Feasibility, Safety, and Efficacy of Pulsed Field Ablation for Ventricular Arrhythmias: Insights From a Large Health System Registry in the United States
ABSTRACT Background Pulsed field ablation (PFA) is an emerging non‐thermal ablation modality with proven safety in atrial arrhythmia ablation. However, data on its performance for ventricular arrhythmias (VA) remain limited. Objective To evaluate the feasibility, safety, and efficacy of PFA for complex VA in a multicenter real‐world US registry. Methods This retrospective study included consecutive patients undergoing PFA for ventricular tachycardia (VT) or premature ventricular contractions (PVCs) at three Mayo Clinic centers (April 2024 to July 2025). The primary feasibility outcome was the successful delivery of PFA lesions to the intended target substrate. Primary efficacy outcomes included acute procedural success; sustained VT recurrence requiring implantable cardioverter‐defibrillator (ICD) shocks or multiple antitachycardia pacing therapies; and ≥ 80% reduction in PVC burden. Safety outcomes included procedural complications, valvular function, thromboembolic events, renal function, and conduction disturbances. Results Twenty‐six patients were included (13 PVC, 13 VT). Acute success was achieved in all VT ablations (69.2% complete; 30.8% partial) and in 92.3% of PVC ablations. Complications occurred in 11.5% of patients (transient LBBB [ n = 1] and vascular complications [ n = 2]). No thromboembolic events, intracardiac thrombus, or acute kidney injury were observed. Lesions near the mitral valve apparatus did not worsen mitral regurgitation, including in patients with pre‐existing valve disease. After a median follow‐up of 365 days, one patient experienced VT recurrence requiring ICD shocks. Estimated recurrence‐free survival after VT ablation was 61.5% at 12 months; 58.3% of PVC patients achieved ≥ 80% burden reduction. Conclusion PFA for VA appears feasible and acutely effective, with a low rate of procedure‐related complications. While acute success was high, long‐term outcomes were acceptable for VT ablation and relatively modest for PVC ablation, highlighting the need for continued refinement of technology and energy‐delivery strategies. Larger prospective studies are warranted.
Cardiac Resynchronization Therapy and Circulating Metabolomic Profile in Patients With Advanced Heart Failure
BACKGROUND: It is unknown whether cardiac resynchronization therapy (CRT) improves systemic metabolomic profile by enhancing left ventricular function. The observational cohort study aimed to investigate the effect of CRT on left ventricular ejection fraction (LVEF) and circulating plasma metabolites in patients who had heart failure with reduced LVEF. METHODS: We prospectively screened patients with ischemic cardiomyopathy and nonischemic cardiomyopathy who received CRT with a defibrillator for LVEF ≤35% according to current guidelines. Clinical assessment included echocardiography and device interrogation. Blood samples for metabolomic analysis were collected before CRT and at 6-month follow-up. Plasma was subjected to gas chromatography-mass spectrometry and 1 H nuclear magnetic resonance-based metabolomic analysis. RESULTS: Totally 92 patients were enrolled, with a mean age of 67.3±11.3 years (37.0% female). LVEF was significantly improved from 28.9±7.6% at baseline to 36.0±11.3% at 6 months ( P <0.001) and to 40.1±12.6% at 12 months ( P <0.001). After CRT, 42 metabolite features were significantly decreased compared with the baseline. The ketone bodies, including 3-hydroxybutyrate ( P <0.001) and acetone ( P =0.01), were reduced. A branched-chain amino acid, isoleucine, was also decreased after CRT ( P =0.01). These metabolomic changes were mainly observed in the nonischemic cardiomyopathy group, while the metabolomic profile in the ischemic cardiomyopathy group was characterized by enhanced amino acid oxidation and elevated levels of lactate and pyruvate. The improvement in LVEF positively correlated with the ratio of changes in ketone bodies and isoleucine. CONCLUSIONS: CRT may modulate the systemic plasma metabolomic profile, which correlated with improvement in left ventricular function in patients with severe heart failure with reduced ejection fraction.
