Mark T. Mills

This review summarizes current knowledge on the coexistence of obstructive sleep apnoea and atrial fibrillation. A narrative review of the literature was conducted to identify relevant clinical and mechanistic studies. Obstructive sleep apnoea is highly prevalent among patients with atrial fibrillation and adversely affects rhythm-control outcomes. The interplay between these two conditions is of significant clinical importance, as obstructive sleep apnoea contributes to the development and progression of arrhythmias through multiple pathophysiological mechanisms: mechanical atrial stretch, immune activation and low-grade inflammation, autonomic dysregulation, oxidative stress, and systemic hypoxia. These mechanisms promote the initiation, maintenance, and treatment resistance of atrial fibrillation. Multimodal management strategies aimed at this harmful interplay may improve outcomes in patients with atrial fibrillation and include lifestyle and dietary interventions, pharmacometabolic therapies, particularly glucagon-like peptide-1 receptor agonists, continuous positive airway pressure therapy, and, in selected cases, catheter ablation strategies, potentially extended to the ganglionated plexi. Collectively, these approaches may contribute to the restoration and maintenance of sinus rhythm.

Background: Sex-based differences in atrial fibrillation (AF) symptom burden and response to rhythm control strategies are recognised. Whether female and male patients differ in escalation to atrioventricular (AV) node ablation after AF catheter ablation remains uncertain. Objective: To evaluate sex differences in AV node ablation following AF ablation in a large real-world cohort. Methods: Adults undergoing first-time AF ablation between 2015 and 2024 were identified from a global federated research network. Patients with prior AV node ablation or cardiac implantable electronic devices were excluded. Female and male patients were compared before and after 1:1 propensity score matching for demographics, AF type, heart failure phenotype, co-morbidities, medication use and prior cardioversion. The primary outcome was AV node ablation within 5 years. Secondary outcomes included repeat AF ablation, electrical cardioversion and all-cause mortality. Pre-specified falsification endpoints (pneumonia and intestinal obstruction) were assessed to evaluate residual confounding. Results: Before matching (28,004 female; 52,137 male), AV node ablation occurred in 2.5% of female and 1.1% of male patients (risk ratio [RR] 2.31, 95% CI 2.07–2.58). After matching (24,377 female and 24,377 male), baseline characteristics were well balanced, yet AV node ablation remained more frequent in female than male patients (2.3% vs. 1.2%; RR 1.94, 95% CI 1.68–2.23). Female patients were also more likely to undergo repeat AF ablation (14.7% vs. 14.1%; RR 1.04, 95% CI 1.01–1.08), whilst mortality was modestly lower (4.5% vs. 4.9%; RR 0.91, 95% CI 0.84–0.99; p = 0.027). Falsification endpoints did not differ between groups after matching. Conclusion: Female patients were more likely than male patients to undergo AV node ablation following AF ablation despite robust adjustment, suggesting important sex-based differences in downstream AF management.

Pacing-induced cardiomyopathy (PICM) is a recognized complication of pace-and-ablate therapy. Early identification of patients at risk may allow tailored strategies, including upfront biventricular or conduction system pacing. This study aimed to identify predictors of PICM in patients undergoing pace-and-ablate therapy, combining expert consensus with clinical validation. A three-round Delphi process involving 12 electrophysiologists prioritized candidate predictors of PICM. Consecutive patients undergoing atrioventricular node ablation with non-cardiac resynchronization therapy (CRT) devices at Liverpool Heart and Chest Hospital (2015–2019) were retrospectively analysed. The primary endpoint was PICM, defined as ≥10% reduction in left ventricular ejection fraction (LVEF) to <50%, adjudicated by two independent cardiologists. Cox regression was used to identify independent predictors. The Delphi process prioritized baseline LVEF, intrinsic and paced QRS duration, RV lead position, and key comorbidities. Among 658 ablation patients, 323 (median age 76 years, 67% female) had non-CRT devices. Over a median follow-up of 192 days (IQR, 63–1003 days), 33 patients (9.8%) developed PICM. In multivariable analysis, RV free wall vs. septal lead position [hazard ratio (HR) 4.896, 95% confidence interval (CI) 1.263–18.973, P = 0.022], intrinsic QRS duration (HR 1.247 per 10 ms, 95% CI 1.064–1.462, P = 0.006), independently predicted PICM. Exploratory analyses suggested that higher intrinsic QRS duration was associated with increased PICM risk; however, these findings were based on a small number of events and should be interpreted with caution. Intrinsic QRS duration and free wall RV lead position independently predict PICM in pace-and-ablate patients. These findings support early risk stratification and may guide personalized pacing strategies.

