Pulsed Field Research Articles

Analysis of long-lasting tumor-specific antibodies from murine tumors treated with Aliya pulsed electric fields.

e14543 Background: Pulsed electric field (PEF) tissue destruction has demonstrated meaningful systemic immune responses in mice that are superior to thermal ablation, and synergize effectively with systemic chemotherapy and checkpoint blockade (CPB) immunotherapy. Immune cell populations are increased by PEF, including tumor specific activated CD8 T-cells and plasma B-cells. Antitumor immunity can include the presence of circulating anti-cancer antibodies. However, the presence and role of circulating tumor specific antibodies induced by PEF have not been explored. Serological antibodies are often detected with the ELISA assay, where tumor-associated antigens are coated to a microtiter plate to attract the corresponding serum antibodies. Here, we quantify IgG tumor specific antibodies after PEF using an in-house ELISA. Methods: Mice bearing immune-warm (EMT6) and immune-cold (4T1) orthotopic murine breast tumors were treated with a biphasic PEF dose comparable to Aliya titrated for mouse tumors. To detect tumor specific circulating IgG1 immunoglobulin in serum, an ELISA plate was coated with EMT6 and 4T1 protein lysate, as well as with a known 4T1-expressed tumor-specific antigen (gp70). Serum draws from the treated, untreated, and naïve mice were exposed to the coated wells for 1 hour. Bound IgG were detected by anti-mouse IgG (HRP tagged) antibody added to the wells and incubated 1 hour. A TMB substrate was added and color development was allowed for 15 minutes. The optical density was quantified using a microtiter plate reader. Results: ELISA quantification of serum IgG at multiple timepoints show that 4T1 tumor-specific IgG antibodies were increased 14.3- and 2.6-fold by day 20 in the PEF-treated and untreated group survivors relative to Naïve mice, respectively, (OD=0.86 and 0.15 v. 0.06). Furthermore, IgG antibodies specific to the gp70 antigen of the 4T1 cell line were increased by 44.9- and 2.7-fold in the PEF-treated and untreated groups relative to naïve mice (OD=3.14 and 0.19 v. 0.07). In the EMT6 model, at 3 months post-treatment, only the PEF-ablated group mice survived, and showed 15.5-fold higher antibodies against EMT6 tumor antigens compared to naive mice (OD=0.62 v. 0.04). Conclusions: The specific form of PEF in this study generated tumor-specific IgG long-lived antibodies in mice for immune-warm and immune-cold tumor models, corroborating previous findings of increased murine B-cell and plasma cell populations. This effect has not been well-reported for other ablation technologies. Increases were evident by Day 20 post-PEF and persisted at least 3 months. These murine data suggest the PEF used may invoke potent, long-lived immune responses and anti-tumor immune surveillance, offering a potential approach for in situ tumor vaccination to improve metastatic disease outcomes. Future studies should determine response durability and its role in attaining distant tumor clearance.

An integrative review of pulsed electromagnetic field therapy (PEMF) and wound healing

An integrative review of pulsed electromagnetic field therapy (PEMF) and wound healing

Використання комплексу газогрунтової зйомки та геофізичних досліджень у задачі окреслення території грязьового вулканізму в межах Розвадівської площі Львівської області

The purpose of the research was to substantiate the scientific basis behind the formation of a mud volcano within a specific section of the Precarpathian depression. It also aims to examine the existence of a near-fault shallow gas deposit in the Rozvadiv area and its possible impact on gas-soil surveying and electrometry fields. The relevance of the work is determined by the need to solve the ecological problem of environmental pollution with hydrocarbon gases, as well as to establish and forecast the degree of emissions of the gas-mud mixture. At the same time, the problem of the presence (or absence) of the relationship between the influence of the Rudnyk gas-prospecting area, which is impacted by drilling, and the Rozvadiv deposit mentioned above is solved by comparing the results of gas-soil and geophysical surveys on a significant territory covering the specified areas. The research methodology consists of the following: 1) application of research with different physical justifications (gas-soil survey and electrometry); 2) comparison of the survey results from the same area and the same grid of observations; 3) detection of anomalies within the studied territory and their interpretation from the point of view of the development of mud volcanism. Research results. The information basis of gasometry involves direct measurements of free gas in a observation regular system in the soil environment atmosphere, their statistical characteristics, and calculated indicators of gas contamination. Therefore, the gas distribution maps are informative. The applied research using the method of Earth’s natural pulsed electromagnetic field made it possible to differentiate the area according to the intensity degree of electromagnetic radiation, taking into account the different depths of the sources, and, thus, identify areas of stressed-strain state of rocks and qualify them by the causes. The scientific novelty lies in the following: 1) indicating the absence of connections between the massif impacted by drilling and a natural disaster; 2) specifying the causes of the natural disaster and its substantiated mechanism and classifying the event as a mud volcano. Practical significance. Interpretation of the obtained results makes it possible to determine the causes of the extraordinary geological event in the Rozvadiv area of the Lviv region, classify the event and its consequences as a manifestation of elements of mud volcanism, and establish the absence of a relationship between the specified event and man-made impact (drilling) of the geological environment in the neighbouring areas.

