The cost-utility of catheter ablation of atrial fibrillation: a systematic review and critical appraisal of economic evaluations

Cost Effectiveness of Strategies to Manage Atrial Fibrillation in Middle- and High-Income Countries: A Systematic Review

BACKGROUND

Atrial fibrillation (AF) remains the most common form of cardiac arrhythmia. Management of AF aims to reduce the risk of stroke, heart failure and premature mortality via rate or rhythm control. This study aimed to review the literature on the cost effectiveness of treatment strategies to manage AF among adults living in low-, middle- and high-income countries.

METHODS

We searched MEDLINE (OvidSp), Embase, Web of Science, Cochrane Library, EconLit and Google Scholar for relevant studies between September 2022 and November 2022. The search strategy involved medical subject headings or related text words. Data management and selection was performed using EndNote library. The titles and abstracts were screened followed by eligibility assessment of full texts. Selection, assessment of the risk of bias within the studies, and data extraction were conducted by two independent reviewers. The cost-effectiveness results were synthesised narratively. The analysis was performed using Microsoft Excel 365. The incremental cost effectiveness ratio for each study was adjusted to 2021 USD values.

RESULTS

Fifty studies were included in the analysis after selection and risk of bias assessment. In high-income countries, apixaban was predominantly cost effective for stroke prevention in patients at low and moderate risk of stroke, while left atrial appendage closure (LAAC) was cost effective in patients at high risk of stroke. Propranolol was the cost-effective choice for rate control, while catheter ablation and the convergent procedure were cost-effective strategies in patients with paroxysmal and persistent AF, respectively. Among the anti-arrhythmic drugs, sotalol was the cost-effective strategy for rhythm control. In middle-income countries, apixaban was the cost-effective choice for stroke prevention in patients at low and moderate risk of stroke while high-dose edoxaban was cost effective in patients at high risk of stroke. Radiofrequency catheter ablation was the cost-effective option in rhythm control. No data were available for low-income countries.

CONCLUSION

This systematic review has shown that there are several cost-effective strategies to manage AF in different resource settings. However, the decision to use any strategy should be guided by objective clinical and economic evidence supported by sound clinical judgement.

REGISTRATION

CRD42022360590.

Lower number of modifiable risk factors was associated with reduced atrial fibrillation incidence in an 18-year prospective cohort study

Prevention strategies for atrial fibrillation (AF) are lacking. This study aimed to identify modifiable risk factors (MRFs) and estimate their impact on AF in the midlife general population. We assessed 9049 participants who were free of prevalent AF at baseline from the Korean Genome and Epidemiology Study. Cox models with time-varying assessment of risk factors were used to identify significant MRFs for incident AF. The MRF burden was defined as the proportion of visits with MRFs during follow-up. Over a median follow-up of 13.1 years, 182 (2.01%) participants developed AF. Three MRFs, including systolic blood pressure (SBP) ≥ 140 mmHg, obesity with central obesity, and an inactive lifestyle were significantly associated with incident AF. Among participants with 3, 2, 1, and 0 MRFs at baseline, 16 (3.9%), 51 (2.5%), 90 (1.8%) and 25 (1.5%) had incident AF, respectively. Compared to participants with three MRFs, those with one or no MRFs had a decreased risk of AF (hazard ratio [95% CI] for one MRF, 0.483 [0.256-0.914]; and for no MRF, 0.291 [0.145-0.583]). A decreasing MRF burden was associated with reduced AF risk (hazard ratio [95% CI] per 10% decrease in burden for SBP ≥ 140 mmHg, 0.937 [0.880-0.997]; for obesity with central obesity, 0.942 [0.907-0.978]; for inactivity, 0.926 [0.882-0.973]). Maintaining or achieving MRF ≤ 1 was associated with decreased AF risk, suggesting that minimizing the burden of MRF might help prevent AF.

