Sustained quality-of-life improvement post-cryoballoon ablation in patients with paroxysmal atrial fibrillation: Results from the STOP-AF Post-Approval Study.

BACKGROUND: Pulmonary vein isolation by catheter ablation is a class IA indication for the treatment of symptomatic, drug-refractory, paroxysmal atrial fibrillation (PAF). Quality of life (QoL) has been identified as a clinically meaningful endpoint but has not been comprehensively evaluated to date. OBJECTIVE: The purpose of this study was to evaluate the effects of cryoballoon ablation on long-term QoL. METHODS: As part of the STOP-AF Post-Approval Study, QoL was assessed using the Short Form-12 Health Survey (SF-12) along with evaluation of arrhythmia-related symptoms through 36 months. A multivariate linear mixed effects regression was used to determine the association between atrial fibrillation symptoms and QoL scores, and univariate linear regressions were used to assess predictors of 36-month change in QoL scores. RESULTS: Three hundred thirty-five subjects fully completed SF-12 forms at baseline, with 319, 308, 291, and 278 subjects completing surveys at the subsequent follow-up visits. Both physical and mental composite scores increased significantly from baseline (P <.001), and all arrhythmia symptoms significantly decreased from baseline (P <.001), with 62.0% of subjects reporting no symptoms at 6 months compared to 5.7% at baseline (P <.001). Presence of dyspnea and fatigue at baseline were univariate predictors of physical QoL improvement (P = .045 and 0.0497, respectively), whereas each year of age and each year of PAF duration were predictors of a decrease in mental QoL (P = .014 and .04, respectively). CONCLUSION: Cryoballoon ablation for treatment of PAF results in a significant, and sustained, QoL improvement. The observed improvement in physical and mental health likely may be mediated by a reduction in symptom and arrhythmia burden.

Long-Term Outcomes After Ablation for Paroxysmal Atrial Fibrillation Using the Second-Generation Cryoballoon: Final Results From STOP AF Post-Approval Study.

OBJECTIVES: STOP AF PAS (Sustained Treatment of Paroxysmal Atrial Fibrillation Post-Approval Study) is the first prospective, multicenter, 3-year study in North America to assess long-term safety and effectiveness of the cryoballoon for treatment of patients with drug-refractory symptomatic pAF. BACKGROUND: The STOP AF PAS was required by the U.S. Food and Drug Administration at the time of approval of the first-generation cryoballoon for the treatment of paroxysmal atrial fibrillation (pAF). The second-generation cryoballoon (CB2) was commercially released shortly after this trial was initiated. METHODS: The study was nonrandomized. Enrollment was completed with 344 eligible patients undergoing pulmonary vein isolation (PVI) using the CB2. Procedure-related safety and freedom from AF and symptomatic atrial flutter/atrial tachycardia through 3 years were determined. Documented atrial arrhythmias ≥30 s were considered treatment failures. RESULTS: Acute PVI was achieved in 99.3% (1,341 of 1,350) of veins. Mean follow-up was 34 ± 7 months. The rate of major complications was 5.8%, including a 3.2% rate of phrenic nerve injury, which resolved in all but 1 patient by 36 months. At 36 months, 11.7% of patients were prescribed antiarrhythmic agents, inclusive of "pill-in-the-pocket" administration. Freedom from AF was 81.6% at 12 months, 73.8% at 24 months, and 68.1% at 36 months. Freedom from AF and symptomatic atrial flutter/atrial tachycardia was 79.0% at 12 months, 70.8% at 24 months, and 64.1% at 36 months. Freedom from a repeat ablation procedure was 80.9% at 36 months. CONCLUSIONS: PVI using the CB2 was an effective treatment for patients with pAF, with freedom from all atrial arrhythmias of 64% at 36 months. (Sustained Treatment of Paroxysmal Atrial Fibrillation Post-Approval Study [STOP AF PAS]; NCT01456949).

Retrospective review of Arctic Front Advance Cryoballoon Ablation: a multicenter examination of second-generation cryoballoon (RADICOOL trial).

BACKGROUND: Pulmonary vein isolation (PVI) via catheter ablation is an approved therapy for patients with drug-refractory and symptomatic atrial fibrillation (AF). Furthermore, cryoballoon is now considered to be as effective as focal radiofrequency catheter ablation. This study examines the second-generation cryoballoon performance in a US multicenter review of real-world practices. METHODS: By retrospective chart collections, the long-term efficacy and safety of the cryoballoon procedure were assessed in 15 US centers. All patients had a history of drug-refractory symptomatic paroxysmal AF and were treated with a cryoballoon PVI strategy at the index ablation. RESULTS: Four hundred fifty-two patients were evaluated, and acute PVI was achieved in 99% of patients by cryoballoon catheter ablation. In 0.88% of patients (4/452), an additional focal ablation catheter was used to achieve acute PVI during the ablation procedure. Average procedure time was 128 (range 82 to 260) min, using an average of 17 (range 1 to 19) min of fluoroscopy. The most frequent adverse event was transient phrenic nerve injury (1.5%; 7/452 patients) which all resolved by the end of the procedure with no diaphragmatic dysfunction at discharge. There were no strokes, transient ischemic attacks, cardiac tamponade, atrioesophageal fistulas, or deaths during the study. At the 12-month efficacy endpoint, single-procedure success of freedom from atrial arrhythmia was 87% (393/452 patients). CONCLUSIONS: This real-world examination of the US practice demonstrates that second-generation cryoballoon ablation by PVI strategy is safe and effective among patients with paroxysmal AF.