Comparative Efficacy and Safety of Pulsed Field Ablation Versus Radiofrequency Ablation of Idiopathic LV Arrhythmias

BackgroundComparative efficacy and safety data on radiofrequency ablation (RFA) versus pulsed field ablation (PFA) for common idiopathic left ventricular arrhythmia (LV-VAs) locations are lacking. ObjectivesThis study sough to compare RFA with PFA of common idiopathic LV-VAs locations. MethodsTen swine were randomized to PFA or RFA of LV interventricular septum, papillary muscle, LV summit via distal coronary sinus, and LV epicardium via subxiphoid approach. Ablations were delivered using an investigational dual-energy (RFA/PFA) contact force (CF) and local impedance-sensing catheter. After 1-week survival, animals were euthanized for lesion assessment. ResultsA total of 55 PFA (4 applications/site of 2.0 KV, target CF ≥10 g) and 36 RFA (CF ≥10 g, 25–50 W targeting ≥50 Ω local impedance drop, 60-second duration) were performed. LV interventricular septum: average PFA depth 7.8 mm vs RFA 7.9 mm (P = 0.78) and no adverse events. Papillary muscle: average PFA depth 8.1 mm vs RFA 4.5 mm (P < 0.01). Left ventricular summit: average PFA depth 5.6 mm vs RFA 2.7 mm (P < 0.01). Steam-pop and/or ventricular fibrillation in 4 of 12 RFA vs 0 of 12 PFA (P < 0.01), no ST-segment changes observed. Epicardium: average PFA depth 6.4 mm vs RFA 3.3 mm (P < 0.01). Transient ST-segment elevations/depressions occurred in 4 of 5 swine in the PFA arm vs 0 of 5 in the RFA arm (P < 0.01). Angiography acutely and at 7 days showed normal coronaries in all cases. ConclusionsIn this swine study, compared with RFA, PFA of common idiopathic LV-VAs locations produced deeper lesions with fewer steam pops. However, PFA was associated with higher rates of transient ST-segment elevations and depressions with direct epicardium ablation.

Prevalence, timing, and impact of early recurrence of atrial tachyarrhythmias after pulsed field ablation: A secondary analysis of the PULSED AF trial

BackgroundEarly recurrence of atrial tachyarrhythmias (ERAT) within 3 months of thermal ablation for atrial fibrillation (AF) is common and often considered transient. Pulsed field ablation (PFA) is a nonthermal energy source in which ERAT is not well described. ObjectiveThe purpose of this study was to analyze ERAT in patients with AF undergoing PFA in the Pulsed Field Ablation to Irreversibly Electroporate Tissue and Treat AF (PULSED AF) trial. MethodsThis analysis included 154 (52.4%) paroxysmal AF and 140 (47.6%) persistent AF who had ≥10 rhythm assessments during the 90-day blanking period. ERAT was defined as any instance of ≥30 seconds of AF, atrial flutter, or atrial tachycardia on transtelephonic monitoring (weekly and symptomatic) or ≥10 seconds on electrocardiography (at 3 months), both within 90 days. Late recurrence of atrial tachyarrhythmias (LRAT) was defined as observed atrial tachyarrhythmias between 90 days and 12 months. ResultsThe overall prevalence of ERAT was 27.1% in patients with paroxysmal AF and 31.6% in patients with persistent AF. In patients with ERAT, 73% had ERAT onset within the first month of the procedure. The presence of ERAT was associated with LRAT in patients with paroxysmal AF (hazard ratio 6.4; 95% confidence interval 3.6–11.3) and patients with persistent AF (hazard ratio 3.8; 95% confidence interval 2.2–6.6). Yet, in 29.4% of patients with paroxysmal AF and 34.3% of patients with persistent AF with ERAT, LRAT was not observed. LRAT was positively correlated with the number of ERAT observations. ConclusionERAT after PFA predicted LRAT in patients with paroxysmal and persistent AF. However, the concept of a blanking period after PFA is still valid, as approximately one-third of patients with ERAT did not continue to have LRAT during follow-up and may not need reablation.

