Glenn shunt: A surgical operation for children born with cyanotic heart disease ("blue babies"), in which a large vein (the superior vena cava) is anastomosed (connected) to the right pulmonary artery so that blood bypasses the malformed right chambers of the heart and is shunted directly into the lungs to be oxygenated.

The operation was created by William W. L. Glenn (1914-2003), then chief of cardiovascular surgery at Yale University. Dr. Glenn invented an early artificial heart using pieces from a child's Erector set, improved the c pacemaker and wrote a standard textbook, "Glenn's Thoracic and Cardiovascular Surgery."