Abstract 153: Long-term Monitoring For Paroxystic Atrial Fibrillation In Cryptogenic Stroke: Preliminary Results Of The Surprise Study

The SURPRISE project aims at estimating the frequency and the burden of paroxystic atrial fibrillation in patients with apparent cyptogenic minor stroke or TIA. Long term monitoring by use of a implanted Reveal XT ® is used with the aim of obtaining complete data on arrhythmia long term after minor stroke/TIA. In short, patients with cryptogenic (including no history of AF, and no signs of AF on telemetry during hospital stay) minor stroke or DWI-positive TIA, modified Rankin Scale ≤ 2, and no contraindications to anticoagulation treatment are included after informed consent from a comprehensive stroke unit. A Reveal XT®, an atrial fibrillation sensitive loop-recorder, is implanted subcutaneously, and patients are monitored for up to 3 years and followed up clinically by regular visits. Arrhythmia episodes are adjudicated by a senior consultant cardiologist specialized in electrophysiology. Primary endpoints of the study are 1) episodes AFIB and 2) burden of AFIB. Further 1) persisting AF and 2) recurrent stroke/TIA, and 3) treatment change to anticoagulation based on monitoring events. The study aims at enrolling a total of 100 patients, which is expected before end 2011. Results Until today (august 15 th 2011) we have included 52 patients; 43 are so far implanted and actively transmitting data. In 8 patients (18.6 %) AFIB has been documented on monitoring and have consequently been anticoagulated. No recurrent events have occurred so far. Long term monitoring was instrumental in treatment change in 18.6 % of patients. AF patients have a mean age of 64.5 years vs 57.5 years in no AF patients (p= 0.017) AF patients also have a higher CHADS2 score 3.25 vs 2.34 (p=0.013) The average time from stroke onset to first recorded event of AFIB is 133 days (see fig.1) These preliminary data suggest that paroxystic AF is frequent in cryptogenic stroke even after telemetry and may occur after a long free interval. Long term monitoring frequently results in change of treatment. Older patients and patients with more risk factors are more likely to have paroxystic AF. As anticoagulant treatment improves prognosis in patients with AF after stroke, better identification of patients with AF is likely to reduce the burden of recurrent stroke.