Can anatomical left ventricular mass be estimated reliably by M-mode echocardiography? A clinicopathological study of ninety-three patients.

To evaluate the accuracy of M-mode echocardiography in the assessment of left ventricular mass, we compared various echocardiography-derived regression equations for left ventricular mass to postmortem left ventricular weights in 93 patients (mean age 68 +/- 11 years) who had autopsy within 30 days of technically adequate two-dimensional guided M-mode echocardiography and who had normal left ventricular shape. The left ventricle was enlarged in 36 patients (39%) and was involved by chronic ischemic disease in 48 patients (52%). Only a modest correlation was found between M-mode echocardiography and anatomical left ventricular mass (range of correlation coefficients, 0.58 to 0.67). Each echocardiographic formula demonstrated increasing deviations as left ventricular mass increased. A previously suggested correction formula lessened overestimation, but considerable data dispersion remained. Regional wall-motion abnormalities, present in 22%, did not affect the correlation. We conclude that M-mode echocardiography, performed with standard methods, does not reliably estimate anatomical left ventricular mass, especially in patients with large hearts.