Pulsed electric field induces exocytosis and overexpression of MAGE antigens in melanoma

Nanosecond pulsed electric field (nsPEF) has emerged as a promising approach for inducing cell death in melanoma, either as a standalone treatment or in combination with chemotherapeutics. However, to date, there has been a shortage of studies exploring the impact of nsPEF on the expression of cancer-specific molecules. In this investigation, we sought to assess the effects of nsPEF on melanoma-specific MAGE (Melanoma Antigen Gene Protein Family) expression. To achieve this, melanoma cells were exposed to nsPEF with parameters set at 8 kV/cm, 200 ns duration, 100 pulses, and a frequency of 10 kHz. We also aimed to comprehensively describe the consequences of this electric field on melanoma cells' invasion and proliferation potential. Our findings reveal that following exposure to nsPEF, melanoma cells release microvesicles containing MAGE antigens, leading to a simultaneous increase in the expression and mRNA content of membrane-associated antigens such as MAGE-A1. Notably, we observed an unexpected increase in the expression of PD-1 as well. While we did not observe significant differences in the cells' proliferation or invasion potential, a remarkable alteration in the cells' metabolomic and lipidomic profiles towards a less aggressive phenotype was evident. Furthermore, we validated these results using ex vivo tissue cultures and 3D melanoma culture models. Our study demonstrates that nsPEF can elevate the expression of membrane-associated proteins, including melanoma-specific antigens. The mechanism underlying the overexpression of MAGE antigens involves the initial release of microvesicles containing MAGE antigens, followed by a gradual increase in mRNA levels, ultimately resulting in elevated expression of MAGE antigens post-experiment. These findings shed light on a novel method for modulating cancer cells to overexpress cancer-specific molecules, thereby potentially enhancing their sensitivity to targeted anticancer therapy.

Pulsed Electromagnetic Field Enhances Caffeic Acid Phenethyl Ester-induced Death of MCF-7 Breast Cancer Cells.

Caffeic acid phenethyl ester (CAPE) exerts anticancer effects against several cancer types, including breast cancer. Pulsed electromagnetic field (PEMF) improves the efficiency of some chemotherapeutic drugs. In this study, we examined the effects of PEMF stimulation on the anticancer activity of CAPE in MCF-7 breast cancer cells and the underlying signal transduction pathways. MCF-7 cells were seeded and incubated for 24 h. Each of the drugs (5-fluorouracil, paclitaxel, gefitinib, or CAPE) was added to the cells on day 0. Then, cells were immediately stimulated with a 60-min PEMF session thrice a day (with 4-h interval between sessions) for 1-3 days. Cell death and viability were assessed by flow cytometry and trypan blue dye exclusion assay. Molecular mechanisms involved in cell death were confirmed by western blot assay. Compared with treatment with CAPE alone, co-treatment with CAPE and PEMF more strongly reduced the viability of MCF-7 cells, further increased the percentage of the sub-G1 population, poly (ADP-ribose) polymerase (PARP) cleavage, activation of apoptotic caspases, up-regulation of pro-apoptotic proteins, such as Fas cell surface death receptor (FAS) and BCL2 associated X, apoptosis regulator (BAX), and reduced the expression of anti-apoptotic proteins, such as BCL-2 apoptosis regulator (BCL-2), MCL-1 apoptosis regulator, BCL-2 family member (MCL-1), and survivin. PEMF stimulation also increased CAPE-induced phosphorylation of p53, and inhibition of p53 partially restored the PEMF-reduced viability of CAPE-treated MCF-7 cells. PEMF stimulation enhanced CAPE-induced cell death by activating p53, which regulates the expression of apoptosis-related molecules, subsequently activating the caspase-dependent apoptotic pathway in MCF-7 cells, suggesting that PEMF can be utilized as an adjuvant to enhance the effect of CAPE on breast cancer cells.