Comparative Clinical Effectiveness of Population-Based Atrial Fibrillation Screening Using Contemporary Modalities: A Decision-Analytic Model

Background Atrial fibrillation (AF) screening is endorsed by certain guidelines for individuals aged ≥65 years. Yet many AF screening strategies exist, including the use of wrist-worn wearable devices, and their comparative effectiveness is not well-understood. Methods and Results We developed a decision-analytic model simulating 50 million individuals with an age, sex, and comorbidity profile matching the United States population aged ≥65 years (ie, with a guideline-based AF screening indication). We modeled no screening, in addition to 45 distinct AF screening strategies (comprising different modalities and screening intervals), each initiated at a clinical encounter. The primary effectiveness measure was quality-adjusted life-years, with incident stroke and major bleeding as secondary measures. We defined continuous or nearly continuous modalities as those capable of monitoring beyond a single time-point (eg, patch monitor), and discrete modalities as those capable of only instantaneous AF detection (eg, 12-lead ECG). In total, 10 AF screening strategies were effective compared with no screening (300-1500 quality-adjusted life-years gained/100 000 individuals screened). Nine (90%) effective strategies involved use of a continuous or nearly continuous modality such as patch monitor or wrist-worn wearable device, whereas 1 (10%) relied on discrete modalities alone. Effective strategies reduced stroke incidence (number needed to screen to prevent a stroke: 3087-4445) but increased major bleeding (number needed to screen to cause a major bleed: 1815-4049) and intracranial hemorrhage (number needed to screen to cause intracranial hemorrhage: 7693-16 950). The test specificity was a highly influential model parameter on screening effectiveness. Conclusions When modeled from a clinician-directed perspective, the comparative effectiveness of population-based AF screening varies substantially upon the specific strategy used. Future screening interventions and guidelines should consider the relative effectiveness of specific AF screening strategies.

Ablation for paroxysmal atrial fibrillation-real-life results from a middle-volume electrophysiology laboratory

Introduction

A significant improvement in safety and efficacy of ablation for paroxysmal atrial fibrillation (PAF) has been reported by experienced centers over recent years; however, data from real-life surveys and smaller electrophysiology (EP) laboratories have been less optimistic.

Aim

To asses efficacy of ablation for PAF in a middle-volume EP center over last years.

Methods

Retrospective analysis of 1 year efficacy and safety of ablation for PAF in three cohorts of patients treated between 2011 and 2014 (period I), 2015–2017 (period II), and 2018–2019 (period III).

Results

Of 234 patients (mean age 57 ± 9 years, 165 males), 81 (35%) were treated in period I, 84 (36%) in period II, and 69 (29%) in period III. The overall efficacy of ablation during all analyzed periods was 67%. The overall efficacy of ablation increased over time—from 56% in period I to 68% in period II and 81% in period III. Significant improvement was achieved using radiofrequency ablation (RF) (53% in period I vs 82% in period III, and 55% in period II vs 82% in period III, p = 0.003 and 0.0012, respectively) whereas positive trend in the improvement of cryoballoon efficacy was NS. The rate of peri-procedural complications was 9% and it did not change significantly over time.

Conclusions

This real-life observational study from a medium volume EP center shows that progress in PAF ablation, especially RF, reported by highly-skilled centers, can be reproduced in real life by less experienced operators.

Cost-effectiveness of combined catheter ablation and left atrial appendage closure for symptomatic atrial fibrillation in patients with high stroke and bleeding risk

BACKGROUND

Combined catheter ablation (CA) and left atrial appendage closure (LAAC) have been proposed for management of symptomatic atrial fibrillation (AF) in patients with high stroke and bleeding risk. We assessed the cost-effectiveness of combined CA and LAAC compared with CA and standard oral anticoagulation (OAC) in symptomatic AF.

METHODS

A Markov model was developed to assess total costs, quality-adjusted life-years (QALYs), and the incremental cost-effectiveness ratio among 2 post-CA strategies: (1) standard OAC and (2) LAAC (combined CA and LAAC procedure). The base-case used a 10-year time horizon and consisted of a hypothetical cohort of patients aged 65 years with symptomatic AF, with high thrombotic (CHA₂DS₂-VASc = 3) and bleeding risk (HAS-BLED = 3), and planned for AF ablation. Values for transition probabilities, utilities, and costs were derived from the literature. Costs were converted to 2020 US dollars. Half-cycle correction was applied, and costs and QALYs were discounted at 3% annually. Sensitivity analyses were performed for significant variables and scenario analyses for higher embolic risk.

