Health Science Reviews

by Lutho Daza

OUTLINE

In this article, the researchers from the College of Health Sciences, Westville Campus in Kwazulu-Natal, conducted a study with the aim of answering the relationship between the morphology of the right coronary artery (RCA) and left coronary artery (LCA), which included the shape and the branching patterns of the RCA. In addition, the occurrence of a double RCA and the absence of the LCA using coronary angiograms.

The study was conducted to document the anatomical variations of the coronary artery. The RCA gives off the posterior intervertebral artery (PIB) with a dominance of 60%, and the codominance of 2.5% occurs when the circumflex branch (CX) and RCA provide the PIB. The presence of rare congenital anomalies of the coronary artery splitting. The geometric shape of the RCA is C-shaped and sigma-shaped, with the C-shape mostly associated with Atherosclerosis in their proximal middle region. The isolated absence of LCA occurs when the anterior intervertebral artery (AIB) and CX arise directly from the left aortic sinus rather than bifurcating from a common trunk. The occurrence of the AIB and CX outside the LCA is known as a secondary absence of LCA.

    METHODS

500 human coronary angiograms acquired from the cardiac catheterization of a private hospital in KwaZulu-Natal were reviewed. The branching pattern of RCA was classified into type A where a single RCA was present, type B where RCA dominance with left dominance, type C where RCA splits with co-dominance and type D where RCA splits with right dominance.

LCA was classified into type A where LCA is bifurcated into AIB and CX, type B, trifurcation into AIB, median, and CX arteries, type C is quadrifurcation into AIB, two median arteries, and CX artery, type D AIB and CX originate from aortic sinus and LCA is absent and type E the LCA is absent, AIB, median and CX arteries arose from left aortic sinus. The shape of RCA was classified as either C-shaped or S-shaped.

    RESULTS

RCA type A was the most prominent with 95.8% and a split of 4.2% of cases. RCA type B occurred in 3.6%, type C occurred in 0.4% and type D occurred in 0.2% of the study sample. LCA type A occurred in 65.8% and type B occurred in 20.4% of the study sample, type C had a prevalence of 1.6%. When LCA was absent, LCA type D occurred in 10.8% of cases and type E occurred in 1.4% of cases. RCA C-shaped was found in 68% of the heart and S-shaped was found in 32% of the study sample.

In the study, there was a significant correlation between split RCA and absent LCA with splitting of the RCA more prevalent in the absence than the presence of the LCA (Table 1).

Table 1. Data analysis showing results of Pearson chi-square (c2) tests.

LCA- Left coronary artery and RCA- Right coronary artery.

REFERENCE

Singh S, Ajayi N, Lazarus L, Satyapal KS. 2017. Anatomic study of the morphology of the right and left coronary arteries. Folia Morphologica 76(4):668-674.