Cryoballoon Ablation for the Treatment of Atrial Fibrillation: A Meta-analysis

Transseptal Puncture and Cryoballoon Ablation of Atrial Fibrillation in Patients with Atrial Septal Occluder or Atrial Septal Defect Surgical Repair: A Single Center Experience

BACKGROUND

Atrial fibrillation (AF) is a common arrhythmia in patients with atrial septal defect (ASD). Cryoballoon ablation (CA) is a safe and efficient method for pulmonary vein (PV) isolation in the treatment of AF. Achieving left atrial access may be difficult in patients with atrial septal occluders (ASO) or surgical repair of ASD. The aim of this study was to present our experience with the efficacy and safety of transseptal puncture and AF ablation in CA in this subset of patients.

METHODS

We retrieved our data about patients with ASO or surgical repair of ASD undergoing cryoballoon AF ablation procedures at our center between August 2019 and January 2022.

RESULTS

Nine patients (age 43.88 ± 9.73 years) with AF (5 paroxysmal and 4 persistent) and ASO or surgical repair of ASD were enrolled. All three patients had a 28 mm Amplatzer ASO device which occupied the whole septum, and direct puncture through the ASO was performed. Sequential balloon dilatation was performed in 2 patients with surgical ASD repair and all 3 patients with ASO. Four of 6 patients (66.7%) in the surgical repair group required transesophageal echocardiography during transseptal puncture. The endpoint of the procedure, isolation of all PVs, was achieved in all 9 patients. None of the patients had evidence of an interatrial shunt or pericardial effusion at the end of the procedure. Total procedural time (123 ± 28 minutes vs. 63 ± 21 minutes, P = .024) and total fluoroscopy time (41 ± 5 minutes vs. 23 ± 8 minutes, P = .024) were significantly higher in the percutaneous closure group.

CONCLUSIONS

In patients with ASO or surgical repair of ASD, CA of AF might be feasible, safe, and effective. The balloon dilatation of the interatrial septum (IAS) might assist transseptal access through the ASO or a surgically repaired thickened IAS.

Gunawardene M, Eickholt C, Hartmann J, Schmoeckel M, Schäffer B. Medical, Interventional, and Surgical Treatment Strategies for Atrial Fibrillation

BACKGROUND

Atrial fibrillation is the most common type of cardiac arrhythmia; the lifetime risk for a 55-year-old person to develop atrial fibrillation is 37%. In recent years, years there have been various distinct changes in the clinical management of AF.

METHODS

This review is based on a selective search for literature on the treatment of AF and the prevention of thromboembolic complications. The updated guideline of the European Society of Cardiology (ESC) for the diagnosis and treatment of AF was also taken into consideration.

RESULTS

The main components of AF management are the comprehensive treatment of risk factors and concomitant diseases, as well as the prevention of thromboembolic complications, usually with non-vitamin-K-dependent oral anticoagulants or vitamin K antagonists, according to individual risk stratification. Beyond this, either rate or rhythm control are viable treatment concepts. Symptomatic patients in whom reversible causes have been ruled out should be offered rhythm-control therapy early in their course. In patients with risk factors and/or heart failure, an early rhythm control strategy has been found to be beneficial. As antiarrhythmic drugs often prove to be ineffective over the long term, catheter ablation is now becoming increasingly important in AF management.

CONCLUSION

The clinical management of atrial fibrillation consists of a multimodal approach with risk stratification, lifestyle modification, prevention of thromboembolism, and, if possible, early rhythm control therapy.

Second-generation cryoballoon versus contact force radiofrequency ablation for atrial fibrillation: an updated meta-analysis of evidence from randomized controlled trials

Catheter ablation has been recommended for patients with symptomatic atrial fibrillation (AF), with pulmonary vein isolation being the cornerstone of the ablation procedure. Newly developed technologies, such as cryoballoon ablation with a second-generation cryoballoon (CB2) and the contact force radiofrequency (CF-RF) ablation, have been introduced in recent years to overcome the shortcomings of the widely used RF ablation approach. However, high-quality results comparing CB2 and CF-RF remain controversial. Thus, we conducted this meta-analysis to assess the efficacy and safety between CB2 and CF-RF using evidence from randomized controlled trials (RCTs). Databases including Embase, PubMed, the Cochrane Library, and ClinicalTrials.gov were systematically searched from their date of inception to January 2021. Only RCTs that met the inclusion criteria were included for analysis. The primary outcome of interest was freedom from atrial tachyarrhythmia (AT) during follow-up. Secondary outcomes included procedure-related complications, procedure time and fluoroscopy time. Six RCTs with a total of 987 patients were finally enrolled. No significant differences were found between CB2 and CF-RF in terms of freedom from AT (relative risk [RR] = 1.03, 95% confidence interval [CI] 0.92-1.14, p = 0.616) or total procedural-related complications (RR = 1.25, 95% CI 0.69-2.27, p = 0.457). CB2 treatment was associated with a significantly higher risk of phrenic nerve palsy (PNP) than CF-RF (RR = 4.93, 95% CI 1.12-21.73, p = 0.035). The occurrences of pericardial effusion/tamponade and vascular complications were comparable between the CB2 and CF-RF treatments (RR = 0.41, p = 0.398; RR = 0.82, p = 0.632). In addition, CB2 treatment had a significantly shorter procedure time than CF-RF (weighted mean difference [WMD] = - 20.75 min, 95% CI - 25.44 ~ - 16.05 min, P < 0.001), whereas no difference was found in terms of fluoroscopy time (WMD = 4.63 min, p = 0.179). CB2 and CF-RF treatment are comparable for AF patients regarding freedom from AT and procedure-related complications. Compared to CF-RF, CB2 treatment was associated with a shorter procedure time but a higher incidence of PNP. Further large-scale studies are warranted to compare these two techniques and provide an up-to-date recommendation.

