Performance of Wrist Photoplethysmography in Monitoring Atrial Fibrillation in Post Cardiac Surgery Patients

New methods for unobtrusive long-term monitoring of arrhythmias are needed. We evaluated the accuracy of wrist-worn optical heart rate monitor in beat-to-beat interval estimation and performance in classifying the rhythm in sinus or atrial fibrillation with 30 post cardiac surgery patients (69.3 ± 6.9 years) in 24-hour recordings. The recordings were made during the first post-operative days when the patients are still relatively stationary and are in high risk of getting post-surgery atrial fibrillationThe results show 10.04 ms mean absolute error in beat-to-beat intervals. Atrial fibrillation was analysed in 5-minute segments. 100% sensitivity and 96.1% specificity were obtained. The specificity was increased to 99.74% when the data segments with large number of ventricular and supra ventricular extra systoles were removed. The results show that the performance of optical heart rate monitoring technology is adequate for screening of atrial fibrillation at least in stationary conditions.