Background Women with atrial fibrillation (AF) demonstrate more AF‐related symptoms and worse quality of life (QOL). Whether increased use of ablation in women reduces sex‐related QOL differences is unknown. Sex‐related outcomes for ablation versus drug therapy was a prespecified analysis in the CABANA (Catheter Ablation Versus Antiarrhythmic Drug Therapy for Atrial Fibrillation) trial. Methods and Results Symptoms were assessed periodically over 60 months with the Mayo AF‐Specific Symptom Inventory (MAFSI) frequency score, and QOL was assessed with the Atrial Fibrillation Effect on Quality of Life (AFEQT) summary and component scores. Women had lower baseline QOL scores than men (mean AFEQT scores 55.9 and 65.6, respectively). Ablation patients improved more than drug therapy patients with similar treatment effect by sex: AFEQT 12‐month mean adjusted treatment difference in women 6.1 points (95% CI, 3.5–8.6) and men 4.9 points (95% CI, 3.0–6.9). Participants with baseline AFEQT summary scores <70 had greater QOL improvement, with a mean treatment difference at 12 months of 7.6 points for women (95% CI, 4.3–10.9) and 6.4 points for men (95% CI, 3.3–9.4). The mean adjusted difference in MAFSI frequency score between women randomized to ablation versus drug therapy at 12 months was −2.5 (95% CI, −3.4 to −1.6); for men, the difference was −1.3 (95% CI, −2.0 to −0.6). Conclusions Compared with drug therapy for AF, ablation resulted in more QOL improvement in both sexes, primarily driven by improvements in those with lower baseline QOL. Ablation did not eliminate the AF‐related QOL gap between women and men. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00911508.
Pulmonary vein stenosis – ballooning vs. stenting: a systematic review and meta-analysis
Abstract Background Pulmonary vein stenosis (PVS), which is often unrecognized, may arise from a variety of conditions resulting in major morbidity and mortality. In some patients, pharmacological therapy may help but more often in advance stages, mechanical treatment must be considered. Transcatheter approaches, both balloon angioplasty (BA) and stent implantation have been applied. While both may be effective, they continue to be limited by restenosis. Herein, we compare the outcomes following BA and stenting for PVS. Purpose PVS presents a challenge for both diagnosis and therapy, with BA and stenting being primarily limited by restenosis. Stenting is performed in most cases and is associated with improved patency rates. Historical comparisons of BA and stenting for PVS have yielded similar results. Our analysis incorporates more conventional studies (2010–2021) and provides a larger stent (N=361) versus BA (N=229) contemporary analysis of the current state of PV intervention practice. Methods From January 1, 2010 to August 2, 2021, studies, limited to English language and humans, were assessed in Ovid MEDLINE®, Ovid Embase, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus. Two independent reviewers screened articles including those in which balloon angioplasty or stenting was performed for pulmonary vein stenosis with reporting of restenosis outcomes and data was independently extracted. Systematic review was performed, and overall restenosis rates were reported across all included studies. Meta-analysis was then performed using RevMan 5.4 assessing rates of restenosis and restenosis requiring repeat intervention. Results Our systematic review yielded 34 studies reporting on BA and/or stenting for PVS. Of these, 7 studies (1–7), treating a total of 343 patients with 590 PV interventions (229 BA and 361 Stents) reported restenosis rates with mean follow-up ranging from 10 to 60 months. Stenting was associated with a lower risk of restenosis compared to balloon angioplasty [risk ratio 0.35, 95% CI (0.18, 0.64), p=0.0008] (Figure 1). Restenosis requiring repeat intervention was reported in 5 studies, including 303 patients with 502 PV interventions (160 BA and 342 Stents) with stenting similarly associated with a lower risk of restenosis requiring re-intervention [risk ratio 0.34, 95% CI (0.16, 0.72), p=0.005]. Conclusion Stenting for pulmonary vein stenosis is associated with reduced risk of restenosis and re-intervention as compared to balloon angioplasty. Funding Acknowledgement Type of funding sources: None.