RESULTS

In the base-case cohort of 10,000 patients followed for 10 years, total costs for the LAAC strategy were $29,027 and for OAC strategy were $27,896. The LAAC strategy was associated with 122 fewer disabling strokes and 203 fewer intracranial hemorrhages per 10,000 patients compared with the OAC strategy. The LAAC strategy had an incremental cost-effectiveness ratio of $11,072/QALY. In sensitivity analyses, although cost-effectiveness was highly dependent on the risk of intracranial hemorrhage in the LAAC strategy and the cost of the combined procedure, LAAC was superior to OAC under the most circumstances. Scenario analyses demonstrated that the combined procedure was more cost-effective in patients with higher stroke risk.

CONCLUSIONS

In symptomatic AF patients with high stroke and bleeding risk who are planned for CA, the combined CA and LAAC procedure may be a cost-effective therapeutic option and be more beneficial to patients with CHA₂DS₂-VASc risk score ≥3.

Economic Evaluation of Catheter Ablation of Atrial Fibrillation in Patients with Heart Failure With Reduced Ejection Fraction

BACKGROUND

Randomized clinical trials have demonstrated that catheter ablation for atrial fibrillation in patients with heart failure with reduced ejection fraction may improve survival and other cardiovascular outcomes.

METHODS

We constructed a decision-analytic Markov model to estimate the costs and benefits of catheter ablation and medical management in patients with symptomatic heart failure with reduced ejection fraction (left ventricular ejection fraction ≤35%) and atrial fibrillation over a lifetime horizon. Evidence from the published literature informed the model inputs, including clinical effectiveness data from meta-analyses. Probabilistic and deterministic sensitivity analyses were performed. A 3% discount rate was applied to both future costs and benefits. The primary outcome was the incremental cost-effectiveness ratio assessed from the US health care sector perspective.

RESULTS

Catheter ablation was associated with 6.47 (95% CI, 5.89-6.93) quality-adjusted life years (QALYs) and a total cost of $105 657 (95% CI, $55 311-$191 934; 2018 US dollars), compared with 5.30 (95% CI, 5.20-5.39) QALYs and $63 040 (95% CI, $37 624-$102 260) for medical management. The incremental cost-effectiveness ratio for catheter ablation compared with medical management was $38 496 (95% CI, $5583-$117 510) per QALY gained. Model inputs with the greatest variation on incremental cost-effectiveness ratio estimates were the cost of ablation and the effect of catheter ablation on mortality reduction. When assuming a more conservative estimate of the treatment effect of catheter ablation on mortality (hazard ratio of 0.86), the estimated incremental cost-effectiveness ratio was $74 403 per QALY gained. At a willingness-to-pay threshold of $100 000 per QALY gained, atrial fibrillation ablation was found to be economically favorable compared with medical management in 95% of simulations.

CONCLUSIONS

Catheter ablation in patients with heart failure with reduced ejection fraction patients and atrial fibrillation may be considered economically attractive at current benchmarks for societal willingness-to-pay in the United States.

Gaps in patient-reported outcome measures in randomized clinical trials of cardiac catheter ablation: a systematic review

The aim of this systematic review was to evaluate randomized clinical trials (RCTs) of cardiac catheter ablation (CCA) and to assess the prevalence, characteristics and reporting standards of clinically relevant patient-reported outcome measures (PROMs). Electronic database searches of Medline, Embase, CENTRAL, and the WHO Trial Registry were conducted in March 2019. The study protocol was registered on PROSPERO (CRD42019133086). Of 7125 records identified, 237 RCTs were included for analysis, representing 35 427 patients with a mean age of 59 years. Only 43 RCTs (18%) reported PROMs of which 27 included a generic PROM that measured health-related quality of life (HRQL) necessary to conduct comparative effectiveness research. There was notable under-representation of certain patient groups—only 31% were women and only 8% were of non-Caucasian ethnicity, in trials which reported such data. The reporting standard of PROMs was highly variable with 8–62% adherence against CONSORT PRO-specific items. In summary, PROMs play a crucial role in determining the clinical and cost-effectiveness of treatments which primarily offer symptomatic improvement, such as CCA. Their underuse significantly limits evaluation of the comparative effectiveness of treatments. Using CCA as an exemplar, there are additional issues of infrequent assessment, poor reporting and under-representation of many population groups. Greater use of PROMs, and specifically validated HRQL questionnaires, is paramount in giving patients a voice in studies, generating more meaningful comparisons between treatments and driving better patient-centred clinical and policy-level decision-making.