Aims: Disparities in arrhythmia care are increasingly recognized, yet remain incompletely characterized across the patient pathway. This European Heart Rhythm Association (EHRA) survey explored clinician-reported perceptions of inequity across diagnosis, pharmacological management, procedural referral, and follow-up. Methods and results: A 30-question survey was disseminated via the EHRA between November 2025 and January 2026, with 212 responses from professionals across 35 countries. Respondents were predominantly consultant electrophysiologists (67.5%), with 39.6% identifying as female. Most (68.4%) reported no prior training in equity or inclusive care. Across the arrhythmia care pathway, disparities were most frequently attributed to patient vulnerability, particularly cognitive impairment (72.5%), age >80 years (63.8%), and mental health disease (61.3%). Differences related to socioeconomic status, language, and other social factors were also commonly reported. Female sex and minority ethnic background were each reported to influence care in 24.1% of responses. Age >80 years was consistently identified as the strongest determinant of disparities in referral, diagnosis, and outcomes, influencing referral for arrhythmia evaluation (65.8%), catheter ablation (77.9%), and outcomes following ablation (68.1%). Socioeconomic and ethnic factors showed more modest but consistent effects, while sex-based differences were less frequently reported. However, female respondents were more likely than male respondents to report delayed referral (female respondents: 41.8%; male respondents: 19.8%) and late or incorrect diagnosis (49.4 vs. 15.8%) in female patients, as well as delayed referral for catheter ablation (36.5 vs. 10.3%) and device implantation (23.0 vs. 7.0%). Only one-third of respondents (33.3%) felt that current international guidelines adequately address diversity, equity, and inclusion in arrhythmia care. Conclusion: Clinicians perceive disparities in arrhythmia care across multiple patient and social factors. Whilst age and vulnerability were most frequently perceived to influence care, sex and ethnicity were also recognized by a substantial proportion of respondents. Perceptions varied according to respondent characteristics, with female clinicians more likely to report disparities amongst female patients. Limited training and institutional frameworks highlight opportunities for targeted interventions.

Aims: We sought to systematically catalogue and compare outcomes definitions across prospective clinical trials and registries evaluating ablation in VT to assess the impact of heterogeneous definitions on reported outcomes. Methods and results: A systematic review (PROSPERO: CRD 42024595265) was performed in accordance with PRISMA guidelines. We searched for prospective studies from January 2000 to November 2024. Randomized trials, single-arm feasibility studies, and prospective registries involving ≥10 patients undergoing VT ablation were included. Study outcomes and their definitions were extracted and categorized. Pooled analyses were performed for comparable randomized trial subgroups, and meta-regression evaluated the effect of VT outcome definitions on reported success and complications. Fifty-nine studies were included: 15 randomized trials, 6 feasibility studies, and 38 prospective studies/registries. Definitions of acute procedural success varied, with most using acute clinical VT non-inducibility and others using only elimination of the clinical VT. VT recurrence was the most frequently reported long-term outcome; however, definitions differed markedly (VT recurrence or recurrence causing device therapy). Pooled analysis of prophylactic ablation vs. delayed ablation showed reduced VT recurrence (HR 0.63, 95% CI: 46–0.86) but no difference in hospitalization or mortality. Meta-regression demonstrated that an outcome of any VT recurrence yielded a higher failure rate of 51.0% compared to stricter definitions, such as VT-causing therapy at 37.3% or VT-causing shock only at 23.4% (P = 0.002). Safety outcomes were inconsistently reported. Conclusion: Outcome definition in VT ablation trials showed substantial heterogeneity, limiting cross-trial comparability and meta-analytic synthesis. Development of a minimum set of standardized outcomes for VT ablation may improve consistency and clinical interpretability of VT trials.

Aims: Pulsed field ablation (PFA) has rapidly emerged as a non-thermal ablation technology for pulmonary vein isolation (PVI), with an unprecedented adoption across Europe. The aim of this survey was to characterize current practice patterns. Methods and results: The European Heart Rhythm Association (EHRA) Scientific Initiatives Committee designed a 30-item questionnaire addressing temporal adoption of PFA, pre-, intra-, and post-procedural workflows, and future perspectives. The survey was distributed between April and June 2025. A total of 216 responses were obtained from 43 countries. At the time of the survey, 23% of respondents had not yet initiated a PFA programme. Overall, PFA is now used in half (49%) of first atrial fibrillation (AF) ablation procedures. Adoption was significantly higher in high-volume centres and ‘Western European’ countries. The primary driver for adoption was time efficiency (60%). Intra-procedural workflows showed marked heterogeneity: approximately half of the operators relied exclusively on fluoroscopy without any intra-procedural imaging/mapping. Additional ablation lesions beyond PVI were common, with one-third employing standardized PVI+ protocols in persistent AF, most frequently posterior wall isolation. General anaesthesia and deep sedation were used in equal proportions. Conclusion: This EHRA survey demonstrates both rapid implementation and significant heterogeneity in PFA use across Europe. Standardized protocols and prospective studies are needed to define best practices.