Variations in the Anterior and Posterior Interventricular Coronary Arteries: A Cadaveric Case Report and Review of the Literature

Coronary artery variations can increase the risk of cardiac ischemic events and predispose patients to life-threatening complications during their management. During cadaveric thoracic dissection, the posterior interventricular (PIV) artery was identified as a branch of the right coronary artery (RCA), and it occupied the proximal part of the PIV groove, supplying both ventricles. The RCA then continued further for 35 mm within the left atrioventricular groove. It then descended on the left ventricle parallel to the PIV artery, reaching the apex and supplying both ventricles distally. This is a rare finding, found in 3% of the population. On the anterior aspect of the heart, a 30 mm myocardial bridge was found in the mid-segment of the left anterior interventricular artery (LAIV). The artery continued distally for 44 mm in the anterior IV groove before terminating just before the apex (classifying it as unusually long myocardial bridging (>25 mm)), occurring in just 6% of the population. Literature shows that the most commonly seen myocardial bridging would be <25 mm. At present, there are no reported cases documenting both variations together. Recognising multiple variations coexisting is essential before surgical or percutaneous procedures to prevent significant clinical complications. Long myocardial bridging may cause ischaemic distress due to coronary artery compression, increasing the risk of myocardial ischemia, infarction, conduction abnormalities, and sudden death.