Left ventricular volume

The QRS amplitude, duration, and mean axis direction of the standard 12-lead elec-trocardiogram were compared with left ventricular mass, volume, wall thickness, and stroke work in 112 adult patients. These patients had normal left ventricles or various degrees of left ventricular dilatation or hypertrophy. Left ventricular volumes and mass were determined by a quantitative angiocardiographic method. A significant but not a close correlation between left ventricular mass and ECG voltage was found. End-diastolic volume, stroke volume, stroke work, wall thickness, and "total left ventricular volume " (volume of left ventricular muscle and cavity at end-diastole) had generally lesser degrees of correlation with the QRS amplitude than did the mass alone. Sub-grouping of patients into those with pressure overload on the left ventricle, volume overload, aortic valve disease, or anatomic left ventricular hypertrophy did not improve correlations. The left ventricular hypertrophy voltage criteria of Sokolow and of Grant were assessed; respectively, 68 % and 67 % of 75 patients with anatomic hypertrophy had hypervoltage. The direction of the anatomic long axis of the left ventricle was not significantly related to the mean QRS-vector direction