Efficacy and safety of dronedarone by atrial fibrillation history duration: Insights from the ATHENA study

Rhythm versus rate control in patients with newly diagnosed atrial fibrillation - Observations from the GARFIELD-AF registry

Background

Investigate real-world outcomes of early rhythm versus rate control in patients with recent onset atrial fibrillation.

Methods

The Global Anticoagulant Registry in the FIELD-AF (GARFIELD-AF) is an international multi-centre, non-interventional prospective registry of newly diagnosed (≤6 weeks' duration) atrial fibrillation patients at risk for stroke. Patients were stratified according to treatment initiated at baseline (≤48 days post enrolment), and outcome risks evaluated by overlap propensity weighted Cox proportional-hazards models.

Results

Of 45,382 non-permanent atrial fibrillation patients, 23,858 (52.6 %) received rhythm control and 21,524 (47.4 %) rate control. Rhythm-controlled patients had lower median age (68.0 [Q1;Q3: 60.0;76.0] versus 73.0 [65.0;79.0]), fewer histories of stroke/transient ischemic attack/systemic embolism (9.4 % versus 13.0 %), and lower expected probabilities of death (median GARFIELD-AF death score 4.0 [2.3;7.5] versus 5.1 [2.8;9.2]). The two groups had the same median CHA2DS2-VASc scores (3.0 [2.0;4.0]) and similar proportions of anticoagulated patients (rhythm control: 66.0 %, rate control: 65.5 %). The propensity-score-weighted hazard ratios of rhythm vs rate control (reference) were 0.85 (95 % CI: 0.79-0.92, p-value < 0.0001) for all-cause mortality, 0.84 (0.72-0.97, p-value 0.020) for non-haemorrhagic stroke/systemic embolism and 0.90 (0.78-1.04, p-value 0.164) for major bleeding.

Conclusion

Rhythm control strategy was initiated in about half of the patients with newly diagnosed non-valvular non-permanent atrial fibrillation. After balancing confounders, significantly lower risks of all-cause mortality and non-haemorrhagic stroke were observed in patients who received early rhythm control.

Effect of dronedarone vs. placebo on atrial fibrillation progression: a post hoc analysis from ATHENA trial

AIMS

This post hoc analysis of the ATHENA trial (NCT00174785) assessed the effect of dronedarone on the estimated burden of atrial fibrillation (AF)/atrial flutter (AFL) progression to presumed permanent AF/AFL, and regression to sinus rhythm (SR), compared with placebo.

METHODS AND RESULTS

The burden of AF/AFL was estimated by a modified Rosendaal method using available electrocardiograms (ECG). Cumulative incidence of permanent AF/AFL (defined as ≥6 months of AF/AFL until end of study) or permanent SR (defined as ≥6 months of SR until end of study) were calculated using Kaplan-Meier estimates. A log-rank test was used to assess statistical significance. Hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were estimated using a Cox model, adjusted for treatment group. Of the 4439 patients included in this analysis, 2208 received dronedarone, and 2231 placebo. Baseline and clinical characteristics were well balanced between groups. Overall, 304 (13.8%) dronedarone-treated patients progressed to permanent AF/AFL compared with 455 (20.4%) treated with placebo (P < 0.0001). Compared with those receiving placebo, patients receiving dronedarone had a lower cumulative incidence of permanent AF/AFL (log-rank P < 0.001; HR: 0.65; 95% CI: 0.56-0.75), a higher cumulative incidence of permanent SR (log-rank P < 0.001; HR: 1.19; 95% CI: 1.09-1.29), and a lower estimated AF/AFL burden over time (P < 0.01 from Day 14 to Month 21).

CONCLUSION

These results suggest that dronedarone could be a useful antiarrhythmic drug for early rhythm control due to less AF/AFL progression and more regression to SR vs. placebo, potentially reflecting reverse remodeling.

CLINICAL TRIAL REGISTRATION

NCT00174785.

Effectiveness of early rhythm control in improving clinical outcomes in patients with atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

Current guidelines recommend rhythm control for improving symptoms and quality of life in symptomatic patients with atrial fibrillation (AF). However, the long-term prognostic outcomes of rhythm control compared with rate control are still inconclusive. In this meta-analysis, we aimed to assess the effects of early rhythm control compared with rate control on clinical outcomes in newly diagnosed AF patients.

METHODS

We systematically searched the PubMed and Embase databases up to August 2022 for randomized and observational studies reporting the associations of early rhythm control (defined as within 12 months of AF diagnosis) with effectiveness outcomes. The primary outcome was a composite of death, stroke, admission to hospital for heart failure (HF), or acute coronary syndrome (ACS). Hazard ratios (HRs) and 95% confidence intervals (CIs) from each study were pooled using a random-effects model, complemented with an inverse variance heterogeneity or quality effects model.