Tirzepatide and the Incidence of Atrial Fibrillation in Adults With Overweight or Obesity: An Updated Meta‐Analysis of Randomized Controlled Trials
Background Tirzepatide is a dual agonist for glucose‐dependent insulinotropic polypeptide and glucagon‐like peptide‐1 receptors, with proven efficacy in weight loss and improvement in cardiovascular outcomes. However, the effects of tirzepatide on the incidence of atrial fibrillation in patients with overweight or obesity remain unclear. Methods PubMed, Embase, and Cochrane Library were searched for randomized controlled trials comparing tirzepatide versus placebo for individuals with overweight or obesity. Odds ratios (ORs) with 95% credible intervals (CrIs) were pooled using a Bayesian binomial‐normal hierarchical model, appropriate for rare‐event outcomes. Results Our meta‐analysis included 10 randomized controlled trials, including 6515 individuals, of whom 4491 (68.9%) were randomized to tirzepatide. The pooled OR was 2.20 (95% CrI, 0.81–6.75) for atrial fibrillation, 2.16 (95% CrI, 0.90–5.87) for atrial arrhythmia, and 1.84 (95% CrI, 1.04–3.90) for any arrhythmia. Conclusions Tirzepatide was not associated with atrial fibrillation or atrial arrhythmia. Although higher odds of overall arrhythmias were observed, event rates were low and the findings should be interpreted cautiously.
Large Language Models for PVC Localization: Proof of Concept or Clinical Tool?
Abstract Background Adults with congenital heart disease (ACHD) represent a rapidly expanding population with evolving mortality patterns. Despite improved survival, excess mortality persists. Objective To evaluate the incidence, causes, and predictors of mortality in a contemporary ACHD cohort. Methods We performed a retrospective cohort study of adults (≥18 years) first evaluated at Mayo Clinic from 2002–2023. Baseline clinical, imaging, and electrocardiographic data were analyzed. Vital status was determined using institutional records and the Accurint national mortality database. Kaplan-Meier analysis and Cox proportional hazard models were used to evaluate mortality and identify independent predictors of mortality Results A total of 7,678 ACHD patients were included, with median age of 36.8 years and median follow-up of 11.4 years. During 78,768 patient-years of follow-up, 1,116 patients died (median age at death 57.2 years), corresponding to an annual mortality rate of 1.4%. The cumulative rate of all-cause mortality at 5, 10, 15, and 20 years was 6.9%, 12.0%, 19.0%, and 26.2%, respectively. When stratified by CHD complexity, the annual death rate in patients with severe CHD (2.4%/year) was twice that of patients with moderate or mild CHD (both 1.2%/year). Older age and ACHD subtypes, specifically, cyanotic heart disease (HR 3.9, 95% CI 2.9–5.3) and Fontan physiology (HR 3.2, 95% CI 2.3–4.4), were strongly associated with increased mortality. Additional independent predictors included male sex, ventricular dysfunction, advanced NYHA class, prior heart failure hospitalization, hypertension, smoking, coronary artery disease, renal dysfunction, and abnormal hemoglobin levels. Cardiovascular causes accounted for 57.7% of deaths with known etiology, predominantly heart failure (48.9%) and sudden cardiac death (21.9%), while non-cardiovascular causes were driven mainly by infection and malignancy. Conclusions In this large contemporary ACHD cohort, mortality was driven by ventricular dysfunction, heart failure, and systemic end-organ involvement in addition to the underlying congenital anatomy. Both cardiovascular and non-cardiovascular causes contributed significantly to mortality. These findings underscore the need for comprehensive multidisciplinary ACHD care focused on early recognition of cardiac functional decline, management of acquired comorbidities, and end-organ dysfunction.
