Doppler M-mode distinguishes between restrictive cardiomyopathy and constrictive pericarditis

Color Doppler M-mode echocardiographic imaging of the left ventricular posterior wall is seen in row 1, the calculated Doppler myocardial velocity gradient (MVG) is in row 2, and the corresponding transmitral pulsed-wave Doppler blood flow is seen in row 3. Panel A is from a patient with a restrictive cardiomyopathy (RCM), panel B is from a patient with constrictive pericarditis (CP) who has marked respiratory variation of blood flow (>25 percent E-wave reduction in inspiration), and panel C is from a patient with constrictive pericarditis and absent respiratory variation (nondiagnostic E-wave reduction in inspiration). Arrows seen in row 2 indicate peak values of the MVG in the predetermined phases of the cardiac cycle. The rapid ventricular filling (RVF) MVG was 3 times higher in both CP patients (* in row 2, panels B and C) compared with RCM patient (panel A), and the isovolumic relaxation (IR) MVG was positive in RCM patient and negative in both CP patients (# in row 2, panels B and C).