Posterior interventricular artery
The posterior interventricular artery (posterior descending artery - PDA) is a branch of the right coronary artery. It is also commonly referred to as the inferior interventricular branch. This artery runs in the posterior (inferior) interventricular sulcus. Its main function is to supply the diaphragmatic (inferior) surface of the myocardium and interventricular sulcus of the heart.
The posterior interventricular artery can arise from either the left or right coronary artery. The "dominant" coronary artery is the one that gives rise to PDA. In the majority of the population, the right system is dominant, meaning that this irrigates the heart’s diaphragmatic (inferior) surface.
This article will discuss the anatomy and function of the posterior interventricular artery.
|Origin||Right coronary artery (65% of people)|
|Branches||Perforating interventricular septal branches|
|Supply||Diaphragmatic surface of the heart|
Origin and course
In most cases, the posterior interventricular artery originates from the right coronary artery. It arises on the diaphragmatic aspect of the heart when the right coronary artery approaches the crux of the heart. The crux of the heart is the meeting point of the interatrial and interventricular septa of the cardiac chambers. The posterior interventricular artery descends in the interventricular sulcus towards the apex of the heart. When it reaches the apex it anastomoses with the anterior interventricular artery, a branch of the left coronary artery.
The term "dominance" of either side of the coronary arterial circulation is determined by which artery gives rise to the PDA and supplies the diaphragmatic surface of the heart. The right coronary is dominant in approximately 65% of the population. It's important to keep in mind that the term "dominant" is potentially misleading since it can be interpreted as the vessel which irrigates the greater portion of the myocardium. However, it is always the left coronary artery that supplies the greater myocardial portion.
Branches and supply
The posterior interventricular artery supplies the diaphragmatic (inferior) aspect of the myocardium. On its course in the posterior interventricular septum, the posterior interventricular artery gives off several perforating interventricular septal branches. These branches supply the posterior aspect of the interventricular septum.
Learn more about the coronary arteries with our articles, videos, labeled diagrams and quizzes.
- The posterior interventricular artery can originate from either the right coronary artery or from the circumflex artery, a branch of the left coronary artery. In some cases, there can be two posterior interventricular arteries that arise from both the right coronary artery and the circumflex artery.
- Functionally, the posterior interventricular artery can be a terminal or a collateral branch, depending on the anastomoses that this artery forms with the anterior interventricular artery.