Cost-Effectiveness of Catheter Ablation Versus Antiarrhythmic Drug Therapy in Atrial Fibrillation: The CABANA Randomized Clinical Trial
Background: In the CABANA trial (Catheter Ablation vs Antiarrhythmic Drug Therapy for Atrial Fibrillation), catheter ablation did not significantly reduce the primary end point of death, disabling stroke, serious bleeding, or cardiac arrest compared with drug therapy by intention-to-treat, but did improve the quality of life and freedom from atrial fibrillation recurrence. In the heart failure subgroup, ablation improved both survival and quality of life. Cost-effectiveness was a prespecified CABANA secondary end point. Methods: Medical resource use data were collected for all CABANA patients (N=2204). Costs for hospital-based care were assigned using prospectively collected bills from US patients (n=1171); physician and medication costs were assigned using the Medicare Fee Schedule and National Average Drug Acquisition Costs, respectively. Extrapolated life expectancies were estimated using age-based survival models. Quality-of-life adjustments were based on EQ-5D–based utilities measured during the trial. The primary outcome was the incremental cost-effectiveness ratio, comparing ablation with drug therapy on the basis of intention-to-treat, and assessed from the US health care sector perspective. Results: Costs in the first 3 months averaged $20 794±SD 1069 higher with ablation compared with drug therapy. The cumulative within-trial 5-year cost difference was $19 245 (95% CI, $11 360–$27 170) and the lifetime mean cost difference was $15 516 (95% CI, –$2963 to $35,512) higher with ablation than with drug therapy. The drug therapy arm accrued an average of 12.5 life-years (LYs) and 10.7 quality-adjusted life-years (QALYs). For the ablation arm, the corresponding estimates were 12.6 LYs and 11.0 QALYs. The incremental cost-effectiveness ratio was $57 893 per QALY gained, with 75% of bootstrap replications yielding an incremental cost-effectiveness ratio < $100 000 per QALY gained. With no quality-of-life/utility adjustments, the incremental cost-effectiveness ratio was $183 318 per LY gained. Conclusions: Catheter ablation of atrial fibrillation was economically attractive compared with drug therapy in the CABANA Trial overall at present benchmarks for health care value in the United States on the basis of projected incremental QALYs but not LYs alone.
Ablation of Refractory Ventricular Tachycardia Using Intramyocardial Needle Delivered Heated Saline-Enhanced Radiofrequency Energy: A First-in-Man Feasibility Trial
Background: Ablation of ventricular tachycardia (VT) is limited by the inability to create penetrating lesions to reach intramyocardial origins. Intramural needle ablation using in-catheter, heated saline-enhanced radio frequency (SERF) energy uses convective heating to increase heat transfer and produce deeper, controllable lesions at intramural targets. This first-in-human trial was designed to evaluate the safety and efficacy of SERF needle ablation in patients with refractory VT. Methods: Thirty-two subjects from 6 centers underwent needle electrode ablation. Each had recurrent drug-refractory monomorphic VT after implantable cardioverter defibrillator implantation and prior standard ablation. During the SERF study procedure, one or more VTs were induced and mapped. The SERF needle catheter was used to create intramural lesions at targeted VT site(s). Acute procedural success was defined as noninducibility of the clinical VT after the procedure. Patients underwent follow-up at 30 days, and 3 and 6 months, with implantable cardioverter defibrillator interrogation at follow-up to determine VT recurrence. Results: These refractory VT patients (91% male, 66±10 years, ejection fraction 35±11%; 56% ischemic, and 44% nonischemic) had a median of 45 device therapies (shock/antitachycardia pacing) for VT in the 3 to 6 months pre-SERF ablation. The study catheter was used to deliver an average of 10±5 lesions per case, with an average of 430±295 seconds of radiofrequency time, 122±65 minute of catheter use time, and a procedural duration of 4.3±1.3 hours. Acute procedural success was 97% for eliminating the clinical VT. At average follow-up of 5 months (n=32), device therapies were reduced by 89%. Complications included 2 periprocedural deaths: an embolic mesenteric infarct and cardiogenic shock, 2 mild strokes, and a pericardial effusion treated with pericardiocentesis (n=1). Conclusions: Intramural heated saline needle ablation showed complete acute and satisfactory mid-term control of difficult VTs failing 1 to 5 prior ablations and drug therapy. Further study is warranted to define safety and longer-term efficacy. Registration: URL: https://www.clinicaltrials.gov ; Unique Identifier: NCT03628534 and NCT02994446.