The potential of pulsed electromagnetic field-generated shock waves for reducing microbial load and improving homogenization in raw milk

Milk is a highly nutritious food essential for human consumption. However, traditional thermal processing methods can reduce its nutritional value and cause unwanted changes. The use of shock waves produced by pulsed electromagnetic fields (PEMFs) has been explored as a means to reduce pathogenic microorganisms. The effect of shock wave treatment on microbial load and particle distribution in packaged fresh cow's milk was investigated. Additionally, the impact of shock wave treatment on Salmonella enterica counts in a bacterial suspension of phosphate-buffered saline (PBS) was evaluated, as this bacterium is a significant milkborne pathogen. Treatment with 1000 impulses from an electromagnetic shock wave generator resulted in a 0.7-log reduction in the total bacterial count of milk. In a separate experiment, a 300-impulse shock wave treatment applied to a Salmonella enterica suspension achieved a 3-log reduction in bacterial counts. Furthermore, shock wave treatment resulted in a decrease in milk particle size compared to untreated milk. Notably, the volume of milk used in this study aligns with commercially available packaged products, enhancing the experiment's industrial relevance. The use of PEMF to generate shock waves could provide a novel approach for future studies focused on reducing the microbial load of milk and improving its homogenization.

National workflow experience with pulsed field ablation for atrial fibrillation: learning curve, efficiency, and safety.

Recent data on pulsed field ablation (PFA) for atrial fibrillation (AF) ablation suggest a progressive reduction in procedural times. Real-world data regarding the relationship between the learning curve of PFA and clinical outcomes are scarce. The objective was to evaluate the PFA learning curve and its impact on acute outcomes. Consecutive patients undergoing AF ablation with the FARAPULSE™ PFA system were included in a prospective, non-randomized multicenter study. Procedural times were stratified on the operators' learning curve. Comparative analysis of skin-to-skin time was conducted with radiofrequency (RF) and cryoablation (CB) pulmonary vein isolation (PVI) procedures performed by the same operators in the previous year. Among 752 patients, 35.1% were females, and 66.9% had paroxysmal AF; mean age was 62.2 ± 10 years. A total of 62.5% of procedures were performed by operators with > 20 PFA procedures. Both time to PVI (25.6 ± 10 min vs 16.5 ± 8, p < 0.0001) and fluoroscopy time (19.8 ± 8 min vs 15.9 ± 8 min, p = 0.0045) significantly improved after 10 associated with consistent linear trend towards procedural time reduction (R2 0.92-0.68 across various procedural metrics). Current PFA skin-to-skin time was lower than the historical skin-to-skin one in 217 (62.4%) procedures; it was similar in 112 (32.2%) cases and higher than the historical skin-to-skin one in 19 (5.5%). No major complications were reported. In this nationwide multicentric experience, the novel PFA system proved to be fast, safe, and acutely effective in both paroxysmal and persistent AF patients. The learning curve appears to be rapid, as improvements in procedural parameters were observed after only a few procedures. Advanced TecHnologies For SuccEssful AblatioN of AF in Clinical Practice (ATHENA). URL: http://clinicaltrials.gov/ Identifier: NCT05617456.

Pulsed electric field effect on acrylamide reduction and quality attributes of continuous-style Lamoka potato chips

Potato chips are a popular snack, well-liked because of their texture-flavor combination. Potato chips are made by frying slices of potato in vegetable oil to achieve a crispy texture. Frying potato slices initiates the Maillard reaction, resulting in chemical changes that enhance taste, color, and texture, but also undesired acrylamides, which are suspected carcinogens. The application of pulsed electric field (PEF) technology is commonly used in French fry processing operations to prolong cutting blade sharpness and reduce waste, energy consumption, and water usage. Despite these attributes, PEF systems have not yet gained widespread adoption by potato chip producers. In the current study, Lamoka potatoes were PEF-treated prior to continuous frying into potato chips. The effect of specific energy at 0.75 kJ/kg (Low-PEF) and 1.5 kJ/kg (High-PEF) and electric field strength of 1 kV/cm, frequency of 24 kV, and pulse width of 6 μs versus untreated (control) samples was studied, then batches of 250 g of slices were fried at 170 °C or 185 °C for two frying times to obtain potato chips with acrylamide levels below the California Proposition 65 limit (275 ng/g). The Lamoka potato chip product quality metrics that were assessed include moisture, fat, reducing sugars, asparagine, acrylamide, chip color, and texture. PEF treatment of Lamoka potatoes resulted in chips fried in 10 % less time, lower oil content by 8 %, and a decrease of reducing sugars by 19.2 %, asparagine by 42.0 %, and acrylamide by 28.9 %. The PEF fried chips were lighter in color but maintained textural attributes compared to continuous frying cooking. The process of frying potato slices at 170 °C for 150 s with High-PEF yielded potato chips with acrylamide content below the California Proposition 65 limit; which speaks to the health implications for consumers and the quality and safety of these chips.

