What is the term for the "third coronary artery" that has been reported in some individuals?

The term "third coronary artery" is commonly referred to as the ramus artery. This artery can be seen variably in the population and is considered an anatomical variant. It typically arises from the left main coronary artery and supplies blood to parts of the lateral wall of the left ventricle, effectively serving a role similar to that of the circumflex artery.

Understanding the ramus artery is important in the context of coronary artery disease and procedures such as coronary artery bypass grafting. The presence of a ramus artery can influence surgical approaches and the interpretation of coronary angiograms since it may alter the normal anatomical understanding of coronary circulation.

The marginal artery, on the other hand, refers to an artery that runs along the margin of the colon and is not related to coronary anatomy. An anomalous artery indicates an abnormality but does not specify the typical role or function associated with coronary system variations. The circumflex artery, while a significant component of the coronary system, is not classified as a "third coronary artery" but as one of the primary vessels supplying the heart.