Comparison between surgical and catheter based ablation in atrial fibrillation, should surgical based ablation be implemented as first line? - A meta-analysis of studies

Efficacy and safety of different forms of ablation therapies and antiarrhythmic drugs in atrial fibrillation: a systematic review and network meta-analysis of randomized clinical trials

Background

This Bayesian network meta-analysis (NMA) was conducted to compare the efficacy and safety of ablations and antiarrhythmic drugs (AADs) to determine the optimal treatment choice for atrial fibrillation (AF).

Methods

We searched PubMed, Embase, Web of Science, and Cochrane Library from their inception to December 15, 2024, for relevant randomized controlled trials (RCTs). The risk of bias assessment tool developed by the Cochrane Collaboration Network was utilized to evaluate the risk of bias. The main outcomes were AF recurrence, adverse events, and all-cause death. A Bayesian NMA was conducted based on the collected data.

Results

In total, 65 RCTs (n=17,770) comparing four ablations [cryoablation (CBA), laser balloon ablation (LBA), radiofrequency ablation (RFA), surgical ablation (SA)] and AADs were included. In this NMA, the four ablations all significantly reduced the risk of recurrent AF compared with AADs, with no significant differences [RFA: risk ratio (RR) =0.503, 95% confidence interval (CI): 0.423-0.594; CBA: RR =0.465, 95% CI: 0.370-0.579; LBA: RR =0.522, 95% CI: 0.306-0.891; SA: RR =0.664, 95% CI: 0.392-1.12]. CBA and SA groups may be associated with more adverse events than AAD groups (CBA: RR =1.462, 95% CI: 0.956-2.283; SA: RR =2.054, 95% CI: 0.999-4.369). RFA appeared to reduce all-cause mortality compared to AADs (RR =0.745, 95% CI: 0.552-1.014). CBA took the shortest time to complete compared to the other three ablations.

Conclusions

Catheter ablation (CA) and SA are equally effective and superior to AADs. However, SA has a high risk of complications, while compared with AADs, no evidence indicates that RFA and SA significantly reduce the risk of mortality.

Mid-to-long-term recurrence of atrial fibrillation in surgical treatment vs. catheter ablation: a meta-analysis using aggregated survival data

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia and leading cardiac cause of stroke. Catheter and surgical ablation are two techniques used currently to resolve prolonged disease by limiting the excitatory potential of specific areas of myocardium in the atria of the heart. The aim of this systematic review and meta-analysis was to provide a graphical amalgamation of mid-to-long-term rhythm outcomes following transcatheter and surgical intervention, whether primary or concomitant ablation.

Methods

Three electronic databases were selected to complete the initial literature search from inception of records until April 2023. Primary outcomes were freedom from AF at 12 months, as well as long term time-to-event recurrence data. These data were calculated using aggregated Kaplan-Meier curves according to established methods. The secondary outcome was procedural time for each ablation method.

Results

Following independent screening, 36 studies were included for analysis. A total of 6,700 patients were followed, of whom 4,863 (72.6%) were male. Freedom from AF recurrence at 1, 3 and 5 years for the surgical cohort was 71.7%, 57.6% and 47.6%, respectively. Comparatively, the recurrence rates of the catheter ablation cohort at 1, 3 and 5 years were 71.5%, 56.5% and 50.3%, respectively.

Conclusions

Despite potentially more complex diseases, surgical ablation patients have non-inferior long-term AF recurrence when compared to those undergoing catheter ablation. Recurrence at 12 months as well as procedural time are also similar between these groups. Ultimately, both ablation methods were able to prevent recurrence of AF in approximately 50% of patients at five years following the procedure.

Ablative Management of Persistent Atrial Fibrillation (PeAF) with Posterior Wall Isolation (PWI): Where Do We Stand?

Atrial fibrillation is a diverse clinical entity, with persistent atrial fibrillation (PeAF) being particularly challenging to manage. Through this paper, we discuss notable developments in our understanding of ablative strategies for managing PeAF, with a special focus on posterior wall isolation (PWI).

Atrial fibrillation: Primary prevention, secondary prevention, and prevention of thromboembolic complications: Part 2

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia, once thought to be benign as long as the ventricular rate was controlled, is associated with significant cardiac morbidity and mortality. Increasing life expectancy driven by improved health care and decreased fertility rates has, in most of the world, resulted in the population aged ≥65 years growing more rapidly than the overall population. As the population ages, projections suggest that the burden of AF may increase more than 60% by 2050. Although considerable progress has been made in the treatment and management of AF, primary prevention, secondary prevention, and prevention of thromboembolic complications remain a work in progress. This narrative review was facilitated by a search of MEDLINE to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, and other clinically relevant studies. The search was limited to English-language reports published between 1950 and 2021. Atrial fibrillation was searched using the terms primary prevention, hyperthyroidism, Wolff-Parkinson-White syndrome, catheter ablation, surgical ablation, hybrid ablation, stroke prevention, anticoagulation, left atrial occlusion and atrial excision. Google and Google scholar as well as bibliographies of identified articles were reviewed for additional references. In these two manuscripts, we discuss the current strategies available to prevent AF, then compare non-invasive and invasive treatment strategies to diminish AF recurrence. In addition, we examine the pharmacological, percutaneous device and surgical approaches to prevent stroke as well as other types of thromboembolic events.

