Limitations
The major limitation of our study is that we included only isolated severe MS patients and hence our results are not applicable to patients with multi-valvular disease or other valve disease. This was done so as to have a uniform study population as including subjects with regurgitant lesions would have resulted in volume overload of the left atrium thereby affecting the results. Secondly our results are not applicable to patients in AF as they were excluded. This was because the speckle tracking echocardiography is ideally for patients with regular heart rhythms as strain values are directly influenced by the length of diastole. Thirdly, image quality and different vendor machines as well different versions of software of the same vendor may affect the results. However, the same equipment and software were used to assess all study subjects thereby avoiding any inconsistency in measurements. Fourthly invasive cardiac catheterization was not done in our study. This was because two-dimensional echocardiography is standard technique to evaluate patients with rheumatic MS. Lastly we did not study the effect of BMV on LA strain parameters which requires further investigation.