Significant correlations were demonstrated between echocardiographic measurements of left ventricular wall thickness, right ventricular wall thickness, septal thickness, left ventricular mass, aortic valve excursion, pulmonary valve excursion, mitral valve excursion, and tricuspid valve excursion and the same measurements made directly on the same hearts at autopsy. A new regression formula was derived for the calculation of echocardiographic right ventricular mass in life and was found to correlate significantly with right ventricular mass measured as the sum of right ventricular wall and septal volumes at postmortem examination.