Anomalous Left Circumflex Artery With ST Depressions and T-wave Inversions in a Healthy Athlete: A Case Report

An anomalous left circumflex artery is a congenital anatomic variant of typical coronary circulation that can potentially contribute to cardiac ischemia or altered blood flow. These variants can cause changes to be seen on electrocardiograms, particularly to the T wave and ST segments, including depressions, inversions, or elevations. We describe the case of a healthy 35-year-old man with previously undiagnosed anomalous origin of the left circumflex artery from the right coronary artery ostium with evidence of ST-segment changes and T-wave inversions on electrocardiogram during exercise stress testing, despite the lack of evidence of atherosclerosis and the patient being in good cardiac health otherwise. Anomalous left circumflex arteries can present with altered hemodynamics in some patients, particularly during strenuous exercise, as this arterial change disrupts the typical cardiac blood flow. Repeat stress testing done with a treadmill myocardial perfusion study prior to the patient's participation in a marathon showed no persistence of the ST changes. Given the reassuring findings of the lack of ST changes and the patient having no symptoms of ischemia, such as chest pain or shortness of breath, the patient was advised to continue his current activity level while diligently monitoring for symptoms of myocardial ischemia. This case shows that even though this anomaly can be asymptomatic, ST changes can potentially occur due to altered hemodynamics in the coronary circulation that could require additional monitoring.