Coronary arteries, myocardial bridges, and coronary dominance: A cadaveric study

Coronary dominance describes the anatomical pattern of myocardial perfusion, whereas myocardial bridging refers to an intramyocardial course of the coronary arteries branches. Because both findings may be associated with clinically relevant conditions, they are often regarded as occupying an intermediate spectrum between anatomical variation and anomaly. In this study, we assessed the prevalence and morphometric characteristics of myocardial bridges and coronary dominance in 201 adult human hearts by means of cadaveric dissection in a brazilian institution. Additionally, the main arteries were measured, and the relationship between myocardial bridging and coronary dominance was examined. The mean length of the right coronary artery was 115.71±35.54mm, followed by 12.26±5.12mm for the left coronary artery, 110.33±22.47mm for the anterior interventricular artery, and 57.39±17.78mm for the posterior interventricular artery. Myocardial bridges were identified in 56.2% of specimens, predominantly in the anterior interventricular artery (81.3%), followed by the posterior interventricular artery (11.6%) and other branches (7.1%). The mean bridge length was 15.97±9.56mm. A single myocardial bridge was observed in 40.8% of hearts, whereas 15.4% of them presented multiple bridges. Regarding coronary dominance, 66.2% of hearts were right-dominant, 23.4% were balanced, and 10.4% were left-dominant. Among hearts with myocardial bridges, 67.3% were right-dominant, 23.0% were balanced, and 9.7% were left-dominant. Overall, coronary dominance patterns and arterial morphometry were consistent with previous reports; however, the prevalence of myocardial bridging was higher than the described in the literature. Given the potential association of myocardial bridging with cardiovascular complications, these findings may have important implications for clinical and surgical practice.