One-week patch ECG reveals residual atrial fibrillation missed by repeated Holter monitoring after apparently successful catheter ablation

BACKGROUND Conventional 24-h Holter monitoring may overestimate rhythm cure after apparently successful catheter ablation (CA) for asymptomatic atrial fibrillation (AF). METHODS We prospectively enrolled 80 asymptomatic AF patients (70 ± 11 years; 78% men) who discontinued antiarrhythmic drugs and oral anticoagulation after repeated Holter recordings confirmed absence of recurrence. Extended rhythm surveillance was performed using a one-week patch ECG device (AT-Patch®, JLL Co., Ltd.). RESULTS Patch monitoring detected previously unrecognized residual AF in 4/80 patients (5.0%; 95% CI, 1.4-12.3%) despite multiple negative Holter recordings. During a mean follow-up of 5.4 ± 3.5 years, 76 patients (95%) remained free from clinically recognized recurrence without antiarrhythmic therapy. Non-sustained ventricular tachycardia was observed in 25 patients (31%). In a validation subgroup with known Holter-documented recurrence, patch ECG detected AF in 8/10 patients (80%; 95% CI, 44.4-97.5%), supporting the diagnostic sensitivity of one-week patch ECG monitoring. Based on the patch ECG findings, oral anticoagulation was resumed in three of the four patients with residual AF. No clinically significant skin complications occurred. CONCLUSION One-week patch ECG identified residual AF despite repeated negative Holter recordings, indicating that apparent rhythm cure based on intermittent monitoring may not reflect complete elimination of AF. Extended rhythm assessment may therefore provide a more rigorous evaluation of long-term ablation outcomes.