Impact of catheter ablation therapy for atrial fibrillation on healthcare expenditures in a middle European cohort

Aims

Atrial fibrillation (AF) is the most prevalent arrhythmia in western countries. It is associated with increased mortality and morbidity and responsible for hospitalization rates of 10–40% per patient per year. Studies from the UK and the USA have shown that AF is responsible for ∼1% of the total healthcare expenditures in these countries. The only potentially curative treatment is pulmonary vein isolation (PVI). Published health economic data on the impact of PVI mainly consist of simulations of expenditures with assumed efficacy taken from ablation studies. Real expenditure data are missing as well as pre-ablation period data and long-term data.

Methods and results

We analyse true healthcare expenditures based on inpatient and outpatient data from the Upper Austrian Health Insurance Fund social security system of patients undergoing PVI during 2005 to 2015. We identified 1135 patients undergoing PVI with 268 having multiple procedures. Days of hospitalization and days of sick leave started to rise in the year before ablation. PVI was able to lower both parameters to the level of 1 year before ablation. Comparing four quarters before and after a single-index ablation, a highly significant reduction in inpatient healthcare expenditures was documented. There was a significant, but numerically small increase in outpatient expenditures, resulting in a significant reduction in overall healthcare expenditures.

Conclusion

Analysing a cohort of the Upper Austrian Health Insurance Fund undergoing PVI, we found significant cost-saving effects on post-interventional healthcare expenditures and a reduction in days of sick leave.

A Long-Term Cost-Effectiveness Analysis Comparing Radiofrequency Catheter Ablation with Antiarrhythmic Drugs in Treatment of Chinese Patients with Atrial Fibrillation

INTRODUCTION

Radiofrequency catheter ablation (RFCA) is widely used to treat atrial fibrillation (AF) in China.

OBJECTIVE

We aimed to determine the long-term cost effectiveness of RFCA versus antiarrhythmic drugs (AADs) in treating AF from the perspective of third-party payers.

METHODS

The model was structured as a 12-month decision tree leading to a Markov model that simulated the follow-up treatment outcomes and costs with time horizons of 8, 15, and 20 years. Comparators were standard-of-care AADs. Clinical parameters captured normal sinus rhythm, AF, stroke, post-stroke, intracranial hemorrhage (ICH), gastrointestinal bleeding, post-ICH, and death. The risk of operative death, procedural complications, and adverse drug toxicity were also considered. The model output was quality-adjusted life-years (QALYs) and incremental cost per QALY gained.

RESULTS

RFCA incurred more costs than the AADs but resulted in more QALYs gained than did AADs. The incremental cost per QALY gained with RFCA versus AADs was ¥66,764, ¥36,280, and ¥29,359 at 8, 15, and 20 years, respectively. The sensitivity analyses showed that the results were most sensitive to the changes in RFCA cost and CHADS₂ score (clinical prediction rule for assessing the risk of stroke in patients with non-rheumatic AF).

CONCLUSION

Compared with AADs, RFCA significantly improves clinical outcomes and QALYs among patients with paroxysmal or persistent AF. From the Chinese payer's perspective, RFCA is a cost-effective therapy over long-term horizons.

Amaze: a double-blind, multicentre randomised controlled trial to investigate the clinical effectiveness and cost-effectiveness of adding an ablation device-based maze procedure as an adjunct to routine cardiac surgery for patients with pre-existing atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) can be treated using a maze procedure during planned cardiac surgery, but the effect on clinical patient outcomes, and the cost-effectiveness compared with surgery alone, are uncertain.

OBJECTIVES

To determine whether or not the maze procedure is safe, improves clinical and patient outcomes and is cost-effective for the NHS in patients with AF.

DESIGN

Multicentre, Phase III, pragmatic, double-blind, parallel-arm randomised controlled trial. Patients were randomised on a 1 : 1 basis using random permuted blocks, stratified for surgeon and planned procedure.

