Long-term impact of catheter ablation on arrhythmia burden in low-risk patients with paroxysmal atrial fibrillation: The CLOSE to CURE study

Background Few studies evaluated the impact of catheter ablation (CA) on atrial tachyarrhythmia (ATA) burden in paroxysmal atrial fibrillation (AF). Objective In the prospective, patient-controlled CLOSE to CURE study, we determined the longer-term impact of optimized CA on ATA burden by using an insertable cardiac monitor (ICM). Methods A total of 105 patients with paroxysmal AF were implanted with an ICM 65 (interquartile range [IQR] 61–78) days before CA. CA consisted of contact force–guided pulmonary vein isolation targeting an intertag distance of ≤6 mm and a region-specific ablation index. The primary end point was reduction in ICM-detected ATA burden; secondary end points were single-procedure freedom from ATA, quality of life, and adverse events. Results The mean age was 62 ± 8 years; the median CHA2DS2-VASc score was 1 (IQR 1–2); and the median left atrial diameter was 43 (IQR 39–43) mm. After pulmonary vein isolation (1.13 ± 0.39 procedures per patient), median ATA burden decreased from 2.68% (IQR 0.09%–15.02%) at baseline to 0% (IQR 0%–0%) during the first year and to 0% (IQR 0%–0%) during the second year (reduction in ATA burden 100% [IQR 100%–100%]; P < .001). Single-procedure freedom from any ATA was 87% at 1 year and 78% at 2 years. Quality of life improved significantly across all scores. Adverse events occurred in 5 patients (4.8%). Conclusion CA has become an effective procedure in paroxysmal AF, with a major impact on ICM-detected ATA burden. Whereas conventional survival analysis suggests a progressive decline in efficacy, we observed that burden reduction is maintained at longer follow-up. These data imply that ATA burden is a more optimal end point for assessing ablation efficacy. Few studies evaluated the impact of catheter ablation (CA) on atrial tachyarrhythmia (ATA) burden in paroxysmal atrial fibrillation (AF). In the prospective, patient-controlled CLOSE to CURE study, we determined the longer-term impact of optimized CA on ATA burden by using an insertable cardiac monitor (ICM). A total of 105 patients with paroxysmal AF were implanted with an ICM 65 (interquartile range [IQR] 61–78) days before CA. CA consisted of contact force–guided pulmonary vein isolation targeting an intertag distance of ≤6 mm and a region-specific ablation index. The primary end point was reduction in ICM-detected ATA burden; secondary end points were single-procedure freedom from ATA, quality of life, and adverse events. The mean age was 62 ± 8 years; the median CHA2DS2-VASc score was 1 (IQR 1–2); and the median left atrial diameter was 43 (IQR 39–43) mm. After pulmonary vein isolation (1.13 ± 0.39 procedures per patient), median ATA burden decreased from 2.68% (IQR 0.09%–15.02%) at baseline to 0% (IQR 0%–0%) during the first year and to 0% (IQR 0%–0%) during the second year (reduction in ATA burden 100% [IQR 100%–100%]; P < .001). Single-procedure freedom from any ATA was 87% at 1 year and 78% at 2 years. Quality of life improved significantly across all scores. Adverse events occurred in 5 patients (4.8%). CA has become an effective procedure in paroxysmal AF, with a major impact on ICM-detected ATA burden. Whereas conventional survival analysis suggests a progressive decline in efficacy, we observed that burden reduction is maintained at longer follow-up. These data imply that ATA burden is a more optimal end point for assessing ablation efficacy.