What structure courses through the Posterior Interventricular Groove?

The structure that courses through the Posterior Interventricular Groove is the Middle Cardiac Vein. This groove, also known as the posterior interventricular sulcus, is located on the heart’s posterior side and demarcates the left and right ventricles.

The Middle Cardiac Vein collects deoxygenated blood from the areas supplied by the posterior descending artery, which primarily irrigates the inferior aspects of the heart. It runs in this groove alongside the posterior interventricular artery, eventually draining into the coronary sinus, which is the large vessel that collects blood from the heart muscle and returns it to the right atrium.

This understanding of blood flow and the anatomical relationship between the cardiac veins and the arteries is critical for interpreting echocardiography and assessing cardiac function.