Variant anatomy of coronary arteries

Abstract

Introduction: Wide variations exist in the size, position, and shape of various body organs, finger prints, and proteins in different individuals. Some variations are of considerable clinical importance, such as the coronary arteries. Variations of coronary arteries can cause important clinical manifestation, including sudden death of the individual. Materials and Methods: Coronary arteries were dissected in 10% formalin-fixed cadaveric hearts. The normal and variant anatomy of coronary arteries was studied. Result: In 100% of cases, the right coronary artery (RCA) and main left coronary artery (LCA) were found to arise from anterior aortic sinus and left posterior aortic sinus, respectively. In 8% of cases, the conus was found to have independent origin from the anterior aortic sinus. The RCA was found to be dominant in 90% of cases. In 66.7% of cases, the length of RCA ranged from 4.5 cm to 7 cm. The average length of LCA was found to be 7 mm. In 10% of cases, the circumflex coronary artery was found to be dominant, where the length of the artery ranged 9-11 cm. In 10% of cases, LCA trifurcated, where the obtuse marginal branch was replaced by the ramus intermedius branch. Also, 43.3% of LAD showed myocardial bridging predominantly in the middle 1/3 rd segment, and 6.7% of cases of RCA showed myocardial looping. Discussion: Coronary arteries show immense variation in their origin, termination, branching pattern, myocardial bridging, looping, and dominance pattern. This knowledge is clinically and surgically important to manage coronary artery diseases.