Second-generation cryoballoon ablation for recurrent atrial fibrillation after an index cryoballoon procedure: a staged strategy with variable balloon size

Repeat cryoablation as a redo procedure for atrial fibrillation ablation: Is it a good choice?

BACKGROUND

Ablation of atrial fibrillation (AF), both cryoablation ablation (CBA) and radiofrequency catheter ablation (RFCA), have demonstrated to be safe and effective. About 1 in 3 patients may face a redo due to recurrence and the best technique is unknown. The aim of this study is to assess the efficacy of CBA as a repeat procedure in patients with prior CBA or RFCA.

METHODS

A nation-wide CBA registry (RECABA) was analyzed and patients were compared who had previously undergone CBA (Prior-CB) or RFCA (Prior-RF). The primary endpoint was AF recurrence at 12 months after a 3-month blanking period. A survival analysis was performed, univariate and multivariate Cox models were also built.

RESULTS

Seventy-four patients were included. Thirty-three (44.6%) were in the Prior-CB group and 41 (55.4%) in the Prior-RF. There were more reconnected pulmonary veins in the Prior-RF than in Prior-CB group (40.4% vs.16.5%, p = 0.0001). The 12-month Kaplan-Meier estimate of freedom from AF recurrence after the blanking period was 61.0% (95% confidence interval [CI] 41.4-75.8%) in the Prior-CB, and 89.2% (95% CI 73.6-95.9%) in the Prior-RF group (p = 0.002). Multivariate Cox regression pointed Prior-CB as the sole independent predictor of AF recurrence, with an adjusted HR of 2.67 (95% CI 1.05-6.79).

CONCLUSIONS

Repeat CBA shows higher rates of AF recurrences compared to CBA after a previous RFCA despite presenting less reconnected veins at the procedure. These data suggest that patients with AF recurrence after CBA may benefit from other ablation techniques after a recurrence. RECABA is registered at clinicaltrials.gov with the Unique Identifier NCT02785991.

A frozen decade: Ten years outcome of atrial fibrillation ablation using a single shot device for pulmonary vein isolation

AIMS

Cryoballoon-guided pulmonary vein isolation (CB-PVI) for symptomatic atrial fibrillation (AF) has become an established treatment option with encouraging results in terms of safety and efficacy. Data reporting on long-term data beyond a follow-up (FU) period of five years is scarce. This prospective study aimed to evaluate very long-term outcome after CB-PVI for AF.

METHODS

Data from consecutive patients treated with CB-PVI for symptomatic and drug refractory AF between 2005 and 2012 were analyzed. Patients with a FU of ≥9 years after index CB-PVI were included. All patients were continuously followed-up in our outpatient clinic. Arrhythmia recurrence was defined as AF or atrial tachycardia (AT) lasting >30s beyond a three-month blanking period.

RESULTS

A total of 385 patients (71% male) were included. Mean age was 58±10 years and paroxysmal AF was present in 93% of patients. Mean FU duration was 124±24 months. At the end of the observational period, 73% of all patients were in stable sinus rhythm after a mean of 2±0.8 ablation procedures. Patients with AF/AT recurrence were older (60±8vs.57±10 years; p=0.019), had a higher CHA₂ DS₂ -Vasc Score (2.47±1.46vs.1.98±1.50; p=0.01) and presented with a larger LA-diameter (43±5.6vs40±5.1 mm; p=0.002). The LA-diameter was also a significant predictor for AF/AT recurrence after CB-PVI (Odds Ratio: 0.939,95% CI [0.886, 0.992], p=0.03).

CONCLUSIONS

CB-PVI as index procedure for AF ablation resulted in favorable long-term outcome in symptomatic AF. CB-PVI might be recommended as interventional therapy in patients with lower LA remodeling. This article is protected by copyright. All rights reserved.

