Real 3D Visualization of the Circumflex Artery Surrounding the Mitral Annulus

The circumflex coronary artery is located close to the mitral annulus. Consequently, it is not immune to iatrogenic damage during mitral valve procedures. Our objective was to visualize the circumflex artery from a surgeon's point of view, emphasizing its proximity. Furthermore, comparing it to coronary angiograms might support preoperative planning.

Ten adult human hearts preserved in 4% formaldehyde solution were investigated (left coronary artery injected with contrast agent). After performing coronary angiographies from LAO (left anterior oblique) 40/cranial 20, RAO (right anterior oblique) 10/cranial 40, and true lateral projections, anatomical preparations were performed. Images were captured throughout the full course of the circumflex coronary artery from multiple angles. Finally, the mean distances were measured in every 5 mm between the investigated artery and the annulus of the mitral valve.

Three-dimensional model of the circumflex coronary artery and its surroundings was successfully achieved from a left atrial surgical viewpoint. The main branches were identified on the coronary angiograms. The closest distance was measured under the region of the left auricle (2.02 ± 0.69 mm; 1-3.1 mm). Afterward, the circumflex artery was observed to make a loop away from the annular region.

Our observations show correlation with previous anatomical studies and case reports addressing iatrogenic lesions on the circumflex coronary artery. Based on all these, we could determine a "danger zone" on the vessel. The simultaneous evaluation of the anatomical preparations and the angiograms might improve the acknowledgment of this vulnerable region serving to avoid any damage to the coronary artery.