Double-outlet right ventricle (DORV)

Overview

Double-outlet right ventricle (DORV) is a congenital heart defect where two major arteries, the aorta (which carries blood to the body) and the pulmonary artery (which carries blood to the lungs), are not connected as they should be in the heart. Normally, the aorta connects to the left lower heart chamber, while the pulmonary artery connects to the right lower chamber. But in babies with DORV, both arteries partially or fully connect to the right lower heart chamber, creating a hole between the lower chambers called a ventricular septal defect (VSD). This leads to a mixing of oxygen-rich and oxygen-poor blood, causing symptoms like skin discoloration.

Symptoms of DORV usually appear in the first few weeks after birth. Most infants born with DORV need open-heart surgery within their first year to fix the heart’s malformation and improve blood flow. Additionally, DORV can sometimes occur along with other heart issues, like additional defects or problems with heart valves or blood vessels. This makes it important for affected infants to receive comprehensive medical evaluation and treatment.

In DORV, there’s always a VSD (hole in the septum between the ventricles). This hole allows blood to flow between the ventricles. DORV can be categorized based on the location of the VSD:

• DORV with subaortic VSD: In this type, the VSD is right under the aorta.
• DORV with subpulmonary VSD (Taussig-Bing Anomaly): Here, the VSD is located under the pulmonary artery.
• DORV with doubly committed VSD: This variation involves a VSD positioned under both major arteries, the aorta and pulmonary artery.
• DORV with non-committed (or Remote) VSD: In this case, the VSD is not close to either the aorta or the pulmonary artery.

Symptoms

Symptoms of DORV (Double Outlet Right Ventricle) typically become noticeable shortly after birth and resemble those of other congenital heart conditions. These signs may include:

• Bluish or purplish skin, lips, or nails (cyanosis).
• Rapid breathing (tachypnea) or difficulty in breathing.
• Feeding difficulties and poor weight gain.
• Detection of a heart murmur by a healthcare provider using a stethoscope.
• Excessive sweating, especially during feeding.
• Elevated heart rate (tachycardia), exceeding 100 beats per minute.
• Unusual sleepiness or appearing lethargic.

In addition to these symptoms, infants with DORV may have other associated congenital issues, such as:

• Ciliary dysfunction, affecting tiny hair-like structures in the airway.
• Heterotaxy, where organs in the chest and abdomen are not in their usual positions.
• Intestinal malrotation, involving abnormal twisting of the baby’s intestines.
• Pulmonary stenosis, which is a narrowing or stiffening of the pulmonary valve, situated between the right ventricle and the pulmonary artery.
• Ventricular hypoplasia, where one or both ventricles are smaller than normal.

Causes

The exact cause of DORV is not fully understood, but it can occur in babies with chromosomal abnormalities.