With the publication of two more studies Friday about debilitating ­ischemic strokes, Medtronic PLC is pushing for new medical guidelines that would recommend doctors physically remove brain clots in many cases rather than just treating them with drugs or medical therapy.

On Friday, the New England Journal of Medicine published two papers supported by Ireland-based Medtronic that found patients whose blood clots were quickly removed from arteries in the brain returned to "functional independence" without neurological disabilities much more often than patients in a control group without clot-removal.

A stroke happens when blood supply is cut off in part of the brain, killing brain cells and often causing neurological disabilities and death. It's the fifth-leading cause of death in the United States and costs the country an estimated $54 billion a year. ­Ischemic stroke is when the blood flow is interrupted by a blood clot.

The seven-country Swift Prime trial published ­Friday reported 60 percent of patients with acute ischemic stroke returned to functional independence when Medtronic's Solitaire clot-removal device was used in addition to standard therapy. That compares with 36 percent in the randomized control group. The second study, called Revascat, evaluated most of the stroke patients in a given region — Catalonia, Spain — and found 44 percent returned to functional independence after being treated with the Solitaire within eight hours of having stroke symptoms, compared with 28 percent in the control group. Medtronic provided financial support for both studies.

Those studies follow publication of three others in the New England Journal of Medicine that documented similar support for doing a stent thrombectomy procedure in addition to giving standard ­ treatments.

"These findings are bringing the global stroke treatment community together to rethink how we provide stroke care," Brett Wall, president of Medtronic's neurovascular business, said in a statement. "We support the revision of guidelines and the benefit that this will drive to patients, health systems and our broader society."

Dr. Bharathi Jagadeesan, who treated stroke patients at Hennepin County Medical Center as part of the Swift Prime trial, said Medtronic's device puts another tool in doctors' hands for fighting the effects of ischemic stroke.

"Clot-busting medication is still our first-line therapy. However, it must be administered within 4.5 hours of the onset of stroke symptoms and is not safe in patients with a significant bleeding risk," Jagadeesan said in a statement.

The Solitaire is a small, metal mesh stent on the end of a long catheter that is inserted through an incision in the leg and fed into the blocked arteries in the brain, where it can grab and remove the clot.

No matter what therapy is used, physicians say people who show signs of stroke should get to a hospital as soon as they can because the effectiveness of therapies wanes with time. Signs include a droop on one side of the face, weakness or numbness in one arm and slurred speech.

Joe Carlson • 612-673-4779

Twitter: @_JoeCarlson