Elsevier

Heart Rhythm

Volume 13, Issue 4, April 2016, Pages 836-844
Heart Rhythm

German ablation registry: Cryoballoon vs radiofrequency ablation in paroxysmal atrial fibrillation—One-year outcome data

https://doi.org/10.1016/j.hrthm.2015.12.007Get rights and content

Background

Although radiofrequency (RF) ablation has long been the standard of care for atrial fibrillation (AF) ablation, cryoballoon technology has emerged as a feasible approach with promising results. Prospective multicenter registry data referring to both ablation technologies in AF ablation are lacking so far.

Objective

The purpose of this study was to report data from the German ablation registry with respect to efficacy and safety in pulmonary vein ablation with different energy sources for paroxysmal AF after 1-year follow-up.

Methods

A total of 2306 patients with symptomatic paroxysmal AF from the German ablation registry were included in this analysis. The cohort was divided into two groups according to the ablation energy source used: cryoballoon and RF ablation. MACCE was defined as a combination of death, myocardial infarction, or stroke.

Results

AF recurrence rate after a single ablation procedure at 1 year follow-up was not significantly different between the two groups (45.8% after cryoablation and 45.4% after RF ablation, P = .87). Also, the rate of patients without AF recurrence and free of antiarrhythmic drug at 12-month follow-up was similar (cryoablation 44.2% and RF 41.4%, P = .25). MACCE occurred with an incidence of 0.7% within 500 days after cryoablation and 1.4% after RF ablation (P = .30). Persistent phrenic nerve palsy was more common after cryoablation compared to RF ablation (1.1% vs 0.3%, P <.05).

Conclusion

AF recurrence rate at 1-year follow-up was similar in RF ablation compared to cryoablation, whereas the spectrum and relevance of complications were significantly different between the two ablation methods. This finding might influence the choice of ablation method offered to the individual paroxysmal AF patient.

Introduction

Atrial fibrillation (AF) is associated with substantial morbidity and mortality from stroke and thromboembolism.1, 2, 3 Catheter ablation of pulmonary veins (PVs) is now well established as a curative treatment option for patients with symptomatic drug-refractory paroxysmal AF aiming at elimination or significant reduction of the AF burden.4, 5 Since the pioneering work in the late 1990s, radiofrequency (RF) technology has been the standard of care with evolving ablation strategies.6, 7 RF point-by-point ablation has shown high success rates in the treatment of patients with paroxysmal AF and persistent AF but is limited by several potential procedure-related complications, such as PV stenosis, pericardial effusion, atrio-esophageal fistula, thromboembolism, and left atrial (LA) flutter despite novel technologies.8, 9, 10, 11

The development of balloon catheters has enabled several new PV isolation strategies using cryotherapy, focused ultrasound, or endoscopic laser.12 Furthermore, cryoballoon therapy (Arctic Front, Medtronic, Minneapolis, MN) enables expeditious, complete, and safe circumferential isolations of the PV with proven low thrombogeneity.12, 13, 14 However, current available data with the cryoballoon therapy are primarily based on feasibility and nonrandomized clinical trials.15, 16, 17

Our group recently reported procedural parameters of the German ablation registry.18 Prospective multicenter registry outcome data referring to both ablation technologies in AF ablation therapy are lacking so far. Therefore, we report on the 1-year outcome data of all paroxysmal AF patients included in the German ablation registry with respect to efficacy and clinical outcome.

Section snippets

Study design and recruiting centers

The German ablation registry is a multicenter prospective registry including a total of 55 German electrophysiology centers. Registry approval of the local ethical committees was obtained.

The aim of the study was to monitor the current use and outcome of PV ablation methods, including RF ablation and cryoballoon ablation, in patients with paroxysmal AF in daily clinical practice. The registry was driven by the scientific interest of the participating hospitals and conducted by the Institut für

Patients characteristics and severity of AF-related symptoms

A total of 2306 patients (median age 62 [53–68] years, 1465 [63.5%] male) were included in the study. The proportion of males was similar in the RF and cryoballoon groups (63.3% vs 64.3%, P = .67). Patient characteristics did not differ significantly between both groups. An overview of comorbidities and patient characteristics is given in Table 1.

Symptomatic AF episodes before inclusion in the registry showed no significant differences between both groups. In patients undergoing RF ablation,

Discussion

The present analysis of the German ablation registry addresses a comparison of the cryoballoon approach with RF ablation in paroxysmal AF patients. Because ablation techniques and strategies vary among centers, it is of upmost interest to compare data on different ablation approaches, not only in selected patients in high-volume centers but in a setting that more closely reflects the practicing trend.

Conclusion

Freedom from AF recurrence 1 year after a single AF ablation using RF energy or cryoenergy in the “real-world” setting of the German ablation registry was lower than that of previously published trials of paroxysmal AF patients. Overall complication rates were similar, but the spectrum and type of complications differed significantly between the two ablation methods. These findings might have an impact on the choice of ablation method offered to the individual AF patient.

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    The 1-year follow-up and a former publication were partially supported by unrestricted grants from Medtronic, Biosense Webster, and Biotronik.

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