Background: High-frequency low-tidal-volume (HFLTV) ventilation is a safe and cost-effective strategy that improves catheter stability, first-pass pulmonary vein isolation, and freedom from all-atrial arrhythmias during radiofrequency catheter ablation (RFCA) of paroxysmal and persistent atrial fibrillation (AF). However, the incremental value of adding rapid-atrial pacing (RAP) to HFLTV-ventilation has not yet been determined. Objective: To evaluate the effect of HFLTV-ventilation plus RAP during RFCA of paroxysmal AF on procedural and long-term clinical outcomes compared to HFLTV-ventilation alone. Methods: Patients from the REAL-AF prospective multicenter registry, who underwent RFCA of paroxysmal AF using either HFLTV+RAP (500-600 msec) or HFLTV ventilation alone from April 2020 to February 2023 were included. The primary outcome was freedom from all-atrial arrhythmias at 12-month follow-up. Secondary outcomes included procedural characteristics, long-term clinical outcomes, and procedure-related complications. Results: A total of 545 patients were included in the analysis (HFLTV+RAP=327 vs. HFLTV=218). There were no significant differences in baseline characteristics between the groups. No differences were observed in procedural (HFLTV+RAP 74 [57-98] vs. HFLTV 66 [53-85.75] min, p=0.617) and RF (HFLTV+RAP 15.15 [11.22-21.22] vs. HFLTV 13.99 [11.04-17.13] min, p=0.620) times. Both groups showed a similar freedom from all-atrial arrhythmias at 12-month follow-up (HFLTV+RAP 82.68% vs. HFLTV 86.52%, HR=1.43, 95% CI [0.94-2.16], p=0.093). There were no significant differences in freedom from AF-related symptoms (HFLTV+RAP 91.4% vs. HFLTV 93.1%, p=0.476) or AF-related hospitalizations (HFLTV+RAP 98.5% vs. HFLTV 97.2%, p=0.320). Procedure-related complications were low in both groups (HFLTV+RAP 0.6% vs. HFLTV 0%, p=0.247). Conclusion: In patients undergoing RFCA for paroxysmal AF, adding RAP to HFLTV-ventilation was not associated with improved procedural and long-term clinical outcomes.

A 56-year-old man with non-ischemic cardiomyopathy with three prior ablations targeting two different MMVTs presented with recurrent VT. Therefore, he underwent epicardial mapping with adjuvant CT imaging which demonstrated midmyocardial scar. Fractionated potentials noted during mapping in this region, and entrainment suggested inner loop. Interestingly, pacing showed two different QRS morphologies identical to his previously ablated VTs with a long stim-QRS at this region. Epicardial ablation carried on during the VT successfully terminated it, but the VT remained inducible and required endocardial ablation to make it noninducible. The patient has been VT-free for 12 months following this ablation off antiarrhythmic drugs.

Background: Intracardiac echocardiography (ICE) is increasingly used during left atrial appendage occlusion (LAAO) as an alternative to transesophageal echocardiography (TEE) Aim: To evaluate the impact of ICE vs. TEE guidance during LAAO on procedural characteristics and acute outcomes, as well the presence of peri-device leaks and residual septal defects during follow-up. Methods: All studies comparing ICE-guided vs. TEE-guided LAAO were identified. The primary outcomes were procedural efficacy and occurrence of procedure-related complications. Secondary outcomes included lab efficiency (defined as a reduction in in-room time), procedural time, fluoroscopy time, and presence of peri-device leaks and residual interatrial septal defects (IASD) during follow-up. Results: Twelve studies (n=5637) were included. There were no differences in procedural success group (98.3% vs. 97.8%; OR 0.73, 95% CI 0.42-1.27, p=0.27; I2=0%) or adverse events (4.5% vs. 4.4%; OR 0.81 95% CI 0.56-1.16, p=0.25; I2=0%) between the ICE-guided and TEE-guided groups. ICE guidance reduced in in-room time (mean-weighted 28.6-minute reduction in in-room time) without differences in procedural time or fluoroscopy time. There were no differences in peri-device leak (OR 0.93, 95% CI 0.68-1.27, p=0.64); however, an increased prevalence of residual IASD was observed with ICE-guided vs. TEE-guided LAAO (46.3% vs. 34.2%; OR 2.23, 95% CI 1.05-4.75, p=0.04). Conclusion: ICE guidance is associated with similar procedural efficacy and safety, but could result in improved lab efficiency (as established by a significant reduction in in-room time). No differences in the rate of periprocedural leaks were found. A higher prevalence of residual interatrial septal defects was observed with ICE guidance.

