DAUPHIN COUNTY, Pa. (WHTM) — Dr. Raymond Reichwein, Penn State Health Stroke Neurologist and Co-Director of its comprehensive stroke center talked to abc27 about the main symptoms of a stroke.

The same type of stroke Lieutenant Governor and Democratic Senate nominee John Fetterman, suffered Friday.

“The first is sudden onset neurological symptoms one minute you’re normal, next minute your suddenly not normal,” said Dr. Reichwein.

Dr. Reichwein tells abc27 his team sees around seven to 800 of that same type of stroke each year, which starts with an irregular heart rhythm.

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He says by going in and out of it, a clot can form in the upper chamber of your heart.

To be clear, Dr. Reichwein is not treating Fetterman nor has he seen or spoken to his treating doctors but he was able to offer insight into how these strokes occur.

Fetterman had a pacemaker installed to regulate his heart rhythm.

“Many people don’t know they are in that rhythm so you can be completely asymptomatic,” said Reichwein.

While that won’t prevent another stroke, it is a layer of protection on top of other treatments. Dr. Reichwein says very often patients end up with little or no serious repercussions down the line.

Fetterman will resume his duties as Lt. Governor of Pennsylvania on May 23.