Luigi Di Biase

The role of atrial fibrillation (AF) ablation in the management of heart failure with preserved ejection fraction (HFpEF) remains an under investigated issue with no robust clinical trials data. This controversy reviews the evidence for and against AF ablation in this complex condition from two different perspectives reviewing mechanistic and observational evidence aswell as proposing future directions for research in the field.

Background: Registry studies from 2000–2010 demonstrated underutilization of primary prevention ICD therapy. As heart failure therapies have reduced sudden cardiac death, investigators have questioned guidelines derived from trials conducted two decades prior, particularly in non‐ischemic cardiomyopathy (NICM) and elderly subgroups. We characterized contemporary referral determinants, decision‐making processes, and outcomes of primary prevention ICD therapy in a diverse, under‐represented population. Methods: In this retrospective single‐center cohort study, we reviewed records of all patients meeting Class I criteria for primary prevention ICD in 2019. Multivariable logistic regression identified factors associated with ICD referral, and time‐varying Cox models compared all‐cause mortality by implantation status through 2022. Results: Of 559 eligible patients, 345 (62%) were referred and 227 (41%) underwent implantation. Referral was associated with male gender, care coordination by a cardiologist rather than a generalist, and lower social vulnerability index (SVI) score. No decision‐making rationale was documented for a plurality of non‐referred and non‐implanted patients; documented rationales identified potential intervention targets. ICD implantation was not associated with all‐cause mortality (aHR 0.74, 95% CI 0.49–1.12). In exploratory analyses stratified by cardiomyopathy type, implantation was associated with lower mortality in ischemic cardiomyopathy (aHR 0.51, 95% CI 0.27–0.95) but not in NICM (aHR 1.11, 95% CI 0.63–1.95). Conclusion: Many eligible patients are never referred for ICD therapy. Female gender, generalist care coordination, and high SVI were associated with non‐referral. The exploratory association of implantation with lower mortality in ischemic cardiomyopathy was not significant in propensity score overlap‐weighted analyses. The NICM estimate was imprecise.

Pulsed field ablation has rapidly reshaped the landscape of atrial fibrillation ablation by offering a nonthermal, tissue-selective alternative to conventional thermal energy. This review highlights the scientific foundations, preclinical evidence, and engineering advances that established pulsed field ablation as a safer, faster, and more precise technology. We discuss how irreversible electroporation achieves myocardial selectivity, the pivotal studies that confirmed preservation of nearby structures, and the evolution of modern catheter systems designed for efficient and durable lesion creation. As pulsed field ablation platforms continue to mature, they are redefining procedural safety standards and expanding therapeutic possibilities in cardiac electrophysiology.

BACKGROUND: The variable loop circular catheter has been shown to be a safe, effective pulsed field ablation catheter for atrial fibrillation treatment. After the commercial launch of the initial waveform (Seq1), a new waveform (Seq2 _{30 mL/min} ) was developed that reduces electrode surface temperature and ablation delivery time (20–3.8 seconds). This study compares the safety and efficacy of Seq1 versus Seq2 across 2 irrigation rates and 2 dosing conditions. METHODS: Twenty-four Yorkshire pigs were treated with pulsed field ablation using the variable loop circular catheter. Subjects were randomized into 3 pulse recipe/irrigation arms (Seq1 _{4 mL/min} , Seq1 _{30 mL/min} , and Seq 2 _{30 mL/min} ). Each group was split into a 1× nominal and a 2×-dose group, resulting in 6 total study groups. Animals were monitored for 28±2 days postablation for follow-up remapping procedures before euthanization. Gross necropsy and histopathology were performed on day 28±2. RESULTS: In all groups, 100% acute and chronic pulmonary vein isolation effectiveness was observed, as indicated by transmural, circumferential, pulmonary vein lesions with no evidence of collateral injury. Transmurality in the left atrial appendage, LA roof, and posterior wall was 75% to 100% across all groups and absent at the mitral isthmus. No catheter thrombus/char was observed at Seq2 _{30 mL/min} or Seq1 _{30 mL/min} . With Seq1 _{4 mL/min} , thrombus/char occurred in 25% (1×) and 100% (2×). Hemolysis and myocardial injury marker changes were similar between all groups, with a notable increase in the 2× groups. On echocardiography, Seq2 _{30 mL/min} microbubbles were rated as few or none, while Seq1 _{4 mL/min} and Seq1 _{30 mL/min} were mostly rated moderate or shower. CONCLUSIONS: Consistently durable pulmonary vein isolation was observed across all groups, including Seq1 _{4 mL/min} , Seq2 _{30 mL/min} , and Seq1 _{30 mL/min} across both dosing conditions. Seq2 _{30 mL/min} was associated with a reduced ablation delivery time (3.8 seconds), zero catheter thrombus formation, and few microbubbles. Higher irrigation flow in Seq1 _{30 mL/min} also mitigated catheter thrombus formation but did not reduce microbubble generation.

