-right shunt that progresses to pulmonary hypertension and reversal to a right-to-left shunt. This causes central cyanosis and multisystem complications.

📖 About

• Increased pulmonary blood flow → pulmonary hypertension.
• As pulmonary pressures rise, shunt reverses (right → left) 🫀.
• Most often follows an uncorrected VSD.
• Preventable with early surgical correction ✅.
• Pregnancy is contraindicated 🚫 (maternal mortality >30%).

🧬 Aetiology / Pathophysiology

• Lungs = low-resistance vascular network, normally supplied by the low-pressure RV.
• Large L→R shunt (VSD, PDA, ASD) → excessive pulmonary flow → irreversible pulmonary vascular disease.
• Eventually, pressures equalise → deoxygenated blood shunts to systemic circulation → cyanosis 💙.
• Endocarditis prophylaxis is recommended.

🔎 Causes (Shunts leading to Eisenmenger’s)

• Ventricular septal defect (VSD) – murmur disappears, replaced by pulmonary regurgitant murmur.
• Atrioventricular septal defect (AV canal defect).
• Atrial septal defect (ASD).
• Patent ductus arteriosus (PDA).
• Persistent truncus arteriosus.
• Transposition of the great arteries (with shunt).

🩺 Clinical Features

• 💉 Polycythaemia → hyperviscosity, gout (urate overproduction).
• Cyanosis + finger clubbing.
• VSD murmur disappears as shunt reverses.
• Cerebral embolic phenomena (paradoxical emboli).
• Gallstones (chronic haemolysis), cholelithiasis.
• Loud P2 due to pulmonary hypertension.
• Endocarditis risk ↑.

📊 Investigations

• Bloods: FBC – polycythaemia, ↑ urate.
• CXR: enlarged pulmonary arteries, peripheral pruning, right heart enlargement.
• ECG: right ventricular hypertrophy, right atrial enlargement, AF possible.
• Echo: high right-sided pressures, shunt reversal.
• Cardiac catheterisation: confirms pulmonary hypertension + shunt direction.

💊 Management

• Supportive: Oxygen (limited effect but helpful acutely), cautious phlebotomy for hyperviscosity, aspirin, allopurinol for gout.
• Medications: Pulmonary vasodilators (e.g., bosentan, sildenafil), anticoagulants, diuretics for right heart failure.
• Definitive: Once Eisenmenger develops, shunt repair is too late ⏱️.
• Transplant: Combined heart–lung transplantation = only curative option.

🚨 Key teaching pearl: In Eisenmenger’s, the disappearance of a previously loud VSD murmur should raise alarm — it means the shunt has reversed!

Cases — Eisenmenger’s Syndrome

• Case 1 — Long-Standing VSD: A 28-year-old man with an unrepaired ventricular septal defect presents with progressive breathlessness, cyanosis, and clubbing. O₂ sats 82% on room air. Exam: loud P2, right ventricular heave. Echo: large VSD with right-to-left shunting, severe pulmonary hypertension. Diagnosis: Eisenmenger’s syndrome due to chronic VSD. Management: Supportive (oxygen, pulmonary vasodilators like sildenafil, anticoagulation if indicated); avoid pregnancy; heart–lung transplantation in severe cases.
• Case 2 — Atrial Septal Defect (ASD): A 35-year-old woman with childhood-diagnosed secundum ASD presents with exertional dyspnoea, fatigue, and cyanosis. Exam: fixed split S2, pulmonary ejection systolic murmur, digital clubbing. Echo + right heart cath: severe pulmonary hypertension with reversed shunt. Diagnosis: Eisenmenger’s syndrome secondary to ASD. Management: Cannot close defect at this stage; supportive therapy with endothelin receptor antagonists, pulmonary vasodilators, and referral to adult congenital heart disease unit.
• Case 3 — PDA-Associated Eisenmenger’s: A 25-year-old woman presents with cyanosis, clubbing, and differential cyanosis (blue toes, pink fingers). She has loud P2, continuous murmur absent. Echocardiography: patent ductus arteriosus with right-to-left shunt and severe pulmonary hypertension. Diagnosis: Eisenmenger’s physiology due to PDA. Management: Pulmonary vasodilators (bosentan, sildenafil), avoid pregnancy, specialist referral. Transplantation may be required in end-stage disease.

Teaching Commentary 💙

Eisenmenger’s syndrome is the end-stage complication of a long-standing left-to-right congenital shunt (VSD, ASD, PDA). Chronic pulmonary overcirculation leads to pulmonary vascular remodelling and hypertension, eventually reversing the shunt to right-to-left, causing cyanosis and clubbing. Clinical clues: cyanosis, loud P2, right heart failure, differential cyanosis in PDA. Once Eisenmenger develops, defects are no longer operable. Management is supportive — pulmonary vasodilators, anticoagulation, avoiding pregnancy — and definitive treatment is heart–lung or lung + cardiac surgery transplantation.