Hemorrhagic transformation of ischemic brain tissue after t-PA thrombolysis as detected by MRI may be asymptomatic, but impair neurological recovery

Abstract

Background and purpose Symptomatic intracranial hemorrhages are typically clinically catastrophic and occur more frequently with tissue plasminogen activator (t-PA) therapy compared to without t-PA therapy. However, it has been unclear whether asymptomatic intracranial hemorrhage has clinical implications. Methods Consecutive anterior-circulation ischemic stroke patients treated with t-PA within 3 h of stroke onset were studied prospectively. Patients with symptomatic hemorrhages were excluded from the study. To identify the presence of early recanalization and intracranial hemorrhage, as well as to measure infarction volume, MRI examinations, including diffusion-weighted imaging, T2 ⁎, FLAIR, and MRA, were performed before and 1 h, 24 h, and 5–7 days after t-PA thrombolysis. At the same time, serial NIHSS scores were obtained. The independent predictors of dramatic recovery were determined using multivariate logistic regression analysis. Results 51 patients were enrolled in the present study. 22 patients (H group) had an asymptomatic hemorrhage. The NIHSS score of the Non-H group decreased, but that of the H group did not (11.5 ± 6.5 vs. 17.1 ± 6.5 at baseline, and 4.5 ± 6.8 vs. 14.3 ± 7.6 at 7 days; P = 0.0073 for ANOVA). Asymptomatic hemorrhage was more frequently seen in non-dramatic improvement group than in dramatic improvement group (65.5% vs. 13.6%, P = 0.0002). On multivariate logistic regression analysis using the variables that had a P < 0.1 on univariate analysis (AF, baseline NIHSS score, glucose, the presence of asymptomatic hemorrhage, ICA occlusion, early recanalization 1 h after t-PA infusion, and infarction volume 7 days after t-PA therapy), early recanalization (OR: 11.33; 95%CI: 1.064–120.704; P = 0.044) and infarction volume < 100 cm 3 (OR: 13.56; 95%CI: 1.020–180.125; P = 0.048) were independent factors for dramatic improvement, while asymptomatic hemorrhage (OR: 0.03; 95%CI: 0.002–0.537; P = 0.016) was an independent negative factor. Conclusion Asymptomatic hemorrhage was an independent negative factor for dramatic improvement. Asymptomatic hemorrhage after t-PA thrombolysis may be associated with neurological recovery.