J.J. Watt Reveals He Had Heart 'Shocked Back Into Rhythm' Thursday, Says 'I'm Playing Today'

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Arizona Cardinals player J.J. Watt shared the news that he had an issue with his heart this week, but is doing fine.

The defensive lineman, 33, was listed by the Cardinals' official injury reports as "questionable" for much of the week, though the reports cited a calf injury.

On Sunday, Watt shared on Twitter that he went into atrial fibrillation Wednesday and had treatment for it Thursday. He said that he was getting ahead of the news, which was "leaked."

"I was just told somebody leaked some personal information about me and it's going to be reported on today, he wrote. "I went into A-Fib on Wednesday, had my heart shocked back into rhythm on Thursday and I'm playing today. That's it."

Watt tweeted just hours before he was set to join his team on the field.

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Johns Hopkins Medicine says Afib is Atrial Fibrilation, a type of arrhythmia or abnormal heartbeat. It's caused by faulty electrical signals making the atria contract irregularly and faster than normal. Symptoms include dizziness, fatigue and weakness, and Afib can lead to serious complications like blood clots, heart failure or stroke.

Watt spent last season dealing with injuries and issues, including a shoulder rotator cuff tear. By January, the Arizona Cardinals announced that the team "designated" the star "to return from the injured reserve list."

He was given the clear to return to practice, working his way back onto the roster.

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Watt broke his silence on his injury on Houston teen Maanav Gupta's YouTube podcast, Maanav's Sports Talk in December, according to the Cardinals.

After being told his recovery would take four to six months, he said, " 'Nah, I'm not going to accept that' " and worked with his medical team to expedite his treatment.

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The NFL star posted a shirtless workout snap of himself in June, showing that he'd been working hard.

"No shirt, no shoes, no problem," he captioned the photo on Instagram.

Sharing the same sweaty image on Twitter, Watt — who is expecting his first child with wife Kealia — wrote, "Dad bod loading…"

The NFL chimed in and pointed out the athlete's ripped and muscular physique, joking with Watt, "We calling this a dad bod now, @JJWatt?" to which he replied, "I'm new to this, clearly I've got a lot to learn. Grabbing a beer and a donut now, sliding on some fresh white monarchs and heading out to cut the grass."