Asked by Muzzler
Heart dominance refers to whether an individual heart receives most of its blood from either the right or left coronary arteries.
To determine whether the individual is right or left dominant the pertinent question is: Where does the posterior interventricular artery come from?
Most individuals are right dominant, in which case the posterior interventricular artery arises from the right coronary artery. However, in some individuals, the circumfex artery (LCx) which is a branch of the left coronary artery gives off the posterior interventricular artery, making this an example of a left dominant heart. And in some cases, the anterior interventricular artery (LAD) continues around the apex, turns, and ascends up the interventricular groove as the posterior interventricular artery, which is also an example of a left dominant individual.