SETTING

Eleven acute NHS specialist cardiac surgical centres.

PARTICIPANTS

Patients aged ≥ 18 years, scheduled for elective or in-house urgent cardiac surgery, with a documented history (> 3 months) of AF.

INTERVENTIONS

Routine cardiac surgery with or without an adjunct maze procedure administered by an AF ablation device.

MAIN OUTCOME MEASURES

The primary outcomes were return to sinus rhythm (SR) at 12 months and quality-adjusted life-years (QALYs) over 2 years after randomisation. Secondary outcomes included return to SR at 2 years, overall and stroke-free survival, drug use, quality of life (QoL), cost-effectiveness and safety.

RESULTS

Between 25 February 2009 and 6 March 2014, 352 patients were randomised to the control (n = 176) or experimental (n = 176) arms. The odds ratio (OR) for return to SR at 12 months was 2.06 [95% confidence interval (CI) 1.20 to 3.54; p = 0.0091]. The mean difference (95% CI) in QALYs at 2 years between the two trial arms (maze/control) was -0.025 (95% CI 0.129 to 0.078; p = 0.6319). The OR for SR at 2 years was 3.24 (95% CI 1.76 to 5.96). The number of patients requiring anticoagulant drug use was significantly lower in the maze arm from 6 months after the procedure. There were no significant differences between the two arms in operative or overall survival, stroke-free survival, need for cardioversion or permanent pacemaker implants, New York Heart Association Functional Classification (for heart failure), EuroQol-5 Dimensions, three-level version score and Short Form questionnaire-36 items score at any time point. Sixty per cent of patients in each trial arm had a serious adverse event (p = 1.000); most events were mild, but 71 patients (42.5%) in the maze arm and 84 patients (45.5%) in the control arm had moderately severe events; 31 patients (18.6%) in the maze arm and 38 patients (20.5%) in the control arm had severe events. The mean additional cost of the maze procedure was £3533 (95% CI £1321 to £5746); the mean difference in QALYs was -0.022 (95% CI -0.1231 to 0.0791). The maze procedure was not cost-effective at £30,000 per QALY over 2 years in any analysis. In a small substudy, the active left atrial ejection fraction was smaller than that of the control patients (mean difference of -8.03, 95% CI -12.43 to -3.62), but within the predefined clinically equivalent range.

LIMITATIONS

Low recruitment, early release of trial summaries and intermittent resource-use collection may have introduced bias and imprecise estimates.

CONCLUSIONS

Ablation can be practised safely in routine NHS cardiac surgical settings and increases return to SR rates, but not survival or QoL up to 2 years after surgery. Lower anticoagulant drug use and recovery of left atrial function support anticoagulant drug withdrawal provided that good atrial function is confirmed.

FURTHER WORK

Continued follow-up and long-term clinical effectiveness and cost-effectiveness analysis. Comparison of ablation methods.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN82731440.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 19. See the NIHR Journals Library website for further project information.

Individual and combined impact of lifestyle factors on atrial fibrillation in apparently healthy men and women: The EPIC-Norfolk prospective population study

Background

Lifestyle factors are important targets for prevention. The cumulative impact of healthy lifestyle on atrial fibrillation in the population has not been quantified.

Design

Prospective population-based cohort study.

Methods

Four lifestyle factors (normal weight, currently not smoking, no or moderate alcohol intake, and physically not inactive) were assessed in apparently healthy 21,499 men and women aged 39–79 years participating in the EPIC study in Norfolk, UK. The age and sex-adjusted hazard (95% confidence interval) of hospital admission with a diagnosis of atrial fibrillation during an average follow-up of 17.1 years was examined for each factor separately and for a health score comprising factors with significant impact.

Results

Normal weight, currently not smoking and low alcohol intake were associated with a significantly lower risk of atrial fibrillation, whereas not being physically inactive showed no significant association. We used a score of one point each for not smoking, low alcohol intake and body mass index 25 to 27.5 kg/m2, and two points for body mass index < 25 kg/m2. Compared with men and women with four health points, hazard ratios of atrial fibrillation were 1.25 (1.11–1.41), 1.56 (1.39–1.75), 1.83 (1.56–2.16) and 2.82 (1.85–4.29) for participants with three, two, one and no health points, respectively ( p < 0.0001 for trend). Results were consistent by sex, age, education level, social class and after excluding participants with hypertension and diabetes.

