Low dose tPA dissolved masses 2 to 3 times faster, dramatically boosting survival
WEDNESDAY, May 14 (HealthDay News) -- Researchers report they have dramatically increased the survival rate for people with strokes caused by bleeding within the brain by fine-tuning the dosage and timing for administering the clot-busting drug tissue plasminogen activator (tPA).
"We've gone from what's usually an 80 percent death rate in patients with this condition to an 80 percent survival rate," study leader Dr. Daniel Hanley, a professor of neurology at the Johns Hopkins University School of Medicine, said in a prepared statement.
This new treatment protocol for intracerebral hemorrhage (ICH) was developed through a multi-center study and reported this week at the European Stroke Conference, in Nice, France.
ICH causes blood to clot inside the brain's interior cavities, building up pressure within the brain. The higher pressure, along with inflammation caused by chemicals in the trapped blood, can irreversibly damage the brain, usually leading to death or extreme disability. No treatment existed for this until recently, Hanley said.
High doses (80 milligrams to 100 milligrams) of tPA have proven effective at breaking up clots in conditions such as heart attacks and other types of strokes, but there was concern that such levels of the drug may cause excessive bleeding in ICH patients. Previous studies showed that giving tPA to ICH patients hadn't significantly increased bleeding or death, so Hanley and his colleagues tested low doses to try to find the safest and most effective treatment regimen possible.
The researchers recruited 52 patients from across the United States, Canada, Great Britain and Germany who were recently diagnosed with ICH. Using the same catheter the patients had received inside the brain to release the trapped blood (the usual treatment for ICH), the researchers flooded tPA directly onto the clot in varying amounts.
The clots dissolved within three to four days on average -- two to three times faster than those of previous patients who didn't receive tPA. The clots of patients receiving 1 milligram of tPA every eight hours dissolved about a day faster than those on lower dose tPA regimens. Additional bleeding was minimal, regardless of what level dose the patients received.
More than 80 percent of the patients were alive one month after treatment. Ten percent of these patients had also recovered enough to return to their jobs, the researchers reported.
"We think that this treatment is the most promising story in brain hemorrhage in many years," Hanley said. "We've taken a condition that used to have an extremely high rate of death and disability and turned it around."
A definitive trial to test this treatment in 500 patients is now being planned by the researchers.
The U.S. Centers for Disease Control and Prevention has more about how to prevent strokes.
-- Kevin McKeever
SOURCE: John Hopkins University, news release, May 14, 2008
All rights reserved