The stroke that Pennsylvania Lt. Gov. John Fetterman had on Friday was caused by a clot from his heart, which was out of rhythm for too long, the U.S. Senate candidate said Sunday in a statement.
That condition, called atrial fibrillation, is a common cause of strokes, but what exactly does it mean?
When the heart beats normally, the left atrium, the top left chamber of the heart, beats smoothly and rhythmically, 70 times a minute, and sends blood to the chamber below, the left ventricle.
"In fibrillation, the atrium's just wiggling, like a bag of worms, and it's not really squeezing," said Mark Victor, a cardiologist with Cardiology Consultants of Philadelphia who is not involved in Fetterman's treatment. "The blood just drains from the atrium to the ventricle literally just by hydraulic force," rather than being pumped.
What's dangerous is when blood in an appendage off the atrium starts to congeal, forming a clot.
"Every so often, that's where the clot sneaks out to the atrium, down into the ventricle, up into the brain," Victor said.
There are two ways to remove a clot, said Erol Veznedaroglu, a cerebrovascular surgeon with Global Neurosciences Institute, a company that treats stroke victims and other patients at numerous hospitals in the Philadelphia region. Veznedaroglu thought it most likely that Fetterman was treated with a clot-busting drug at Lancaster General, given that Fetterman said the signs and symptoms of the stroke were subtle and that doctors told him he was on his way to a full recovery.
That alternative, for large clots that get into an artery in the brain, is to go "in through the groin and put a catheter all the way up to the clot in the clogged artery in the brain" where a stent can be used to capture the clot allowing it to be pulled out, Veznedaroglu said.
After watching the video of Fetterman and his wife, Veznedaroglu said he expected Fetterman to make a full recovery.
Victor, the cardiologist, said typically people in their 50s with atrial fibrillation would not be treated for the condition unless they had other risk factors, such as diabetes, heart failure, kidney disease or hypertension.
"If he had nothing else wrong with him, he just had lone atrial fibrillation ... he wouldn't typically be considered at high risk for a stroke," Victor said, "but that doesn't mean it doesn't happen. It just means it's much rarer than if he were 71."