Introduction: Capsulectomy is recommended in patients with cardiac implantable electronic device (CIED) infection after transvenous lead extraction (TLE) but is time-consuming and requires extensive tissue debridement. In this study, we describe the outcomes of chlorhexidine gluconate (CHG) scrubbing in lieu of capsulectomy for the treatment of CIED infections. Methods: This retrospective observational study included patients who underwent TLE for CIED-related infections. In the capsulectomy group, complete capsulectomy was performed after hardware removal. In the CHG group, thorough scrubbing of the generator pocket with 20 cc of 2% CHG followed by irrigation with approximately 500 cc of sterile normal saline (SNS) was performed. The primary outcomes included reinfection and hematoma formation in the generator pocket. Secondary outcomes included any adverse reaction to chlorhexidine, the need for reintervention, infection-related mortality, and total procedural time. Results: A total of 102 patients (mean age 67.2±13 years, 32.4% female) underwent CIED extraction with either total capsulectomy (n=54) or CHG (n=48) scrubbing. Hematoma formation was significantly higher in the capsulectomy group vs. the CHG group (13% vs. 0%, p=0.014), with no significant differences in the reinfection rate. Capsulectomy was associated with longer procedural time (133.7±78.5vs. 89.9±51.8 minutes, p=0.002). No adverse reactions to CHG were found. Four patients (4.3%) died from worsening sepsis: 3 in the capsulectomy group and 1 in the CHG group (p=0.346). Conclusions: In patients with CIED infections, the use of CHG without capsulectomy resulted in a lower risk of hematoma formation and shorter procedural times without an increased risk of reinfection or adverse events associated with CHG use.

Since the advent of catheter ablation (CA) for atrial fibrillation (AF) in 1998, our understanding of the pathophysiology, as well as our capacity to target triggers and effectively achieve freedom from AF, has come a long way. However, as the average age of the population and the prevalence of chronic diseases increases, the progression of AF from paroxysmal (PAF) into persistent (PersAF) and long-standing persistent AF (LSPAF) is on the rise. Given the complex mechanisms involved and the presence of multiple trigger sites leading to recurrences, managing non-PAF is a challenge for electrophysiologists around the globe. Multiple ablation techniques have been investigated, some of which have shown promising results, but a standardized technique is yet to be elucidated. In this review, we outline the evidence behind contemporary ablation techniques in the treatment of AF.

Introduction: Increasing evidence has suggested improved outcomes in atrial fibrillation (AF) patients with heart failure (HF) undergoing catheter ablation (CA) as compared to medical therapy. We sought to investigate the benefit of CA on outcomes of patients with AF and HF as compared to medical therapy. Methods and Results: A systematic review of PubMed, Embase, and Cochrane Central Register of Clinical Trials was performed for clinical studies evaluating the benefit of CA for patients with AF and HF. Primary endpoint was all-cause mortality. Secondary endpoints included atrial-arrhythmia recurrence and improvement in left ventricular ejection fraction (LVEF). Eight randomized controlled trials were included with a total of 2121 patients (mean age: 65 ± 5 years; 72% male). Mean follow-up duration was 32.9 ± 14.5 months. All-cause mortality in patients who underwent CA was significantly lower than in the medical treatment group (8.8% vs. 13.5%, RR 0.65, 95% CI 0.51-0.83, P=0.0005). A 35% relative risk reduction and 4.7% absolute risk reduction in all-cause mortality was observed with CA. Rates of atrial-arrhythmia recurrence were significantly lower in the CA group (39.9% vs 69.6%, RR 0.55, 95% CI 0.40-0.76, P=0.0003). Improvement in LVEF was significantly higher in patients undergoing CA (+9.4 ±7.6%) as compared to conventional treatment (+3.3±8%) (Mean difference 6.2, 95% CI 3.6-8.8, P<0.00001). Conclusion: CA for AF in patients with HF decreases all-cause mortality, improves atrial-arrhythmia recurrence rate and LVEF when compared to medical management. CA should be considered the treatment of choice to improve survival in this select group of patients.

Pulsed-Field Ablation: What Are the Unknowns and When Will They Cease to Concern Us?Nathaniel A. Steiger* and Jorge Romero, MD*