Correlation of left ventricular mass determined by echocardiography with vectorcardiographic and electrocardiographic voltage measurements.

Left ventricular mass, derived from echocardiographic measurement of left ventricular wall volume, was compared with simple vectorcardiographic and electrocardiographic voltage measurements in 36 patients with left ventricular enlargement and 7 normal subjects. Left ventricular wall volume was obtained by subtracting the volume of the ventricular cavity, calculated as the cube of the ultrasound internal dimension, from the volume occupied by ventricular wall and cavity, calculated as the cube of the internal dimension plus twice the wall thickness. This method differs from those used hitherto and appears preferable on theoretical grounds. The mass measurements correlated closely with the vectorcardiographic horizontal, and summed horizontal and sagittal, maximum QRS vectors (r= go9) and less closely with Sokalow's electrocardiographic criterion (r=0o73). Both the voltage and echocardiographic measurements are useful techniques for assessing left ventricular mass, particularly for serial observations. Where echocardiography is not practicable or available, simple vectorcardiographic measurements offer an alternative means of estimating left ventricular mass.