Impact of Atrioventricular Compliance on Clinical Outcome of Patients Undergoing Successful Percutaneous Balloon Mitral Valvuloplasty

OBJECTIVE: We aimed to assess the impact of atrioventricular compliance (Cn) on the clinical outcome, after successful percutaneous balloon mitral valvuloplasty (PBMV). METHODS AND RESULTS: Using Doppler echocardiography Cn was estimated from the equation that has been previously validated. Mitral valve area (MVA), tricuspid annular plane systolic excursion (TAPSE), pulmonary artery pressure (PAP), and degree of tricuspid regurgitation (TR) severity were evaluated before, immediately, and every 6 months with a median duration of 32 months after successful PBMV in 150 consecutive patients. An immediate drop in PAP and significant improvement of right ventricle (RV) function was observed after PBMV. Cn was negatively correlated pre and post-PBMV, with the degree of pulmonary artery systolic pressure (PAPs), TAPSE (P < 0.0001). Patients with Cn ≤ 3.75 mL/mmHg had higher incidence of adverse outcome (developing atrial fibrillation [AF], worsening RV function, progressive left atrial dilation, and redo intervention). Multivariate regression analysis showed that the Cn was the strongest independent predictor of PAPs and RV function before and after successful PBMV (P < 0.0001). Cn ≤ 3.75 mL/mmHg was the cutoff value for prediction of clinical events at follow-up. CONCLUSIONS: Atrioventricular compliance was significantly lower in patients with mitral stenosis (MS) with unfavorable outcome after successful PBMV. The RV function and pulmonary hypertension were significantly correlated with the degree of Cn. This suggests a significant role of Cn in patients with MS, providing a good insight for intervention and utilizing Cn as a noninvasive hemodynamic index for risk stratification and proper timing for intervention in patients with MS.