Arnold Schwarzenegger, has undergone emergency open-heart surgery, according to US reports.
The 70-year-old underwent the medical procedure on Thursday, according to TMZ.
Schwarzenegger was scheduled to have a catheter valve replacement and developed complications, US reports say.
The procedure usually means the patient can avoid having open-heart surgery.
Doctors at Cedars-Sinai hospital in LA reportedly decided an emergency open-heart operation was needed and Schwarzenegger was in theatre for several hours.
The former governor of California is believed to be in a stable condition.