'Third time lucky' - Olympic swim champ Chalmers has heart surgery again

Australian Olympic 100m freestyle champion Kyle Chalmers was recovering Thursday after a third operation to treat a long-term heart condition.

The 21-year-old, who claimed silver at last month's world championships in South Korea, posted a photo on Instagram of himself in a hospital bed giving the thumbs up and saying "third time lucky".

Chalmers said he was hopeful the problem has now been fixed "once and for all" as the clock ticks down to next year's Tokyo Olympics.

The Rio 2016 gold medallist underwent surgery on the same condition in June 2017, forcing him to pull out of that year's world championships.

A previous operation had not helped the problem known as supraventricular tachycardia, which occasionally causes his heart to race.

Australia's head swim coach Jacco Verhaeren said Chalmers had no problems during the recent world championships, but there were some concerns during his preparations.

"Everything with your heart sounds like a big deal but in this case, it's a very targeted procedure," he told the Sydney Morning Herald.

"He's had it done before but it didn't get the result that had hoped for and they knew exactly what to target now.

"They thought it was best to do it now before the (Tokyo) Olympic season kicks off," he added.

Several high-profile swimmers wished him well, including top rival Caeleb Dressel, who swam the second-fastest 100m freestyle in history to retain his world title last month, narrowly ahead of Chalmers.

"You'll be back quick my boy. All the best," the American said on Instagram, while Britain's 100m breaststroke world champion Adam Peaty added: "All the best brother.