Purpose The present study purposed to investigate the effects of weight loss with LSG on echocardiographic parameters of diastolic dysfunction in subjects with morbid obesity. Methods Sixty-one subjects undergoing LSG for standard indications were enrolled. All subjects underwent a physical examination, electrocardiography, and transthoracic echocardiography before and 6 months after the LSG. Peak early diastolic velocity (E), deceleration time (DT), and peak late diastolic velocity (A) were measured from the transmitral flow signal. Peak early (e ') diastolic mitral annular velocity was measured at the two acquisition sites (basal septal and basal lateral) using the tissue Doppler recordings. Results A significant improvement was observed in echocardiographic measures of the diastolic function includingE/Aratio,E/e ' ratio, DT, and isovolumic relaxation time (IVRT) from baseline to the postoperative 6 months. Left atrial volume index (LAVI) reduced from 30.3 +/- 3.9 ml/m(2)to 28.0 +/- 3.3 ml/m(2)(p < 0.001). In addition, interventricular septum diameter (IVSD) significantly decreased from 11.3 +/- 1.3 mm to 10.2 +/- 1.1 mm (p < 0.001). The change in BMI was significantly correlated with the improvements in DT (r = 0.334,p = 0.012),E/e ' (r = 0.440,p = 0.001),E/A(r = - 0.317,p = 0.017), and IVRT (r = 0.348,p = 0.008). Conclusion LSG leads to a significant improvement in echocardiographic measures of the left ventricular diastolic function in subjects with obesity. Our findings also show that LSG leads to a reverse remodeling indicated by the decrease in interventricular septum thickness and left atrial volume index in this population.