"They [doctors] will go in and clear blockage, fix damage and put a stent where it is needed", Thomas told TMZ.
Kensington Palace did not confirm that Thomas would be missing the wedding, but issued a statement asking for understanding.
Today's biggest royal wedding update-aside from the ongoing saga with Meghan Markle's dad, of course-comes straight from the palace, which officially confirmed the entourage of 10 page boys and bridesmaids who will be leading the way for Markle as she heads down the aisle on May 19.
Kensington Palace could not immediately be reached for comment on Tuesday.
The decision comes after it emerged that he had used a picture agency to set up images of him working out and reading books about the United Kingdom in the run-up to the wedding.
"Everyone loves a wedding so I do think it is an global story, but it's even more special in the States since Meghan is one of us", Guthrie tells THR.
He said he now thinks that though the photo shoot was "stupid", it was not bad enough to keep him from her wedding.
Thomas Markle was set to walk Meghan down the aisle during the church ceremony, and Ragland plans to ride to the chapel with her daughter.
Ragland, who has reportedly already arrived in Britain, is expected to spend Friday night with her daughter in a plush hotel before travelling with her by vehicle to Windsor Castle.
This is a deeply personal moment for Ms Markle in the days before her wedding. The movie dramatized the character of Prince Harry and Meghan Markle and showed too much of romance.
If he does not attend, Meghan's mother may walk her down the aisle instead.
Their outfits will be revealed on the day, but they could look something like this.
Her parents have told how the fourth in line to the throne rules the roost, saying she is "very sweet" but also feisty.
"I can no longer tell FakeHarry and FakeMeghan from #harryandmeghan", one viewer tweeted.
"He was really having heart pains and suffered a heart attack", she said.
We've seen him in a cafe reading up on British history, being measured for a suit, hiking with some weights to get in shape and even driving to ex-wife Doria's house to leave some flowers as a peace offering.
Djokovic and Nadal sail into third round in Rome
After the match, Pliskova didn't shake hands with the chair umpire and struck the chair several times with her racquet. Four-time champion Novak Djokovic also advanced, beating Georgian qualifier Nikoloz Basilashvili 6-4, 6-2.