Impact of Protocol Deviations in Acute Ischemic Stroke Treated With Intravenous rt-PA Within 4.5 Hours After Symptom Onset

Background: There is limited experience in the community with intravenous tissue plasminogen activator (rt-PA) administered 3 to 4.5 hours after acute ischemic stroke (AIS) onset. Many patients do not meet entry criteria of pivotal clinical trials because of severe stroke, age >80, severe hypertension (sHTN), or history of previous stroke and diabetes. Whether rt-PA benefits these patients is unclear. Thus, we investigated the outcomes of stroke patients treated with rt-PA with or without these adverse clinical characteristics. Methods: Chart review of patients with AIS treated with intravenous rt-PA at a single institution. Outcomes at discharge were compared between patients with severe stroke, age >80, sHTN, or previous stroke/diabetes and those without these characteristics. Good outcome was defined as modified Rankin score (mRS) of 0 to 1. Analysis of variance and t tests were used to compare the outcomes. Results: Of the 118 cases analyzed, 103 (87%) were treated ≤3 hours and 15 (13%) between 3 and 4.5 hours. Sixty-three (53%) patients had severe stroke, age >80, sHTN, or previous stroke/diabetes, whereas 55 (47%) did not. Compared to controls, patients with these adverse characteristics were less likely to have good outcomes (35% vs 56%, p =.02). No patients treated within the 3- to 4.5-hour window experienced symptomatic intracranial hemorrhage (sICH). Eight patients treated between 3 and 4.5 hours had severe stroke, age >80, sHTN, or previous stroke/diabetes. Of these, 6 had poor outcomes. Conclusions: In a highly selected group of patients treated with intravenous rt-PA, lack of adherence to current guidelines did not improve stroke outcomes. This was related to more severe strokes at baseline, not sICH. Prospective studies of this patient group are needed.