Intra-Arterial Clot-Dissolving Therapy Improves Results of Early Stroke Treatment

Newswise — For patients with stroke treated within three hours, giving "clot-busting" drugs through the arteries—instead of the veins—may improve the chances of good outcomes, suggests a study in the January issue of Neurosurgery.

Led by Dr. Eric C. Bourekas of The Ohio State University, Columbus, the researchers analyzed the results of early intra-arterial (IA) thrombolytic (clot-dissolving) treatment in 36 patients with stroke. All patients were treated within three hours after the first symptoms of stroke caused by a blood clot obstructing flow to the brain.

Intra-arterial thrombolytic therapy improved flow in the blocked blood vessel in 75 percent of patients. In 39 percent, flow was restored completely. These "recanalization rates" were about twice as high as in studies of patients receiving thrombolytic drugs through the standard intravenous (IV) route.

More importantly, IA thrombolytic therapy seemed to improve the final outcomes of treatment. One to three months after IA treatment, 50 percent of patients had little or no disability resulting from their stroke. This compared with a 39 percent rate for patients in a landmark National Institute of Neurological Disorders and Stroke (NINDS) study of early IV thrombolytic therapy.

Intra-arterial thrombolytic therapy had an eleven percent rate of bleeding problems, an important risk of clot-dissolving drug treatment. This was slightly higher than in the NINDS study. The risk of death in patients receiving IA therapy was 22 percent, similar to that with IV therapy.

Thrombolytic therapy offers the best chance of good recovery from stroke, but the "clot-busting" drugs must be given within a few hours after the first symptoms. For the patients in the new study, average time to treatment was 1 hour, 46 minutes. They represented just 18 percent of all stroke patients treated over the nine-year study period.

Although the study is not a direct comparison of IA vs IV thrombolytic therapy, the results suggest that early IA treatment improves the chances of disability-free outcomes in patients with stroke. This probably reflects the higher success rate in reopening the blocked artery, achieved by delivering a higher concentration of the clot-dissolving drug directly to the area of blockage.

Dr. Bourekas and colleagues call for more research to compare the results of IA vs IV thrombolytic therapy. However, because IA treatment is more invasive, they emphasize that it should only be performed at hospitals with specialized stroke teams available around the clock.

"Intraarterial Thrombolytic Therapy Within 3 Hours of the Onset of Stroke" by Eric Borekas, M.D., et.al., NeurosurgeryVol. 54, No. 1, Pg.39January 2004