Inferior Interventricular Artery

Description

Centered in the posterior interventricular sulcus, the inferior interventricular artery (posterior descending artery) descends toward the apex along the diaphragmatic surface of the heart, running between the right and left ventricles. Proximally, it arises at or near the crux cordis from the right coronary artery in a right-dominant pattern, or from the circumflex branch of the left coronary artery in left dominance, with paired inferior interventricular veins tracking nearby toward the coronary sinus. The vessel lies deep to visceral pericardium (epicardium) and superficial to the inferior ventricular myocardium, with small perforating branches entering the interventricular septum. Adjacent landmarks you would expect in this projection include the right atrium, inferior vena cava entry, and the posterior surfaces of the great vessels at the cardiac base. Coronary dominance and the course of the posterior descending artery drive real clinical decisions. Occlusion here commonly produces an inferior wall myocardial infarction and can extend into the inferior septum, placing the atrioventricular node and proximal His bundle at risk, which is why bradyarrhythmias and varying degrees of AV block often accompany inferior STEMI patterns. This inferior perspective also maps directly onto the standard 12-lead ECG territory (II, III, aVF) and helps correlate angiographic findings with the segmental blood supply of the diaphragmatic myocardium. A small artery with outsized consequences. Use this rendering when you need a clean external roadmap of the coronary circulation for cardiology and anatomy curricula, coronary dominance figures in textbooks, or clinical education on infarct localization and right coronary artery interventions. It also fits well in patient-facing material explaining why lesions at the crux can affect rhythm as well as perfusion. Anatomical accuracy verified by SciePro's Medical Advisory Board.