Acetaminophen: For Fevers, Pains, ... and Stroke?
When people suffer a severe stroke or arrive at the hospital too late to qualify for the clot-buster tPA, the only FDA-approved treatment for stroke, doctors have little to offer them.
However, by using a modified form of tPA called reteplase and by delivering it directly into the clogged artery that triggered the stroke, rather than indirectly through the veins, researchers hope to break through the clot and restore blood flow to brains already damaged by the stroke.
In 16 patients given this treatment, as reported in the July issue of Neurosurgery, 14 eventually had good return of blood flow through the clogged artery, including seven who needed additional surgery to help break up the clot. But, overall, only seven had neurological improvement. The other nine died, most from massive stroke.
The high death rate and poor outcome probably resulted from the initial severity of stroke in these patients, Alexandrov explains.
In any case, more than half of people treated with tPA into the veins have severe disability or die due to the stroke, according to the study's lead author Adrian I. Qureshi, MD, an assistant professor of neurosurgery and co-director of the Toshiba Stroke Research Center in Buffalo, N.Y.
But this option is not for all stroke patients. Because of the high risks involved in injecting reteplase through the clogged artery, Qureshi recommends considering it only for those patients who are ineligible for tPA.
"Reopening of the blood vessel did not necessarily translate into improved outcome," Goldstein says. "The approach remains experimental and the risks vs. benefits need to be defined."
In patients with persistent clots even after tPA is injected in the veins, "the continuing clot presence in brain [vessels] leads to poor outcomes," including severe disability and death, Alexandrov says. "In this light, studies of ... new clot-busting agents appear timely and important."