Effectiveness and safety of a single freeze strategy of cryoballoon ablation of atrial fibrillation: an EHRA systematic review and meta-analysis

To conduct a systematic review and meta-analysis to compare the effectiveness and safety of cryoballoon ablation of atrial fibrillation (AF) performed using a single freeze strategy in comparison to an empiric double ('bonus') freeze strategy. We systematically searched MEDLINE, EMBASE, and CENTRAL databases from inception to 12 July 2020, for prospective and retrospective studies of patients undergoing cryoballoon for paroxysmal or persistent AF comparing a single vs. bonus freeze strategy. The main outcome was atrial arrhythmia-free survival and eligible studies required at least 12 months of follow-up; the primary safety outcome was a composite of all complications. Study quality was assessed using the Cochrane risk of bias tool and the Newcastle-Ottawa Scale. Thirteen studies (3 randomized controlled trials and 10 observational studies) comprising 3163 patients were eligible for inclusion (64% males, 71.5% paroxysmal AF, mean CHA2DS2-VASc score 1.3 ± 0.9). There was no significant difference in pooled effectiveness between single freeze strategy compared to double freeze strategy [relative risk (RR) 1.03; 95% confidence interval (CI): 0.98-1.07; I2 = 0%]. Single freeze procedures were associated with a significantly lower adverse event rate (RR 0.72; 95% CI: 0.53-0.98; I2 = 0%) and shorter average procedure time (90 ± 27 min vs. 121 ± 36 min, P < 0.001). A trend for lower risk of persistent phrenic nerve palsy was observed (RR 0.61; 95% CI: 0.37-1.01; I2 = 0%). The quality of included studies was moderate/good, with no evidence of significant publication bias. Single freeze strategy for cryoballoon of AF is as effective as an empiric double ('bonus') freeze strategy while appearing safer and probably quicker (PROSPERO registration number CRD42020158696).

Comparative efficacy and safety of catheter ablation interventions for atrial fibrillation: comprehensive network meta-analysis of randomized controlled trials

PURPOSE

Point-by-point radiofrequency (RF) ablation has been the cornerstone of pulmonary vein isolation (PVI) for patients with atrial fibrillation (AF); however, it remains a complex and time-consuming procedure. Many novel AF catheter ablation (CA) techniques have been introduced, but whether they represent valuable alternatives remains controversial. Thus, we conducted a network meta-analysis to comprehensively evaluate the efficacy and safety of different CA interventions.

METHODS

We systematically searched several databases (Embase, PubMed, the Cochrane Library, and ClinicalTrials.gov ) from inception to March, 2020. The primary outcomes of interest were freedom from atrial tachyarrhythmia (AT) and procedure-related complications; secondary outcomes included procedure time and fluoroscopy time.

RESULTS

Finally, 33 randomized controlled trials (RCTs) with a total of 4801 patients were enrolled. No significant differences were found among the different interventions in terms of primary efficacy or safety outcomes. PVAC was most likely to have the shortest procedure time (Prbest = 61.5%) and nMARQ the shortest fluoroscopy time (Prbest = 60.6%); compared with conventional irrigated RF (IRF) ablation, cryoballoon ablation (CBA) showed comparable clinical efficacy and safety; CBA with second-generation CB (CB2) had a significantly shorter procedure time than IRF with contact force technology (CF-IRF) (WMD = - 20.75; p = 0.00).

CONCLUSION

There is insufficient evidence to suggest that one CA technique is superior to another. However, PVAC may be associated with a shorter procedural duration, and the CB2 catheters also seemed to reduce the procedure time compared with that of CF-IRF. Further large-scale studies are warranted to compare the available CA techniques and provide an up-to-date optimum recommendation.

A systematic review and meta-analysis comparing second-generation cryoballoon and contact force radiofrequency ablation for initial ablation of paroxysmal and persistent atrial fibrillation

INTRODUCTION

Cryoballoon ablation (CBA) and radiofrequency ablation (RFA) are the preferred modalities for catheter ablation of atrial fibrillation (AF). Technological advances have improved procedural outcomes, warranting an updated comparison. We sought to evaluate the efficacy and safety of CBA-2nd generation (CBA-2G) in comparison to RFA-contact force (RFA-CF) in patients with AF.