Cryoballoon Ablation for Persistent Atrial Fibrillation in a Patient with a Left Pneumonectomy

Pulmonary vein (PV) isolation (PVI) is the most important component of catheter ablation of atrial fibrillation (AF) and can be achieved by radiofrequency or cryoballoon ablation (CBA). The CBA system has shown excellent efficacy and safety in a number of clinical trials and is independent of the PV anatomy. However, pneumonectomy can significantly alter the anatomy posing a challenge to CBA. Few cases of PVI accomplished by CBA have been described in patients with lobectomy, but none in the pneumonectomy population. We describe a case of successful CBA for paroxysmal AF in a patient with a left total pneumonectomy.

[Practical guide for safe and efficient cryoballoon ablation for atrial fibrillation : Practical procedure, tips and tricks]

In the current guidelines on treatment of atrial fibrillation, cryoballoon-based catheter ablation of atrial fibrillation is recommended in addition to radiofrequency ablation and has become established as a standard procedure in the clinical routine of many centers for index pulmonary vein isolation. A safe, simplified and often durable pulmonary vein isolation can be achieved by a systematic approach. This review article provides a practical guide for all steps of cryoballoon-based pulmonary vein isolation, including preprocedural preparation and postinterventional follow-up. Both cryoballoon systems currently available on the market are considered.

Outcomes of atrial fibrillation ablation program based on single-shot techniques

Introduction

Single-shot techniques such as cryoballoon and multipolar phased pulmonary vein ablation catheter (PVAC) are an alternative to the point-by-point radiofrequency method for atrial fibrillation (AF) ablation. However, there is a lack of data concerning sequential use of single-shot techniques, that is, for both the index and redo ablation.

Aim

To assess long-term outcomes of the ‘single-shot techniques only’ AF ablation strategy.

Material and methods

We analyzed all consecutive AF ablations performed over a 10-year period (2009–2019) in a center where a ‘single-shot technique only’ principle was followed from the start of the AF ablation program. Kaplan-Meier AF-free survival curves were calculated and complications were assessed on the basis of our prospectively maintained database.

Results

A total of 597 patients (62.4 ±12.5 years) with paroxysmal (78.1%) or persistent (21.9%) AF entered the study and 655 AF ablation procedures were performed. In 96.5% of redos (n = 58) a different technique (mostly PVAC) was used than for the index ablation (mostly cryoballoon). The Kaplan-Meier estimates of 1, 2 and 5 years freedom from AF were 78.2%, 69.2%, and 56.0%, for the index ablation, and 80.3%, 76.1% and 68.3%, for the redo, respectively. The minor and major complication rates were 8.1%, and 4.0%, respectively.

Conclusions

An AF ablation program based solely on sequential use of two different single-shot techniques for both index and redo procedures is safe and effective. These observations might have important practical implications for new operators/centers starting AF ablation programs and for use of single-shot techniques for redo procedures.

Is the time of atrial fibrillation recurrence after cryoballoon ablation of paroxysmal atrial fibrillation influenced by the pattern of PV reconnections?

BACKGROUND

Pulmonary vein isolation (PVI) with 2nd-generation cryoballoon (CB) has been shown to be effective in the treatment of paroxysmal atrial fibrillation (AF). We describe pulmonary vein (PV) reconnection at repeat ablation in patients with AF recurrence after CB PVI and analyze the correlation between the time of AF recurrence and the observed PV reconnection patterns.

METHODS

Sixty-six patients undergoing a redo PVI for recurrent AF were enrolled 9.1 ± 2.6 months after the initial CB PVI procedure.

RESULTS

Ninety-two percent had PV reconnections with a mean of 1.97 ± 0.8 reconnected PVs/patient, and 52% of formerly isolated PVs were found reconnected. The highest reconnected rates were observed for left superior PVs (67%). Fifty-three percent of the patients had 2 reconnected PVs, no patient had all PVs reconnected, and 8% were without PV reconnection. There was a significant negative correlation between the time of AF recurrences and the extent of PV reconnections at redo PVI for patients with proven PV reconnection in more than one PV (R = 0.52, p < 0.001), while all patients without PV reconnection had AF recurrences within the first 9 months after PVI.

