Utility of Mitral Leaflet Separation Index (Mlsi) For Assesing Severity of Mitral Stenosis Before and After Percutaneous Trnansmitral Commisurotomy(Ptmc)

Background: A novel index called the mitral leaflet separation index (MLS index) has shown to be useful in assessing the severity of Mitral Stenosis (MS). However, studies on use of MLS index in assessing severity of mitral stenosis in post PTMC setting is limited Aims: To study correlation of MLSI with severity of mitral stenosis by various method on echocardiography and catheterization in both pre PTMC and post PTMC setting. Methods: Consecutive patients of all ages and both sexes with moderate to severe rheumatic mitral stenosis who underwent successful PTMC from January 2014 to December 2015 were included in the study. The mitral valve area (MVA) was estimated by the standard 2D echo planimetry and pressure halftime methods. The MLS index was estimated by measuring the maximal separation of tip of the mitral leaflets in end diastole in parasternal long axis (PLAX) view and in apical 4-chamber view (A4C). The MS severity was also assessed by calculating the MVA using Gorlin’s Formula during cardiac catheterization study. Correlation between MLSI and hemodynamic severity of MS by conventional echocardiography and catheterization was studied. Results: 50 patients with moderate or severe mitral stenosis and valve morphology favourable for PTMC were included in the study. The male-to female ratio is 1: 2.33. The mean age of the patients was 30.64 + 10.62 years. Pre-PTMC, the mean MVA by PHT method was 0.749 + 0.12 cm2 while the mean MVA by 2D method was 0.77 + 0.23cm2 . The mean MV pressure gradient was 14.93 + 1.93mmHg and the mean MLSI was 6.606 + 1.5 mm. Mean MVA (Gorlin) was 0.735 + 0.1 cm2 . MLS index correlated well with MVA by planimetry method both in pre-PTMC (r = 0.635; p = <0.0001) and post-PTMC patients (r = 0.49; p = 0.0004) and overall correlation was r = 0.92 with p < 0.0001