Perception of atrial fibrillation before and after radiofrequency catheter ablation - Relevance of asymptomatic arrhythmia recurrence

Background - The objective of this study was to assess the incidence and impact of asymptomatic arrhythmia in patients with highly symptomatic atrial fibrillation (AF) who qualified for radiofrequency (RF) catheter ablation. Methods and Results - In this prospective study, 114 patients with at least 3 documented AF episodes together with corresponding symptoms and an ineffective trial of at least 1 antiarrhythmic drug were selected for RF ablation. With the use of CARTO, circumferential lesions around the pulmonary veins and linear lesions at the roof of the left atrium and along the left atrial isthmus were placed. A continuous, 7-day, Holter session was recorded before ablation, right after ablation, and after 3, 6, and 12 months of follow-up. During each 7-day Holter monitoring, the patients recorded quality and duration of any complaints by using a detailed symptom log. More than 70 000 hours of ECG recording were analyzed. In the 7-day Holter records before ablation, 92 of 114 patients (81%) had documented AF episodes. All episodes were symptomatic in 35 patients (38%). In 52 patients (57%), both symptomatic and asymptomatic episodes were recorded, whereas in 5 patients (5%), all documented AF episodes were asymptomatic. After ablation, the percentage of patients with only asymptomatic AF recurrences increased to 37% ( P < 0.05) at the 6-month follow-up. An analysis of patient characteristics and arrhythmia patterns failed to identify a specific subset who were at high risk for the development of asymptomatic AF. Conclusions - Even in patients presenting with highly symptomatic AF, asymptomatic episodes may occur and significantly increase after catheter ablation. A symptom-only - based follow-up would substantially overestimate the success rate. Objective measures such as long-term Holter monitoring are needed to identify asymptomatic AF recurrences after ablation.