Arnold Schwarzenegger reportedly underwent heart surgery on Thursday.

TMZ first reported that the 70-year-old star went to the hospital for an experimental procedure to replace a catheter valve in his heart. The outlet reported that complications arose and open-heart surgeons took over. But according to Daniel Ketchell, Schwarzenegger's spokesman, "it wasn't an emergency."

"It was a planned surgery," he told The Associated Press. "The open heart was the backup option."

"Schwarzenegger underwent a planned procedure at Cedars-Sinai to replace a pulmonic valve that was originally replaced due to a congenital heart defect in 1997," Ketchell said in an earlier statement. "That 1997 replacement valve was never meant to be permanent, and has outlived its life expectancy, so he chose to replace it yesterday through a less-invasive catheter valve replacement. During that procedure, an open-heart surgery team was prepared, as they frequently are in these circumstances, in case the catheter prodedure was unable to be performed. Governor Schwarzenegger's pulmonic valve was successfully replaced and he is currently recovering from the surgery and is in stable condition."

The rep also claims that the star is in good spirits, even invoking his famous "Terminator" catchphrase upon waking up: "I'm back."

In 1997, he reportedly underwent a different heart surgery to replace an aortic valve. At the time, he said the condition was congenital and had nothing to do with possible steroid use.

In 2016 the star opened up about his past heart surgery in an interview with Graham Bensinger.

Earlier this week, the former California governor spoke to CNN about the changes in the Republican party, noting that its alleged lack of diversity and ability to reach across the aisle are leading to decreased numbers.

“Since then the party has decreased and now has only a 26 percent popularity overall and so it is dying and I see it like the Titanic,” he said. “The only thing is that we don’t have to go under completely. We don’t have to wait for that moment. Let’s change and let’s go and be more open and go back to this kind of like big tent idea of Ronald Reagan.”

The actor has been an occasional critic of the Trump administration and has a unique tie to the president as he took over for him after NBC's brief revival of "Celebrity Apprentice."

Reps for Schwarzenegger did not immediately respond to Fox News' request for comment.

The Associated Press contributed to this report.