Stroke Survival Rates Improve Following Physical Clot Removal
Stroke survival rates improve with a physical clot-removing procedure done for up to 16 hours after a stroke.This finding expands the treatment window well beyond the current six hour recommendation.
Ischemic Stroke: What Is It?
An ischemic stroke happens when blood vessels supplying the brain become blocked. Brain tissue in the area starts dying. Doctors restore blood flow by injecting clot-busting drugs. These drugs are effective if diagnosis is made early. The area surrounding the dying region, known as the penumbra, can be saved if blood flow is quickly restored. Otherwise, dying brain tissue can expand for hours.
Doctors use a method called perfusion imaging to assess the diminished blood flow and size of the penumbra. In previous studies, perfusion imaging identified patients most likely to benefit from drugs and procedures that restore blood flow.
Stroke: Blood Clot Removal Statistics
The physical removal of a blockage, called a thrombectomy, can help up to six hours after a stroke. In this study, Researchers tested whether removing blood clots up to 16 hours after stroke is also effective.
Researchers identified patients who had salvageable brain tissue up to 16 hours after stroke. They randomized 92 participants, aged 59 to 80, to receive thrombectomy plus standard medical therapy and 90 patients to receive medical therapy alone (control).
Three months after treatment, only 14% of patients receiving the clot removal procedure died compared to controls (26%). Also, 45% of patients achieved functional independence compared to 17% of controls. There were no substantial differences in serious side effects between the groups. These results show overwhelming evidence that removing a stroke clot even 16 hours later is not too late to save the patient.
The National Institute of Neurological Disorders and Stroke (NINDS) supported this study. Results appeared on January 24, 2018, in the New England Journal of Medicine.
“These striking results will have an immediate impact and save people from life-long disability or death,” says NINDS Director Dr. Walter Koroshetz. “I really cannot overstate the size of this effect.”
The results were first announced at the International Stroke Conference in January. Based in part on these findings, the American Heart Association and American Stroke Association immediately issued new guidelines for treating ischemic stroke patients.