Studies on the Genesis of Late R Waves in Right Chest and Intracardiac Leads

Abstract

The significance of late or secondary R waves is studied on ninety subjects with miscellaneous electrocardiographic patterns including the normal by means of intracardiac electrocardiography. In classical right ventricular hypertrophy and complete right bundle branch block, late R waves can be attributed to a delay in activation of the right ventricular free wall. In the other patterns including a part of incomplete right bundle branch block, activation of the left ventricular posterior base constitutes these late R waves.