Aims Delay of progression from paroxysmal to persistent atrial fibrillation (AF) is an important measure of long-term success of AF treatment. However, published data on the impact of catheter ablation on AF progression are limited. This study evaluates whether radiofrequency (RF) catheter ablation delays the progression of AF compared with antiarrhythmic drug (AAD) treatment using current AF management guidelines. Methods This prospective, randomized, controlled, two-arm, open-label trial was conducted at 29 hospitals and medical centres across 13 countries. Patients were randomized 1 : 1 to RF ablation or AAD treatment. The primary endpoint was the rate of persistent AF/atrial tachycardia (AT) at 3 years. Results After early study termination following slow enrolment, 255 (79%) of the planned 322 patients were enrolled (RF ablation, n = 128, AAD, n = 127); 36% of patients in the RF ablation group and 41% in the AAD group completed 3 years of follow-up. For the primary endpoint, the Kaplan–Meier estimate of the rate of persistent AF/AT at 3 years was significantly lower with RF ablation [2.4% (95% confidence interval (CI), 0.6–9.4%)] than with AAD therapy [17.5% (95% CI, 10.7–27.9%); one-sided P = 0.0009]. Patients ≥65 years were ∼4 times more likely to progress to persistent AF/AT than patients <65 years, suggesting RF ablation can delay disease progression [hazard ratio: 3.87 (95% CI, 0.88–17.00); P = 0.0727]. Primary adverse events were reported for eight patients in the RF ablation group. Conclusions Radiofrequency ablation is superior to guideline-directed AAD therapy in delaying the progression from paroxysmal to persistent AF.

BackgroundThis study sought to assess payer costs following cryoballoon or radiofrequency current (RFC) catheter ablation of paroxysmal atrial fibrillation in the randomized FIRE AND ICE trial.Methods and ResultsA trial period analysis of healthcare costs evaluated the impact of ablation modality (cryoballoon versus RFC) on differences in resource use and associated payer costs. Analyses were based on repeat interventions, rehospitalizations, and cardioversions during the trial, with unit costs based on 3 national healthcare systems (Germany [€], the United Kingdom [£], and the United States [normal$]). Total payer costs were calculated by applying standard unit costs to hospital stays, using International Classification of Diseases, 10th Revision diagnoses and procedure codes that were mapped to country‐specific diagnosis‐related groups. Patients (N=750) randomized 1:1 to cryoballoon (n=374) or RFC (n=376) ablation were followed for a mean of 1.5 years. Resource use was lower in the cryoballoon than the RFC group (205 hospitalizations and/or interventions in 122 patients versus 268 events in 154 patients). The cost differences per patient in mean total payer costs during follow‐up were €640, £364, and normal$925 in favor of cryoballoon ablation (P=0.012, 0.013, and 0.016, respectively). This resulted in trial period total cost savings of €245 000, £140 000, and normal$355 000.ConclusionsWhen compared with RFC ablation, cryoballoon ablation was associated with a reduction in resource use and payer costs. In all 3 national healthcare systems analyzed, this reduction resulted in substantial trial period cost savings, primarily attributable to fewer repeat ablations and a reduction in cardiovascular rehospitalizations with cryoballoon ablation.Clinical Trial RegistrationURL: http://www.clinicaltrials.gov. Identifier: NCT01490814.

Aims Atrial fibrillation (AF) ablation has made huge progress with respect to innovation, efficacy, and safety, however, complications are still present. Recent studies examined various predictors of complications. However, limited data exist regarding the role of a repeat procedure. Our aim was the prospective evaluation of the incidence and predictors of complications related to AF ablation procedures in consecutive patients, including repeat procedures. Methods and results All ablation procedures for AF between January 2013 and December 2015 were analysed in our electrophysiology laboratory. During the study period 1243 procedures were analysed [394 female, median age 62 (55–69)]. Overall complication rate was 6.84%, major complication rate was 2.82%. Major complications were the following: 18 pericardial tamponades; 5 pseudoaneurysms; 1 arteriovenous fistula; 6 thromboembolic cerebrovascular events; 3 pulmonary vein stenosis; and 2 atrioventricular blocks. No atrio-oesophageal fistula or procedure related death occurred. Univariate analysis for overall complications showed that age ≥ 65 years ( P = 0.0231), female gender ( P = 0.0438), hypertension ( P = 0.0488), CHA 2 DS 2 -VASc score ≥ 2 ( P = 0.0156), and previous AF ablation procedure ( P < 0.0001) is associated with higher risk for adverse events. Multivariate analysis showed that the only independent predictor of overall complications was previous AF ablation procedure ( P < 0.0001). Similarly, the only predictor of major complications was previous AF ablation procedure ( P < 0.0001). Conclusion Incidence of complications associated with AF ablation in our high volume electrophysiology laboratory is similar to other cohorts. The only independent predictor of complications was previous AF ablation procedure in our series.

