WWE Legend The Undertaker Rushed Into Emergency Heart Surgery Right After WrestleMania 41

Wrestling legend The Undertaker is famous for living through Hell in Cell matches and decades of physical abuse in the ring, but even he and his wife, Michelle McCool, weren't ready for the frightening health ordeal that came after WrestleMania 41.

In an open episode of their Six Feet Under podcast, the WWE Hall of Famer duo shared the behind-the-scenes medical crisis that was almost swept under the rug, and potentially lethal.

WrestleMania Party Turns into Medical Disaster

WWE Legend The Undertaker Rushed Into Emergency Heart Surgery Right

The Undertaker and McCool were in Las Vegas earlier this April to celebrate her WWE Hall of Fame induction, a highlight moment that had The Phenom welcome his bride into the exclusive club. But soon after the pomp, the pair returned home to Texas—and directly into the ER.

"It's because of the heart issues you've been having weeks prior, which, by the grace of god, we found out just by — It ended up being terrifying. The day we got home from WrestleMania, the next day at 6 am, we were at the hospital for a little bit of heart surgery," McCool said, per Newsweek's Andrew Ravens.

What's The Hidden Danger?

The surprising twist? The Undertaker had no clue he was in trouble.

According to Michelle McCool, the routine doctor's checkup in March revealed the Hall of Famer's asymptomatic case of chronic atrial fibrillation (AFib), a dangerous heart rhythm disorder that had gone undetected due to a complete absence of symptoms.

McCool said that the Undertaker had no idea what was wrong with his body. She wondered why he was out of breath while he was just going upstairs or playing with their dog. They never thought it was a heart-related issue.

Inside WWE Icon's Emergency Hospital Stay

Things quickly went into high gear. Following their visit to the hospital, physicians discovered his heart rate was irregular and his ejection fraction, the rate at which blood is propelled out of the heart with each heartbeat, was dangerously low at 30%, according to Bleacher Report.

McCool said that it would be more like 100 percent. During their four-night stay in the hospital, the doctors had to cardiovert him to restore it to a normal rhythm."

But the effects didn't hold. "That sadly lasted, what, 24 hours. Maybe 48. After four days, we go home, two days later, you're back in AFib. Man, I was stressed," McCool added.