P1727 Large coronary artery to pulmonary artery fistula as primary source of pulmonary blood supply in tetralogy of fallot with pulmonary atresia

Abstract

Abstract Funding Acknowledgements Not Applicable OnBehalf Not Applicable Introduction Pulmonary blood supply in patients of Tetralogy of Fallot with pulmonary atresia is usually from patent arterial duct or major aortopulmonary collaterals (MAPCAs) arising from descending thoracic aorta. We describe a case in which large coronary to pulmonary artery fistula was the primary source of pulmonary blood supply. Case Report A 17 years old female was referred to our hospital for diagnostic workup of suspected congenital heart disease. She was previously undiagnosed and now complains of progressive shortness of breath for last few months. On physical examination she was non-dysmorphic with oxygen saturation of ∼ 77 % in room air, blood pressure of ∼ 117/72 mmHg, pulse rate of ∼ 89 beats per minute and respiratory rate of ∼ 24 breaths per minute. She was clinically cyanosed with grade 3 clubbing and polycythemic. Cardiovascular examination revealed quiet precordium with normally placed apex beat, grade 2 parasternal heave with single second heart sound and grade 3/6 continuous murmur along left mid sternal border. Twelve lead electrocardiogram (ECG) showed normal sinus rhythm, right axis deviation and right ventricular hypertrophy. There was no evidence of ischemia. Chest X-ray revealed "boat shaped heart" with oligaemic lung fields. Transthoracic echocardiography showed large conoventricular ventricular septal defect with bidirectional flow. There was aortic over-ride with dilated left main coronary artery. No forward flow was seen across right ventricular outflow tract. Considering hugely dilated left main coronary artery, suspicion of coronary to pulmonary artery fistula was made and cardiac computed tomography followed by conventional angiography was done, both confirmed the diagnosis of Tetralogy of Fallot with pulmonary atresia and large coronary artery to main pulmonary artery fistula as a primary pulmonary blood supply. Two small collaterals (MAPCAs) were also identified supplying small part of right and left lungs. Conclusion This case highlights unusual source of pulmonary blood supply in Tetralogy of Fallot with pulmonary atresia. Correct pre-operative diagnosis is essential for appropriate surgical planning and better outcome. Abstract P1727 Figure. TOF-PA with CA to PA Fistula