The US Senator remained in hospital on Thursday night a day after he was admitted feeling lightheaded, per BBC.
Mr Fetterman began feeling lightheaded while attending a Democratic retreat and was taken to George Washington University Hospital on Wednesday night.
Sworn into office last month, he had a stroke in May and was in recovery for much of his election campaign.
Mr Fetterman’s victory handed Democrats a wafer-thin majority in the upper chamber of Congress.
His communications director, Joe Calvello, released a statement on Thursday evening saying the senator had just received the results of an MRI scan, which together with the other hospital tests ruled out a new stroke, according to BBC.
In May, Mr Fetterman easily won the Democratic nomination for the open US Senate seat in Pennsylvania four days after suffering the stroke.
He is said to have endured a nearly three-hour surgery on the day he won the primary contest, and spent a total of nine days in hospital.
According to a statement issued by his doctor, the 53-year-old’s stroke was caused by atrial fibrillation, or an irregular heart rhythm.
He also suffers from cardiomyopathy, a disease that makes it harder for the heart to pump blood to the rest of the body and can cause heart failure. He was fitted with a pacemaker and defibrillator.
Mr Fetterman returned to the campaign trail in August with significant speech impairments, and his health became a focus of an increasingly tight race.
But the Democrat comfortably defeated his Republican opponent – Mehmet Oz, better known as the celebrity surgeon Dr Oz – in November’s general election.