Physiology-guided cardioneuroablation for vagally mediated syncope and functional bradyarrhythmias
Abstract Background Vagally mediated syncope and functional bradyarrhythmias can cause recurrent symptoms, injury and a need for permanent pacing, yet standard therapies do not address the underlying autonomic reflex. Cardioneuroablation (CNA) targets this mechanism, but adoption has been limited by uncertainty about patient selection, procedural endpoints and durable outcomes. Methods We studied 95 consecutive patients with vagally mediated syncope (n=78) or functional bradyarrhythmia (n=17) who underwent CNA at a single center by a single lead operator under a uniform, prospectively maintained protocol. Extracardiac vagal stimulation (ECVS) was performed before and after ablation to confirm vagally mediated sinus or atrioventricular (AV) nodal responses and to verify their attenuation. Outcomes through 1 year included clinical recurrence, quality of life, pacing burden and pacemaker extraction. Results Before ablation, ECVS provoked sinus pauses in 95.8% of patients and AV block in 91.6%; after ablation, sinus pauses were abolished in every patient and residual AV block was present in 4.2%. One-year freedom from recurrent syncope and from bradyarrhythmia-related events was 93.8% and 94.1%. Syncope burden fell from a median of 2.7 episodes per year to none, and disease-specific quality of life improved substantially (P<0.001). Among patients with pre-existing devices, atrial pacing burden fell from a median of 22% to 0%. There were no strokes, deaths or myocardial infarctions. Conclusions In this single-center cohort, physiology-guided CNA was associated with durable symptom control, improved quality of life and reduced pacing across vagally mediated bradyarrhythmia syndromes. Multicenter controlled studies are needed to confirm these findings.
The blanking interval after atrial fibrillation ablation: time for reassessment with pulsed field energy—Authors’ reply
ABSTRACT Background Patients with end‐stage renal disease (ESRD) undergoing dialysis have an increased risk of pacemaker‐related complications due to limited vascular access and increased susceptibility to infection. Leadless pacemakers (LPMs) may mitigate these risks compared with conventional transvenous pacemakers (TPMs), but long‐term comparative data in this population remain limited. Methods We conducted a retrospective cohort study using the TriNetX Research Network, including adults (≥ 18 years) with ESRD on dialysis who underwent LPM or TPM implantation between May 2016 and December 2020. Propensity score matching (1:1) was performed using demographics and comorbidities. Outcomes assessed over up to 5 years included all‐cause hospitalization, heart failure hospitalization, device re‐intervention, device‐related complications, infection‐related hospitalization, pacemaker‐induced cardiomyopathy, and all‐cause mortality. Results After matching, 901 patients were included in each group with well‐balanced baseline characteristics. LPM implantation was associated with a significantly lower risk of device re‐intervention compared with TPM (4.1% vs. 9.3%; hazard ratio [HR] 0.44; 95% confidence interval [CI] 0.28–0.69; p < 0.01). There were no significant differences between groups in all‐cause hospitalization (65.5% vs. 68.3%; p = 0.22), heart failure hospitalization (26.9% vs. 30.2%; p = 0.13), all‐cause mortality (37.5% vs. 35.3%; p = 0.34), device‐related complications (14.5% vs. 14.3%; p = 0.94), infection‐related hospitalization (1.6% vs. 2.1%; p = 0.35), or pacemaker‐induced cardiomyopathy (9.0% vs. 8.6%; p = 0.66). Conclusion In a large, propensity‐matched cohort of patients with ESRD on dialysis, LPMs were associated with fewer device re‐interventions and comparable long‐term clinical outcomes compared with TPMs.
