A new method for calculating the mass of the left ventricle by angiocardiography

: The authors describe a simplified method to determine left ventricular volume and mass from the ventricular silhouette, taken from a right oblique anterior angiographic projection at 30 degrees, used to measure the telediastolic surface and major axis, and of measuring the telediastolic thickness of the ventricular wall in the postero-lateral segment of the silhouette taken from a left oblique anterior angiographic projection at 60 degrees. Sixty-four ventricular silhouettes were analysed in patients undergoing left kineventriculography for coronaropathy and ventricular mass was determined using both the new and traditional methods. Using the new method mass values (mean value 87.85 g/sq.mt. and SD 34.04) were obtained which were significantly correlated (r = 0.999) with values obtained using the standard method (mean value 88.02 g/sq mt and SD 34.11). The practical advantages of the new method are discussed (simplicity of calculating equation without determining the minor axis of the ventricular silhouette), together with its limits due to the monoplanar technique used to calculate the volume and the measurement of wall thickness in those cases in which the postero-lateral wall is considered the most representative of the mean thicknesses of the left ventricular wall. Lastly, the paper discusses the possibility of applying this method to non-invasive procedures, such as the two dimensional echocardiogram, where more reliable mass values could be obtained even in the event of non-uniform wall thickness.