Kella, Danesh K

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.

ABSTRACT Background Transvenous lead extraction (TLE) is a commonly performed and generally safe procedure, though procedural complexity and risk can vary based on clinical and procedural factors. Objective This study aims to identify clinical and procedural factors associated with histologic evidence of subclinical vascular injury, defined by elastin positivity on extracted leads and its clinical significance. Methods Patients undergoing TLE with a lead dwell time of ≥ 1 year were included. Extracted leads with tissue were analyzed histologically using Verhoeff–Van Gieson staining to assess the presence of elastin. Demographic data, procedural and lead characteristics, and indication for extraction were obtained. Established extraction risk scores were calculated to determine efficacy in predicting subclinical vascular injury. Results The cohort included 49 patients with 92 leads extracted. A total of 25 patients (51%) had elastin‐positive leads. Complete procedural success occurred in 95.9% of cases. The multivariate regression model did not identify any independent predictors of elastin presence, including age (OR = 1.00; 95% CI 0.95–1.05; p = 0.89), female gender (OR = 3.04; 95% CI 0.67–13.65; p = 0.14), lead dwell time (OR = 1.13; 95% CI 0.98–1.29; p = 0.07). Additionally, no scoring system, such as the CCF, EROS, MB, SAFeTY, and LECOM, predicted the presence of elastin. Conclusion Subclinical venous injury was common following TLE, yet did not predict adverse clinical outcomes, reinforcing that TLE performed in experienced centers carries a favorable safety profile. Future studies in larger cohorts are needed to further characterize the clinical utility of subclinical vascular injury.

ABSTRACTIntroductionDurable left ventricular assist devices (LVADs) are susceptible to infection. The presence of a transvenous cardiac implantable electronic device (CIED) may further elevate this risk, making it necessary to remove the CIED system. This report presents the procedural characteristics and outcomes of CIED system extraction in patients with LVADs.MethodsThis is a single‐center retrospective study that included patients with durable LVADs who underwent transvenous CIED extraction at our institution from 2017 to 2023.ResultsTwenty patients with LVAD (HeartMate II = 14; HeartMate III = 6) underwent CIED removal during the study period. The median age was 52.5 (IQR = 42.5–56.5) years, and 7 patients had ischemic cardiomyopathy. Ninety percent (n = 18) of the extractions were due to infection, while 10% (n = 2) were for lead management. Complete removal of all leads was accomplished in 19 patients (95%). Overall, 40 out of 45 leads were removed during 20 procedures. Simple traction was used in 8 patients and specialized extraction tools were used in 12 (laser sheaths = 10; mechanical rotational sheaths = 7; both = 5). No leads were removed in one patient (5 leads; 2 abandoned leads with 42.5 years intravascular dwell time). There were no major procedure‐related complications. Two minor procedure‐related complications included a femoral arterial pseudoaneurysm and one pocket revision due to persistent surgical site bleeding. During a median follow‐up of 17 (IQR = 8.0–22.3) months, 8 patients underwent pump exchange due to persistent infection, and 15 remained on chronic suppressive antibiotics. Nine patients died during the follow‐up.ConclusionThe extraction of CIED systems in patients with LVAD is safe and feasible, exhibiting low procedure‐related morbidity and mortality. However, the long‐term prognosis for these patients remains poor despite the removal of CIEDs.

