Antonio Dello Russo

Aims: Patients with left atrial appendage (LAAO) devices are increasingly referred for atrial fibrillation (AF) ablation, yet anticoagulation strategies remain uncertain. The goal of this study was to evaluate the safety and efficacy of catheter ablation for AF in patients with pre-existing LAAO devices and to describe patterns in anticoagulation management after ablation in this unique population. Methods and results: We collected data from 14 centres worldwide on patients with prior LAAO devices undergoing AF ablation. Each site provided clinical characteristics, procedural details, and information on complications and arrhythmia outcomes. Data were aggregated and analysed centrally to evaluate procedural safety, efficacy, and variability in management strategies. A total of 198 patients (age 70 years, 37% female, 42% paroxysmal AF) with prior LAAO were included. Ablation was performed a median of 271 days after LAAO. After ablation, 84% of patients were on oral anticoagulation (OAC), most commonly for 2–3 months. Bleeding complications on OAC occurred in 6.7% of patients at a median of 20 (13, 70) days after ablation. Stroke or TIA occurred in five patients (2.6% of cases) within the follow-up period with two occurrences (1% of cases) the day after ablation. There were two cases of new or worsened peri-device leak after ablation. Conclusion: In a large, international registry of patients undergoing catheter ablation for AF with pre-existing LAAO devices, ablation was feasible, and device related complications were rare. Despite higher bleeding risk in an LAAO population, 84% of patients with prior LAAO tolerated short-term OAC post-ablation with bleeding events at expected rates for this population.

Aims: Evidence supporting the use of pulsed field ablation (PFA) for ventricular arrhythmia (VA) ablation remains limited and heterogeneous, and the relationship between preclinical lesion characteristics and clinical outcomes is incompletely defined. We sought to systematically summarize preclinical lesion metrics and clinical outcomes of ventricular PFA. Methods and results: We performed a systematic review and meta-analysis of preclinical and clinical studies of ventricular PFA. Preclinical studies reporting lesion depth or transmurality and clinical studies detailing procedural efficacy and safety were included. Random-effects models were used to pool lesion characteristics and clinical outcomes. Seventy-five studies were included (33 preclinical, 43 clinical; 355 patients). In preclinical models, mean lesion depth was 5.96 mm(95%CI, 5.07–6.84) in healthy endocardium and 5.19 mm (95%CI, 2.58–7.79) in healthy epicardium. Notably, lesion depth was quantitatively similar in models of scarred myocardium (5.96 mm; 95%CI, 5.39–6.53). Lesion transmurality was variable in healthy tissues (32%; 95%CI, 15–52%) but higher within scar (53%; 95%CI, 36–70%). Consistently, lesion depth was similar between PFA and RF in healthy myocardium, but greater with PFA in scarred models (within-study mean depth difference, 2.09 mm; 95%CI, 0.84–3.34). Greater contact force, repeated applications, and higher energy/duration settings were associated with increased lesion depth. Clinically, acute success was high for both premature ventricular complexes (PVCs,90%; 95%CI, 83–96%) and ventricular tachycardia (VT;92%; 95%CI, 87–96%) in studies with ≥3patients. Over a mean follow-up of approximately 5months, recurrence rates were 19% (95%CI, 12–28%) for PVCs and 21% (95%CI, 10–35%) for VT. The overall complication rate was 10% (95%CI, 5–17%) in studies with ≥3patients, with coronary artery spasm and conduction disturbances representing the most frequent adverse events. Conclusion: Ventricular PFA demonstrates high acute efficacy and encouraging mid-term outcomes, supported by preclinical evidence of favourable lesion penetration within scarred myocardium. Safety considerations-particularly coronary and conduction system effects-and the heterogeneity of preclinical evidence highlight the need for further investigation.

