Anatomic study of the morphology of the right and left coronary arteries

Arising from the aorta, the right (RCA) and left (LCA) coronary arteries provide the arterial supply to both the atria and the ventricles of the heart. An extensive literature review revealed that most studies have either evaluated the morphology of the RCA or the LCA independently. This study aimed to document the relationship between the morphology of the RCA and LCA using coronary angiograms. In addition, variations such as split or double RCA and an absent LCA were documented. A review of 500 coronary angiograms was conducted and the RCA and LCA were classified according to their branching patterns and arterial dominance. The most prevalent branching pattern of the LCA was bifurcation (in 65.8%; 329/500), while trifurcation and quadrifurcation occurred in 20.4% (102/500) and 1.6% (8/500), respectively. The LCA was absent in 11.8% (59/500) of cases with the bifurcation and trifurcation of its branches in 10.8% (54/500) and 1.4% (7/500), respectively. The splitting of the RCA occurred in 4.2% (21/500) of the angiograms. A split RCA with concomitant absent LCA was documented in 1.2% (6/500) of the angiograms. The RCA and LCA were dominant in 77.2% (386/500) and 9.8% (49/500) of cases, respectively, whereas co-dominance occurred in 13% (65/500) of the sample examined. In most cases where a split RCA was present, the RCA was found to be non-dominant. With the advent of coronary arteriography, a comprehensive understanding of coronary arterial anatomy and their anomalies has become essential.