Thrombolysis with alteplase 4.5-6 hours after acute ischemic stroke

The safety of intravenous (IV) thrombolysis when administered between 4.5 and 6 h after acute ischemic stroke with alteplase has not been established.

The objective of this study was to investigate the safety of IV alteplase thrombolysis within a 6-hour time frame following ischemic stroke.

Eligible patients were categorized as having treatment within 4.5 h or from 4.5 to 6 h and were evaluated for the following end points: disability at 90 days as measured by the modified Rankin Scale, incidence of mortality, and type 2 parenchymal hemorrhages.

100 patients were enrolled in our study (58 within 4.5 h after stroke and 42 between 4.5 and 6 h). After 90 days, 47.6% of the patients in the 4.5-6 h group reached independence in comparison to 44.8% patients in the 4.5 h group (p = 0.840). The incidence of type 2 parenchymal hemorrhage in the patients treated between 4.5-6 h and those treated within 4.5 h were 7.1 and 8.6%, respectively (p = 1.00). The incidence of mortality was 7.1 and 17.2% for the 4.5-6 and 4.5 h groups, respectively (p = 0.228).

IV thrombolysis in patients who fulfill the NINDS study criteria may still be considered up to 6 h after ischemic stroke.