The bottom line, according to Wahlgren: "if patient treatment has been delayed, it is still safe to treat a patient beyond the time limit of three hours."
The results were expected to be presented at an international meeting in Stockholm in November, "when we will recommend a change in the guidelines," Wahlgren said. "I expect it would be accepted by the international community, both in the United States and Europe, and in the rest of the world."
But the new results do not necessarily mean an end to the three-hour limit, cautioned Dr. Larry Goldstein, professor of neurology at Duke University and director of the Duke Stroke Center in Durham, N.C.
"They are consistent with a combined analysis done some time ago that suggested we might be able to treat beyond three hours," Goldstein said. "But those were observational studies, as was this one. Controlled trials done to test that belief have not shown benefit."
It will take a change in the current guidelines to alter the three-hour limit, he said, and the overall benefit of tPA is greater when it is given earlier. "The sooner you get blood to the brain, the better," Goldstein said.
There's more on tPA at the American Heart Association.
SOURCES: Nils Walhgren, M.D., professor, neurology, Karolinska Institute, Stockholm, Sweden; Larry Goldstein, M.D., professor of neurology, Duke University, Durham, N.C.; Sept. 14, 2008, The Lancet online
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