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Post-Heart Attack, Tim O’Donnell Will Return to Racing

His genetic predispositions put O'Donnell at risk for a 'widowmaker,' but now he says he's been cleared for a return to full training.

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After being cleared by his doctors, Tim O’Donnell, runner-up at the 2019 Ironman World Championships, says he’ll return to racing next year. Speaking to us earlier this week, he also shared some details about what led to his surprise heart attack while racing Challenge Miami back in March.

“I got the green light from a performance standpoint,” he said about moving forward with training. O’Donnell shared his updates in a Youtube video, which follows him through his various tests with specialists and his “return” to training. (You can see the full video below.)

Two weeks ago, O’Donnell made a trip to Massachusetts General to visit renowned cardiologist Aaron Baggish, who serves as the head doctor for the Boston Marathon. They did a modified treadmill stress test (modified to go fast enough for O’Donnell), a VO2 max test to look at the ratio of gases (which can help determine heart function), and an EKG. The good news: there’d been no muscle damage to his heart function from the heart attack, and he also now knows how to manage his genetic risk factors. Because it was such an acute event and not a chronic heart condition, he said, the concern was more about making sure there was no damage and that the underlying issues were addressed.

“The risk isn’t any more now than it was when we found out about this,” he said. In fact, because he’s had his artery reinforced now by a stent and because he had a genetic predisposition to this specific type of blockage, meaning it could have happened at any point, he said, in some ways he’s actually oddly better off now than when he didn’t know what was going on.

O’Donnell’s goal is to be on the start line at the Ironman World Championships in October 2022. But first, he said, he has to get back to fitness—after months of keeping his heart rate below 150 and being nervous about training solo—so that he can then start 2022 with normal training.

“I’m definitely out of shape,” he said. He’s been focusing on getting his health in order, supporting his wife, Mirinda Carfrae, in her return to racing post-childbirth, and spending time with his family.

The news of the heart attack, which he shared in August, took the triathlon community by surprise. O’Donnell, it turned out, had suffered what’s known as a “widowmaker,” a blockage of the left anterior descending artery (LAD). By the time he arrived at the hospital post-race, his LAD was nearly 80% blocked after an artery rupture. He was lucky to be alive.

The news prompted concern throughout the triathlon community about what could cause such a devastating event for one of the fittest athletes in the world.

After extensive testing and consulting with a number of top cardiologists, O’Donnell said it’s clear it was caused by a few factors. He has several genetic risk factors, which increased the plaque and inflammatory response in his arteries. The stress of years of intense pro-level training also increased the inflammation and could have contributed to the cardiac event—but his fitness may have saved his life too, he said.

O’Donnell said he was feeling “off” last year, experiencing palpitations and having trouble breathing during races in late 2020. But initial tests showed that, while he had a little plaque in his arteries, there were no red flags. In retrospect, he said, he knew he didn’t feel right though and what ended happening “was like the perfect storm.”

His genetic predisposition made it more likely he would experience inflammation and build up plaque in his artery. While it’s not uncommon for endurance athletes to build up plaque in the LAD, there are different kinds of placque in the arteries and the kind athletes build up isn’t always problematic. When plaque is calcified it tends to be more dormant and stable, but O’Donnell had built up plaque that could come loose. The increased blood flow of a race then also had a sheering effect on that plaque, making it come loose and causing an abrupt blockage, plus his genetic risk factors for inflammation contributed to causing the artery wall to fail—all leading to an acute cardiac event.

RELATED: What to Look For in Your Own Heart Health

Basically, he said, given what they know now he could have had this heart attack at some point later in his life. The years of being a professional athlete might have contributed to it happening sooner, but at the same time, he said, endurance athletes often develop ancillary vessels around their heart earlier in life than non-athletes. In this case, those ancillary vessels allowed blood to keep pumping when the blockage occurred.

“It might have saved my life too,” he said. “There’s so many factors.”

He’s feeling better now, though there have been some side effects of the medication he’s on and his body has had to adapt to a foreign object, the stent in his artery. He’s also focusing on preventative things to decrease arterial inflammation like leafy greens, managing stress, and gut health. While statins are also an option, he opted not to go that route because of the potential performance side effects.

The things he would have done differently, and that he advises other people to do:

  • Know your family history – O’Donnell only recently found out his family had a long history of coronary disease and his grandfather had died from the same kind of LAD blockage
  • Know the signs of a heart attack – signs of a heart attack include chest discomfort, discomfort in other areas of the upper body, shortness of breath, and breaking out in a cold sweat, nausea or lightheadedness; and trust your body when you feel that something’s wrong!
  • Know your blood work and DNA testing – the types of lipids in your blood and genetic factors can be indicators that can help you manage the risk

“There’s always risk, there’s risk in anything,” he said, but he doesn’t want to scare anyone off of exercise—which is exponentially better for you than not exercising.

And, for O’Donnell personally, after two decades as a pro triathlete, “I want to race to perform and push the boundaries. And if I can’t do that, I’m OK with shifting gears and having a different role in the sport, but luckily I didn’t have to.” Given everything he knows now, he realizes he was incredibly lucky all around.

RELATED: Do Triathletes Need to Worry About Heart Attacks?