Acute and short term effects of successful mitral valvuloplasty on net atrio ventricular compliance and its correlation with clinical outcome

AIM OF THE STUDY: Patients undergoing successful balloon mitral valvuloplasty (BMV) have variable improvement in New York Heart Association (NYHA) functional class (FC), exercise capacity (EC) and regression of systolic pulmonary artery pressure (sPAP). Improvement in net atrioventricular compliance (Cn), one of the major determinants of above factors is not routinely assessed. Aim of present study was to assess the change in Cn after successful BMV and its correlation with above factors. METHODS: 50 patients of very severe mitral stenosis in sinus rhythm who underwent successful BMV have been studied. NYHA FC, 6 min walk test (6 MWT) and echocardiographic evaluation was done 24 h before and at 2 weeks, 12 weeks and 24 weeks after BMV. Echocardiographic parameters of patients with improvement in NYHA class of ≥2 (group A) were also compared with those with improvement in NYHA class of ≤1 (group B). RESULTS: Following successful BMV, there was progressive improvement in Cn upto 12 weeks with no further significant improvement till 24 weeks. Change in Cn showed very good correlation with change in NYHA class [r = 0.62, p < 0.01], 6 MWT [r = 0.30, p0.03] and regression of sPAP assessed at 12 weeks and was maintained upto 24 weeks. Change in MVA did not show any correlation with above factors. Group B patients had significantly lower Cn post BMV as compared to group A patients inspite of comparable MVA and trans valvular gradients. CONCLUSION: Improvement in Cn following BMV has good correlation with clinical improvement. So Cn should also be assessed along with MVA to better predict clinical outcome.