Conclusion

Three lifestyle factors combined predict an almost 2.8-fold difference in the risk of atrial fibrillation in men and women.

A meta-analysis on Omega-3 supplements in preventing recurrence of atrial fibrillation

Previous studies had suggested that Omega-3 fatty acids have pleiotropic effects and favourable safety profile, which may potentially increase the efficacy of antiarrhythmic drugs in suppressing atrial arrhythmias through combination therapy. This meta-analysis aimed to determine the effectiveness of using Omega-3 polyunsaturated fatty acids as a sole anti-arrhythmic agent or as an adjunct to existing pharmacological therapies in preventing atrial fibrillation recurrence. Randomized controlled trials published in English, from inception to December 2016, were considered. We searched for published studies in the following electronic databases: Cochrane Central Register of Controlled Trials, PubMed, EMBASE, Medline, Scopus, and Cumulative Index to Nursing and Allied Health Literature. Pooled hazard ratio (HR) and corresponding 95% confidence intervals (CI) for time to first atrial fibrillation recurrence was analysed using a fixed effects model. Four RCTs with 1,268 participants were included in the review. Our results showed that Omega-3 polyunsaturated fatty acid therapy had no effect on preventing atrial fibrillation recurrence compared to control/placebo group (HR: 1.13, 95% CI: 0.96 to 1.33, p = 0.14), with no significant heterogeneity found among those studies (Q value = 0.15, 9 = 0.99, I² = 0%). Therefore, current evidence does not support treatment benefit of Omega-3 fatty acids in preventing atrial fibrillation recurrence among patients who have not been treated by any conventional reversion treatment, or who have only been treated with pharmacological therapy.

Cost-effectiveness of Catheter Ablation Versus Antiarrhythmic Drug Therapy for the Treatment of Atrial Fibrillation: A Canadian Perspective

Background: Atrial fibrillation (AF) affects approximately 350,000 Canadians and has an estimated annual economic burden exceeding $800 million dollars. Anti-arrhythmic drug (AAD) therapy and catheter ablation (CA) are the two common treatments for paroxysmal AF. However, the upfront costs of CA are quite substantial. Objective: The objective of this study was to assess the cost-effectiveness of CA compared to AAD for AF based on community practice. Methods: A Markov simulation model was developed for a hypothetical cohort of 55-year-old patients with paroxysmal AF and a low stroke risk. Patients received either CA or AAD. Costs and quality-adjusted life years (QALYs) were computed over lifetime, 10-year, and 5-year time horizons. Model inputs were obtained from a large, prospectively collected, single-center Canadian registry and augmented with the published literature, using Canadian cost estimates for disease states. Threshold values of $25,000, $50,000, and $100,000 per QALY, respectively, were used to determine cost-effectiveness. All costs were expressed in 2012 Canadian dollars. Results: The incremental cost-effectiveness ratio for CA versus AAD therapy was $1,228, $22,879, and $63,647 for the lifetime, 10-year, and 5-year time horizons, respectively. Over a lifetime horizon, the probability of achieving cost-effectiveness was 100% for all 3 cost per QALY thresholds. The 10-year probability of achieving cost-effectiveness was 74%, 100%, and 100% at the $25,000, $50,000, and $100,000 thresholds, respectively. The 5-year probability of achieving cost-effectiveness was 0%, 0.9%, and 100% at the 3 cost per QALY thresholds. Results were most sensitive to time horizon, probability of repeat AF ablation, and stroke rate. Conclusions: From the perspective of the Canadian Healthcare system, CA is a potentially cost-effective treatment compared to AAD therapy in a low stroke risk population using real-world data when examining a time horizon of greater than 5 years.

Cryoballoon or radiofrequency ablation for symptomatic paroxysmal atrial fibrillation: reintervention, rehospitalization, and quality-of-life outcomes in the FIRE AND ICE trial

AIMS

The primary safety and efficacy endpoints of the randomized FIRE AND ICE trial have recently demonstrated non-inferiority of cryoballoon vs. radiofrequency current (RFC) catheter ablation in patients with drug-refractory symptomatic paroxysmal atrial fibrillation (AF). The aim of the current study was to assess outcome parameters that are important for the daily clinical management of patients using key secondary analyses. Specifically, reinterventions, rehospitalizations, and quality-of-life were examined in this randomized trial of cryoballoon vs. RFC catheter ablation.