CONCLUSIONS

At redo ablation, most patients with recurrence of AF after CB PVI had PV reconnection(s). Patients with PV reconnection(s) showed a negative correlation between the number of reconnected PVs and the time of AF recurrence with more extensive PV reconnections resulting in earlier PV recurrences after the blanking period. Patients without PV reconnection experienced early AF recurrences, indicating non-PV triggers contributing for paroxysmal AF recurrences in these patients.

Comparison of pulmonary vein reconnection patterns after multielectrode phased radiofrequency- and cryoballoon ablation of atrial fibrillation

Background

Pulmonary vein isolation (PVI) using phased radiofrequency (RF) energy has been shown to be effective in the treatment of atrial fibrillation (AF).

Methods

We characterize and compare pulmonary vein (PV) reconnection at repeat ablation in patients with AF after initially successful PVI using phased RF technology (PVAC) or 2nd generation cryoballoon (CB). Eighty five patients undergoing redo PVI using multielectrode PVAC phased RF catheter and 66 patients after CB PVI were enrolled 9.7 ± 3.4 months after the initial ablation procedure.

Results

The percentage of patients with PV reconnection(s) was comparably high between both groups (93% PVAC and 92% CB). However, 75% of all PVs and left common trunks (CTs) isolated with PVAC were reconnected, compared with 52% reconnections after CB PVI (p < 0.001). A mean of 2.79 ± 1.2 PVs and CTs/patient were reconnected after PVAC PVI compared with 1.97 ± 0.8 in CB patients, p < 0.0001. No patients in the CB group had 4 reconnected PVs, while this pattern of reconnection was observed in 33% in the PVAC group (p < 0.0001). The percentage of patients in the PVAC group with ≥3 reconnected PVs was significantly higher compared with CB patients (56 patients (66%) vs. 17 patients (26%), p < 0.0001), while the percentage of patients with no PV reconnection was comparably low in PVAC and CB patients (7 and 8%, respectively). CTs were most frequently reconnected after PVAC PVI (94%) and left superior PVs after CB ablation (67%), respectively.

Conclusions

The number of patients with recurrent AF and PV reconnection(s) at redo PVI was comparably high between both groups. However, the extent and distribution of PV reconnections was different in many aspects, indicating more stable atrial lesions after CB PVI compared with PVAC technology.

Pulmonary vein reconnection following cryo-ablation: Mind the "Gap" in the carinae and the left atrial appendage ridge

Pulmonary vein (PV) isolation (PVI) remains cornerstone to ablation of atrial fibrillation (AF). For effective and durable PVI and thus fewer AF recurrences, lesion gaps in transmurality and contiguity responsible for PV reconnection (PVR) could only be addressed when one is cognizant of the potential location and sites where these lesion characteristics may be more prevalent and responsible for PVR. In the case of RF ablation, newer technologies incorporating contact force, time and power with automated monitoring of lesion formation, paying attention to difficult areas (carinae, left superior PV-LAA ridge, right inferior PV) and measuring inter-lesion distance may provide the tools to reduce PVR. On the other hand, the improved thermodynamic characteristics of the latest generation of cryoballloons and operator dexterity to achieve better PV occlusion, may be crucial determinants towards the direction of reduced PVR. Whether newer visualization tools, more vigilant testing during the index ablation procedure in these particular regions, prolonging or adding cryothermic applications, waiting longer to test for entrance and exit block, and/or use of provocative drug testing (isoproterenol/adenosine challenge) might help prevent future PVRs awaits further studies.

