Pre–Tissue Plasminogen Activator Blood Pressure Levels and Risk of Symptomatic Intracerebral Hemorrhage

Abstract

Background and Purpose— From small pilot studies, uncontrolled pretreatment systolic blood pressure >185 mm Hg and diastolic blood pressure >110 mm Hg in patients with acute ischemic stroke were introduced in the National Institute of Neurological Diseases and Stroke rtPA Stroke Study as a contraindication for thrombolysis. We sought to determine if pretreatment blood pressure protocol violations in patients with acute ischemic stroke receiving intravenous tissue plasminogen activator are related to the subsequent risk of symptomatic intracranial hemorrhage (sICH). Methods— We reviewed medical records of consecutive ischemic stroke admissions treated with intravenous thrombolysis over a 10-year period at our tertiary care hospital. The National Institutes of Health Stroke Scale score on admission was used to determine baseline stroke severity. The closest documented blood pressure values to the time of tissue plasminogen activator bolus (range, 0 to 10 minutes) were considered as pretreatment blood pressure. Pretreatment blood pressure protocol violations were identified as systolic blood pressure >185 or diastolic blood pressure >110 mm Hg prebolus. sICH was defined as brain imaging evidence of intracranial hemorrhage with clinical worsening by the National Institutes of Health Stroke Scale score increase of ≥4 points. Results— Among 510 patients with ischemic stroke treated with intravenous tissue plasminogen activator (282 men; mean age, 65±15 years), sICH occurred in 31 patients (6.1%). Blood pressure protocol violations were present in 63 patients (12.4%) and they were more frequent in patients with sICH (26% versus 12%; P =0.019). After adjusting for demographic characteristics, onset-to-treatment time, baseline National Institutes of Health Stroke Scale, stroke risk factors and medications, pretreatment blood pressure protocol violations were independently associated with a higher likelihood of sICH (OR, 2.59; 95% CI, 1.07 to 6.25; P =0.034). Conclusions— These data support current guidelines advising not to use intravenous tissue plasminogen activator when pretreatment blood pressure exceeds the prespecified thresholds by showing that blood pressure protocol violations are independently associated with a higher likelihood of sICH.