METHODS AND RESULTS

Patients (374 subjects in the cryoballoon group and 376 subjects in the RFC group) were evaluated in the modified intention-to-treat cohort. After the index ablation, log-rank testing over 1000 days of follow-up demonstrated that there were statistically significant differences in favour of cryoballoon ablation with respect to repeat ablations (11.8% cryoballoon vs. 17.6% RFC; P = 0.03), direct-current cardioversions (3.2% cryoballoon vs. 6.4% RFC; P = 0.04), all-cause rehospitalizations (32.6% cryoballoon vs. 41.5% RFC; P = 0.01), and cardiovascular rehospitalizations (23.8% cryoballoon vs. 35.9% RFC; P < 0.01). There were no statistical differences between groups in the quality-of-life surveys (both mental and physical) as measured by the Short Form-12 health survey and the EuroQol five-dimension questionnaire. There was an improvement in both mental and physical quality-of-life in all patients that began at 6 months after the index ablation and was maintained throughout the 30 months of follow-up.

CONCLUSION

Patients treated with cryoballoon as opposed to RFC ablation had significantly fewer repeat ablations, direct-current cardioversions, all-cause rehospitalizations, and cardiovascular rehospitalizations during follow-up. Both patient groups improved in quality-of-life scores after AF ablation.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01490814.

Electrophysiological Perspectives on Hybrid Ablation of Atrial Fibrillation

To overcome limitations of minimally invasive surgical ablation as a standalone procedure in eliminating atrial fibrillation (AF), hybrid approaches incorporating adjunctive endovascular catheter ablation have been proposed in recent years. The endovascular component targets residual conduction gaps and identifies additional electrophysiological targets with the goal of minimizing recurrent atrial arrhythmia. We performed a systematic review of published studies of hybrid AF ablation, analyzing 432 pooled patients (19% paroxysmal, 29% persistent, 52% long-standing persistent) treated using three different approaches: A. bilateral thoracoscopy with bipolar radiofrequency (RF) clamp-based approach; B. right thoracoscopic suction monopolar RF catheter-based approach; and C. subxiphoid posterior pericardioscopic ("convergent") approach. Freedom from recurrence off antiarrhythmic medications at 12 months was seen in 88.1% [133/151] for A, 73.4% [47/64] for B, and 59.3% [80/135] for C, with no significant difference between paroxysmal (76.9%) and persistent/long-standing persistent AF (73.4%). Death and major surgical complications were reported in 8.5% with A, 0% with B and 8.6% with C. A critical appraisal of hybrid ablation is presented, drawing from experiences and insights published over the years on catheter ablation of AF, with a discussion of the rationale underlying hybrid ablation, its strengths and limitations, where it may have a unique role in clinical management of patients with AF, which questions remain unanswered and areas for further investigation.

Demographic Differences in Catheter Ablation After Hospital Presentation With Symptomatic Atrial Fibrillation

BACKGROUND

Catheter ablation is increasingly used for rhythm control in symptomatic atrial fibrillation (AF), but the demographic characteristics of patients undergoing this procedure are unclear.

METHODS AND RESULTS

We used data on all admissions at nonfederal acute care hospitals in California, Florida, and New York to identify patients discharged with a primary diagnosis of AF between 2006 and 2011. Our primary outcome was readmission for catheter ablation of AF, identified using validated International Classification of Diseases, Ninth Revision, Clinical Modification procedure codes. Cox regression models were used to assess relationships between demographic characteristics and catheter ablation, adjusting for Elixhauser comorbidities. We identified 397 612 eligible patients. Of these, 16 717 (4.20%, 95% CI 0.41 to 0.43) underwent ablation. These patients were significantly younger, more often male, more often white, and more often privately insured, with higher household incomes and lower rates of medical comorbidity. In Cox regression models, the likelihood of ablation was lower in women than men (hazard ratio [HR] 0.83; 95% CI 0.80 to 0.86) despite higher rates of AF-related rehospitalization (HR 1.23; 95% CI 1.21 to 1.24). Compared to whites, the likelihood of ablation was lower in Hispanics (HR 0.60; 95% CI 0.56 to 0.64) and blacks (HR 0.68; 95% CI 0.64 to 0.73), even though blacks had only a slightly lower likelihood of AF-related rehospitalization (HR 0.97; 95% CI 0.94 to 0.99) and a higher likelihood of all-cause hospitalization (HR 1.38; 95% CI 1.37 to 1.39). Essentially the same pattern existed in Hispanics.

