RESUMEN
Objective To assess the influence of atrial fibrillation on post-thrombolytic hemorrhagic transformation and functional prognosis in acute ischemic stroke patients within different time window.Methods We retrospectively reviewed the clinical and imaging data of patients of acute ischemic stroke with intravenous thrombolysis admitted from June 2009 to October 2013.According to onset-to-needle time,we divided patients into 3 groups and then assessed the effect of the comorbidity with atrial fibrillation on the occurrence of hemorrhagic transformation and favorable outcome (defined as modified Rankin Scale score≤2 at 90 days) after thrombolysis within different time window.Results A total of 345 patients were included in this study,among whom 101 (29.3％) were treated by intravenous thrombolysis within 3.0 h (≤3.0 h),157(45.5％) ＞3.0 h and≤4.5 h,87(25.2％) over 4.5 h(＞4.5 h).Atrial fibrillation was observed in 50.5％ (51/101) patients in ≤3.0 h group,37.6％ (59/157) in ＞3.0 h and≤4.5 h group and 40.2％ (35/87) in ＞ 4.5 h group (x2 =4.362,P =0.113).There were no statistically significant differences among these three groups about the rate of hemorrhagic transformation (hemorrhagic infarction:16.8％ (17/101),22.3％ (35/157),20.7％ (18/87),and parenchymal hematoma:5.0％ (5/101),10.2％ (16/157),10.3％ (9/87),x2 =4.278,P =0.370) and favorable outcome (51.5％ (52/101),53.5％ (84/ 157),47.1％ (41/87),x2 =0.913,P =0.633).Multivariate analysis demonstrated that atrial fibrillation was associated with hemorrhagic infarction for patients in ＞ 4.5 h group (OR =3.637,95％ CI 1.101-12.013,P =0.034),and the presence of atrial fibrillation independently predicted parenchymal hematoma for patients in ＞ 3.0 h and ≤4.5 h group (OR =3.757,95％ CI 1.133-12.457,P =0.030).There was no significant association between atrial fibrillation and favorable outcome at 90 days.Conclusions The presence of atrial fibrillation is not associated with the prognosis in thrombolytic patients.However,it enhanced the risk of parenchymal hematoma if patients were treated within the time window ＞ 3.0 h and ≤4.5h.