الفهرس 
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Abstract
Rheumatic heart disease (RHD) is one of the most common forms of cardiac diseases worldwide, particularly in developing countries, where it remains the second most common cause of LV torsion increases with increasing preload and vice versa (Reisner et al., 2004).
Despite that some reports suggested that STE derived LV mechanics are worsened in MS compared to controls, little is known about the immediate effect of balloon mitral valvuloplasty (BMV) in patients with MS on the systolic performance of the LV (Buchalter et al., 1994; Buckberg, 2002).cardiovascular morbidity and mortality after atherosclerotic vascular disease (Pastore et al., 2011).
Mitral stenosis (MS) is one of the most common valve lesion seen in chronic RHD and usually manifests with exertional dyspnea and features of right heart failure resulting from pulmonary venous, and subsequently pulmonary arterial, hypertension. Unlike the other commonly encountered valve lesions (mitral regurgitation, aortic stenosis, and aortic regurgitation), MS does not produce any significant hemodynamic load on the left ventricle, and therefore, left ventricular (LV) systolic dysfunction is believed to be an exceedingly uncommon occurrence in patients with MS (Heller and Carleton, 1970).
With the recent introduction of speckle tracking echocardiography technique (STE), the appreciation of LV systolic dysfunction before they manifest as a decrease in LV-EF became possible. Mechanically, the myocardial fibers deform in the form of longitudinal and circumferential shortening and radial thickening, in addition to the opposite rotations of the LV apex and base that result in a wringing motion, i.e. LV twist or torsion. All deformational behaviors of the myocardium can be appreciated by STE. LV torsion is of particular importance for systolic ejection and recoil of torsional forces (untwist) creates negative suction pressures and thus is important for diastolic filling. LV torsion is load dependent and, with constant afterload,