Anomalous left main coronary artery originating from the pulmonary artery

Abstract

An 81 year-old Caucasian female presented to the hospital with dyspnea on exertion and was found to be in new onset atrial fibrillation. She has a past medical history of hypertension and has led an active life till her symptoms of dyspnea started. An echocardiogram was performed as a part of the work up showing an ejection fraction of 35 % with moderate mitral valve regurgitation (Fig. 2). Given her new onset cardiomyopathy and reluctance to undergo invasive work up, a pharmacologic nuclear myocardial perfusion stress test was performed showing a moderate sized area of anterolateral wall mixed ischemia and scar with an ejection fraction of 36 % (Fig. 3). A coronary angiography was recommended but patient was still reluctant and preferred a non-invasive work-up. Thus, a cardiac CT angiography was recommended. This showed an anomalous left main coronary artery originating from the proximal main pulmonary artery just beyond the pulmonic valve. The contrast density in the left main coronary artery is slightly higher than in the pulmonary artery and matches the contrast density in the arterial circulation indicating collateral filling of the left coronary system from either the aorta or right coronary artery (Fig. 4). She was started on beta-blockers and lisinopril. She underwent a successful electrical cardioversion preceded by a transesophageal echocardiogram to rule out left atrial appendage clot. She was started and warfarin and discharged. On follow-up 3 months later, she remained in sinus rhythm with significant improvement in her symptoms. A repeated echocardiogram showed significant improvement in the left ventricular ejection fraction to 55 % with only mild mitral regurgitation. On six-month follow-up she remained asymptomatic with improved functional capacity.