CONCLUSIONS

We found differences in use of catheter ablation for symptomatic AF according to sex and race despite adjustment for available data on demographic characteristics and medical comorbidities.

Attitudes toward Catheter Ablation for Atrial Fibrillation: A Nationwide Survey among Danish Cardiologists

BACKGROUND

Catheter ablation for atrial fibrillation (AF) is an important but expensive procedure that is the subject of some debate. Physicians' attitudes toward catheter ablation may influence promotion and patient acceptance. This is the first study to examine the attitudes of Danish cardiologists toward catheter ablation for AF, using a nationwide survey.

METHODS AND RESULTS

We developed a purpose-designed questionnaire to evaluate attitudes toward catheter ablation for AF that was sent to all Danish cardiologists (n = 401; response n = 272 (67.8%)). There was no association between attitudes toward ablation and the experience or age of the cardiologist with respect to patients with recurrent AF episodes with a duration of <48 hours or >7 days and/or need for cardioversion. The majority (69%) expected a recurrence of AF after catheter ablation in more than 30% of the cases. For patients with persistent longstanding AF with a duration of >1 year, the attitude toward ablation for longstanding AF was more likely to be positive with increasing age (P < 0.01) and years of experience of the cardiologist (P = 0.002).

CONCLUSIONS

Danish cardiologists generally have a positive attitude toward catheter ablation for AF, maintain up-to-date knowledge of the procedure, and are aware what information on ablation treatment should be given to patients with AF. The cardiologists had a positive attitude toward ablation for AF in patients with AF episodes <48 hours and patients with episodes >7 days, or those who needed medical/electrical conversion, but a more negative attitude toward treating longstanding AF patients.

Fish oil for the reduction of atrial fibrillation recurrence, inflammation, and oxidative stress

BACKGROUND

Recent trials of fish oil for the prevention of atrial fibrillation (AF) recurrence have provided mixed results. Notable uncertainties in the existing evidence base include the roles of high-dose fish oil, inflammation, and oxidative stress in patients with paroxysmal or persistent AF not receiving conventional antiarrhythmic (AA) therapy.

OBJECTIVES

The aim of this study was to evaluate the influence of high-dose fish oil on AF recurrence, inflammation, and oxidative stress parameters.

METHODS

We performed a double-blind, randomized, placebo-controlled, parallel-arm study in 337 patients with symptomatic paroxysmal or persistent AF within 6 months of enrollment. Patients were randomized to fish oil (4 g/day) or placebo and followed, on average, for 271 ± 129 days.

RESULTS

The primary endpoint was time to first symptomatic or asymptomatic AF recurrence lasting >30 s. Secondary endpoints were high-sensitivity C-reactive protein (hs-CRP) and myeloperoxidase (MPO). The primary endpoint occurred in 64.1% of patients in the fish oil arm and 63.2% of patients in the placebo arm (hazard ratio: 1.10; 95% confidence interval: 0.84 to 1.45; p = 0.48). hs-CRP and MPO were within normal limits at baseline and decreased to a similar degree at 6 months (Δhs-CRP, 11% vs. -11%; ΔMPO, -5% vs. -9% for fish oil vs. placebo, respectively; p value for interaction = NS).

CONCLUSIONS

High-dose fish oil does not reduce AF recurrence in patients with a history of AF not receiving conventional AA therapy. Furthermore, fish oil does not reduce inflammation or oxidative stress markers in this population, which may explain its lack of efficacy. (Multi-center Study to Evaluate the Effect of N-3 Fatty Acids [OMEGA-3] on Arrhythmia Recurrence in Atrial Fibrillation [AFFORD]; NCT01235130).