The aim of this study was to determine whether Myocardial Velocity Gradient (MVG) derived from color Doppler Myocardial Imaging can distinguish Restrictive Cardiomyopathy (RCM) from Constrictive Pericarditis (CP). MVG quantifies the spatial distribution of transmyocardial velocities between endo- and epi-cardium. MVG was measured from the left ventricular (LV) posterior wall at end-expiration in diastole during isovolumetric relaxation (IR), rapid ventricular filling (RVF) and atrial contraction (AC). MVG was expressed as 'positive' when subendocardium was moving faster than subepicardium and as 'negative' in the reverse situation.Results: see table (mean +/- SD). * , p < 0.01 compared to CP; , p < 0.01 compared to N by ANOVA. During IR, the subendocarium rather than subepicardium was moving faster in RCM as opposed to CP and N hearts. This finding may be important to better understand the abnormal LV diastolic function in myocardial diseases.Conclusions: The measurement of early diastolic MVG during both IR and RVF would appear to be an accurate variable used to discriminate between RCM and CP.