Masters of Clinical Anatomy Projects
The circumflex artery (CX) lies in the left atrioventricular groove, running intimately parallel to the mitral annulus. Thus, unintentional damage to the CX can occur during mitral valve surgery, typically reported in hearts with a left dominant circulation. This study aims to elucidate the anatomical CX-annulus relationship with respect to dominance, and evaluate unintentional CX damage following three surgical repairs. Using cadaveric hearts (n=27), coronary circulation was dissected and dominance assigned. Following a left atriotomy, a clock face was overlaid on the mitral valve (12:00 positioned at A2 leaflet midline) and the CX-annulus distance was measured at each hour. The CX-annulus relationship was closest in left dominant hearts, with most (n=4) having a CX that hugged the posterior length of the annulus, diving deep at 3:00 (before the posterior commissure), a novel finding. Although surgical damage was independent of dominance, mitral valve repairs caused significantly greater severity of damage (p<0.05).