Background and purpose: The present study clarifies associations between stroke outcomes after intravenous tissue plasminogen activator (tPA) and blood pressure (BP) as well as heart rate (HR) profiles.
Methods: We assessed 125 patients with stroke who received tPA within 3 h of onset. We obtained baseline, mean, maximum, minimum, and coefficient of variation values for BP and HR during the initial 24 h. The primary outcome was independence at 3 months corresponding to a modified Rankin Scale score of 2 or less. The secondary outcomes were early neurological improvement at 24 h and intracerebral hemorrhage (ICH) within 36 h.
Results: Among the patients, 64 (51%) achieved independence, 66 (53%) early improvement, and 26 (21%) developed ICH. The 24-h time courses of SBP (P = 0.033), pulse pressure (PP, P = 0.007), and HR (P < 0.001) were lower among patients who reached independence than among those who did not. After multivariate adjustment, 24-h mean levels of SBP (odds ratio 0.69, 95% confidence interval 0.48-0.97, per 10-mmHg increase), PP (0.63, 0.41-0.94), and HR (0.59, 0.42-0.80, per 10-bpm increase) were inversely associated with independence, as were their maximum and minimum values. In particular, mean SBP values were inversely associated with independence at 8-16 and 16-24 h (0.73, 0.54-0.97 and 0.66, 0.47-0.91, respectively), but not at 0-8 h (0.79, 0.57-1.07). Baseline and maximum SBP were inversely associated with early improvement. Maximum and coefficient of variation of SBP were associated with ICH.
Conclusion: Lower SBP, PP, and HR values during the initial 24 h after tPA, especially at 8 h thereafter, were associated with independence at 3 months.