Concerns for the endangered species of Sumatran orangutan at a time when routine open heart surgery was being performed in human babies, combined with a collaboration between the San Diego Zoo and UC San Diego Health, led to the planning of repairing the large hole in the heart in two-year-old Karen.

[2] Karen, also known as "Kare-Bear",[4] a Sumatran orangutan,[3] was born at the San Diego Zoo on 11 June 1992 to nine-year-old mother Karta and father Otis.

[6] Karen was found to have a heart murmur at a health check-up at the age of two,[7] after it was noted that she was not growing at the appropriate speed.

[3][6] A surgical team led by cardiothoracic surgeon Stuart W. Jamieson from UCSD repaired the defect by opening Karen's chest and heart and stitching the hole to close it.

The whole procedure required the co-operation of a number of surgeons, nurses, anaesthetists, medical technicians, veterinarians and animal keepers and lasted seven hours.

[9] Although she suffered a lung complication, it was managed successfully[6] and she survived to make headlines, receiving get-well cards from all over the world.