Risks and Benefits Associated with Prestroke Antiplatelet Therapy Among Patients with Acute Ischemic Stroke Treated with Intravenous Tissue Plasminogen Activator

Many patients who present at a hospital with a stroke are already on blood thinners for one reason or another. It is known that intravenous tissue plasminogen activator (tPA) improves the outcomes of ischemic strokes, but the issue is that it also carries the risk for symptomatic intracranial hemorrhage (sICH), which is actually the worst complications that could come from acute ischemic stroke. Another factor is that the blood thinners that these patients are often taking before they have a stroke, which could increase the chances of sICH when the patient is given tPA. The study done by Xian and colleagues aimed to determine if there was a significant increase risk for patients on antiplatelet therapy who received tPA, evaluated the safety of this in groups who would be clinically relevant and investigate the association that exists between being on antiplatelets prior to tPA administration with clinical outcomes in these cases.

This study included patients who had acute ischemic stroke, received intravenous tPA without combination with endovascular treatment, and had been on an anticoagulant regime before the ischemic stroke. The patients were then broken down into groups based on the types of anticoagulant regimes they had been receiving. The endpoints that the study focused on included sICH, in hospital mortality, discharge ambulatory status and the modified Rankin Scale score that ranges from 0 (no symptoms) to 6 (death). Secondary endpoints included were life-threatening or serious systemic hemorrhage within 36 hours, any tPA complication within 36 hours, and discharge destination (home, hospice, inpatient rehabilitation facility, or skilled nursing facility).

The results of this study were interesting because they determined that patients taking anticoagulant therapy did have a higher risk for sICH if they were on anticoagulants just prior to the stroke when given tPA at the hospital. Despite this finding, patients who received tPA did not have higher in-hospital mortality and had better functional outcomes in terms of ambulatory status and mRS scores. This leaves the real judgement up to the health care professionals involved in different individual cases.

It is interesting when a study seems to come up with results that could lead health care professionals in two different directions.What factors could go into making the decision to use tPA or not when a patient presents with an acute ischemic stroke?

Xian Y, Federspiel JJ, Grau-Sepulveda M, et al. Risks and benefits associated with prestroke antiplatelet therapy among patients with acute ischemic stroke treated with intravenous tissue plasminogen activator. JAMA Neurol. 2016;73:50-59)