En Bloc Rotation

Also known as: en bloc rotation of the outflow tracts, en block rotation

What is en block rotation?

Transposition of the great arteries (TGA) is a rare congenital heart defect where the connections between the heart and the aorta and pulmonary artery are reversed. TGA is often present along with other heart defects. En bloc rotation of the outflow tracts is a surgical procedure that can be used to correct some complex cases of TGA.

What happens during the procedure?

En bloc rotation is a major open-heart surgery that is performed under general anesthesia and requires a multi-day stay in the hospital. It involves the removal and reimplantation of both major arteries that connect to the heart, as well as other heart repairs.

Is any special preparation needed?

Your child will likely need to undergo several diagnostic tests to determine if they are a candidate for en bloc rotation. Your doctors may have other guidance depending on the specific nature of the procedure. For example, you may need to avoid food and medication for a period of time before the procedure.

What are the risk factors?

An en bloc rotation is a major, complex procedure that does pose risks, so it’s important to discuss these risks and potential outcomes with your doctors. Despite the risks, in many cases it’s the best treatment option available for the infant with a congenital heart defect, and many children who have undergone the procedure go on to lead healthy, productive lives.

Reviewed by: David Kalfa, MD

This page was last updated on: June 26, 2026 02:54 PM