Background - Atrial fibrillation (AF) recurrence following catheter ablation remains high. Recent studies have shown a relation between epicardial adipose tissue (EAT) and AF. EAT secretes several pro- and anti-inflammatory adipokines that directly interact with the adjacent myocardium. The aim of the current study was to evaluate whether posterior left atrial (LA) adipose tissue attenuation, as marker of inflammation, is related to AF recurrences after catheter ablation. Methods - Consecutive patients with symptomatic AF referred for first AF catheter ablation who underwent CT were included. The total EAT and posterior LA adipose tissue were manually traced and adipose tissue was automatically recognized as tissue with Hounsfield units (HU) between -195 and -45. The attenuation value of the posterior LA adipose tissue was assessed and the population divided according to the mean HU value (-96.4 HU). Results - In total, 460 patients (66% male, age 61 ± 10 years) were included in the analysis. After a median follow-up of 18 months (IQR 6-32), 168 (37%) patients had AF recurrence. Patients with higher attenuation (≥-96.4 HU) of the posterior LA adipose tissue showed higher AF recurrence rates compared to patients with lower attenuation (<-96.4 HU) (log-rank test p=0.046). Univariate analysis showed an association between AF recurrence and higher posterior LA adipose tissue attenuation (≥-96.4 HU) (p<0.05). On multivariable analysis posterior LA adipose tissue attenuation (HR 1.26; 95% CI 0.90-1.76; p=0.181) remained a promising predictor of AF recurrence following catheter ablation. Conclusions - Posterior LA adipose tissue attenuation is a promising predictor of AF recurrence in patients who undergo catheter ablation. Higher adipose tissue attenuation might signal increased local inflammation and serve as an imaging biomarker of increased risk of AF recurrence.

Introduction Our pilot study aimed to evaluate the role of local impedance drop in lesion formation during pulmonary vein isolation with a novel contact force sensing ablation catheter that records local impedance as well and to find a local impedance cut-off value that predicts successful lesion formation. Materials and methods After completing point-by-point radiofrequency pulmonary vein isolation, the success of the applications was evaluated by pacing along the ablation line at 10 mA, 2 ms pulse width. Lesions were considered successful if loss of local capture was achieved. Results Out of 645 applications, 561 were successful and 84 were unsuccessful. Compared to the unsuccessful ablation points, the successful applications were shorter (p = 0.0429) and had a larger local impedance drop (p<0.0001). There was no difference between successful and unsuccessful applications in terms of mean contact force (p = 0.8571), force-time integral (p = 0.0699) and contact force range (p = 0.0519). The optimal cut-point for the local impedance drop indicating successful lesion formation was 21.80 Ohms on the anterior wall [AUC = 0.80 (0.75–0.86), p<0.0001], and 18.30 Ohms on the posterior wall [AUC = 0.77 (0.72–0.83), p<0.0001]. A local impedance drop larger than 21.80 Ohms on the anterior wall and 18.30 Ohms on the posterior wall was associated with an increased probability of effective lesion creation [OR = 11.21, 95%CI 4.22–29.81, p<0.0001; and OR = 7.91, 95%CI 3.77–16.57, p<0.0001, respectively]. Conclusion The measurement of the local impedance may predict optimal lesion formation. A local impedance drop > 21.80 Ohms on the anterior wall and > 18.30 Ohms on the posterior wall significantly increases the probability of creating a successful lesion.