The CEO of United Airlines, who has been on medical leave since suffering a heart attack in October, underwent a heart transplant on Wednesday. The airline said that he was recovering.
United said that it expects Oscar Munoz to return to work this spring. The airline said that a transplant was "considered the preferred treatment and was not the result of a setback in his recovery."
The airline did not provide more details, including where the transplant was performed. It promised to provide more information within 24 hours.
Munoz, 57, became CEO in early September after Jeff Smisek abruptly stepped down during a federal investigation into the airline's dealings with officials who run airports in the New York City area, including Newark, New Jersey, where United has a major hub.
Munoz suffered a heart attack in mid-October, although the company declined to confirm it for several days. At the time, United would only say that Munoz was in the hospital. On Oct. 19, United announced that Munoz would take medical leave, and general counsel Brett Hart was named acting CEO.
In November, Munoz said that after talking with doctors he planned to return to work in the first three months of 2016. On Wednesday, United said it expects him back by the end of the first quarter, March 31, or early in the second quarter.
During his brief CEO tenure, Munoz acknowledged that United had failed its customers by subjecting them to chronic delays and computer outages, and he sought to improve relations with employees.
Munoz was the chief operating officer of freight railroad CSX Corp. before replacing Smisek on Sept. 8. Munoz had previously worked at AT&T, Coca-Cola and PepsiCo and served on the boards of Continental Airlines and, after their 2010 merger, United Continental Holdings Inc.
Chicago-based United is the world's second-largest airline behind American Airlines.