Generalizability of the EAST‐AFNET 4 Trial: Assessing Outcomes of Early Rhythm‐Control Therapy in Patients With Atrial Fibrillation
Background EAST‐AFNET 4 (Early Treatment of Atrial Fibrillation for Stroke Prevention Trial) demonstrated clinical benefit of early rhythm‐control therapy (ERC) in patients with new‐onset atrial fibrillation (AF) and concomitant cardiovascular conditions compared with current guideline‐based practice. This study aimed to evaluate the generalizability of EAST‐AFNET 4 in routine practice. Methods and Results Using a US administrative database, we identified 109 739 patients with newly diagnosed AF during the enrollment period of EAST‐AFNET 4. Patients were classified as either receiving ERC, using AF ablation or antiarrhythmic drug therapy, within the first year after AF diagnosis (n=27 106) or not receiving ERC (control group, n=82 633). After propensity score overlap weighting, Cox proportional hazards regression was used to compare groups for the primary composite outcome of all‐cause mortality, stroke, or hospitalization with the diagnoses heart failure or myocardial infarction. Most patients (79 948 of 109 739; 72.9%) met the inclusion criteria for EAST‐AFNET 4. ERC was associated with a reduced risk for the primary composite outcome (hazard ratio [HR], 0.85; 95% CI, 0.75–0.97 [ P =0.02]) with largely consistent results between eligible (HR, 0.89; 95% CI, 0.76–1.04 [ P =0.14]) or ineligible (HR, 0.77; 95% CI, 0.60–0.98 [ P =0.04]) patients for EAST‐AFNET 4 trial inclusion. ERC was associated with lower risk of stroke in the overall cohort and in trial‐eligible patients. Conclusions This analysis replicates the clinical benefit of ERC seen in EAST‐AFNET 4. The results support adoption of ERC as part of the management of recently diagnosed AF in the United States.
Influence of atrial fibrillation type on outcomes of ablation vs. drug therapy: results from CABANA
Abstract Aims Influence of atrial fibrillation (AF) type on outcomes seen with catheter ablation vs. drug therapy is incompletely understood. This study assesses the impact of AF type on treatment outcomes in the Catheter Ablation vs. Antiarrhythmic Drug Therapy for Atrial Fibrillation Trial (CABANA). Methods and results CABANA randomized 2204 patients ≥65 years old or <65 with at least one risk factor for stroke to catheter ablation or drug therapy. Of these, 946 (42.9%) had paroxysmal AF (PAF), 1042 (47.3%) had persistent AF (PersAF), and 215 (9.8%) had long-standing persistent AF (LSPAF) at baseline. The primary endpoint was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Symptoms were measured with the Mayo AF-Specific Symptom Inventory (MAFSI), and quality of life was measured with the Atrial Fibrillation Effect on Quality of Life (AFEQT). Comparisons are reported by intention to treat. Compared with drug therapy alone, catheter ablation produced a 19% relative risk reduction in the primary endpoint for PAF {adjusted hazard ratio [aHR]: 0.81 [95% confidence interval (CI): 0.50, 1.30]}, and a 17% relative reduction for PersAF (aHR: 0.83, 95% CI: 0.56, 1.22). For LSPAF, the ablation relative effect was a 7% reduction (aHR: 0.93, 95% CI: 0.36, 2.44). Ablation was more effective than drug therapy at reducing first AF recurrence in all AF types: by 51% for PAF (aHR: 0.49, 95% CI: 0.39, 0.62), by 47% for PersAF (aHR: 0.53, 95% CI: 0.43,0.65), and by 36% for LSPAF (aHR 0.64, 95% CI 0.41,1.00). Ablation was associated with greater improvement in symptoms, with the mean difference between groups in the MAFSI frequency score favouring ablation over 5 years of follow-up in all subgroups: PAF had a clinically significant −1.9-point difference (95% CI: −1.2 to −2.6); PersAF a −0.9 difference (95% CI: −0.2 to −1.6); LSPAF a clinically significant difference of −1.6 points (95% CI: −0.1 to −3.1). Ablation was also associated with greater improvement in quality of life in all subgroups, with the AFEQT overall score in PAF patients showing a clinically significant 5.3-point improvement (95% CI: 3.3 to 7.3) over drug therapy alone over 5 years of follow-up, PersAF a 1.7-point difference (95% CI: 0.0 to 3.7), and LSPAF a 3.1-point difference (95% CI: -1.6 to 7.8). Conclusion Prognostic treatment effects of catheter ablation compared with drug therapy on the primary and major secondary clinical endpoints did not differ consequentially by AF subtype. With regard to decreases in AF recurrence and improving quality of life, ablation was more effective than drug therapy in all three AF type subgroups. ClinicalTrials.gov Identifier NCT00911508
