Feasibility and Reliability of a Smartwatch to Detect Atrial Fibrillation After Cardiac Surgery: A Prospective Study

Background: Atrial fibrillation, the world's predominant cardiac arrhythmia, frequently emerges as a complication post-cardiac surgery, leading to serious outcomes like strokes, heart failures, and even death. Due to its often-silent nature, detecting it can be challenging. Smartwatches present a potential solution, offering screening that is more rigorous. Objective: This prospective observational study sought to assess the Withings Scanwatch's efficacy in identifying post-surgical atrial fibrillation. Methods: After cardiac surgery, patients received a Withings Scanwatch. Over a span of 24 hours, both the smartwatch's Photoplethysmography (PPG) sensor and standard telemetry kept track of any atrial fibrillation incidents. Results: At the end of the study, data from 260 patients was available for assessment. Atrial fibrillation was identified in 32 of these patients, either via telemetry or the smartwatch. Our data revealed a sensitivity of 69.0%, specificity of 98.7%, a PPV of 87.0%, and an NPV of 96.2%. Conclusions: This clinical study is the first to evaluate the PPG sensor of the Withings Scanwatch, and it shows that the Scanwatch has high accuracy in detecting atrial fibrillation. Thus, Scanwatch may support the conventional screening for atrial fibrillation, and potentially reducing complications and costs of atrial fibrillation. Because of lower than expected sensitivity this technology cannot replace conventional monitoring in postoperative patients.