Functional dominance of the right coronary artery: Incidence in the human heart

Abstract

After injection of radiopaque medium, 200 human hearts were studied by direct observation and x-ray analysis. The right coronary artery (RC) was dominant in 178 of these hearts as characterized by giving off the typical posterior interventricular artery (PIV), the posterior descending artery. Within this group, 19 specimens had right coronary arteries that gave off both a large posterior interventricular artery (LPIV) and a branch that continued beyond the crux termed a large extension of the right coronary (LERC). The subgroup of hearts supplied thusly was termed real right dominant (RRD). The RC in these hearts supplied the right ventricle and almost half of the left ventricle. These findings explain why proximal lesions of the RC in RRD hearts can be associated with extensive posterolateral ischemia and mitral dysfunction and should be of practical importance when considering angioplasty or by-pass surgery. The diameters and lengths of the arteries of the RC in RRD hearts were measured and compared with the same parameters in typical right dominant hearts.