The Electrocardiogram in Patients with Both Great Vessels Arising from the Right Ventricle Combined with Pulmonary Stenosis

Abstract
An ecg study of 22 patients in whom both great vessels arise from the right ventricle combined with pulmonary stenosis revealed an almost constant association of right atrial enlargement, of intraventricular conduction disturbances and of severe right ventricular hypertrophy. A large number of patients also showed signs of left ventricular hypertrophy and of delayed atrio-ventricular conduction time. This study also demonstrated the great value of the ecg in the differentiation of this malformation from tetralogy of Fallot. The 3 most important findings in the differential diagnosis are left ventricular hypertrophy, complete right bundle-branch block and first degree atrioventricular block; none of these features is usual in a tetralogy of Fallot The ecg features were discussed in relation to the hemodynamics. The unusually high incidents of complete and incomplete right bundle-branch block was related to the extreme overloading of the right ventricle that in this malformation occurs during systole.