Rationale: To date, anticoagulant therapy in acute stroke has also been limited by excess hemorrhagic events. The oral anticoagulant dabigatran is a novel agent, which has been shown to be associated with much lower intracranial hemorrhage rates. It has been suggested that this agent may provide the superior benefits of anticoagulation in acute stroke, without the concomitant increase in hemorrhage risk associated with heparin/LMWH or warfarin.
Study Design: DATAS II is a randomized, open label blinded endpoint trial. Participants (n=300) with TIA or ischemic stroke (NIHSS score <9) will be enrolled within 48 hours of symptom onset from approximately four (4) health care centres across Canada. All participants will have an MRI with DWI lesion volume < 25 ml. Participants will be randomized 1:1 to treatment with dabigatran for 30 days or ASA 81 mg daily (current standard of care). All stroke patients will initially be screened with a non-contrast CT scan of the brain. The first MRI will be performed within 48 hours of symptom onset. Imaging studies will be repeated at day 30. All patients will be assessed clinically at Day 30 and Day 90.
1. Establish the safety of early anticoagulation with the novel oral anticoagulant dabigatran in acute cerebrovascular syndrome patients.
2. Identify the rate of both symptomatic and asymptomatic hemorrhagic transformation (HT) associated with these treatments.
3. Identify predictors of HT associated with acute dabigatran treatment.
Hypothesis: The Investigators hypothesize that symptomatic HT rates in dabigatran and ASA treated patients will not be significantly different.
Study outcomes: The primary outcome is the rate of symptomatic hemorrhagic transformation (HT), defined as a parenchymal hematoma, which is >30% of the infarcted area on DWI, with substantial space- occupying effect, associated with clinical worsening (≥4 point increase in National Institutes of Health Stroke Scale (NIHSS) score) within 5 weeks of treatment initiation. The major secondary outcome the rate of asymtomatic HT see on day 30 MRI sequence.
- Dabigatran (Pradaxa)Drug
Intervention Desc: Dabigatran will be taken bid for 30 days post enrolment. The dose of dabigatran will be based on patient age and renal function. ARM 1: Kind: Experimental Label: Dabigatran therapy Description: 150 mg BID for 30 days (dose modification - reduced to 110mg BID in patients >80 years of age and/or an eGFR of 30-50 ml/min)
- Acetylsalicylic acid Drug
Intervention Desc: participants randomized to ASA therapy will be loaded with 325 mg of ASA, followed by 81 mg/day ARM 1: Kind: Experimental Label: Acetylsalicylic Acid thereapy Description: 325 mg loading dose then 81 mg/day for 30 days
- Allocation: Randomized
- Purpose: Treatment
- Endpoint: Safety Study
- Intervention: Parallel Assignment
|Type||Measure||Time Frame||Safety Issue|
|Primary||Rate of symptomatic hemorrhagic transformation||within 5 weeks of treatment initiation||Yes|
|Secondary||Rate of asymtomatic hemorrhagic transformation||day 30||Yes|