Catheter ablation of atrial fibrillation: recent advances and future challenges
Background: Pulsed field ablation (PFA) is a novel form of ablation using electrical fields to ablate cardiac tissue. There are only limited data assessing the feasibility and safety of this type of ablation in humans. Methods: PULSED AF (Pulsed Field Ablation to Irreversibly Electroporate Tissue and Treat AF; https://www.clinicaltrials.gov ; unique identifier: NCT04198701) is a nonrandomized, prospective, multicenter, global, premarket clinical study. The first-in-human pilot phase evaluated the feasibility and efficacy of pulmonary vein isolation using a novel PFA system delivering bipolar, biphasic electrical fields through a circular multielectrode array catheter (PulseSelect; Medtronic, Inc). Thirty-eight patients with paroxysmal or persistent atrial fibrillation were treated in 6 centers in Australia, Canada, the United States, and the Netherlands. The primary outcomes were ability to achieve acute pulmonary vein isolation intraprocedurally and safety at 30 days. Results: Acute electrical isolation was achieved in 100% of pulmonary veins (n=152) in the 38 patients. Skin-to-skin procedure time was 160±91 minutes, left atrial dwell time was 82±35 minutes, and fluoroscopy time was 28±9 minutes. No serious adverse events related to the PFA system occurred in the 30-day follow-up including phrenic nerve injury, esophageal injury, stroke, or death. Conclusions: In this first-in-human clinical study, 100% pulmonary vein isolation was achieved using only PFA with no PFA system–related serious adverse events. Graphic Abstract: A graphic abstract is available for this article.
Association Between Age and Outcomes of Catheter Ablation Versus Medical Therapy for Atrial Fibrillation: Results From the CABANA Trial
Background: Observational data suggest that catheter ablation may be safe and effective to treat younger and older patients with atrial fibrillation. No large, randomized trial has examined this issue. This report describes outcomes according to age at entry in the CABANA trial (Catheter Ablation versus Antiarrhythmic Drug Therapy for Atrial Fibrillation). Methods: Patients with atrial fibrillation ≥65 years of age, or <65 with ≥1 risk factor for stroke, were randomly assigned to catheter ablation versus drug therapy. The primary outcome was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Secondary outcomes included all-cause mortality, the composite of mortality or cardiovascular hospitalization, and recurrence of atrial fibrillation. Treatment effect estimates were adjusted for baseline covariables using proportional hazards regression models. Results: Of 2204 patients randomly assigned in CABANA, 766 (34.8%) were <65 years of age, 1130 (51.3%) were 65 to 74 years of age, and 308 (14.0%) were ≥75 years of age. Catheter ablation was associated with a 43% reduction in the primary outcome for patients <65 years of age (adjusted hazard ratio [aHR], 0.57 [95% CI, 0.30–1.09]), a 21% reduction for 65 to 74 years of age (aHR, 0.79 [95% CI, 0.54–1.16]), and an indeterminate effect for age ≥75 years of age (aHR, 1.39 [95% CI, 0.75–2.58]). Four-year event rates for ablation versus drug therapy across age groups, respectively, were 3.2% versus 7.8%, 7.8% versus 9.6%, and 14.8% versus 9.0%. For every 10-year increase in age, the primary outcome aHR increased (ie, less favorable to ablation) an average of 27% (interaction P value=0.215). A similar pattern was seen with all-cause mortality: for every 10-year increase in age, the aHR increased an average of 46% (interaction P value=0.111). Atrial fibrillation recurrence rates were lower with ablation than with drug therapy across age subgroups (aHR 0.47, 0.58, and 0.49, respectively). Treatment-related complications were infrequent for both arms (<3%) regardless of age. Conclusions: We found age-based variations in clinical outcomes for catheter ablation compared with drug therapy, with the largest relative and absolute benefits of catheter ablation in younger patients. No prognostic benefits for ablation were seen in the oldest patients. No differences were found by age in treatment-related complications or in the relative effectiveness of catheter ablation in preventing recurrent atrial arrhythmias. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00911508.
