Result: Left ventricular strains decreased gradually according to NYHA and had a moderate to strong correlation with the walking distance of 6 minutes (r = 0.5 - 0.65; p<0.01). Left ventricular strains measured on 3D speckle tracking echocardiography was strongly correlated with GLPS (GLS r = - 0.67; GRS r = 0.80; GCS r = - 0.80; GAS r = - 0.83 with p<0.001), moderately closely correlated with Dd (GLS r = 0.52; GRS r = - 0.63; GCS r = 0.63; GAS r = 0.66 with p<0.05), moderately strongly correlated with EDV (GLS r = 0.52, GRS r = - 0.62; GCS r = 0.61; GAS r = 0.64 with p<0.05), moderately strongly correlated with FS (GLS) = - 0.62, GRS r = 0.72; GCS r = - 0.71, GAS r = - 0.74 with p<0.05).