Clinical Outcomes of Catheter Ablation for Atrial Fibrillation in Patients With Hypertrophic Cardiomyopathy
ABSTRACT Background Atrial fibrillation (AF) is common in patients with hypertrophic cardiomyopathy (HCM) and is associated with increased morbidity, heart failure (HF) exacerbations, and adverse long‐term outcomes. Although catheter ablation is an established rhythm‐control strategy, data comparing its long‐term clinical outcomes with anti‐arrhythmic drug (AAD) therapy in patients with HCM remain limited. Objective To compare long‐term clinical outcomes of catheter ablation versus medical therapy with AADs in patients with HCM and AF. Methods We conducted a retrospective cohort study using the TriNetX Research Network, a global federated database of electronic health records. Adult patients with HCM and AF between January 2010 and December 2020 were identified and stratified according to treatment with catheter ablation or AAD therapy. Outcomes included all‐cause mortality, HF exacerbations, AAD‐related adverse events, all‐cause hospitalization, ischemic stroke, repeat ablation, need for cardioversion, need for long‐term AAD use, and atrioventricular nodal ablation. A 1:1 propensity score matching (PSM) analysis was performed to balance baseline characteristics. Kaplan–Meier survival analysis and Cox proportional hazards models were used to estimate hazard ratios (HRs). Results After PSM, 3144 patients were included (1572 in each cohort) with a mean follow‐up of approximately 3.4 years. Catheter ablation was associated with lower all‐cause mortality compared with AAD therapy (9.5% vs. 14.8%; HR: 0.60; 95% CI: 0.49–0.74; p < 0.001). Ablation was also associated with reduced risk of HF exacerbations (38.4% vs. 43.3%; HR: 0.79; 95% CI: 0.71–0.88; p < 0.001) and fewer AAD‐related adverse events (8.4% vs. 11.2%; HR: 0.71; 95% CI: 0.55–0.93; p = 0.011). Rates of all‐cause hospitalization (HR: 0.93; p = 0.11) and ischemic stroke (HR: 0.78; p = 0.10) were similar between groups. Conclusion In this large real‐world cohort of patients with HCM and AF, catheter ablation was associated with lower mortality, reduced HF hospitalizations, and decreased AAD therapy‐related adverse events, as compared with medical therapy. These findings suggest that catheter ablation may provide meaningful clinical benefits in selected patients with HCM and AF, although prospective studies are needed to confirm these observations.
Abstract WE404: Trends in Survival after Atrial Fibrillation in a Midwestern Community
Background: Contemporary data on trends in survival after incident atrial fibrillation (AF) are limited. Methods: Residents of a 27-county area in southern Minnesota and western Wisconsin with new-onset atrial fibrillation or atrial flutter between 2013 and 2023 were identified. An electronic algorithm requiring 1 inpatient code or 2 outpatient codes separated by >7 days but within 1 year was used to define AF. Patients were followed for all-cause mortality through March 31, 2025. Standardized mortality ratios of observed versus expected survival were calculated, and time trends in survival were examined using Cox regression adjusting for demographics, cardiovascular risk factors, comorbid conditions, and area-level measures of socioeconomic status and rurality. Results: There were 44,930 individuals identified with incident AF from 2013-2023 (56.4% male; mean (SD) age 72.8 (13.5) years; 95.8% were non-Hispanic white). Within the first 90 days, the risk of all-cause mortality was greatly elevated compared with individuals of a similar age and sex distribution in the general population (standardized mortality ratios 12.6, 95% CI, 12.1-13.0 and 3.8, 95% CI, 3.6-4.0 for the first 30 days and 31 to 90 days after diagnosis, respectively). This excess risk was observed for all age groups but was greatest in the youngest age group (standardized mortality ratios among 18-64 year olds for the first 30 days: 49.9, 95% CI, 44.6-55.7 and 31 to 90 days: 11.1, 95% CI: 9.4-13.1; Figure ). In the youngest age group, the excess risk persists through 5 years post AF, however, in the oldest age group the excess risk only persisted through 1 year. Survival within the first 90 days improved over the study period (adjusted hazard ratio [aHR], 0.88; 95% CI, 0.79-0.99 for 2023 vs 2013); likewise, among 90-day survivors, survival improved between 2013 and 2023 (aHR,0.82; 95% CI, 0.76-0.88). These trends were driven by improvements in the younger age groups, particularly for death among 90-day survivors (aHR for 18-64 years, 0.66, 95% CI, 0.52-0.83; 65-74 years: 0.77, 95% CI: 0.65-0.90; 75-84 years, 0.84, 95% CI: 0.75-0.95; 85+ years, 0.99, 95% CI: 0.98-1.01). Conclusion: In a Midwestern community, the excess risk of death is high within the first 90 days after incident AF. Furthermore, survival after AF has improved between 2013 and 2023, with the improvement greatest in younger age groups.