Implementing a patient-led smartwatch electrocardiogram (ECG) follow-up strategy into an existing clinical pathway after atrial fibrillation (AFib) ablation is feasible and can provide accurate data for evaluation, according to findings from a randomized controlled trial published Jan. 28 in JACC: Advances.

Nikhil Ahluwalia, MBBS, PhD, et al., included 168 participants (mean age 60.5 ± 9.9 years, 31% female, 50% with persistent AFib) undergoing first-time AFib ablation. Patients were randomized to either an Apple Watch-based protocol or standard follow up.

Patients in the smartwatch cohort recorded a median 170 (IQR 93-380) ECGs over the course of 12 months, transmitting a median 1.9% (0.0-8.3) for review. Symptom-annotated ECGs had a greater likelihood of showing AFib than unannotated ECGs (odds ratio 16.1, 95% CI 13.0-19.9, p<0.001).

Watch-derived labels for AFib and sinus rhythm had positive predictive values of 0.96 and 0.95, respectively. However, one-third of ECGs were unclassified, meaning the smartwatch labeled them as high heart rate, low heart rate, poor recording, or inconclusive.

"This trial demonstrates that a structured, patient-led smartwatch ECG workflow can be operationalized and systematically evaluated within routine, post-ablation care using commercially available technology," write the authors.

They expand on primary clinical outcomes in an accompanying report published in JACC, noting that patients in the smartwatch cohort had a greater chance of AFib recurrence detection post ablation (hazard ratio 1.83; 95% CI 1.15-2.93; p=0.010) and exhibited a shorter time to first detection (median 116 days in Apple Watch cohort vs. 132 days in standard cohort).

Additionally, participants in the smartwatch cohort were less likely to be hospitalized (incidence rate ratio 0.46; 95% CI 0.25-0.82; p=0.009).

"Patient-led [Apple Watch]-based monitoring after [AFib catheter ablation] reduced the time to recurrent arrythmia detection, increased the overall detection yield, and was associated with fewer unplanned hospitalizations compared to standard care," state Ahluwalia and colleagues.