RESULTS

A total of 8 studies involving 447,202 AF patients were included, and 23.5% of participants underwent an early rhythm-control therapy. In the pooled analysis using the random-effects model, compared with rate control, the early rhythm-control strategy was significantly associated with reductions in the primary composite outcome (HR = 0.88, 95% CI: 0.86-0.89) and secondary outcomes, including stroke or systemic embolism (HR = 0.78, 95% CI: 0.71-0.85), ischemic stroke (HR = 0.81, 95% CI: 0.69-0.94), cardiovascular death (HR = 0.83, 95% CI: 0.70-0.99), HF hospitalization (HR = 0.90, 95% CI: 0.88-0.92), and ACS (HR = 0.86, 95% CI: 0.76-0.98). Reanalyses using the inverse variance heterogeneity or quality effects model yielded similar results.

CONCLUSIONS

Our current meta-analysis suggested that early initiation of rhythm control treatment was associated with improved adverse effectiveness outcomes in patients who had been diagnosed with AF within 1 year.

REGISTRATION

The study protocol was registered to PROSPERO (CRD42021295405).

Effect of Dronedarone in the Treatment of Atrial Fibrillation in the Asian Population: Post Hoc Analysis of the ATHENA Trial

PURPOSE

Limited data are available on the impact of dronedarone treatment in Asian patients with atrial fibrillation (AF) or atrial flutter (AFL). This post hoc analysis evaluated the efficacy and safety of dronedarone compared with placebo in populations from Asian and non-Asian regions randomized in the ATHENA trial (A Placebo-Controlled, Double-blind, Parallel Arm Trial to Assess the Efficacy of Dronedarone 400 mg BID for the Prevention of CV Hospitalization or Death From Any Cause in Patients With AF/AFL).

METHODS

Time to first hospitalization for cardiovascular events or death from any cause (primary outcome) and time to first AF/AFL event recurrence (secondary outcome) were analyzed by Kaplan-Meier curves and Cox proportional hazards regression.

FINDINGS

The risk of experiencing the primary composite outcome was significantly lower in the dronedarone-treated patients in both the Asian (hazard ratio = 0.541; 95% CI, 0.320-0.914]) and non-Asian (hazard ratio = 0.768; 95% CI, 0.696-0.848) populations than in the placebo-treated patients. The median time to the first AF/AFL event recurrence was longer in the dronedarone-treated population than in the placebo-treated populations: 183 vs 92 days (P = 0.165) in the Asian population and 534 vs 196 days (P < 0.001) in the non-Asian population. Treatment-emergent adverse events in Asian (81.2% vs 78.4%) and non-Asian (71.4% vs 68.7%) populations and serious treatment-emergent adverse events in Asian (14.3% vs 15.7%) and non-Asian (20.3% vs 21.5%) patients were comparable in patients taking dronedarone compared with those taking placebo.

IMPLICATION

Efficacy and tolerability of dronedarone were consistent in the Asian population compared with the non-Asian population in the ATHENA trial. These finding may aid Asian health care professionals to select the appropriate first-line treatment for Asian patients with AF/AFL.

The Increasing Role of Rhythm Control in Patients With Atrial Fibrillation: JACC State-of-the-Art Review

The considerable mortality and morbidity associated with atrial fibrillation (AF) pose a substantial burden on patients and health care services. Although the management of AF historically focused on decreasing AF recurrence, it evolved over time in favor of rate control. Recently, more emphasis has been placed on reducing adverse cardiovascular outcomes using rhythm control, generally by using safe and effective rhythm-control therapies (typically antiarrhythmic drugs and/or AF ablation). Evidence increasingly supports early rhythm control in patients with AF that has not become long-standing, but current clinical practice and guidelines do not yet fully reflect this change. Early rhythm control may effectively reduce irreversible atrial remodeling and prevent AF-related deaths, heart failure, and strokes in high-risk patients. It has the potential to halt progression and potentially save patients from years of symptomatic AF; therefore, it should be offered more widely.

Dronedarone for the Treatment of Atrial Fibrillation with Concomitant Heart Failure with Preserved and Mildly Reduced Ejection Fraction: Post-Hoc Analysis of the ATHENA Trial

AIMS

Limited therapeutic options are available for the management of atrial fibrillation/flutter (AF/AFL) with concomitant heart failure with preserved and mildly reduced ejection fraction. (HFpEF and HFmrEF). Dronedarone reduces the risk of cardiovascular events in patients with AF, but sparse data are available examining its role in patients with AF complicated by HFpEF and HFmrEF.

