PULMONARY HYPERTENSION AS AN INITIAL PRESENTATION OF UNCORRECTED TETRALOGY OF FALLOT IN A 27-YEAR-OLD

Abstract

TOPIC: Pulmonary Vascular Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease (CHD) affecting children. It is characterized by ventricular septal defect (VSD), an overriding aorta, pulmonary stenosis or atresia, and right ventricular hypertrophy. Historically, severity of RV outflow obstruction determined the need for surgical intervention and only 3% of patients with unrepaired TOF reached the age of 40. With advances in early surgical repair and excellent surgical outcomes, survival 25 years after TOF repair has reached more than 94% in the United States and TOF is rarely left unrepaired, however, pulmonary arterial hypertension (PAH) continues to be a major complication in both repaired and unrepaired cases. CASE PRESENTATION: Case: A 27-year-old Vietnamese immigrant presented with complaints of hemoptysis, dyspnea, orthopnea, decreased exercise tolerance, and congestion. In the emergency department he was febrile, normotensive, non-tachycardic, cyanotic and hypoxic with an oxygen saturation of 79%. Investigations were significant for abnormal chest X-rays, leukocytosis to 19 and polycythemia to 20. He was treated for community-acquired pneumonia. Computed tomography angiogram of the chest showed the features of TOF with direct arterial communications to both lungs associated with the descending aorta. Echocardiogram showed an ejection fraction of 55%, an overriding aorta, a dilated aortic root (5cm), severely elevated pulmonary artery systolic pressure, VSD with right to left shunt, and tricuspid regurgitation velocity of 4.3m/s suggesting a Right Ventricle systolic pressure of 85 mmHg. He was diagnosed with unrepaired TOF with pulmonary valve atresia and major aortopulmonary collateral arteries (MAPCAs). Right and left heart catheterization showed a mean pulmonary artery pressure of 68 mmHg and pulmonary artery wedge pressure 14. He was diagnosed with PAH and was started on Bosentan therapy. His symptoms and exercise tolerance significantly improved. His follow-up visit saturation was 84%. DISCUSSION: Patients with TOF usually have systemic-pulmonary shunting. This increased flow leads to increased pressure and progressive endothelial dysfunction which results in arterial remodeling/PAH. Early surgical repair in CHD limits the amount of vascular remodeling and development of PAH. However, up to 15% of patients develop PAH even after surgical repair. There is a high mortality if untreated. CONCLUSIONS: In this case of TOF with MAPCAS and Eisenmenger syndrome, the endothelin receptor antagonist Bosentan was used with success. PAH can be the initial presentation of adult TOF. REFERENCE #1: John Willis Hurst, et al. Hurst's the Heart. 14th ed., vol. 2, New York, McGraw-Hill Medical, 2011, pp. 1380–1381. REFERENCE #2: https://onlinelibrary.wiley.com/doi/pdf/10.1002/clc.4960070807 REFERENCE #3: https://jamanetwork.com/journals/jamacardiology/fullarticle/2718499#:~:text=Tetralogy%20of%20Fallot%20%28TOF%29%20is%20the%20most%20common, or%20variation%20in%20population%20or%20health%20care%20systems. DISCLOSURES: No relevant relationships by Moises Cossio, source=Web Response No relevant relationships by Fernando Fuentes, source=Web Response No relevant relationships by Mohammad Nimer, source=Web Response