Table 1.
Study inclusion and exclusion criteria.
| Inclusion criteria: |
| 1. Cryptogenic ischaemic stroke or TIA patients ≤14 days from symptom start. In Denmark, the time window for inclusion is up to 90 days from symptom start due to delay in echocardiography diagnostics. |
| 2. A stroke or TIA is considered to be cryptogenic if no cause can be determined despite an extensive workup according to the standard protocol of the participating centre. Before inclusion to the study, the following tests are required to establish the diagnosis of cryptogenic stroke or TIA:a |
| a. Brain MRI or CT.a |
| b. 12-Lead ECG for AF detection. |
| c. 24-h ECG monitoring for AF detection and premature atrial complex analysis. |
| d. Transthoracic echocardiography. |
| e. Transoesophageal echocardiography in patients aged ≤65 years. |
| f. Colour duplex ultrasound examination of the pre-cerebral arteries. |
| g. CTA or MRA of head and neck to rule out other causes of stroke. |
| h. Screening for thrombophilia <50 years of age. |
| 3. Age ≥18 years at onset of TIA/stroke. |
| 4. A participation consent form signed by the patient or a legally authorised representative. |
| Exclusion criteria: |
| 1. Known aetiology of TIA or stroke. |
| 2. TIA without documented cerebral ischemia on MRI diffusion weighted imaging. |
| 3. Untreated hyperthyroidism. |
| 4. Myocardial infarction <1 month prior to the stroke or TIA. |
| 5. Coronary bypass grafting <1 month prior to the stroke or TIA. |
| 6. Valvular heart disease requiring immediate surgical intervention. |
| 7. History of AF or atrial flutter. |
| 8. Patent foramen ovale |
| 9. Permanent indication for oral anticoagulation treatment at enrolment. |
| 10. Permanent contraindication for oral anticoagulation. |
| 11. Life expectancy <1 year. |
| 12. Pregnancy now or <3 months. |
| 13. An indication for an implantable pulse generator, implantable cardioverter-defibrillator, cardiac resynchronisation therapy or an implantable haemodynamic monitoring system. |
| 14. Patient otherwise not eligible for the study or adherent for follow-up (e.g. non-resident) or patient with concurrent disease which may affect clinical outcome (e.g. multiple sclerosis, cancer). |
CT: computed tomography; MRI: magnetic resonance imaging.
aTIA cases with acute non-lacunar infarct on MRI diffusion weighted imaging are included as TIA events.