Early thrombolysis benefits moderate and mild stroke patients



Early intravenous thrombolysis appears to benefit patients with moderate stroke as well as those with mild stroke, although it’s not completely clear if the benefit in mild patients is due more to the lower baseline stroke severity.

Nevertheless, patients with mild or moderate symptoms should get thrombolytic treatment as early as possible – within 90 minutes of symptom onset and even earlier, if possible, Dr. Daniel Strbian and his colleagues reported in the Aug. 22 issue of Stroke (doi: 10.1161/STROKEAHA.111.000819).

Those with mild symptoms and early treatment were 51% more likely to have excellent 3-month outcomes, defined as a modified Rankin Scale (mRS) score of 0, in a secondary analysis of the study, reported Dr. Strbian of Helsinki University Central Hospital, Finland, and his coauthors.

The study builds on the authors’ previous single-center analysis of ultra-early thrombolytic treatment delivered within 70 minutes of symptom onset, which found significantly improved 3-month outcomes in patients with severe stroke. But, they noted, "because not all patients benefit from early IV thrombolysis equally ... we aimed to explore, in a large multicenter dataset, whether the extra benefit is distributed equally among predefined stroke severity subgroups of acute ischemic stroke patients."

However, only 6% of the 878 patients in that cohort got the ultra-early treatment. Therefore, the new analysis was expanded to examine outcomes in patients treated within 90 minutes. "This is a relevant time-point, because the number needed to treat doubles from 4.5 to 9 for patients with [treatment initiation of] 91-180 minutes, compared with ... 90 minutes or less."

The multicenter analysis comprised 6,856 patients treated at four stroke centers; 19% of these received treatment within 90 minutes of symptom onset.

Patients had a mean age of 72 years. The mean baseline National Institutes of Health Stroke Score (NIHSS) was 11; the score was mild in one-third of patients, moderate in one-third, and severe in one-third.

Compared with later treatment, treatment within 90 minutes or less for patients with moderate symptoms was significantly associated with excellent 3-month outcomes, defined as an mRS score of 0-1 (odds ratio, 1.37). This benefit was not seen in patients with severe symptoms (OR, 1.00), or in those with mild symptoms (OR, 1.04).

However, the authors noted, the lack of benefit for patients with mild symptoms may have been influenced by their less severe pathophysiology at baseline. To offset this possibility they conducted a subanalysis, restricting 3-month outcomes to the best possible measurement – an mRS of 0. Patients who got the early treatment were 51% more likely to achieve this outcome than were those treated outside the 90-minute window (OR, 1.51).

The early treatment was also associated with a significantly lower proportion of any intracranial hemorrhage (14.8% vs. 17.6%), and a nonsignificantly lower proportion of symptomatic intracranial hemorrhage (3.7% vs. 4.5%).

Early treatment was not associated with mortality – a finding contrary to the authors’ prior study. "This may be because of the limited number of patients treated ultra-early in the current cohort," they said.

Dr. Strbian reported no financial disclosures. However, 10 of the 19 coauthors did report multiple relationships with pharmaceutical companies.

On Twitter @Alz_Gal

Recommended Reading

Stroke outcomes poorer when criteria precluded endovascular therapy
MDedge Cardiology
Early surgery for intracerebral bleeds may benefit a select few
MDedge Cardiology
Stenting, then heart surgery best approach for carotid, coronary disease
MDedge Cardiology
Edwards to start U.S. trial of SAPIEN 3
MDedge Cardiology
Laser extraction damages remaining leads
MDedge Cardiology
Baseline PR interval predicts response to biventricular CRT
MDedge Cardiology
Best CRT outcomes with LBBB and prolonged QRS
MDedge Cardiology
Early surgery vs. watchful waiting for flail mitral leaflets
MDedge Cardiology
CABG mortality goal elusive without process improvements
MDedge Cardiology
Bivalirudin linked to less bleeding, but more severe complications, vs. eptifibatide
MDedge Cardiology