Generalizability of the EAST-AFNET 4 trial: assessing outcomes of early rhythm-control therapy in patients with atrial fibrillation
Abstract Background The Early Treatment of Atrial Fibrillation for Stroke Prevention Trial (EAST-AFNET 4) demonstrated clinical benefit of early rhythm-control therapy in patients with recently diagnosed atrial fibrillation (AF) and concomitant cardiovascular conditions (CHA2DS2-VASc-Score ≥2) compared to the current practice of limited rhythm-control therapy to improve AF-related symptoms. Purpose To evaluate the generalizability of the EAST-AFNET 4 trial in routine practice, we assessed the proportion of patients who would have met trial eligibility and examined the association between early rhythm-control and clinical outcomes. Methods Using a large US administrative database, we identified 109,739 patients with newly diagnosed AF from July 28th, 2011 to December 30th, 2016, the enrollment period of the EAST-AFNET 4 trial. Eligibility for trial inclusion was assessed based on inclusion criteria. Eligible patients were classified as either receiving early rhythm-control, i.e AF ablation and/or any antiarrhythmic drug therapy, within the first year after AF diagnosis (N=27,106) or patients not receiving early rhythm-control (N=82,633). The date 12 months after the first AF diagnosis was defined as the index date and the start of the follow up period. Propensity score overlap weighting was used to balance patients on 90 baseline characteristics. Cox proportional hazards regression was used to compare early rhythm-control with no early rhythm-control for the primary outcome of a composite end point of all-cause mortality, stroke, or hospitalization with the diagnoses heart failure or myocardial infarction. Results Eligible for the trial were 72.9% (82,633/109,739) of all patients with newly diagnosed AF. Early rhythm-control therapy was associated with a reduction in the composite end point in the overall cohort of patients (hazard ratio [HR] 0.85; 95% confidence interval [CI] 0.75–0.97; P=0.015) with largely consistent treatment effects between patients eligible or ineligible for the trial. The reduction of stroke risk associated with early rhythm-control therapy was found in the overall cohort (HR 0.66; 95% CI 0.47–0.93; P=0.017) and in the trial-eligible cohort (HR 0.67; 95% CI 0.45–0.98; P=0.041). Conclusion In a large health care data set, the majority of patients with newly diagnosed AF were eligible for the trial. Early rhythm-control therapy was associated with a 15% reduction in the composite end point of all-cause mortality, stroke, or hospitalization with the diagnoses heart failure or myocardial infarction, with the greatest benefit in the reduction of stroke risk. The treatment effect was consistent between patients eligible or ineligible for the trial. Patients in routine practice had higher rates of adverse outcomes than the trial, but the relative risk reduction with early rhythm-control therapy was similar. These data demonstrate the potential of early rhythm-control therapy to reduce outcomes in patients with AF. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): German Heart Foundation (Mit Fördermitteln der Deutschen Herzstiftung e.V.)