Allan Nascimento, the Brazilian mixed martial artist who competed in the UFC flyweight division, has died after what the promotion described as “an apparent heart attack in his sleep,” the organization shared Monday on social media.
Nascimento was 34. He had most recently stepped into the Octagon at a UFC event in June.
“This morning, Monday, August 3rd, our beloved flyweight fighter, Allan Nascimento, was found unresponsive after suffering an apparent heart attack in his sleep,” the UFC wrote in an Instagram caption Monday. “Despite the efforts of the responding medical team, he was pronounced deceased at the scene.”
The UFC also extended sympathy to those closest to the fighter, adding, “Our thoughts and deepest condolences are with Allan’s family, friends, teammates, and loved ones during this incredibly difficult time.”
According to ESPN, Nascimento built a professional MMA record of 22 victories and 7 defeats after beginning his career in 2011.
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During his UFC run, Nascimento went 4-2 across six fights. His final appearance came on June 20, when he lost a split decision to Mitch Raposo, according to his official UFC fighter profile.
Before that setback, Nascimento had been on a strong stretch inside the promotion, winning four of his previous five UFC bouts dating back to May 2022.
In an Instagram video posted June 8, Nascimento reflected on the roots of his combat sports journey, saying he first began training and competing in Muay Thai in 2007.
“I was a skinny, tiny guy, and when I entered the gym … they had already nicknamed me Puro Osso,” he said in the video, referencing the Portuguese idiom for “skin and bones.” “At the time, my parents were totally against it … [but] little by little, they really adapted — they liked it. And good that it worked, right?”
A heart attack, also known as a myocardial infarction, occurs when blood flow is blocked to a part of the heart muscle, preventing it from getting enough oxygen, according to the National Heart, Lung, and Blood Institute. If blood flow is not restored quickly, the agency states, the heart muscle begins to die.
“Most heart attacks are caused by coronary artery disease,” the agency states. “Your age, lifestyle habits, and other medical conditions can raise your risk of a heart attack.”
Symptoms of a heart attack can include chest and upper body pain, shortness of breath, dizziness, sweatiness, and nausea, although women frequently experience different symptoms, the NHLBI says.
Heart attacks incredibly common. According to the Centers for Disease Control and Prevention, about 805,000 people in the U.S. have a heart attack each year, with one heart attack occurring every 40 seconds.
“If you think you or someone else may be having a heart attack, call 9-1-1 right away. Acting fast can save your life,” the NHLBI states. “The longer the heart goes without enough oxygen, the more damage is done to the heart muscle.”
According to the agency, many people who have heart attacks survive and go on to lead full, active lives.
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