MORPHOLOGICAL STUDY OF CORONARY OSTIA

Objective: To study the normal and variant anatomy of the coronary artery ostia in south Indian population. Introduction: Sudden cardiac deaths, especially in young are on the rise in recent days. Of all causes for sudden cardiac death, anomalous origins of coronary arteries also comprise a significant percentage. A cadaveric study of the origin of coronary arteries in an unsuspected population in south India paves way for understanding the normal variants & to determine the prevalence of anomalies and the need for screening for such anomalies. Methods: Fifty adult heart specimens of unknown age and sex were dissected. The number of ostia and their positions within the respective sinuses were observed. Vertical and circumferential deviations of the ostia were observed. Results: Of all hearts,the coronary arteries arose from the aortic sinuses in 99 hearts; no openings were present in the pulmonary artery or the non-coronary sinus. In one heart, the left coronary artery was absent, wherein the anterior inter ventricular artery and the left circumflex artery had independent origins from the aortic sinuses.The number of openings in the aortic sinuses varied from 2-3 in the present study; multiple ostia were seen in the right posterior sinus. The majority of the ostia lay below the sinutubular ridge (89% for RCA & 92% for LCA) and at or above the level of the upper margin of the cusps (84%). Left ostial openings were mainly centrally located (80%), whereas the right coronary ostia were often shifted towards the right posterior aortic sinus (59%). Discussion: The usual location of the ostia was within the sinus and above the cusps, but below the sinutubular ridge. On occasion, normal variants like multiple ostia, vertical or circumferential shift in the position, and slit-like ostia may create confusion in interpreting the images and pose a difficulty during procedures like angiography, angioplasty, and coronary artery bypass surgery.