The seven-foot, 255-pound Dutch heavyweight was sidelined in 2013 when he was diagnosed with a rare heart condition. Finally cleared by doctors, he was scratched from UFC 175 in July when he blacked out in the dressing room on the eve of entering the cage.
After a change in medication, Struve (29-6) is back to face former Strikeforce champion Alistair Overeem (37-14 with one no contest) on a televised UFC Fight Night card Saturday in Phoenix.
He says the difference is night and day.
"It's great to be back, enjoying fight week and just having a lot of fun," Struve said in an interview. "Looking back at how I felt the last time, being on the medication I was on ... feeling horrible and just not happy at all."
The main card at US Airways Center on Saturday features two other heavyweight bouts.
Former champion Junior Dos Santos, currently ranked second among heavyweight contenders, takes on No. 4 Stipe Miocic in the main event. Matt Mitrione, ranked 14th, meets No. 12 Gabriel Gonzaga.
Lightweight Nate Diaz, ranked 14th among 155-pound contenders, returns to action to face No. 3 Rafael Dos Anjos in the co-main event.
After suffering a broken jaw in a knockout loss to hard-hitting Mark Hunt in Japan in March 2013, Struve was diagnosed with a leaking aortic valve, as well an enlarged heart. It meant that his heart was only pumping 60 per cent of his blood into the aorta and then the rest of his body. The remaining 40 per cent was ending up back in the heart chamber.
Struve had been sick for six weeks before the Hunt bout and things didn't get better afterwards. He couldn't sleep and had no energy. Then one day at his parents' house, he got dizzy standing up after working at the computer. He sat down and blacked out briefly.
A trip to hospital and subsequent barrage of tests eventually found the heart problem. But he says he underestimated the side effects of the medication.
"I didn't think two little pills a day would do anything weird to me," he said.
When his body began to act up backstage at UFC 175, the first thing Struve thought of was his heart — which only exacerbated the problem. He had also been dealing with the death of his father after a long illness.
It all made for a bad cocktail of emotions.
"My heart just went crazy," he said. "I lost control of my breathing. It was just a really really bad experience. All the negative things became a lot more negative because of the medication. I wasn't able to control that."
The aftermath was captured on UFC president Dana White's video blog. Struve is shown weeping in the bathroom as his opponent, Mitrione, tries to console him.
"Don't worry," Mitrione says as Struve repeatedly apologizes. "The ticker will get back to normal and we'll get this rescheduled."
Struve thought his career was over. Fortunately answers were quick to come.
One of his trainers ran into someone at their hotel in Las Vegas who said he had experienced side effects from the same heart medication. Struve heard a similar story from someone else a few days later.
"I had something to grasp onto it," he said.
His doctor put him on another drug, which seems to be doing the trick. Struve says he will probably have to undergo surgery at some point but hopes to do it after his fighting career.
The 26-year-old Struve now just wants to get his focus back on fighting. Prior to the loss to Hunt, he had reeled off wins over Miocic, Lavar Johnson, Dave Herman and Pat Barry.
These days Struve is looking for as many answers as he can find. He has been working with some "mental experts" to help deal with the stress of fighting for a living.
His height and reach are powerful weapons, as is his set of submission skills. He is also durable although he has suffered punishing knockouts losses at the hands of Junior Dos Santos, Roy (Big Country) Nelson, Travis Browne and Hunt.
At six foot four and 265 pounds, the 34-year-old Overeem is like a rhino in the cage. But he has lost three of his last four with opponents surviving early attacks to put the big man away.
"He's not the same fighter he used to be a couple of years ago, in my opinion," Struve said. "I cannot wait to show that I'm just a couple of levels above him."
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