Blood Clot Removal Boosts Stroke Risk in Heart Attack Patients

A common practice that involves using a syringe to remove a patient's blood clots during treatment for a heart attack has been found to increase the risk of stroke, researchers said Monday.

The study led by McMaster University and the University of Toronto is the largest of its kind to date. 

It was presented at the American College of Cardiology annual conference in San Diego and published simultaneously in the New England Journal of Medicine.

More than 10,000 patients in 20 countries were part of the randomized controlled trial.

Some heart attack patients had just an angioplasty, or percutaneous coronary intervention, which opens a blocked artery in the heart using a balloon.

Others had an angioplasty plus a manual thrombectomy, in which a cardiologist uses a syringe attached to a tube to create suction to remove the clot from the artery, the researchers said.

The result found "no benefit from the routine use of thrombectomy, or blood clot removal, and that heart attack patients receiving this were more likely to have a stroke," according to the study.

Since current guidelines leave it up to individual doctors to decide whether or not to do the syringe procedure, study authors said they hope their study will lead to changes in practice.

"The message from this study is that thrombectomy should not be used as a routine strategy," said lead author Sanjit Jolly, an associate professor of medicine of McMaster's Michael G. DeGroote School of Medicine. 

"This is still an important therapy, but given the downsides we observed in our trial, its use should be quite selective and as a measure when an initial balloon angioplasty attempt fails to open up the artery, rather than as a routine strategy."