Resting echocardiography Doppler echocardiography will be performed on a GE medical Vivid 7 ultrasound machine by a single investigator. Images will be obtained from the parasternal and apical windows. M-mode recordings will be done in the parasternal long-axis view. Pulsed Doppler measurements of mitral inflow will be obtained with the transducer in the apical four-chamber view, with a 1-2 mm Doppler sample volume placed between the tips of mitral leaflets during diastole. Tissue Doppler imagining of the mitral annulus will be obtained from the apical 4-chamber view with a 1.5-mm sample volume placed at the medial and lateral mitral annulus. All Doppler echocardiographic examinations are done with horizontal sweep set to 100 mm/s. At least 3-5 cardiac cycles will be measured. Finally color coded real time tissue Doppler images will be acquired in the apical windows, with the lowest possible depth and smallest angle.