Atrial fibrillation in heart failure: Prime time for ablation!

Surgical options for atrial fibrillation treatment during concomitant cardiac procedures

Current guidelines recommend concomitant surgical ablation (SA) of atrial fibrillation (AF) in the context of mitral valve disease. A variety of energy sources have been tested for SA to perform effective transmural lesions reliably. To date, only radiofrequency and cryothermy energies are considered viable options. The gold standard for SA is the Cox-Maze ablation set, especially for non-paroxysmal AF (nPAF), with the aim of interrupting macro-reentrant drivers perpetuating AF, without hampering the sinus node activation of both atria, and to maintain the atrioventricular synchrony. Although the efficacy of SA in terms of early and late sinus rhythm restoration has been clearly demonstrated over the years, concomitant AF ablation is still underperformed in patients with AF undergoing cardiac surgery. From a surgical standpoint, concerns have been raised about whether a single (left) or double atriotomy would be justified in AF patients undergoing a "non-atriotomy" surgical procedure, such as aortic valve or revascularization surgery. Thus, an array of simplified lesion sets have been described in the last decade, which have unavoidably hampered procedural efficacy, somewhat jeopardizing the standardization process of ablation surgery. As a matter of fact, the term "Maze" has improperly become a generic term for SA. Surgical interventions that do not align with the principles of forming conduction-blocking lesions according to the Maze pattern, cannot be classified as Maze procedures. In this complex scenario, a tailored approach according to the different AF patterns has been proposed: for patients with concomitant nPAF, a biatrial Cox-Maze ablation is recommended. Conversely, it might be reasonable to limit lesions to the left atrium or the pulmonary veins in patients with paroxysmal AF (PAF) in some clinical scenarios. The aim of this review is to provide an overview of the current ablation strategies for patients with AF undergoing concomitant cardiac surgery.

Efficacy of Early Catheter Ablation for Atrial Fibrillation After Admission for Heart Failure

BACKGROUND

Advances in catheter ablation (CA) for atrial fibrillation (AF) have improved the prognosis of patients with heart failure (HF) and AF. However, its optimal timing remains to be fully elucidated.

OBJECTIVES

The aim of this study was to investigate the prognostic impact of early CA in patients with HF and AF hospitalized for worsening HF.

METHODS

From JROADHF (Japanese Registry of Acute Decompensated Heart Failure) (n = 13,238), patients with HF and AF who underwent CA within 90 days after admission for HF (early CA; n = 103) and those who did not (control; n = 2,683) were identified. Mortality was compared between these groups in the crude cohort, as well as in the propensity-matched cohort (n = 83 in each group).

RESULTS

In the crude cohort, all-cause mortality was significantly lower in the early CA group than in the control group (log-rank P < 0.001; HR: 0.38; 95% CI: 0.24-0.60). In the matched cohort, all-cause mortality was likewise significantly lower in the early CA group (log-rank P = 0.014; HR: 0.47; 95% CI: 0.25-0.88). Cardiovascular death and HF mortality were significantly lower in both cohorts (crude: Gray' test: P < 0.001 and P = 0.005; subdistribution HR: 0.28 [95% CI: 0.13-0.63] and HR: 0.31 [95% CI: 0.13-0.75]; matched: Gray's test: P = 0.006 and P = 0.017; subdistribution HR: 0.24 [95% CI: 0.08-0.70] and HR: 0.28 [95% CI: 0.09-0.84], respectively).

CONCLUSIONS

In a nationwide representative real-world cohort, CA for AF within 90 days after admission for HF was associated with improved long-term outcomes, including cardiovascular and HF death in patients with HF and AF.

Catheter ablation improves cardiovascular outcomes in patients with atrial fibrillation and heart failure: a meta-analysis of randomized controlled trials

AIMS

The effect of atrial fibrillation catheter ablation on cardiovascular outcomes in heart failure is an important outstanding research question. We undertook a meta-analysis of randomized controlled trials comparing ablation to medical therapy in patients with AF and heart failure.

