Mitral annular calcification predicts immediate results of percutaneous transvenous mitral commissurotomy

BACKGROUND: Many previous studies have evaluated the impact of mitral valve (MV) deformity scores on the percutaneous transvenous mitral commissurotomy (PTMC) outcome in patients with mitral stenosis; however, the relationship between mitral annulus calcification (MAC) and the PTMC result has not yet been established. The current study aimed to investigate whether MAC could independently influence the immediate result of PTMC. METHODS: Of all patients undergoing PTMC in our institution between April 2005 and November 2009, we included 87 patients (28.7%male, mean ± SD age = 42.8 ± 12.6 years) with rheumatic mitral stenosis who had additional data on the echocardiographic evaluation of MAC along with MV leaflets morphology. Echocardiographic assessments were repeated up to six weeks after PTMC to evaluate the immediate PTMC outcome. The frequency of the optimal PTMC result (secondary MV area > = 1.5 cm(2 )with > = 25% increase and without final mitral regurgitation grade > 2) was compared between two groups of patients with MAC (n = 17) and those without MAC (n = 70). RESULTS: The optimal result was obtained in 55 (63.2%) patients, whereas the result was suboptimal in 32 (36.8%) patients due to insufficient MV area increase in 31(96.9%) subjects and post-procedure mitral regurgitation grade > 2 in 1(3.1%). The rate of optimal PTMC results was less in patients with MAC in comparison to those without MAC (29.4% vs.71.4%). After adjustments for possible confounders such as age and leaflets morphological subcomponents (thickening, mobility, calcification, and subvalvular thickening), MAC remained a significant negative predictor of a suboptimal PTMC result (odds ratio = 0.154; 95%CI = 0.038-0.626, p value = 0.009) together with leaflet thickening (odds ratio = 0.214; 95%CI = 0.060-0.770, p value = 0.018). CONCLUSIONS: MAC appeared to independently influence the immediate result of PTMC; therefore, mitral annulus evaluation may be considered in the echocardiographic assessment of the mitral apparatus prior to PTMC.