METHODS AND RESULTS

ATHENA was an international, multicenter trial that randomized 4,628 patients with paroxysmal or persistent AF/AFL and cardiovascular risk factors to dronedarone 400 mg twice daily versus placebo. We evaluated patients with 1) symptomatic HFpEF and HFmrEF (defined as LVEF>40%, evidence of structural heart disease, and New York Heart Association class II/III or diuretic use), 2) HF with reduced ejection fraction (HFrEF) or left ventricular dysfunction (LVEF≤40%), and 3) those without HF. We assessed effects of dronedarone vs placebo on death or cardiovascular hospitalization (primary endpoint), other key efficacy endpoints, and safety. Overall, 534 (12%) had HFpEF or HFmrEF, 422 (9%) had HFrEF or LV dysfunction, and 3,672 (79%) did not have HF. Patients with HFpEF and HFmrEF had a mean age of 73±9 years, 37% were women, and had a mean LVEF of 57±9%. Over 21±5 months mean follow-up, dronedarone consistently reduced risk of death or cardiovascular hospitalization (hazard ratio 0.76; 95% confidence interval 0.69-0.84) without heterogeneity based on HF status (P_interaction >0.10). This risk reduction in the primary endpoint was consistent across the range of LVEF (as a continuous function) in HF without heterogeneity (P_interaction =0.71). Rates of death, cardiovascular hospitalization, and HF hospitalization each directionally favored dronedarone vs. placebo in HFpEF and HFmrEF, but these treatment effects were not statistically significant.

CONCLUSIONS

Dronedarone is associated with reduced cardiovascular events in patients with paroxysmal or persistent AF/AFL and HF across the spectrum of LVEF, including among those with HFpEF and HFmrEF. These data support a rationale for a future dedicated and powered clinical trial to affirm the net clinical benefit of dronedarone in this population.

Healthcare resource utilization in patients with newly diagnosed atrial fibrillation in the United States

OBJECTIVES

To summarize healthcare resource utilization (HCRU) in patients with newly diagnosed (incident) paroxysmal or persistent atrial fibrillation (AF).

METHODS

This retrospective, observational cohort study assessed HCRU among patients with incident paroxysmal or persistent AF using data from 1 January 2015 to 30 September 2019 in the IBM MarketScan® Research Databases.

RESULTS

A total of 50,796 patients were identified in the overall incident AF cohort. Rates of all-cause inpatient hospital stays, all-cause emergency room visits, and all-cause outpatient visits in the overall incident cohort were 46.8, 114.7, and 2,752.7 events per 100 patient-years (PY), respectively. Rates of cardiovascular-related inpatient stays for the overall population were 11.3 events per 100 PY. During follow-up, 50.4% of the overall cohort filled prescriptions for direct-acting oral anticoagulants and 5.0% had catheter ablation.

CONCLUSIONS

Advances in anticoagulation and ablation have been realized since previously published HCRU analyses of patients with atrial fibrillation. This update suggests that HCRU among patients with incident AF in the US remains high with some subgroups of patients receiving more specialized care.

Efficacy and safety of dronedarone by atrial fibrillation history duration: Insights from the ATHENA study

BACKGROUND

Atrial fibrillation/atrial flutter (AF/AFL) burden increases with increasing duration of AF/AFL history.

HYPOTHESIS

Outcomes with dronedarone may also be impacted by duration of AF/AFL history.

METHODS

In this post hoc analysis of ATHENA, efficacy and safety of dronedarone vs placebo were assessed in groups categorized by time from first known AF/AFL episode to randomization (ie, duration of AF/AFL history): <3 months (short), 3 to <24 months (intermediate), and ≥ 24 months (long).

RESULTS

Of 2859 patients with data on duration of AF/AFL history, 45.3%, 29.6%, and 25.1% had short, intermediate, and long histories, respectively. Patients in the long history group had the highest prevalence of structural heart disease and were more likely to be in AF/AFL at baseline. Placebo-treated patients in the long history group also had the highest incidence of AF/AFL recurrence and cardiovascular (CV) hospitalization during the study. The risk of first CV hospitalization/death from any cause was lower with dronedarone vs placebo in patients with short (hazard ratio, 0.79 [95% confidence interval: 0.65-0.96]) and intermediate (0.72 [0.56-0.92]) histories; a trend favoring dronedarone was also observed in patients with long history (0.84 [0.66-1.07]). A similar pattern was observed for first AF/AFL recurrence. No new drug-related safety issues were identified.

CONCLUSIONS

Patients with long AF/AFL history had the highest burden of AF/AFL at baseline and during the study. Dronedarone significantly improved efficacy vs placebo in patients with short and intermediate AF/AFL histories. While exploratory, these results support the potential value in initiating rhythm control treatment early in patients with AF/AFL.