Please select the eligibility criteria that correspond to the clinical trial below.
Title: Dabigatran Following Transient Ischemic Attack and Minor Stroke
Brief Summary: 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.

Study Aims:

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.


Options:
A: Inclusion Criteria:

* Patients with Nonvalvular Atrial Fibrillation (NVAF) aged 80 years or older who are ineligible for available oral anticoagulation therapy

Exclusion Criteria:

* Patients with active bleeding
* Patients who have poorly controlled hypertension
* Patients who have liver dysfunction accompanied with disorder of blood coagulation
B: Inclusion Criteria:

* Patients must have documented atrial fibrillation on 2 separate occasions within 6 months before screening
* History of a prior stroke, transient ischemic attack or non-neurologic systemic embolism believed to be cardiac in origin, or at least two of the following risk factors: heart failure, hypertension, age 75 years or greater, diabetes mellitus

Exclusion Criteria:

* Significant mitral stenosis
* Transient atrial fibrillation caused by a reversible disorder
* Active internal bleeding
* Severe disabling stroke
* History of intracranial bleeding
* Hemorrhagic disorders
C: Inclusion Criteria:

1. Male or female patients
2. Must be \>18 years of age
3. Must have TIA or ischemic stroke (NIHSS score \<9 - see section 2.7 for further clarification)
4. Symptom onset is \< 72 hours prior to enrollment or Study therapy must initiated within 48 hours of symptom onset (in case where onset time cannot be established, it will be considered to be the time when the patient was lst know to be well
5. Informed consent must be obtained from either the patient or substitute decision maker (according to local REB policy) prior to any study related procedures being performed
6. All patients will have a MRI including DWI prior to randomization
7. DWI lesion volume must be \<25ml
8. Patients without DWI lesions, but a clinical history considered consistent with TIA, determined by the attending physician, can be included

Exclusion Criteria:

1. Patients with stroke mimics - such as seizures, migraine etc
2. Patients with contraindications to MRI including metallic implants
3. Patients with any past sensitivity to gadolinium contrast media will be eligible, but will not undergo PWI or contrast enhanced MRA (both optional sequences)
4. Patients with renal failure defined as Glomerular Filtration Rate (GFR) \< 30 ml/min
5. Patients deemed, as attending stroke physician, to have any ongoing bleeding risks or unsuitable for dabigatran therapy
6. Patients with MRI demonstrated additional pathology including arteriovenous malformations, intracranial aneurysms, tumors or abscess, which potentially increase the rise of bleed. Individuals with small incidental leasions, at low risk of bleed such as meningiomas may be included at the discretion of the investigator.
7. Patients with an acute DWI lesion volume of \>25 ml (DWI volume to be estimated using the ABC/2 technique 110)\*\*
8. Age \<18 years
9. Pregnant or breast feeding women.
10. Severe dysphagia necessitating naso-gastric (NG) feeding (dabigatran can not be delivered via NG tube)
11. Planned thrombolysis or endovascular intervention for the index event
12. Thrombolysis for ischemic stroke within the preceding 7 days
13. Planned carotid endarterectomy/carotid artery stent within 30 days Note: Carotid Investigations will be completed prior to enrolment. Patients with symptomatic stenoses and a planned carotid procedure will be excluded.
14. Any history of spontaneous intracranial bleeding
15. Clear indication for anticoagulation, including atrial fibrillation, mechanical cardiac valves, deep venous thrombosis, pulmonary embolism or known hypercoagulable state
16. Co-morbid illness with expected life expectancy of \<90 days
D: Inclusion Criteria:

* 21 years of age or older; male or female.
* Able to provide written informed consent.
* History of documented AF within the prior 12 months
* A moderate to high risk of stroke, as defined by CHADS2 index score of at least 2

Exclusion Criteria:

* Transient atrial fibrillation secondary to other reversible disorders
* Subjects with moderate or severe mitral stenosis, unresected atrial myxoma, or a mechanical heart valve
* Subjects with any contraindication for anticoagulant agents;
* Subjects with conditions associated with high risk of bleeding or have known or suspected hereditary or acquired bleeding disorders
* Females of childbearing potential including the following:

  * Females with a history of tubal-ligation
  * Females less than 2 years post-menopausal

Answer: C