Combined local and systemic thrombolysis may boost recanalization

7 July 2008

MedWire News: Undergoing endovascular therapy simultaneously with intravenous thrombolysis may improve stroke patients' chances of recanalizing and having a good functional outcome, results of a small trial suggest.

"Some pilot studies have demonstrated that the combination of intravenous (iv) recombinant tissue plasminogen activator (rtPA) and endovascular therapy is feasible and safe," say Shiro Sugiura (Osaka Neurological Institute, Japan) and team.

They note, however, that most of these studies investigated intra-arterial therapy only as a rescue therapy after the failure of iv thrombolysis.

"We thought that waiting until certifying whether recanalization by iv rtPA was successful or not might waste precious time for rescuing ischemic penumbra," the researchers write in the American Journal of Neuroradiology.

Sixteen patients with middle cerebral artery occlusions eligible for thrombolysis were identified as endovascular therapy candidates, and gave informed consent. These patients received 0.6 mg/kg rtPA with simultaneous endovascular therapy consisting of local administration of rtPA to a maximum of 10 mg. If unsuccessful, this was followed by balloon angioplasty.

This approach resulted in 88% of patients achieving recanalization, reflected by an 11-point improvement in National Institutes of Health Stroke Scale (NIHSS) scores within 24 hours of admission.

Thirteen patients were treated with iv rtPA (0.6 mg/kg) alone. Recanalization was not directly assessed in this group, but the average NIHSS improvement was just 5 points.

At 90 days, 63% of patients in the combined therapy group achieved a good functional outcome, defined as a modified Rankin Scale score of 0-1, compared with just 15% of patients in the rtPA only group.

Just one patient - in the rtPA only group - suffered symptomatic intracranial hemorrhage. One patient in the combined therapy group and no patients in the rtPA only group had asymptomatic hemorrhage.

The researchers propose several possible explanations for the low hemorrhage rate, including pre-intervention treatment with a free radical scavenger, which is approved in Japan.

"Although additional randomized studies are needed to confirm these results, aggressive combined therapy as the first choice of treatment may lead to a favorable clinical outcome for patients with hyperacute major arterial occlusion," the team concludes.

Am J Neuroradiol 2008; 29: 1061-1066