Tissue plasminogen activators have been used for more than 20 years to break up blood clots and help stroke patients avoid brain damage.
Researchers have now discovered another possible use for the therapy: as a treatment for patients who wake up during their strokes -- an estimated 15 to 30 percent of patients -- and can't say for certain when symptoms started.
Administered by IV, tissue plasminogen activators must be administered within 4.5 hours of a stroke to be effective. Researchers from the American Heart Association gave a presentation at the organization's recent International Stroke Conference on how brain imaging can assist health care providers in determining when a stroke started.
“We’re replacing a human witness with an MRI scan,” Lee Schwamm, director of acute stroke services at Massachusetts General Hospital, said.
Schwamm is also the lead researcher of a study titled MR WITNESS.
The study used as subjects 80 patients who received tPA treatment approximately 11 hours after they were last asymptomatic for stroke. Of those 80 patients, 44 percent had recovered full functionality three months after having the stroke.
“Many people told me they thought this was a very dangerous thing to do,” Schwamm said. “But we’ve shown this can be done safely, and there’s even a suggestion of efficacy.”
Other findings from the study included that smokers were less likely to achieve full recovery.
Schwamm said he would like to lead a U.S.-based randomized study, I-WITNESS, in the near future to assess the accuracy of MRI or CT technology in the early detection of strokes.
“This is the first time we’ve really turned our attention fully to solving this problem,” he said. “We hope five years from now that we’ll have a new treatment for a large number of patients who are currently not eligible for any treatment, even stent retrievers.
If someone thinks they have a symptom of a stroke before going to sleep, don’t go to sleep -- get help then, when it can be treated.”
Brain imaging may pinpoint time of stroke onset