Is intravenous recombinant tissue plasminogen activator (r-tPA) safe in patients on Dabigatran?

Dabigatran etexilate is a newly approved oral anticoagulant indicated for stroke prevention in nonvalvular atrial fibrillation. There are no reliable, rapidly available laboratory markers to assess its anticoagulant activity. There is no data on the safety of r-tPA on patients who are on dabigatran and it is not known whether r-tPA is safe in patients who are on dabigatran with a normal activated partial thromboplastin time (aPTT).

We report the case of a 59-year-old male who is reported with right hemiparesis and global aphasia. Two days prior to admission he underwent elective cardioversion for atrial fibrillation. He had begun dabigatran at 150 mg BID 3 days before cardioversion. Five days after commencing dabigatran, and 10 h after the last oral dose he presented with these symptoms. Patient fulfilled the criteria for r-tPA including a normal aPTT (30 s), normal prothrombin time (INR = 1.0) and a normal creatinine clearance (glomerular filtration rate >60 mL/min/1.73 m(2)). A brain CT without contrast was normal. After extensive discussion with the family, with clear understanding of the risks and benefits of such an approach in a patient who has been on dabigatran, consent was obtained, and r-tPA (0.9 mg/kg alteplase) was given. Patient's hospital course remained uncomplicated and he was discharged 4 days after the initial symptoms to an acute rehabilitation facility and is currently on coumadin with INR therapeutic goal between 2 and 3.

More studies are needed to asses whether r-tPA might be safe in patients who are on dabigatran with a normal activated partial thromboplastin time and more than 10 h after the last dose.