Echocardiographic measurements of minor axis and wall thickness and calculations from these two measurements of left ventricular end-diastolic volume and mass were performed in 24 patients and compared with angiocardiographic measurements of the same variables in corresponding patients. The echo-measured left ventricular enddiastolic chamber dimension (Dd) correlated closely with the angiographic minor axis in the AP plane (correlation coefficient 0.87 and SE -+-0.45 cm) and with the minor axis from the lateral film (r 0.91, SE +0.39 cm). Similar correlations were found between measurements by these methods of wall thickness (r = 0.89, SE +1.3 mm), of end-diastolic volume (r 0.94, SE ±30.6 cc), and of left ventricular mass (r 0.88, SE +49.19 g). The reproducibility of this method was established by independent recordings and measurements of echo Polaroid films by two observers. The percent systolic wall thickening, as determined by echocardiography, identified subjects with ejection fractions greater or less than 0.50. Echocardiography offers a reliable and reproducible method for measuring left ventricular wall thickness and mass. Finally, ultrasound may provide an accurate method for measuring systolic wall thickening in man. Additional Indexing Words: Chamber dimensions Ultrasound Wall thickness Ventricular mass Ventricular volume A LTHOUGH interest in the thickness of the left ventricle was recorded as long ago as 1724 in pathologic examinations,1 observations on human left ventricular wall thickness and mass in living man have awaited the development of quantitative angiocardiography.2-1 This measurement of left ventricular wall thickness has been related to chamber

Left ventricular end-diastolic and end-systolic volume, stroke volume, and ejection fraction were determined by biplane angiocardiography and echocardiography in 27 patients suspected of having heart disease. Angiographic volumes were calculated by the area-length method and echocardiographic volumes, from the left ventricular dimension of the echograms. The angiographic minor diameter and the semilength correlated significantly with the echocardiographic left ventricular dimensions in diastole and systole. Left ventricular size over a wide range compared favorably by each technique, with a correlation coefficient of r = 0.97 for end-diastolic volume (range by angiography 80-585 ml, see ± 27.76), r = 0.97 for end-systolic volume (range by angiography 24-485 ml, see ± 23.64), r = 0.83 for total left ventricular stroke volume (range by angiography 35-229 ml, see ± 25.45), and r = 0.80 for left ventricular ejection fraction (range by angiography 0.18-0.70, see ± 0.09). These data indicate that left ventricular dimensions in systole and diastole can be reliably determined and left ventricular chamber size and ejection fraction can be quantitated in man by the noninvasive technique of echocardiography.

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It is important to measure the exact volume of 5% dextrose injected when thermodilution cardiac output determinations are made. The marked volume on plastic syringes and their variability may contribute to a small but significant error in the results.