Abstract 14310: Elephant Sitting on My Chest: A Tale of Two Vessels

Abstract

Introduction: A dilated main pulmonary artery (MPA) seen in congenital heart disease (CHD) or pulmonary arterial hypertension (PAH) is a rare cause of angina due to left main coronary artery (LMCA) compression. Case: A 49 year old male with no prior cardiac history presented with substernal chest pain. He reported exercise intolerance for several years. On exam he had an oxygen saturation of 85%, loud P2, fixed split second heart sound and ejection click. Electrocardiogram showed right ventricular (RV) hypertrophy and no significant ST changes. Laboratory data revealed a negative troponin. An enlarged main and right pulmonary artery (RPA) (Figure 1A) was seen on computed tomography (CT) chest angiography for pulmonary embolism (CTPE) and on echocardiography he had a severely dilated RV with decreased function (Figure 1B,1C). Cardiac catheterization showed a step up in saturations from 56 to 71%, Qp:Qs of 1.5 mean MPA pressure of 53 mmHg, pulmonary capillary wedge pressure of 11mmHg and pulmonary vascular resistance (PVR) of 7WU. A slit-like narrowing of LMCA ostium was seen on coronary angiography and intravascular ultrasound (Figure 1D). He was diagnosed with a sinus venosus defect, anomalous right upper pulmonary venous drainage and suspicion for extrinsic compression of LMCA by the dilated RPA that was confirmed on cardiac CT (Figure 1E-I). He was started on triple therapy for PAH with a significant reduction in PA pressures (mean 36 mmHg and PVR 2.1 WU). Percutaneous stenting of the LMCA was deferred and he underwent successful sinus venosus defect repair with a 5mm fenestrated patch, baffling of the anomalous pulmonary veins and a 32 mm interposition graft in the MPA with reduction plasty of MPA/RPA. Conclusion: This is an unusual presentation of unrepaired CHD with angina due to a compressed LMCA from a dilated pulmonary artery. Treatment of the underlying PAH as well as repair of the defect including reduction plasty of the MPA is a consideration for symptomatic relief.