Non dominant left circumflex coronary artery

Non dominant left circumflex coronary artery

Non dominant left circumflex coronary artery
Non dominant left circumflex coronary artery

Non dominant left circumflex coronary artery seen on left coronary angiogram in right anterior oblique (RAO) caudal view. Non dominant artery is the one which does not cross the crux of the heart to the opposite side. Crux is the junction of the atrioventricular and interventricular grooves on the posterior surface of the heart. The dominant artery supplies the artery to the atrioventricular node (AV node). Some times both arteries can be co-dominant. Regardless of the dominance (whether right or left dominance), it is always the left coronary artery which supplies the major portion of the left ventricular myocardium. LMCA: left main coronary artery (yellow arrow); LCX: left circumflex coronary artery (blue arrow); LAD: left anterior descending coronary artery (black arrow); OM1: first obtuse marginal branch of the LCX (cyan arrow); OM2: second obtuse marginal branch of the LCX (red arrow); Terminal OM: the terminal portion of the LCX continues as the terminal OM (green arrow). Catheter tip (unmarked) is seen engaging the LMCA.

Though a non-dominant left circumflex coronary artery is generally considered to be less significant, sudden cardiac arrest due to acute occlusion has been reported [1]. The patient presented with acute myocardial infarction and new onset atrial fibrillation. Ventricular fibrillation developed suddenly. After resuscitation, coronary angioplasty was done and sinus rhythm restored. They hypothesized that atrial fibrillation in the setting of acute myocardial infarction could have lead to the sudden cardiac arrest.

Reference

  1. Chen HY. Sudden Cardiac Death in a Case of Non-Dominant Coronary Artery Obstruction Without Depressed Left Ventricular Function. Cardiol Res. 2013 Jun;4(3):121-125.