Anti-clot drug not 100% efffective

The clot-busting drug t-PA, used for years to halt heart attacks, proved ineffective when given during cardiac arrests in which patients had no pulse, according to a study in New England Journal of Medicine. "We found no evidence that the administration of t-PA during CPR improved the likelihood of either survival to hospital discharge or a return of spontaneous circulation," researchers concluded.

The findings do not apply to t-PA`s use in other types of heart attacks, where its effectiveness is well documented.

Also known by the brand name Activase, t-PA dissolves clots that block the flow of blood to the heart muscle.

Out-of-hospital cardiac arrest results in some 250,000 deaths annually in the United States and Canada. Bureau Report