A coronary computed tomography angiography study on anatomical characteristics of the diagonal branch of anterior interventricular artery.

Abstract

This study investigated the anatomical characteristics of the ramus intermedius (RI) and its correlation with the proximal diameter of the branch vessels of the left coronary artery (LCA) using coronary computed tomography angiography (CCTA). We screened patients who underwent CCTA from January to September 2021 and randomly enrolled 267 with RI (RI group) and 134 without RI (control group). We evaluated the anatomical features of RI (distribution, proximal diameter, length). We measured the proximal diameter of the anterior interventricular branch of the left coronary artery (LAD) and the circumflex branch of the left coronary artery (LCX). We compared the differences between groups in the proximal diameter of LAD and LCX and the correlation between gender and each parameter of the LCA (LAD, LCX, RI) within the RI group. In addition, we compared the correlation between the distribution characteristics of RI and the proximal diameter of LAD and LCX within the RI group. The LAD and LCX proximal diameters in the RI group were significantly smaller than those in the control group (p < 0.05). Comparisons within the RI group showed the following results: the RI distribution, RI diameter and length, and the LCX proximal diameter were not significantly different between male and female patients (p > 0.05), and the LAD proximal diameter was significantly larger in male than in female patients (p < 0.05). There were statistically significant differences in the LAD and LCX proximal diameters between the different RI distribution groups (p < 0.05). Based on the pairwise comparison, there were significant differences in the LAD (LCX) proximal diameter between the RI-beside- -the-LAD (LCX) group and the RI-middle group, as well as between the RI-beside- -the-LAD (LCX) group and the RI-beside-the-LCX (LAD) group (p < 0.05). A CCTA accurately evaluated the anatomical characteristics of an RI, which has an impact on the proximal diameter of the branch vessels of the LCA (i.e. LAD and LCX), the degree of influence of which is correlated with the RI distribution.