Unrepaired Tetralogy of Fallot with Pulmonary Atresia and Major Aorto-pulmonary Collateral Arteries in Pregnancy: A Case Report

Tetralogy of Fallot with pulmonary atresia and major aortopulmonary collateral arteries (MAPCA) represents the most severe variant of this congenital heart disease, with complete atresia of the pulmonary valve replacing pulmonary stenosis. Pregnancy in women with unrepaired lesions of this complexity is exceedingly rare and associated with major maternal and fetal risks. The authors report the case of an 18-year-old primigravida presenting at 31 weeks’ gestation with progressive dyspnoea, cyanosis, and peripheral oedema. Clinical evaluation and echocardiography revealed unrepaired tetralogy of Fallot with pulmonary atresia, a large ventricular septal defect, and MAPCAs. She was managed with diuretics, nitrates, antiplatelet therapy, and prophylactic heparin. Cardiac CT confirmed the diagnosis, demonstrating absent native pulmonary arteries and a MAPCA arising from the aortic root. Despite medical stabilisation and multidisciplinary care, she required Caesarean delivery at 35 weeks for fetal distress. A live but premature infant weighing 1.1 kg was delivered; however, neonatal demise occurred on Day 3. The mother remained stable post-partum and was discharged on medical management, though she declined surgical intervention. This case highlights the profound challenges of managing pregnancy in unrepaired tetralogy of Fallot with pulmonary atresia and MAPCAs, particularly in resource-limited settings. It underscores the need for early pre-pregnancy counselling, risk stratification, and coordinated multidisciplinary care in specialised centres to improve outcomes for both mother and child.