One night after attending the State of the Union address with other members of Congress, Sen. John Fetterman, D-Pa., spent last night in the hospital. His office says Fetterman reported feeling lightheaded on Wednesday, and was kept overnight for observation.

The senator is in good spirits and has been talking with his staff and family, his office said.

Fetterman was at a Senate Democratic retreat when he started feeling unwell, his communications director, Joe Calvello, said in a statement to journalists. That retreat was reportedly held at the Library of Congress.

"He left and called his staff, who picked him up and drove him to the George Washington University Hospital," Calvello said.

Fetterman's health has been a running undercurrent to his rise to the Senate. He suffered a stroke last year, just before winning his primary race. That prompted the implantation of a pacemaker and defibrillator, and Fetterman said he had previously been diagnosed with atrial fibrillation — an irregular heart rhythm that can cause blood-flow issues.

"Initial tests did not show evidence of a new stroke," Calvello said, but doctors wanted to run more tests and keep the senator in their care overnight.

On Thursday evening, Calvello said the results of an MRI and other tests ruled out a new stroke. He added that Fetterman is also being monitored for seizures.

News of Fetterman's latest hospital stay comes days after he joined President Biden and other Democrats at the Democratic National Committee's winter meeting in Philadelphia.

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