This type of tracing, with voltage criteria for left ventricular hypertrophy but without QRS prolongation or repolarization (ST segment and T wave) changes, is somewhat characteristic of a volume overloaded left ventricle such as occurs with aortic or mitral insufficiency. Cardiograms which demonstrate more marked changes in QRS duration and in the ST segment and T wave, as shown in the first three tracings, are somewhat more characteristic of a pressure overloaded ventricle such as occurs with systemic hypertension, aortic stenosis and the hypertrophic cardiomyopathies.