Eisenmenger syndrome — recognition, contraindication to closure and pregnancy counselling

Diagnosis: Eisenmenger syndrome complicating a large unrepaired VSD. The phenotype is the classic triad of central cyanosis, digital clubbing and secondary erythrocytosis (haemoglobin 19.5 g/dL, haematocrit 58%) in a patient with a known congenital shunt never repaired. The large central pulmonary arteries with pruned peripheral vasculature on CXR, the loud P2 (pulmonary hypertension), the RV heave (RV hypertrophy from systemic-level PA pressure), and the early-diastolic left-parasternal murmur (Graham-Steell murmur of functional pulmonary regurgitation from a dilated pulmonary artery) together establish severe pulmonary arterial hypertension at systemic level with shunt reversal. Echo confirms bidirectional shunt and systemic PA pressures.^[1][2]

Pathophysiology. An unrepaired VSD drove chronic left-to-right shunting with pulmonary over-circulation; the pulmonary arterioles remodelled (medial hypertrophy, intimal proliferation, plexiform lesions) until PVR rose to and then exceeded systemic vascular resistance, reversing the shunt to right-to-left. Deoxygenated venous blood enters the systemic circulation, producing central cyanosis; chronic tissue hypoxaemia stimulates renal erythropoietin, producing secondary erythrocytosis (distinguished from polycythaemia vera by normal white cell count, platelets, and JAK2-negative status).^[1]

Critical management principle: do NOT close the defect. Closure at this PVR level removes the 'pop-off' that allows the right ventricle to decompress through the shunt, abruptly raises RV afterload and precipitates fatal right-heart failure. ESC 2020: complete ASD/shunt closure is avoided when PVR is 5 Wood units or more; vasoreactivity testing is not recommended to decide ASD closure at that PVR.^[1]

Targeted PAH therapy (cornerstone of treatment). Initiate bosentan (dual endothelin-receptor antagonist) — BREATHE-5 (Galiè, Circulation 2006): 54 WHO functional class III patients, 16 weeks, bosentan 37 vs placebo 17; placebo-corrected 6-minute-walk +53.1 m, PVRi −472.0 dyne·s·cm⁻⁵, mPAP −5.5 mmHg, pulse oximetry +1.0% (did not worsen saturation). Liver-function monitoring and pregnancy avoidance follow specialist protocols; bosentan is teratogenic.^[6]

Supportive measures. ESC 2020: routine phlebotomy should be avoided; treat iron deficiency; pregnancy in Eisenmenger is contraindicated; oestrogen-containing contraception is among the exposures to avoid; use an air filter on intravenous lines. Vongpatanasin: excessive phlebotomy causes microcytosis and exacerbates hyperviscosity symptoms.^[1][10]

Endocarditis prophylaxis before at-risk dental procedures — ESC 2020 high-risk conditions include any cyanotic CHD, prosthetic valves (including transcatheter), previous IE, and CHD repaired with prosthetic material for 6 months (lifelong if residual shunt or regurgitation).^[1]

Pregnancy counselling — this is the central counselling task. Eisenmenger syndrome is mWHO IV — pregnancy should definitely be avoided (ESC 2020 cardiac event rate 40–100% in class IV). Contemporary pooled maternal mortality in pulmonary-hypertension pregnancy is 7.6% (4583 patients), with 93% of deaths postpartum; Eisenmenger is associated with higher mortality. Offer termination if already pregnant and highly effective oestrogen-free contraception.^[1][14]

Contraception — levonorgestrel intrauterine system (Mirena) or copper IUD is first-line (highly effective, oestrogen-free, safe in pulmonary hypertension). Progestogen-only pill is acceptable but less effective. Combined oral contraceptives are contraindicated (thrombosis risk in PAH). The patient should be referred to a dedicated ACHD contraception service.^[4]

Disposition. Lifelong follow-up at a specialist ACHD centre (great complexity, physiological stage D). Annual review with ECG, echo, bloods; biennial cardiac MRI; CPET for prognostic stratification. Consider heart-lung (or lung with intracardiac repair) transplantation referral for end-stage disease failing targeted therapy, at a specialist ACHD centre.^[10]