METHODS AND RESULTS

We systematically identified all trials comparing catheter ablation to medical therapy in patients with heart failure and atrial fibrillation. The pre-specified primary endpoint was all-cause mortality in trials with at least 2 years of follow-up. The secondary endpoint was heart failure hospitalization. Sensitivity analyses were performed for trials with any follow-up and trials deemed at low risk of bias. Eight trials (1390 patients) were included. Seven hundred and seven patients were randomized to catheter ablation and 683 to medical therapy. In the primary analysis (three trials, n = 977), catheter ablation reduced mortality compared with medical therapy [relative risk (RR): 0.61, 95% confidence interval (CI): 0.44 to 0.84, P = 0.003]. Catheter ablation also reduced heart failure hospitalizations compared with medical therapy (RR: 0.60, 95% CI: 0.49-0.74, P < 0.001). The effect on stroke was not statistically significant (RR: 0.62, 95% CI: 0.28-1.37, P = 0.237). There was low heterogeneity between studies. Sensitivity analyses were consistent with the primary analyses.

CONCLUSION

In patients with atrial fibrillation and heart failure, catheter ablation reduces mortality and the occurrence of heart failure hospitalizations.

Catheter ablation of atrial fibrillation in heart failure with impaired systolic function: An updated meta-analysis of randomized controlled trials

BACKGROUND

The recent Atrial Fibrillation Management in Congestive Heart Failure With Ablation trial did not reveal any benefit of catheter ablation in patients with atrial fibrillation (AF), advanced heart failure (HF), and severely reduced left ventricular ejection fraction (LVEF). We hypothesized that radiofrequency catheter ablation (RFCA) could improve outcomes in HF patients with AF and impaired left ventricular systolic function (LVEF <50%) as compared with only medical therapy.

METHODS

We searched the literature for randomized clinical trials (RCTs) that compared RFCA to medical therapy in this population.

RESULTS

Compared with the medical therapy group, the RFCA group had significantly less all-cause mortality, HF hospitalization, and AF recurrence rates. The RFCA group had significantly higher peak oxygen consumption (VO 2max ), a better quality of life (Minnesota Living with Heart Failure Questionnaire score), and improved LVEF. However, RFCA for AF failed to reduce all-cause mortality in a specific meta-analysis of four RCTs that enrolled patients with LVEF ≤35%.

CONCLUSION

Compared with medical therapy, RFCA for AF in the setting of HF with impaired systolic function is associated with better clinical (HF hospitalization and all-cause mortality), structural (LVEF improvement), functional (VO 2max ), and quality of life outcomes. However, RFCA for AF failed to reduce all-cause mortality in RCTs that enrolled patients with LVEF ≤35% and thereby indicated the necessary stratification to identify patients who may benefit more from RFCA.

Catheter Ablation for Patients with Atrial Fibrillation and Heart Failure: Insights from the Swedish Heart Failure Registry

AIMS

To investigate the association between catheter ablation for atrial fibrillation (AF) and mortality as well as hospitalization for heart failure (HF) in patients with HF across the ejection fraction (EF) spectrum.

METHODS

Patients with first-time catheter ablation for AF (ablation group) compared to only medical treated AF patients (no ablation group) were identified from the Swedish Heart Failure Registry between 2005 and 2019. The primary outcome (all-cause mortality/first HF hospitalization) was assessed by Cox regression models in a 1:2 propensity score (PS) matched cohort and pre-specified EF subgroups (preserved EF [HFpEF] [EF≥50%], mildly reduced EF [HFmrEF] [EF 40% to 49%], reduced EF [HFrEF] [EF<40%]) of this cohort.

RESULTS

452 patients in the ablation and 43766 patients in the no ablation group were identified. After PS matching, 434 patients in the ablation group were compared to 868 patients in the no ablation group. Over a median follow-up of 2.6 years (min. 0.0 years - max. 14.1 years), catheter ablation was associated with a lower risk of the primary outcome (all-cause mortality/first HF hospitalization) (Hazard ratio [HR] 0.78 [95%CI,0.65-0.94]). Results were consistent across all EF subgroups. In HFpEF, catheter ablation was also associated with a lower risk of recurrent HF hospitalization (Incidence rate ratio [IRR] 0.17 [95%CI,0.07-0.42]).

CONCLUSION

In HF patients across the EF spectrum, catheter ablation for AF was associated with lower risk of the primary outcome (all-cause mortality/first HF hospitalization). This study supports catheter ablation as a treatment option for AF in HF patients, including those with HFpEF. This article is protected by copyright. All rights reserved.