Concomitant use of antiplatelet agents with tissue plasminogen activator during stroke thrombolysis.

Abstract

P237 Background: In the setting of acute myocardial infarction, aspirin has a significant benefit on mortality when combined with a thrombolytic. The NINDS guidelines recommend witholding antiplatelet agents (APA) for 24 hours after tPA administration for acute stroke. Post hoc analysis of the NINDS tPA study did not show worse outcomes in patients using APA prior to treatment, even though APA have a long platelet-inhibitory effect (the life of the platelet). Objective: To determine whether concomitant APA and tPA use was associated with worse outcomes. Method: We compared demographics, vascular risk factors, hemorrhagic complications, and 3 month outcomes of patients on APA at the time of their stroke with those patients not taking APA, in our prospective registry of tPA-treated patients. Results: Between 1 December 1998 and 24 July 2000, 64 patients were treated with tPA; 3 month follow-up data are available on 47 (73%). At the time of their stroke, 24 (38%) were taking APA, 40 (62%) were not. Patients taking APA were more likely to have a history of coronary heart disease, previous stroke and previous TIA, and they had higher baseline modified Rankin Scores (mRS). There was a trend for them to be older (75.3 years [APA] vs. 70.2 years [no APA], p =0.06). There was no increase in major intracranial or systemic hemorrhages at 36 hours (0% [APA] vs. 5% [no APA], p =0.54), or in mortality at 3 months (13% [APA] vs. 15% [no APA], p =1.00). More patients taking an APA had a NIH Stroke Scale score (NIHSSS) of 0–1, but this did not reach statistical significance (40% [APA] vs. 29% [no APA], p =0.42). There was a non-significant trend for fewer patients on an APA to have a 3 month mRS of 0–1 (20% [APA] vs. 41% [no APA], p =0.17). However, given their higher baseline mRS, we also looked at the percentage who returned to their baseline mRS, this favored the APA group but again it did not reach statistically significance (40% [APA] vs. 28% [no APA], p =0.38). Conclusion: Concomitant APA and tPA use appears safe and may be associated with an improved outcome. The potential beneficial effect of the combination merits further study.