Cryoballoon catheter ablation or drug therapy to delay progression of atrial fibrillation: A single-center randomized trial

Catheter ablation for atrial fibrillation and impact on clinical outcomes

Aims

Catheter ablation is the most effective rhythm-control option in patients with atrial fibrillation (AF) and is currently considered an option mainly for improving symptoms. We aimed to assess the impact of catheter ablation on hard clinical outcomes.

Methods and results

We performed a systematic review of randomized controlled trials (RCTs) comparing catheter ablation vs. optimized medical treatment. We searched MEDLINE, EMBASE, and CENTRAL on 8 January 2024, for trials published ≤10 years. We pooled data through risk ratio (RR) and mean differences (MDs), with 95% confidence interval (CI), and calculated the number needed to treat (NNT). Sub-group and sensitivity analyses were performed for the presence/absence of heart failure (HF), paroxysmal/persistent AF, early ablation, higher/lower quality, and published ≤5 vs. >5 years. Twenty-two RCTs were identified, including 6400 patients followed for 6-52 months. All primary endpoints were significantly reduced by catheter ablation vs. medical management: all-cause hospitalization (RR = 0.57, 95% CI 0.39-0.85, P = 0.006), AF relapse (RR = 0.48, 95% CI 0.39-0.58, P < 0.00001), and all-cause mortality (RR = 0.69, 95% CI 0.56-0.86, P = 0.0007, NNT = 44.7, driven by trials with HF patients). A benefit was also demonstrated for all secondary endpoints: cardiovascular mortality (RR = 0.55, 95% CI 0.34-0.87), cardiovascular (RR = 0.83, 95% CI 0.71-0.96), and HF hospitalizations (RR = 0.71, 95% CI 0.56-0.89), AF burden (MD = 20.6%, 95% CI 5.6-35.5), left ventricular ejection fraction (LVEF) recovery (MD = 5.7%, 95% CI 3.5-7.9), and quality of life (MLHFQ, AFEQT, and SF-36 scales).

Conclusion

Catheter ablation significantly reduced hospitalizations, AF burden, and relapse, and improved quality of life. An impact on hard clinical outcomes, with an important mortality reduction and improvement in LVEF, was seen for patients with AF and HF.

Atrial fibrillation progression after cryoablation vs. radiofrequency ablation: the CIRCA-DOSE trial

BACKGROUND AND AIMS

Atrial fibrillation (AF) is a chronic progressive disorder. Persistent forms of AF are associated with increased rates of thromboembolism, heart failure, and death. Catheter ablation modifies the pathogenic mechanism of AF progression. No randomized studies have evaluated the impact of the ablation energy on progression to persistent atrial tachyarrhythmia.

METHODS

Three hundred forty-six patients with drug-refractory paroxysmal AF were enrolled and randomly assigned to contact-force-guided RF ablation (CF-RF ablation, 115), 4 min cryoballoon ablation (CRYO-4, 115), or 2 min cryoballoon ablation (CRYO-2, 116). Implantable cardiac monitors placed at study entry were used for follow-up. The main outcome was the first episode of persistent atrial tachyarrhythmia. Secondary outcomes included atrial tachyarrhythmia recurrence and arrhythmia burden on the implantable monitor.

RESULTS

At a median of 944.0 (interquartile range [IQR], 612.5-1104) days, 0 of 115 patients (0.0%) randomly assigned to CF-RF, 8 of 115 patients (7.0%) assigned to CRYO-4, and 5 of 116 patients (4.3%) assigned to CRYO-2 experienced an episode of persistent atrial tachyarrhythmia (P = .03). A documented recurrence of any atrial tachyarrhythmia ≥30 s occurred in 56.5%, 53.9%, and 62.9% of those randomized to CF-RF, CRYO-4, and CRYO-2, respectively; P = .65. Compared with that of the pre-ablation monitoring period, AF burden was reduced by a median of 99.5% (IQR 94.0%, 100.0%) with CF-RF, 99.9% (IQR 93.3%-100.0%) with CRYO-4, and 99.1%% (IQR 87.0%-100.0%) with CRYO-2 (P = .38).

CONCLUSIONS

Catheter ablation of paroxysmal AF using radiofrequency energy was associated with fewer patients developing persistent AF on follow-up.

Quality of Life and Safety Outcomes after First-Line Treatment of Symptomatic AF with Cryoablation or Drug Therapy: A Meta-Analysis of Randomized Controlled Trials

Background

Cryoablation has emerged as a recognized interventional strategy for the treatment of atrial fibrillation (AF). Numerous trials have investigated cryoablation as a first-line therapy for AF. This meta-analysis aimed to evaluate the impact of cryoablation on quality of life (QoL) and safety outcomes compared to antiarrhythmic drugs (AADs) in patients with symptomatic AF.

Methods

A comprehensive search of the PubMed, EMBASE, and Cochrane Library databases was conducted for randomized controlled trials (RCTs) comparing cryoablation and AADs as first-line treatments for AF until May 2023. Continuous outcome data were analyzed using mean differences (MDs) with 95% confidence intervals (CIs), and dichotomous outcome data were analyzed using relative risks (RRs) with 95% CIs. The primary outcomes assessed were QoL and serious adverse events.