AbstractIntroductionPercutaneous left atrial appendage occlusion (LAAO) is traditionally performed under general anesthesia with trans‐esophageal echocardiography guidance. Intracardiac echo (ICE)‐guided LAAO closure is increasing in clinical use. The ICE catheter is crossed into LA via interatrial septum (IAS) after the septum is dilated with LAAO delivery sheath. This step can be time‐consuming and requires significant ICE catheter manipulation, which increases the risk of cardiac perforation. Pre‐emptive septal balloon dilation can potentially help with ICE advancement in the LA. We sought to evaluate the effect of pre‐dilation of the IAS with an 8 mm balloon on the ease of crossing the ICE catheter, fluoroscopy time for crossing, and overall procedure time.MethodsThe Piedmont LAAO registry was used to identify consecutive patients who underwent LAAO. The initial 25 patients in whom balloon dilation of the IAS was performed served as the experimental cohort, and the 25 consecutive patients before that in whom balloon dilation was not performed served as controls. In the experimental group, after a trans‐septal puncture, the sheath was retracted to the right atrium with a guidewire still in the LA. An 8 × 40 mm Evercoss™ over the wire balloon was inflated across the IAS. The ICE catheter was then crossed into the LA using the fluoroscopic landmark of the guide wire and the ICE imaging. The sheath was then advanced along the ICE catheter via the transseptal puncture (TSP) and the procedure continued. Follow‐up compputed tomography imaging was obtained at 4–8 weeks.ResultsEach group consisted of 25 patients. There were no significant differences in baseline characteristics. All procedures were performed successfully under conscious sedation and ICE guidance. There was a significant reduction in the overall procedure time, fluoroscopy time, and time for transseptal puncture to ICE in LA. There was no difference in the size of the acute residual interatrial shunt, as measured via ICE, or the size and presence of iatrogenic ASD at follow‐up.ConclusionBalloon dilation of TSP is safe and is associated with increased efficiency in ICE‐guided LAAO procedures.

Background: Percutaneous left atrial appendage occlusion (LAAO) is traditionally performed under general anesthesia with trans-esophageal echocardiography guidance. Intracardiac echo (ICE) guided LAAO closure is increasing in clinical use. The ICE catheter is crossed into LA via interatrial septum (IAS) after the septum is dilated with LAAO delivery sheath. This step can be time-consuming and requires significant ICE catheter manipulation increasing the risk of cardiac perforation. Pre-emptive septal balloon dilation can potentially help with the advancement of ICE in LA. Objective: Evaluate the effect of pre-dilation of IAS with an 8 mm balloon on ease of crossing the ICE catheter, fluoroscopy time for crossing, and overall procedure time. Methods: The Piedmont LAAO registry was used to identify consecutive patients undergoing LAAO. The initial 25 patients where balloon dilation of IAS was performed served as the experimental cohort, and the 25 consecutive patients prior to that in whom balloon dilation was not performed, served as controls. For the experimental group, after a trans-septal puncture, the sheath was retracted to the right atrium with guide wire still in the LA. An 8x40 mm Evercoss™ over the wire balloon was inflated across the IAS. The ICE catheter was then crossed into the LA using the fluoroscopic landmark of the guide wire and the ICE imaging. The sheath was then advanced along the ICE catheter via the transseptal puncture (TSP) and the procedure continued. Follow up CT imaging was obtained in 4-8 weeks. Results: Each group included 25 patients. There were no significant differences in baseline characteristics. All procedures were performed successfully with the use of conscious sedation and ICE guidance. There was a significant reduction in overall procedure time, fluoroscopy time, and time for trans-septal puncture to ICE in LA. There was no difference in the size of the acute residual interatrial shunt as measured via ICE or size and presence of iatrogenic ASD at follow up. Conclusion: Balloon dilation of TSP is safe and associated with increased efficiencies in ICE guided LAAO procedures.

Introduction: The subcutaneous-ICD (S-ICD) and its electrode were developed to avoid long-term complications of transvenous leads in the vasculature. Methods: We report a case of unexpected, inappropriate S-ICD shocks due to oversensing of high amplitude, non-physiologic, electrical noise artifacts that were not preceded by high impedance alerts or sensing electrogram noise detections. Results: Following explant, high-magnification, X-ray imaging of the S-ICD electrode demonstrated partial fracture of the distal sensing conductor located near a short radius bend in the electrode at the electrode-header interface. Conclusions: Clinicians should be aware of a potential for fatigue failure fracture of the S-ICD electrode. Recommendations for systematic S-ICD follow-up and troubleshooting are discussed.

