Association of pretreatment blood pressure with tissue plasminogen activator-induced arterial recanalization in acute ischemic stroke

Background and Purpose - Elevated systolic blood pressure (SBP) and lack of early vessel recanalization are predictors of poor outcome among patients with stroke treated with systemic tissue plasminogen activator (tPA). We aimed to evaluate the potential relationship between pretreatment SBP and tPA-induced recanalization. Methods - Consecutive patients with acute ischemic stroke resulting from intracranial artery occlusion were treated with standard intravenous tPA and assessed with 2-MHz transcranial Doppler for arterial recanalization. Early arterial recanalization was determined with previously validated Thrombolysis in Brain Ischemia flow grading system at 120 minutes after tPA bolus. Functional outcome at 3 months was evaluated using the modified Rankin Scale. Results - A total of 351 patients received intravenous tPA ( mean age: 68.7 +/- 13.4 years, median National Institutes of Health Stroke Scale score 16.5). Patients with complete recanalization (n = 94) had lower mean pretreatment SBP values ( 152 +/- 23 mm Hg) than patients with incomplete or absent recanalization ( n = 257, 160 +/- 22 mm Hg, P = 0.010). Pretreatment SBP levels were inversely associated with complete recanalization ( OR per 10-mm Hg increase: 0.85; 95% CI: 0.74 to 0.98, P = 0.022) after adjustment for demographics, risk factors, stroke severity, pretreatment Thrombolysis in Brain Ischemia grades, and continuous versus intermittent exposure to transcranial Doppler. Although patients with poor functional 3-month outcomes ( modified Rankin Scale > 2) had higher pretreatment SBP values ( 160 +/- 25 mm Hg) than functionally independent patients ( 154 +/- 20 mm Hg, P = 0.027), pretreatment SBP levels were not independently associated with functional outcome on multivariable analysis. Age, complete recanalization, baseline National Institutes of Health Stroke Scale score, and time from symptom onset to tPA bolus were independent ( P < 0.05) predictors of 3-month outcome. Conclusion - Higher pretreatment SBP levels are associated with poor recanalization in patients with acute stroke treated with intravenous tPA.