Inside job dissolves blood clot pronto

From San Francisco, at the International Stroke Conference

An experimental procedure that delivers a clot-busting drug directly to the brain can bring on a remarkable turnaround in some stroke patients, researchers find.

“Some people improve even while they’re on the [operating] table as we dissolve the clot,” says radiologist Gregory Christoforidis of the Ohio State University College of Medicine in Columbus. For example, a patient might regain control over a side of his or her body that had been affected by the stroke and begin moving an arm or leg, he says.

In the procedure, a catheter tipped with a dose of the drug tissue plasminogen activator is threaded through arteries from the groin up to the site of the clot. There, the catheter releases the drug onto the blockage, a more direct approach than giving a patient intravenous drugs that flow throughout the body, says Christoforidis. The targeted approach also limits the risk of hemorrhage elsewhere in the body, he says.

Of 102 stroke patients given the intra-arterial clot buster, 25 showed dramatic improvement over the course of 24 hours. All had had stroke symptoms for up to 6 hours at the times of their procedures. Standard clot busters are usually effective only up to 3 hours after symptoms start (SN: 1/18/03, p. 37: http://sciencenews.org/articles/20030118/fob5.asp).

The dramatic turnaround was more likely in patients who received the treatment within 3 hours and who had an array of alternative blood vessels that could supply brain tissue downstream from the clot.

Although the study measured the effects of the intraartery procedure done within 6 hours of stroke onset, other researchers are trying the approach on patients who have had symptoms for 12 to 24 hours.