Using Discrete Event Simulation to Model the Economic Value of Shorter Procedure Times on EP Lab Efficiency in the VALUE PVI Study.

BACKGROUND: The VALUE PVI study demonstrated that atrial fibrillation (AF) ablation procedures and electrophysiology laboratory (EP lab) occupancy times were reduced for the cryoballoon compared with focal radiofrequency (RF) ablation. However, the economic impact associated with the cryoballoon procedure for hospitals has not been determined. OBJECTIVE: Assess the economic value associated with shorter AF ablation procedure times based on VALUE PVI data. METHODS AND RESULTS: A model was formulated from data from the VALUE PVI study. This model used a discrete event simulation to translate procedural efficiencies into metrics utilized by hospital administrators. A 1000-day period was simulated to determine the accrued impact of procedure time on an institution's EP lab when considering staff and hospital resources. The simulation demonstrated that procedures performed with the cryoballoon catheter resulted in several efficiencies, including: (1) a reduction of 36.2% in days with overtime (422 days RF vs 60 days cryoballoon); (2) 92.7% less cumulative overtime hours (370 hours RF vs 27 hours cryoballoon); and (3) an increase of 46.7% in days with time for an additional EP lab usage (186 days RF vs 653 days cryoballoon). Importantly, the added EP lab utilization could not support the time required for an additional AF ablation procedure. CONCLUSIONS: The discrete event simulation of the VALUE PVI data demonstrates the potential positive economic value of AF ablation procedures using the cryoballoon. These benefits include more days where overtime is avoided, fewer cumulative overtime hours, and more days with time left for additional usage of EP lab resources.

Best practice guide for cryoballoon ablation in atrial fibrillation: The compilation experience of more than 3000 procedures.

BACKGROUND: Since the release of the second-generation cryoballoon (CB2; Arctic Front Advance(TM), Medtronic Inc) and its design modifications with improved cooling characteristics, the technique, dosing, and complication profile is significantly different from that of the first-generation cryoballoon. A comprehensive report of CB2 procedural recommendations has not been reported. OBJECTIVE: The purpose of this study was to review the current best practices from a group of experienced centers to create a user's consensus guide for CB2 ablation. METHODS/RESULTS: High-volume operators with a combined experience of more than 3000 CB2 cases were interviewed, and consensus for technical and procedural best practice was established. CONCLUSION: Comprehensive review of the CB2 ablation best practice guide will provide a detailed technique for achieving safer and more effective outcomes for CB2 atrial fibrillation ablation.

Comparison of resource utilization of pulmonary vein isolation: cryoablation versus RF ablation with three-dimensional mapping in the Value PVI Study.

BACKGROUND: Point-to-point focal radiofrequency (RF) catheter ablation for aberrant pulmonary vein triggers that manifest into atrial fibrillation (AF) is the traditional method for treating symptomatic drug-resistant paroxysmal AF (PAF) when an ablation procedure is warranted. More recently, pulmonary vein isolation (PVI) using the cryoballoon has been demonstrated to be safe and effective (STOP AF clinical trial). Currently, two small studies have reviewed the procedural efficiency when comparing cryoballoon to focal RF catheter ablation procedures; however, no multicenter study has yet reported on this comparison of the two types of ablation catheters. METHODS: A multicenter retrospective chart extraction and evaluation was conducted at seven geographically mixed cardiac care centers. The study examined procedural variables during ablation for PVI in PAF patients. RESULTS: In several procedural measurements, the two modalities were comparable in efficiencies, including: acute PVI >96%; length of hospital stay at approximately 27 hours; and about 30% usage of adenosine after procedural testing. However, when compared to RF catheters, the cryoballoon procedure demonstrated a 13% reduction in laboratory occupancy time (247 min vs 283 min), a 13% reduction in procedure time (174 min vs 200 min), and a 21% reduction in fluoroscopy time (33 min vs 42 min). Additionally, when comparing the material usage of both cryoballoon and RF catheters, the cryoballoon used more radiopaque contrast agent (78 cc vs 29 cc) while using less intraprocedural saline (1234 cc vs 2386 cc), intracardiac echocardiography (88% vs 99%), three-dimensional electroanatomic mapping (30% vs 87%), and fewer transseptal punctures (1.5 vs 1.9). CONCLUSION: This study is the first United States multicenter examination to report the procedural comparisons between the cryoballoon and focal RF catheters when used for the treatment of PAF patients. In this hospital chart review study, potential advantages were found when operating the cryoballoon with regard to hospital resource allocation. There was no statistical difference between cryoballoon and RF catheters for acute PVI success during the ablation procedure.