Coronary dominance refers the which vessel the posterior descending coronary artery arises from.

In approximately 80% of individuals the posterior descending artery (PDA) arises from the right coronary artery and is referred to as a “right dominant” system. In approximately 10% of individuals the left circumflex coronary artery is considered dominant and it supplies a left posterior descending artery. This is considered a “left dominant” system. The remaining 10% have a “co-dominant” coronary system meaning both the right coronary artery and the left circumflex contribute to the PDA.