A Left Atrial Myxoma Masquerading As Acute Coronary Syndrome

Acute coronary syndrome is caused by a rupture of atherosclerotic plaque with superimposed thrombus formation. Non-ST-segment elevation acute coronary syndrome (NSTE-ACS) occurs when occlusion of the epicardial coronary artery by a thrombus causes partial thickness myocardial ischemia and an ischemic cascade downstream. Cardiac masses are known to produce symptoms predominantly by local obstruction or systemic embolism. Coronary artery tumor embolism causing acute coronary syndrome is a rare presentation of cardiac mass. We report NSTE-ACS as the initial presentation of the left atrial myxoma in a 62-year-old woman. She presented to the emergency department with acute onset severe anginal chest pain, diaphoresis, and dizziness. Her serial electrocardiograms (ECGs) were normal, and serial troponins were elevated, consistent with non-ST-segment elevation acute coronary syndrome. Cardiac catheterization revealed insignificant coronary artery disease, and transthoracic and transesophageal echocardiograms showed a left atrial mass attached to the interatrial septum consistent with myxoma. The patient underwent surgical excision, and histopathology was consistent with myxoma. Her symptoms subsided after surgery. Primary cardiac tumors are very uncommon and can present with myriad symptoms, from tumor embolism, local cardiac effects, to constitutional symptoms. Although embolism to other organs has been reported, left atrial myxoma presenting as an acute coronary syndrome is very uncommon.