AbstractBackgroundMagnetic resonance imaging (MRI) in patients with legacy cardiovascular implantable electronic devices (CIEDs) in situ is likely underutilized. We hypothesized the clinical benefit of MRI would outweigh the risks in legacy CIED patients.MethodsThis is a single‐center retrospective study that evaluated and classified the utility of MRI using a prospectively maintained database. The outcomes were classified as aiding in diagnosis, treatment, or both for the patients attributable to the MRI. We then assessed the incidence of adverse effects (AE) when the MRI was performed.ResultsIn 668, MRIs performed on 479 patients, only 13 (1.9%) MRIs did not aid in the diagnosis or treatment of the patient. Power‐on reset events without clinical sequelae in three scans (0.45%) were the only AE. The probability of an adverse event happening without any benefit from the MRI scan was 1.1 × 10−4. A maximum benefit in diagnosis using MRI was obtained in ruling out space‐occupying lesions (121/185 scans, 65.4%). Scans performed in patients for elucidating answers to queries in treatment were most frequently done for disease staging at long term follow‐up (167/470 scans, 35.5%). Conservative treatment (184/470 scans, 39%) followed by medication changes (153/470 scans, 28.7%) were the most common treatment decisions made.ConclusionsThe utility of MRI in patients with non‐MRI‐conditional CIEDs far outweighs the risk of adverse events when imaging is done in the context of a multidisciplinary program that oversees patient safety.

AbstractIntroductionVenous stenosis is a well‐recognized complication of transvenous leads (TVLs) that is encountered during lead revisions or device upgrades. We here report the outcomes of TVL placement facilitated by fibroplasty or tunneling (TUN) procedure.MethodsWe conducted a single‐center retrospective cohort study of all patients undergoing TVL implantation requiring fibroplasty or TUN from 2005 to 2017. Medical records and procedure reports were reviewed for relevant data. Outcomes for fibroplasty and TUN to facilitate TVL placement were compared.ResultsSixty patients had fibroplasty and thirty‐five patients had a TUN procedure. There was no difference in procedure success rates between the two groups (97% fibroplasty vs. 100% TUN; p = .98). The fluoroscopy time was longer (fibroplasty = 39.7 ± 21.5 min vs. TUN = 29.2 ± 21.3 min; p = .01) and the total procedural time was shorter in the fibroplasty group (fibroplasty = 247 ± 77.8 min vs. TUN = 287 ± 77.1 min; p = .01). TUN was associated with a significantly higher incidence of acute complications (fibroplasty = 0 vs. TUN = 8; p = .002) most requiring invasive intervention and/or transfusion with blood products. Long‐term complications requiring additional device‐related procedures were comparable between the two groups (fibroplasty = 6 vs. TUN = 6; logrank p = .21).ConclusionsFor patients with venous stenosis requiring additional TVL, balloon fibroplasty is associated with similar rates of success and a significantly decreased incidence of acute complications when compared with subcutaneous TUN.

AbstractIntroductionMyocardial infarction (MI) is associated with an increase in subsequent heart failure (HF), recurrent ischemic events, sudden cardiac arrest, and ventricular arrhythmias (SCA‐VA). The primary objective of the study to determine the role of intercurrent HF and ischemic events on the development of SCA‐VA following first type I MI.Methods and resultsA retrospective cohort study of patients experiencing first type 1 MI in Olmsted County, Minnesota (2002‐2012) was conducted by identifying patients using the medical records linkage system (Rochester epidemiology project). Patients aged ≥18 years were followed from the time of MI till death or 31 July, 2017. Intercurrent HF and ischemic events were the primary exposures following MI and their association with outcome SCA‐VA was assessed. Eight hundred and sixty‐seven patients (mean age was 63 ± 14.5 years; 69% male; 49.8% ST‐elevation myocardial infarction) who had their first type I MI during the study period were included. Majority of acute MI patients were revascularized using percutaneous coronary intervention and bypass surgery (628 [72.43%] and 87 [10.03%] respectively). During a mean follow‐up of 7.69 ± 4.17 years, HF, recurrent ischemic events and SCA‐VA occurred in 155 (17.9%), 245 (28.3%), and 40 (4.61%) patients respectively. Low ejection fraction (adjusted hazard ratio [HR] 0.95; 95% confidence interval [CI], 0.93‐0.98; P < .001), intercurrent HF (adjusted HR 3.11; 95% CI, 1.39‐6.95; P = .006) and recurrent ischemic events (adjusted HR 3.47; 95% CI, 1.68‐7.18; P < .001) were associated with subsequent SCA‐VA.ConclusionSCA‐VA occurred in a small proportion of patients after MI and is associated with intercurrent HF and recurrent ischemic events.