Background: The most appropriate management of glucose-lowering therapies in patients exposed to iodinated contrast media (ICM) is still debated. The recent development of antidiabetic drugs that improve cardiovascular and renal outcomes leads to questions regarding their impact on the risk of contrast-associated acute kidney injury (CA-AKI). The present study aimed to assess the effect of different glucose-lowering therapies on the rate of CA-AKI among patients undergoing coronary angiography and/or angioplasty. Methods: Diabetic patients exposed to ICM for coronary procedures were retrospectively identified and divided according to the strategy for the management of diabetes mellitus. The use of a new antidiabetic drug (NAD) was defined for patients treated with SGLT2-I, DDP4-I or GLP-1 receptor agonists on admission. The primary endpoint was the occurrence of CA-AKI within 72 h after contrast medium exposure. Results: We included 462 patients with diabetes mellitus, 51.5% treated with insulin, 44.4% treated with metformin and 50.9% receiving NAD. Among them, 48 (10.4%) experienced CA-AKI. Patients experiencing acute renal injury were more often treated with calcium channel blockers (p = 0.04) and diuretics (p = 0.004), and less often P2Y12 inhibitors (p = 0.04), and presented lower levels of hemoglobin (p = 0.02). Patients receiving NADs displayed a significantly lower occurrence of CA-AKI (33.3% vs. 53.6%, p = 0.009), mainly for those treated with SGLT2-I. On the contrary, patients treated with sulfonylureas and meglitinides displayed a significant increase in the rate of CA-AKI (10.4% vs. 3.9%, p = 0.05). The results were confirmed via multivariable analysis, with NADs and diuretics emerging as the only independent predictors of CA-AKI (NAD: adjusted OR = 0.42 [0.21–0.81], p = 0.01; diuretics: adjusted OR = 2.22 [1.14–4.35], p = 0.02). The independent predictors of CA-AKI were the use of NADs (adjusted OR = 0.45 [0.24–0.86], p = 0.02) and diuretics (adjusted OR = 2.57 [1.33–4.97], p = 0.005). Conclusions: Among patients with diabetes mellitus undergoing coronary angiographic procedures, the use of diuretics, sulfonylureas and meglitinides is associated with an increased occurrence of CA-AKI, whereas the rate of events was significantly lower among users of new antidiabetic drugs and especially SGLT2-I.

Background: Despite being the most effective option for maintaining sinus rhythm, atrial fibrillation (AF) catheter ablation reaches few patients. For this reason, identifying candidates with the highest likelihood of success or individualizing counselling to a specific patient to improve procedural outcome could enhance clinical benefits and cost-effectiveness. Objective: To integrate machine learning (ML) into an outcome prediction model based on a large cohort of AF patients undergoing pulsed field ablation (PFA). Methods: Consecutive AF patients undergoing transcatheter PFA between June 2022 and December 2024 were prospectively enrolled in the ATHENA registry. All procedures were performed with a penta-splines 12F over-the-wire PFA catheter (FARAWAVE™, Boston Scientific). Clinical and procedural variables were collected to train five predictive models estimating 1 year arrhythmic recurrence; model interpretability was assessed using SHAP (SHapley Additive exPlanations) analysis. Results: The study included 1688 AF patients with a median follow-up of 365 days (interquartile range 202-393), arrhythmic recurrence occurred in 314 patients (18.6%). The Boruta algorithm identified diagnosis-to-ablation time (DAT), CHA₂DS₂-VASc score, age, and body mass index (BMI) as most significant predictors. Among the five ML models developed to predict 1 year arrhythmic recurrence probability, Random Forest achieved the best performance (AUC = 0.75, 95% CI 0.69-0.82). SHAP analysis confirmed DAT, BMI, and indexed left atrial volume as major contributors to recurrence. Conclusion: This is the first ML model exclusively trained and validated on AF patients undergoing PFA providing actionable insights for personalized treatment planning. Routine use of the model holds the potential to optimize patient selection and improve procedural outcome, supporting individualized counselling and outcome-driven care pathways, moving from static to interactive risk prediction. Clinical Trial Registration: Advanced TecHnologies For SuccEssful AblatioN of AF in Clinical Practice (ATHENA). URL: http://clinicaltrials.gov/ Identifier: NCT05617456

Pulsed field ablation has emerged as a novel non-thermal treatment modality with a distinct safety profile for the interventional treatment of atrial fibrillation. By inducing irreversible electroporation, pulsed field ablation achieves myocardial ablation while preserving surrounding structures such as nerves, vasculature, and the oesophagus. This European Heart Rhythm Association of the European Society of Cardiology scientific statement, endorsed by major international societies, reviews the biophysics, technology, clinical evidence, workflow, safety, and training aspects of pulsed field ablation. Randomized trials demonstrate comparable efficacy to radiofrequency and cryoballoon ablation, with advantages in safety and efficiency. The statement provides practical advice for clinical implementation and operator training and identifies key gaps in evidence and priorities for future research and innovation.