Arterial supply of the posterior interventricular sulcus: A CT coronary angiographic study

Objective: The objective of this study was to determine the different vascularization patterns of the posterior interventricular sulcus (PIS) with coronary CT angiography. Materials and methods: Three hundred and fifty-six coronary CT angiograms (CCTA) were retrospectively analyzed in 248 men and 108 women (mean age, 54.9 years ± 13.6 [standard deviation]). The PIS was divided into three segments from the crux cordis to the notch of the cardiac apex according to the American Heart Association classification (basal, mid ventricular and apical), and the artery or arteries supplying each segment were recorded. The relative frequency of the different vascularization patterns was calculated and the distribution of dominance types was recorded. Results: Blood was supplied to the PIS by one or more branches of the right coronary artery (RCA), the left circumflex artery (LCX), or the left anterior descending artery (LAD). We observed 25 different irrigation patterns. In the most frequent pattern (31.3%), the basal and mid-ventricular segments were perfused by a single arterial branch originating from the RCA at the crux, and the apical segment was perfused by the LAD traveling beyond the notch of the cardiac apex and entering the posterior interventricular sulcus. Of the 356 cases, the circulation was right dominant in 310 (87.1%), left dominant in 34 (9.5%), and balanced in 12 (3.4%) cases. Individual segments were perfused by a single artery in 288 (80.9%) cases, and by more than one in the remainder. Conclusion: CCTA allows detailed assessment of the arterial supply of the PIS, and allowed to describe 25 subtypes. This information is of potential value to both cardiac surgeons and interventional cardiologists who plan bypass surgery or angioplasty aiming at the posterior interventricular artery.