METHODS

MEDLINE, Cochrane, and ClinicalTrials.gov databases were searched until 03/01/2020 for relevant studies comparing CBA-2G versus RFA-CF in patients undergoing initial catheter ablation for AF.

RESULTS

A total of 17 studies, involving 11 793 patients were included. There was no difference between the two groups in the outcomes of freedom from atrial arrhythmia (p = .67) and total procedural complications (p = .65). There was a higher incidence of phrenic nerve palsy in CBA-2G (odds ratio: 10.7; 95% confidence interval [CI]: 5.85 to 19.55; p < .001). Procedure duration was shorter (mean difference: -31.32 min; 95% CI: -40.73 to -21.92; p < .001) and fluoroscopy duration was longer (+3.21 min; 95% CI: 1.09 to 5.33; p = .003) in CBA-2G compared to RFA-CF. In the subgroup analyses of patients with persistent AF and >1 freeze lesion delivered per vein, there was no difference in freedom from atrial arrhythmia.

CONCLUSIONS

In AF patients undergoing initial ablation, CBA-2G and RFA-CF were equally efficacious. The procedure duration was shorter, but with a higher incidence of phrenic nerve palsy in CBA-2G. In patients with persistent AF, there was no difference in the efficacy between CBA-2G or RFA-CF techniques.

Strategies to Improve the Outcome of Cryoballoon Ablation in the Treatment of Atrial Fibrillation

Atrial fibrillation (AF) is a common arrhythmia contributing to severe outcomes, including cardiac dysfunction and stroke, and it has drawn great attention around the world. Drug therapies have been available for many years to terminate AF and control heart rate. However, the results from clinical studies on drug therapies have been discouraging. Mounting evidence indicates that radiofrequency catheter ablation (RFCA) is a safe and effective method to maintain sinus rhythm, especially in patients who are drug intolerant or for whom the drugs are ineffective, although it is a technically demanding and complex procedure. Fortunately, a novel application, cryoballoon ablation (CBA), with outstanding characteristics has been widely used. Great outcomes based on CBA have manifested its significant role in the treatment of AF. However, how to improve the safety and efficacy of CBA is a question that has not been well-answered. Would it be helpful to develop a different generation of cryoballoon? Is bonus freezing beneficial, or not? Is it better to prolong freezing time? Dose CBA combined with RFCA bring higher success rates? In this review, we comprehensively summarized useful applications for improving outcomes of CBA in AF patients.

Treatment of Atrial Fibrillation Using Ablation Index-Guided Contact Force Ablation: A Matching-Adjusted Indirect Comparison to Cryoballoon Ablation

Introduction

Ablation Index, also known as VISITAG SURPOINT™, is a novel lesion-quality marker that improves outcomes in radiofrequency (RF) catheter ablation of atrial fibrillation (AF). There is no direct evidence on the comparative effectiveness of RF ablation with Ablation Index and cryoballoon (CB). The objective of the present study was to conduct a matching-adjusted indirect comparison (MAIC) using individual patient-level data (IPD) to compare the effectiveness of RF ablation with Ablation Index to that of CB on recurrence of atrial arrhythmias 12 months after catheter ablation in patients with paroxysmal AF (PAF).

Methods

Individual patient-level data for RF ablation with Ablation Index were obtained from two studies: Solimene et al. [J Interv Card Electrophysiol 54(1):9–15, 2019] and Hussein et al. [J Cardiovasc Electrophysiol 28(9):1037–1047, 2017]. Comparable CB studies identified from a systematic literature review were pooled. Prognostic variables for adjustment were ranked a priori by several practicing electrophysiologists. In the absence of a common treatment arm between the Ablation Index and CB studies, an unanchored MAIC was conducted. Primary analysis compared the Solimene et al. study to pooled CB studies. A secondary analysis compared pooled RF ablation with Ablation Index studies to pooled CB studies. Several scenario and sensitivity analyses were conducted.

Results

Primary analyses showed statistically significant reductions in the rate of arrhythmia recurrence with RF ablation with Ablation Index compared to CB in unmatched, unadjusted (HR 0.50, 95% CI 0.27–0.95) and matched (0.42, 0.21–0.86) analyses. Greater reductions in the rate of arrhythmia recurrence that favored RF ablation with Ablation Index were observed after matching and adjusting for age (0.41, 0.20–0.85), age and left ventricular ejection fraction (0.37, 0.16–0.88), and age, sex, and left ventricular ejection fraction (0.30, 0.13–0.71). Secondary and sensitivity analyses showed similar reductions.

Conclusions

Radiofrequency ablation with Ablation Index was associated with reductions in recurrence of atrial arrhythmias at 12 months compared to CB in unmatched and unadjusted, matched, and matched and adjusted comparisons.

Electronic Supplementary Material

The online version of this article (10.1007/s12325-019-01173-4) contains supplementary material, which is available to authorized users.