Relationships between coronary arteries and atrioventricular annuli: surgical and percutaneous implications.

Objective: Atrioventricular valve surgery poses a risk of myocardial infarction due to the proximity of the coronary arteries. Percutaneous techniques also present a risk of coronary injury. Our objective was to identify, on the mitral and the tricuspid annuli, the zones of high risk given their proximity to the circumflex artery and the right coronary artery, respectively.

Methods: We dissected the courses of the circumflex artery and the right coronary artery in 25 explanted hearts. The distances were measured at reference points according to a clock-face model. Proximity was "very high", "high", or "relative" for distances of less than 5 mm, between 5 and 10 mm, or more than 10 mm, respectively.

Results: The mitral annulus zone of "high" proximity was located between "7:30" and "10:00" (minimum 6.5 mm at "9:30"). The tricuspid annulus zone of "very high" proximity was located between "1:30" and "3:00" (minimum 4.0 mm at "2:00"). The circumflex artery seemed closer to the mitral annulus in the hearts with left coronary dominance (n = 2), emphasizing the importance of the preoperative coronary angiography.

Conclusions: Zones at risk of coronary damage were identified on the mitral and the tricuspid annuli between "7:30" and "10:00", and between "1:30" and "3:00", respectively. Knowing them can help interventionists avoid ischemic complications. Based on an innovative clock-face orientation scheme in which the distance data were collected at multiple reference points on a superimposed template, our study provides an intuitive and detailed overview of the critical distances between valves and arteries.