[Coronary CTA evaluation of the relationship between mitral valve annulus and coronary circulation: implications for percutaneous mitral annuloplasty].

PURPOSE: To evaluate anatomical relationships between mitral annulus (MA), coronary arteries and coronary sinus (CS) in two groups of patients with and without moderate mitral insufficiency on coronary CTA to identify candidates to percutaneous mitral valve annuloplasty via the coronary sinus without risk of coronary artery occlusion. MATERIALS AND METHODS. Fifty-one ECG-gated coronary CTA examinations, obtained during injection of iodinated contrast material on a 16 MDCT were retrospectively reviewed. The mitral valve annulus diameter, anatomical relationships between CS and coronary arteries and MA-CS distance were compared between both patient groups.

RESULTS: The group with mitral insufficiency included 16 patients and the control group included 35 patients. The AP diameter of the MA was 45,7+/-5,2 mm in the group with mitral insufficiency, significantly larger (p=0.0009) compared to the control group (39,3+/-5,9 mm). In 70.4% of cases, the CS was located next to a coronary artery in an overlapping configuration. The unfavorable anatomical configuration with regards to annuloplasty appeared related to mitral insufficiency (p=0.0539). The distance between MA and CS was greatly variable with the CS routinely extending over the left atrial surface: the distance was significantly (p=0.0002) greater for all patients along the posterior surface (8,1+/-3,8 mm) compared to the lateral surface (5,2+/-4,6 mm) with this différence persisting within both groups: p=0.004 for patients with mitral insufficiency and p=0.0001 for control patients.

CONCLUSION: Our results demonstrate the value of coronary CTA in selecting candidates to percutaneous mitral annuloplasty. In 70.4% of cases, the CS overlaps a coronary artery with risk of compression at the time of annuloplasty.