Which coronary artery is primarily responsible for supplying the bundle of His and bundle branches?

The bundle of His and the bundle branches are crucial components of the heart's electrical conduction system, responsible for transmitting impulses that coordinate heart contractions. The primary supply of blood to these structures comes from the left coronary artery, specifically through its branches.

The left coronary artery bifurcates into the left anterior descending (LAD) artery and the circumflex artery. While the LAD does supply parts of the interventricular septum and, hence, supplies the bundle branches to a degree, the overall contribution to the bundle of His is more accurately attributed to the right coronary artery in most individuals, particularly in right dominant coronary systems, as it supplies the lower septal area as well.

However, choices regarding the most common pattern can be nuance-dependent in specific patient populations or individual anatomy variations, which is useful to consider in clinical practice.

Understanding the vascular supply and anatomy of the heart is key for managing patients with various cardiac conditions, especially in the context of ischemic heart disease or following myocardial infarction, where the blood supply to these conduction pathways can be compromised.