ECG in DORV

ECG in DORV


ECG in DORV (double outlet right ventricle) varies with the clinical type. In DORV, right ventricle is connected to the aorta and faces systemic pressure. Hence features of right ventricular hypertrophy is almost uniformly present in all types of DORV. Since both great vessels arise from the right ventricle, a ventricular septal defect is obligatory. If the ventricular septal defect is small we can expect pressure overloading of the left ventricle. When the ventricular septal defect is large, in the absence of pulmonary stenosis or pulmonary vascular obstructive disease, pulmonary blood flow is increased and there will be left ventricular volume overload. But a study by Krongrad E et al. showed that the predictive value ECG in DORV is low.1

In tetralogy like DORV which has a subaortic ventricular septal defect with pulmonary stenosis, the ECG shows right axis deviation.
TGA like (transposition like) DORV has a subpulmonic VSD without pulmonary stenosis. In this type, ECG shows left ventricular volume overload and right axis deviation. Left ventricular volume overload is manifest as tall R waves with deep narrow Q waves  lateral leads.
VSD like DORV has subaortic ventricular septal defect with no pulmonary stenosis. This condition has left ventricular volume overload on the ECG with left axis deviation.

Reference

  1. Krongrad E, Ritter DG, Weidman WH, DuShane JW. Hemodynamic and Anatomic Correlation of Electrocardiogram in Double-Outlet Right Ventricle. Circulation. 1972;46:995-1004.