Results

Our analysis included four RCTs involving 928 patients. Cryoablation was associated with a significant improvement in the AF Effect on Quality of Life (AFEQT) score (3 trials; MD 7.46, 95% CI 2.50 to 12.42; p = 0.003; I 2 = 79%) and EQ-VAS score (2 trials; MD 1.49, 95% CI 1.13 to 1.86; p < 0.001; I 2 = 0%) compared to AAD therapy. Additionally, cryoablation demonstrated a modest increase in EQ-5D score from baseline compared to AAD therapy, with no statistically significance (2 trials; MD 0.03, 95% CI -0.01 to 0.07; p = 0.07; I 2 = 79%). Furthermore, the rate of serious adverse events was significantly lower with cryoablation compared to AAD therapy (4 trials; 11.8% vs. 16.3%; RR, 0.73; 95% CI, 0.54-1.00; p = 0.05; I 2 = 0%). Cryoablation was also associated with a reduction in overall adverse events, incidence of persistent AF, hospitalizations, and additional ablation. However, there was no significant difference in major adverse cardiovascular events and emergency department visits between the two treatment groups.

Conclusions

Cryoablation, as a first-line treatment for symptomatic AF patients, significantly improved AF-specific quality of life and reduced serious adverse events, as well as overall adverse events, persistent AF, hospitalizations, and additional ablation compared to AADs.

Catheter ablation in patients with paroxysmal atrial fibrillation and absence of structural heart disease: A meta-analysis of randomized trials

Introduction

Rhythm control strategy in paroxysmal atrial fibrillation (AF) can be performed with antiarrhythmic drugs (AAD) or catheter ablation (CA). Nevertheless, a clear overview of the percentage of freedom from AF over time and complications is lacking. Therefore, we conducted a meta-analysis of randomized controlled trials (RCTs) comparing CA versus AAD.

Methods

We searched databases up to 5 May 2023 for RCTs focusing on CA versus AAD. The study endpoints were atrial tachyarrhythmia (AT) recurrence, progression to persistent AF, overall complications, stroke/TIA, bleedings, heart failure (HF) hospitalization and all-cause mortality.

Results

Twelve RCTs enrolling 2393 patients were included. CA showed a significantly lower AT recurrence rate at one year [27.4 % vs 56.3 %; RR: 0.45; p < 0.00001], at two years [39.9 % vs 62.7 %; RR: 0.56; p = 0.0004] and at three years [45.7 % vs 80.9 %; RR: 0.54; p < 0.0001] compared to AAD. Furthermore, CA significantly reduced the progression to persistent AF [1.6 % vs 12.9 %; RR: 0.14; p < 0.00001] with no differences in overall complications [5.9 % vs 4.5 %; RR: 1.27; p = 0.22], stroke/TIA [0.6 % vs 0.6 %; RR: 1.10; p = 0.86], bleedings [0.4 % vs 0.6 %; RR: 0.90; p = 0.84], HF hospitalization [0,3% vs 0,7%; RR: 0.56; p = 0.37] and all-cause mortality [0,4% vs 0.5 %; RR: 0.78; p = 0.67]. Subgroup analysis between radiofrequency and cryo-ablation or considering RCTs with CA as first-line treatment showed no significant differences.

Conclusion

CA demonstrated lower rates of AT recurrence over the time, as well as a significant reduction in the progression from paroxysmal to persistent AF, with no difference in terms of energy source, complications, and clinical outcomes.

Short-term and long-term effects of cryoballoon ablation versus antiarrhythmic drug therapy as first-line treatment for paroxysmal atrial fibrillation: A systematic review and meta-analysis

Cryoballoon ablation (CBA) is an effective treatment for drug-refractory atrial fibrillation (AF) patients. Whether CBA as a first-line treatment is superior in the rhythm control of AF than antiarrhythmic drugs (AAD) remains unclear. CBA is superior to AAD as initial therapy for rhythm control of paroxysmal atrial fibrillation (PAF). A comprehensive database search was performed in PubMed, Embase, Cochrane, and Web of Science from inception to March 22, 2023. Treatment efficacy was pooled using risk ratio (RR) and standardized mean difference (SMD) with a 95% confidence interval (CI). This study was registered with Prospero (CRD42023401596). Five randomized-controlled trials involving 923 patients and an observational study were included in this study. The CBA group had a significantly lower overall recurrence rate than the AAD group (CBA vs. AAD: RR = 0.59, 95% CI = 0.49-0.71, p < .05, I2  = 0). The incidence of persistent AF could be better controlled in the CBA group than in the AAD (CBA vs. AAD: RR = 0.17, 95% CI = 0.06-0.49, p < .05, I2  = 0). CBA could improve the quality of life (QoL) of patients better than AAD (CBA vs. AAD: SMD = 0.40, 95% CI = 0.14-0.67, p < .05, I2  = 68.5%). CBA can reduce hospitalization rate significantly than AAD at 36-month follow-up (CBA vs. AAD: RR = 0.29, 95% CI = 0.15-0.58, p < .05, I2  = 0%). Compared to AAD, CBA as first-line therapy could reduce the recurrence rate of atrial arrhythmia and incidence of persistent AF and improve QoL in PAF patients with lower incidences of hospitalization.