Catheter contact area strongly correlates with lesion area in radiofrequency cardiac ablation: an ex vivo porcine heart study

PURPOSE

Our previous study confirmed that not only force but also the catheter contact angle substantially impacted the contact area and its morphology. Therefore, in this study, we aimed to further investigate the relationship between the catheter contact area and the dimensions of the ablation lesion area as a function of catheter contact angle and force in radiofrequency catheter ablation.

METHODS

The radiofrequency catheter ablation test was performed for 5 contact angles and 8 contact forces at a fixed ablation time of 30 s. The initial impedance was 92.5 ± 2.5 Ω, the temperature during ablation was 30 °C, and the power was 30 W. The irrigation rate during ablation was set to 17 mL/min. Each experiment was repeated 6 times.

RESULTS

The catheter contact area showed a strong correlation with the ablation lesion area (r = 0.8507). When the contact area was increased, the lesion area also increased linearly in a monotonic manner. The relationships between catheter contact force and ablation lesion area and between catheter contact force and ablation lesion depth are logarithmic functions in which increased contact force was associated with increased lesion area and depth. The catheter contact angle is also an important determinant of the lesion area. The lesion area progressively increased when the contact angle was decreased. In contrast, the lesion depth progressively increased when the contact angle was increased.

CONCLUSIONS

The catheter contact area was strongly correlated with the ablation lesion area. Additionally, catheter contact force and contact angle significantly impacted the dimensions of the lesion in radiofrequency catheter ablation procedures.

BMI and atrial fibrillation recurrence post catheter ablation: A dose-response meta-analysis

INTRODUCTION

The evidence on the association between obesity and atrial fibrillation (AF) recurrence was equivocal. We aimed to evaluate the dose-response relationship between body mass index (BMI) and AF recurrence and adverse events.

METHODS

A systematic literature search was conducted using PubMed, Europe PMC, EBSCO, ProQuest and Cochrane Library. Obesity was defined as BMI ≥28 kg/m2 . The primary outcome was AF recurrence, and the secondary outcome was adverse events. Adverse events were defined as procedure-related complications and cardio-cerebrovascular events.

RESULTS

There were a total of 52,771 patients from 20 studies. Obesity was associated with higher AF recurrence (Odds ratio [OR] 1.30 [95% confidence interval [CI] 1.16-1.47], P < .001; I2 : 72.7%) and similar rate of adverse events (OR 1.21 [95% CI 0.87-1.67], P = .264; I2 : 23.9%). Meta-regression showed that the association varies by age (coefficient: -0.03, P = .024). Meta-analysis of highest versus lowest BMI showed that the highest group had higher AF recurrence (OR 1.37 [95% CI 1.18-1.58], P < .001; I2 : 64.9%) and adverse events (OR 2.02 [95% CI 1.08-3.76], P = .028; I2 : 49.5%). The linear association analysis for AF recurrence was not significant (P = .544). The dose-response relationship for BMI and AF recurrence was nonlinear (pnonlinearity  < 0.001), the curve became steeper at 30-35 kg/m2 . For adverse events, an increase of 1% for every 1 kg/m2 increase in BMI (OR 1.01 [95% CI 1.00-1.02], P = .001), the relationship was nonlinear (pnonlinearity  = 0.001).

CONCLUSION

Obesity was associated with higher AF recurrence in patients undergoing catheter ablation. High BMI might be associated with a higher risk for adverse events.

PROSPERO ID

CRD42020198787.

Relationship of Catheter Contact Angle and Contact Force with Contact Area on the Surface of Heart Muscle Tissue in Cardiac Catheter Ablation

Purpose

The aims of this study were to develop an experimental procedure for setting the catheter angle with respect to the surface of the heart muscle and the catheter contact force and to investigate the catheter contact area on the heart muscle as a function of catheter contact angle and force.

Methods

Visualization tests were performed for 5 contact angles (0°, 30°, 45°, 60°, and 90°) and 8 contact forces (2, 4, 6, 10, 15, 20, 30, and 40 gf). Each experiment was repeated 6 times with 2 different commercially available catheter tips.

Results

The morphology of the contact area was classified into rectangular, circular, ellipsoidal, and semi-ellipsoidal. The correlation between contact force and contact area was a logarithmic function; increasing contact force was associated with increased contact area. At the same contact force, the correlation between contact angle and contact area was inverse; decreasing contact angle was associated with a corresponding increase in contact area.

Conclusion

Both the catheter contact angle and contact force substantially impact the contact area and morphology in catheter ablation procedures.