Repeat Ablation for Atrial Fibrillation Recurrence Post Cryoballoon or Radiofrequency Ablation in the FIRE AND ICE Trial

Background

The FIRE AND ICE trial assessed efficacy and safety of pulmonary vein (PV) isolation using cryoballoon versus radiofrequency current (RFC) ablation in patients with drug refractory, symptomatic, paroxysmal atrial fibrillation (AF). The purpose of the current study was to assess index lesion durability as well as reablation strategy and outcomes in trial patients undergoing a reablation procedure.

Methods

Patients with reablation procedures during FIRE AND ICEwere retrospectively consented and enrolled at 13 trial centers. The first reablation for each patient was included in the analysis. Documented arrhythmias before reablation, number and location of reconnected PVs, lesions created during reablations, procedural characteristics, and acute as well as long-term outcomes were assessed.

Results

Eighty-nine (36 cryoballoon and 53 RFC) patients were included in this study. Paroxysmal atrial fibrillation was the predominant recurrent arrhythmia (69%) before reablation. Reablations occurred at a median of 173 and 182 days (P=0.54) in the cryoballoon and RFC cohorts, respectively. The number of reconnected PVs was significantly higher in the RFC than the cryoballoon group (2.1±1.4 versus 1.4±1.1; P=0.010), which was driven by significantly more reconnected left superior PVs and markedly more reconnected right superior PVs. The number of (predominantly RFC) lesions applied during reablation was significantly greater in patients originally treated with RFC (3.3±1.3 versus 2.5±1.5; P=0.015) with no difference in overall acute success (P=0.70). After reablation, no differences in procedure-related rehospitalization or antiarrhythmic drug utilization were observed between cohorts.

Conclusions

At reablation, patients originally treated with the cryoballoon had significantly fewer reconnected PVs, which may reflect RFC catheter instability in certain left atrial regions, and thus required fewer lesions for reablation success. Repeat ablations were predominantly performed with RFC and resulted in similar acute success, duration of hospitalization, and antiarrhythmic drug prescription between the study cohorts.

Second-generation cryoballoon ablation for recurrent atrial fibrillation after an index procedure with radiofrequency versus cryo: Different pulmonary vein reconnection patterns but similar long-term outcome-Results of a multicenter analysis

INTRODUCTION

Repeated procedures are often needed for long-term success of atrial fibrillation ablation. There are scarce data regarding cryoballoon use for such procedure.

METHODS AND RESULTS

We analyzed acute effect and long-term follow-up of second-generation cryoballoon ablation, performed as a repeat procedure after an index radiofrequency vs cryoballoon ablation. Sixty-one patients from three centers were included. In 36 cases radiofrequency (RF-I) and in 25 cryoballoon ablation (CB-I) was the index procedure. During redo procedure, pulmonary vein reconnection was less frequent in CB-I vs RF-I (51.5% vs 66.9%; P = 0.017). After cryoballoon, left inferior (P =  0.027) and right superior (P = 0.06) pulmonary veins were less likely to exhibit reconnection. Moreover, patients after initial RF ablation frequently presented multiple-vein reconnection (P = 0.018), while patients after cryoablation more often had only one vein reconnected (P = 0.008). During reablation procedures, all 149 reconnected veins in both groups were isolated, with no differences in procedural parameters, except for procedure time, shorter in CB-I group (65.5 vs 71.1 minutes; P = 0.04). Transient phrenic nerve palsy was the only complication in both groups (5.6% and 8.0%; ns). After mean follow-up of 15 ± 9 months, 70.3% of patients were free from atrial fibrillation (AF), with no differences between the groups (P = 0.71). In multivariate Cox-regression analysis, the persistent form of arrhythmia (P = 0.009) and relapse in the blanking period (P = 0.0004) were the only independent predictors of AF recurrence.

CONCLUSIONS

The use of second-generation cryoballoon is associated with less frequent pulmonary vein reconnection compared with RF ablation. Cryoballoon is safe and effective for repeated AF ablation, regardless of the technique used for the initial procedure.