The subcutaneous implantable cardioverter-defibrillator and extravascular implantable cardioverter-defibrillator do not require intravascular, intracardiac, or epicardial leads, making them attractive alternatives to transvenous implantable cardioverter-defibrillators in patients without bradycardia pacing or cardiac resynchronization therapy indications. These systems are especially useful for patients with venous access challenges and those at risk for endovascular infections, including patients with renal failure or those who are immunocompromised. Women with prior or anticipated breast surgery, such as mastectomy or breast reconstruction surgery, or those who are lactating present unique anatomic, procedural, and post-operative quality-of-life considerations. This commentary provides a practical, scenario-based framework for managing this unique patient group. Key considerations include individualized incision and pulse generator planning, proactive multidisciplinary coordination, procedure-specific management, and shared decision-making in patients with prior or anticipated breast augmentation or reduction, pregnancy, lactation, mastectomy, radiation therapy, and breast imaging.

Aims: Intracardiac echocardiography (ICE) facilitates left atrial (LA) reconstruction during atrial fibrillation (AF) ablation. The artificial intelligence–based CARTOSOUND FAM (AIFAM) module enables automated three-dimensional LA reconstruction without the need for a dedicated pre-ablation mapping catheter. While this workflow has been described previously in radiofrequency ablation, its application and outcome in pulsed field ablation (PFA) remain limited. The objective of this study is to evaluate the feasibility, safety, and arrhythmia-free outcomes of a no-pre-mapping AIFAM-guided workflow during PFA using the variable-loop circular catheter (VLCC). Methods and results: Patients undergoing PFA AF ablation using VLCC were screened and those using AIFAM-guided ablation without pre-map were included in the analysis. The LA shell was created using the AI-based ICE module from the right atrium without the need for a LA mapping catheter and was used as the only reference shell for PFA energy delivery. Baseline demographics, AF subtype, comorbidities, procedural details, and follow-up outcomes were analysed. Recurrence was assessed using a 60-day blanking period and Kaplan–Meier survival analysis. A total of 412 patients underwent AF ablation using VLCC during the study period. Among them, 210 patients (mean age 68.1 ± 10.2 years; 54.8% male) underwent AIFAM-guided ablation without pre-map and were analysed. Atrial fibrillation subtype was paroxysmal in 52% and non-paroxysmal in 48%. Concomitant AF ablation and left atrial appendage occlusion (LAAO) were performed in 76 patients (36%). The mean CHA2DS2-VASc score was 3.4 ± 1.7, and the mean left ventricular ejection fraction was 56.2 ± 11.1%. All patients underwent pulmonary vein isolation, with additional PF lesions including posterior wall isolation in 87.5% and superior vena cava ablation in 60.5%. Skin-to-skin procedure time and LA dwell time were 78.8 ± 29.1 min and 47.1 ± 18.8 min for ablation alone and 87.3 ± 22.9 min and 54.6 ± 13.0 min for concomitant AF ablation and LAAO. Acute procedural success was achieved in 100% of cases. One acute non-catheter-related vascular complication (0.5%), and no late complications were documented. Among 184 patients with at least one follow-up, freedom from arrhythmia survival after the 60-day blanking was 77.7% in paroxysmal AF and 71.8% in non-paroxysmal AF at 270 days. Conclusion: AIFAM enables safe and reliable LA reconstruction for successful PFA ablation, including concomitant AF ablation and LAAO using VLCC, and reduces the need for pre-ablation mapping in select patients undergoing index ablation. This strategy demonstrated high acute success, low complication rates, and favourable arrhythmia freedom in a contemporary cohort.