Effects of mitral balloon valvuloplasty on left ventricular systolic function in patients with isolated tight mitral stenosis

ABSTRACT

With the advent of mitral balloon valvuloplasty [MBV] in 1984 it became the treatment of choice in well selected patients with mitral stenosis [MS]. This study aimed to find out the effects of MBV on LV systolic performance immediately after the procedure and on short-tern follow-up. Twenty-five patients with severe MS were included in this study [mitral valve area [MVA] of 0.9 +/- 0.14 cm2 and mean transmitral diastolic pressure gradient of 15.5 +/- 5.3 mmHg]. Double balloon MBV technique was used in 88% of these and single balloon MBV technique in the remaining 12%. Patients were evaluated on follow-up by echo Doppler study using Simpson's rule to assess LVEF% as index of LV systolic performance. The mean period of follow-up was 7 +/- 1.7 months. No major complications were found. Increase in the severity of MR by 1 grade or the development of new MR has been developed in 8 patients and regressed on follow-up. ASD was encountered in 5 patients and disappeared by the 3rd month of follow-up. Optimal results were achieved in 22 patients [MVA post MBV > 1.5 cm2] and 3 patients had MVA post MBV < 1.5 cm2. Restenosis developed in 3 patients during the follow-up period and mitral valve replacement [MVR] was offered to them. Subjective improvement by at least 1 NYHA [New York Heart Association classification for Congestive Heart Disease] class in the patient's functional status was observed as early as the first day post MBV which was maintained on follow-up. After MBV, the MVA increased to 1.98 +/- 0.33 cm2 [P < 0.0001] and the pressure gradient dropped to 5.5 +/- 1.6 mmHg [P < 0.0001] and these results were maintained with no significant changes over the period of follow-up. LVEF improved significantly immediately after MBV [p < 0.0001] to 60.6 +/- 5.7% and further significant improvement as noted after 6 months of follow-up [P < 0.05] to 62.7 +/- 6.5%. This functional improvement in LV systolic performance was unaffected by the unwanted sequelae of MBV or the severity of MV morphological abnormalities. It was fair to conclude that in appropriate patients, in skilled and experienced centres, MBV is the procedure of first choice for relief of severe MS and this is associated with immediate as well as short-term improvement in subjective symptoms and LV systolic performance