Variations in the anatomical origin and distribution of coronary artery among black African population: a cadaveric study in western Kenya.

Abstract

The coronary artery and its branches is the main blood vessel that supplies the myocardium. The principal branches of ascending aorta are the right and left coronary artery. Variations of the coronary arteries are vessels that do not conform to the normal anatomy of coronary arterial branching tree. These variations can be compensatory, collateral, alternate or a duplication of another vessel and can have both positive or negative attributes. Cardiac dominance is depicted with the artery that gives rise to the posterior descending artery which is key in the perfusion of the intraventricular septum. Social demographic factors may influence diseases like diabetes and hypertension due to these variations. Variations in coronary arteries are thought to be among the leading cause of sudden death thus giving cardiologists and heart surgeons challenges during the management of heart conditions. This study sought to determine these variations among the black African population in Western Kenya by assessing the variations in origin and distribution of the principal coronary arteries, investigating the dominance of the heart and associating the variations to demographic characteristics of the study population. Crossectional study design was adopted. The study sites were Maseno University, Uzima University and Masinde Muliro University anatomy laboratories. The sample size of 89 cadavers was estimated using Crochan’s formula leading to 72 samples in total. Data sheets were designed to capture the variables while descriptive statistics was used to determine the mean, mode, median and standard deviation of the variations. Chi square test was used to test the association between the right, left and co dominance while Pearson’s correlation test was used to analyze the relationship between the variables with a P ≤ 0.05 considered as significant. All ethical considerations were observed. Luo were the leading ethnic group in the study ethnicity at 54.2% while being the Kuria and Kalenjin were the lowest and at 2.8%. Dual aortic origin had the most common occurrence at 55.6%. Both coronary arteries showed bifurcation with a mean length of 12.22cm on the right artery and 9.32mm on the left. Termination of the left coronary artery was at the crux while on the right coronary artery was between the crux and the obtuse margin of the heart. There was right dominance of the heart with statistical significance between gender and right heart dominance at P ≤ 0.0260. There was no statistical significance between gender and ethnicity to the variations There were variations in the origin of the coronary artery with right dominance being more expressed. Population specific variation like race and geographical location to be considered for further study.