Hemorrhagic transformation after i.v. thrombolysis with rt-PA is excessively increased in effectively anticoagulated mice.
A) Mice without prior warfarin intake subjected to 3 h MCAO were treated with 10 mg/kg human rt-PA directly prior to reperfusion (left, n = 5). In comparison, mice anticoagulated to an INR of approximately 3 at the onset of cerebral ischemia (right, n = 5) showed a vast increase in hematoma volume after t-PA treatment. Statistical significance was essayed with student's unpaired, two-tailed t-test. ** p<0.01. B) Neuroscores were analyzed for statistical significance with a one-tailed Mann Whitney test and the p-value given as a Gaussian approximation (median values 4.5 and 5, p = 0.1970).