Sen. Bernie Sanders abruptly suspended his 2020 White House bid on Wednesday after undergoing an unexpected heart procedure — with the 78-year-old’s campaign saying he will be sidelined “until further notice.”

The Vermont senator was rushed to a Las Vegas hospital Tuesday night after suffering what his campaign characterized as “some chest discomfort” at a Nevada event.

“Following medical evaluation and testing he was found to have a blockage in one artery and two stents were successfully inserted,” noted Team Sanders.

The irascible democratic socialist was said to be recuperating in good cheer, and his wife, Jane O’Meara Sanders, told The Associated Press that Sanders was “doing really well.”

Sanders recently had to scrap some South Carolina stump stops after losing his voice, but his campaign insisted he was fine, and manager Faiz Shakir didn’t mention any health woes during a Tuesday night phone call with supporters.

During the 2016 election cycle, Sanders’ doctor noted that he had a history of mildly elevated cholesterol, but was otherwise in good health.

The scare kept Sanders from a 2020 Gun Safety Forum in Sin City, and came just hours after his campaign boasted of the $25.3 million war chest it had amassed over the past three months.

It also comes as Sanders, who’s been solidly third in Democratic polling for some time, is trying to gain ground on front-running former vice president Joe Biden and hard-charging Massachusetts Sen. Elizabeth Warren.

“You are constantly moving,” said Peter Loge, an associate professor of media and public affairs at George Washington University, explaining the constant stress of running a nation-spanning campaign.

“They don’t spend a lot of time sitting down or standing still,” said Loge, who worked on former California Gov. Jerry Brown’s 1992 White House bid. “And while you’re in this constant motion, you’re also not eating.”

It remains unclear exactly how long Sanders will be on the shelf, but he’s scheduled to take the stage in Ohio on Oct. 15 for the fourth Democratic primary debate.

Some of Sanders’ opponents in that crowded field wished him well on Wednesday.

“@DrBiden and I are sending our best wishes to @BernieSanders, Jane, and the whole Sanders family,” tweeted Joe Biden. “Anyone who knows Bernie understands what a force he is.”

Added Warren, “Bruce, Team Warren, and I are sending all our best wishes for a speedy recovery to @Bernie Sanders. I hope to see my friend back on the campaign trail very soon.”

At 76 and 70, respectively, Biden and Warren are no spring chickens, but Sanders is the oldest candidate among the 2020 field and would easily be the oldest president to take office were he to win.

Hillary Clinton, now 71, had her own health scares in the 2016 race, when she had to take time off to battle pneumonia and fainted at a 9/11 memorial event. With Wires