ASA: Intracranial Thrombolytics Prompt Dramatic Stroke Response

SAN FRANCISCO, Feb. 12 -- A quarter of stroke patients given the thrombolytic Activase (tPA, Alteplase) in a six-hour intra-arterial window, twice the FDA-approved intravenous window, had a seemingly miraculous recovery within 24 hours, researchers said here.

Patients with such an excellent response were more likely to have had earlier treatment (mean 198 minutes versus 299 minutes) and more open blood vessels feeding the area of the brain affected by ischemia, said Gregory A. Christoforidis, M.D., of Ohio State University in Columbus, at the American Stroke Association meeting.

Some patients have an immediate response, Dr. Christoforidis said, moving limbs on the affected side of the body -- even on the table while the clot is dissolving, "Sometimes it's fairly dramatic he said."

He cited a patient who responded who had come in comatose five and a half hours after onset of a basal artery thrombosis. "One of his friends came in and sprinkled holy water on him," Dr. Christoforidis said.

But the patient woke up as soon as the anesthetic wore off and suffered only double vision thereafter. The saving grace for this patient may have been his good pial collaterals, the angiographic indicator of the number of ancillary blood vessels feeding the affected area," Dr. Christoforidis added.

To determine what factors were most predictive of the so-called Lazarus phenomenon, the researchers retrospectively examined clinical information, CT scans, and arteriograms from 108 consecutive patients who underwent intra-arterial thrombolysis within six hours of symptom onset at their institution.

For basal artery occlusions, the window is considered even longer. In the study, these patients were treated up to 24 hours after symptom onset.

A Lazarus-type response was defined as at least a 50% decrease in National Institutes of Health Stroke Scale severity score in the 24 hours after treatment. Pial collaterals were determined from angiography.

Patients were an average 68 years old (range 18 to 90). Most were given tPA (78) while 27 received Abbokinase (urokinase) and three received pro-urokinase. Most patients had a middle cerebral arterial stroke (80) while 17 had an internal carotid arterial stroke, four had an anterior cerebral arterial stroke, and seven had a basilar or vertebral arterial stroke.

The only significant factors among the 26 patients (24.1%) who had the Lazarus phenomenon compared with the 82 who did not were time to treatment and pial collaterals. The findings were:

• Average time to treatment was 198 minutes among Lazarus-response patients and 299 minutes among other patients (P=0.0002), and
• Good pial collateral formation was present among 92.3% of Lazarus-response patients versus 59.7% of other patients (P=0.0022).

The effect was seen among 50% of patients who had both good collaterals and were treated within 270 minutes (4.5 hours) but among only about 20% of those who had good collaterals but were treated later.

This shows that patients with good collaterals will do even better if they are recanalized, Dr. Christoforidis said

"Some think, 'Oh, he has good pial collaterals, we don't have to do anything,'" he said. "No! No, use them."