Feasibility of repeated on-demand smartphone app-based approximation of time spent with atrial fibrillation and symptoms in patients after catheter ablation: Data from the ISOLATION study

BACKGROUND: The preferred outcome after atrial fibrillation (AF) ablation is reducing AF burden, reflected by time spent with AF. Digital tools provide novel strategies to approximate time spent with AF. OBJECTIVE: To assess the feasibility of repeated on-demand heart rhythm and symptom monitoring and analyze time spent with AF and symptoms over 12 months after AF ablation. METHODS: Patients were instructed to monitor heart rhythm and symptoms using a photoplethysmography-supported smartphone application three times daily for seven days on-demand at the 3-, 6-, and 12-month follow-ups. Metrics assessed included AF load and density and symptom load and density and symptom-rhythm correlation (SRC). RESULTS: A total of 191 patients (median age 65, 65% male) were included. Patient adherence (-7%, p=0.04) slightly declined over 12 months. Forty-five (24%) patients had AF recurrence and 136 (71%) symptom recurrence. In patients with high AF load and density at 3 months, 73% and 88% remained in the respective high class; in patients with low AF load and density, 0% remained in the low class. In patients with high symptom load and density, 94% and 75% remained in the respective high class; in patients with low symptom load and density, 0% remained in the low class. SRC was high, median 97% interquartile range 77-100%. CONCLUSION: Repeated on-demand smartphone-based monitoring is feasible after AF ablation. Patient adherence declined slightly over 12 months. At three months, high AF and symptom load reliably predicted the following year, while low AF and symptom load necessitate repeated monitoring.