Double outlet right ventricle (DORV)

Double outlet right ventricle (DORV)

Double outlet right ventricle is a cyanotic congenital heart disease in which pulmonary artery and aorta arises from the right ventricle. According to surgeons’ definition, even an aortic override of more than 50% qualifies for a diagnosis of DORV. Left ventricular blood can move out only through the ventricular septal defect. Aorto mitral continuity is absent and there is subpulmonic as well as subaortic conus.

In about two third of cases the aorta and pulmonary artery have a side by side relationship with aorta to the right of the pulmonary artery. In about a quarter of cases aorta is anterior and to the right of pulmonary artery. In a few cases the aorta is to the left and anterior to pulmonary artery. In still fewer cases, a normal great artery relationship with aorta arising to the right and posterior to pulmonary artery is seen.

In majority of cases, the ventricular septal defect is subaortic and causes a streaming of left ventricular blood into the aorta. The desaturated blood reaching the right ventricle thus preferentially goes into the lungs through the pulmonary arteries for oxygenation. The systolic pressures in the aorta and right ventricle are usually systemic. Pulmonary stenosis is a common association of DORV and the features resemble that of tetralogy of Fallot in this case.

If there is no pulmonary stenosis, the pulmonary artery systolic pressures are also systemic and the clinical picture resembles that of a VSD with left to right shunt. These patients are at risk of developing obstructive pulmonary vascular disease.

Taussig-Bing anomaly is a variety of DORV in which there is a subpulmonic VSD and the left ventricular blood is shunted to the pulmonary artery and the desaturated blood is shunted to the aorta. This causes significant cyanosis and heart failure. The clinical picture resembles that in transposition of great arteries.