Considering Joule heating in coupled electroporation and electrodeformation modeling of glioblastoma cells

Cells exposed to a pulsed electric field undergo electroporation(EP) and electrodeformation(ED) under electric field stress, and a coupled model of EP and ED of glioblastoma(GBM) taking into account Joule heating is proposed. The model geometry is extracted from real cell boundaries, and the effects of Joule heating-induced temperature rise on the EP and ED processes are considered. The results show that the temperature rise will increase the cell's local conductivity, leading to a decrease in the transmembrane potential(TMP). The temperature rise also causes a decrease in the dynamic Young's modulus of the cell membrane, making the cell less resistant to deformation. In addition, GBM cells are more susceptible to EP in the middle portion of the cell and ED in the three tentacle portions under pulsed electric fields, and the cells undergo significant positional shifts. The ED of the nucleus is similar to spherical cells, but the degree of ED is smaller.

Pulsed electromagnetic fields used in regenerative medicine: An in vitro study of the skin wound healing proliferative phase.

Numerous studies have demonstrated the efficacy of extremely low frequency-pulsed electromagnetic fields (ELF-PEMF) in accelerating the wound healing process in vitro and in vivo. Our study focuses specifically on ELF-PEMF applied with the Magnomega® device and aims to assess their effect during the main stages of the proliferative phase of dermal wound closure, in vitro. Thus, after the characterization of the EMFs delivered by the Magnomega® unit, primary culture of human dermal fibroblasts (HDFs) were exposed, or not for the control culture, to 10-12and 100 Hz ELF-PEMF. These parameters are used in clinical practice by physiotherapists in order to enhance healing of dermal lesions in patients. HDFs proliferation was first assessed and revealed an increase in the expression of one of the two genetic markers of cell proliferation tested (PCNA and MKI67), after initial exposure of the cells to 10-12 Hz PEMF. Next, migration of HDFs was investigated by performing scratch assays on HDF layers. The observed wound closure kinetics corroborate the early organization of actin stress fibers that was revealed in the cytoplasm of HDFs exposed to 100 Hz ELF-PEMF. Also, maturation of HDFs into myofibroblasts was significantly increased in cells exposed to 10-12or to 100 Hz PEMF. The present study is the first to demonstrate, in vitro, an early stimulation of HDFs, after their exposure to ELF-PEMF delivered by the Magnomega® device, which could contribute to an acceleration of the wound healing process.

Transient square pulse-electric field induction of monosex-male reversal of the eggs of Nile tilapia (Oreochromis niloticus L., Chitralada)

We present an alternative technique of monosex-male reversal for Nile tilapia using transient square pulse-electric field inductions to enhance sex reversal rate of tilapia eggs by methyltestosterone (Oreochromis niloticus L., Chitralada). Male tilapia is preferred for aquaculture because of better size and growth rate. The egg membrane was permeabilised by an electric field pulse allowing a minimalized androgen hormone dose of 17alpha-methyltestosterone (MT) (μg l−1 concentration) to achieve monosex sex-male reversal. The technique achieved large-scale inductions of 2000 eggs rather than for individual eggs and was aimed at commercialization (Thailand petty patent no. 13516). The eggs of O. niloticus obtained from our parent breeding stocks were carefully selected to be in the segmentation-pharyngula stage (2–3 dpf - day post fertilization) for electrical inductions in a pulsed-electric field generated between narrow parallel-plate electrodes. The electrodes were powered with an adjustable signal pulse-generator (SPG) developed for on-site operations. The induction medium was prepared using HEPES buffer mixed with a minimized concentration of MT. We experimentally optimized inductions by adjusting the number of square wave pulses, pulse amplitude, pulse durations (period) and a mark-space ratio (pulse width: negative half of period) for the optimum results. A dose of 350 V (electric field intensities of 87.50 kV m−1) of 3 square pulses with 100 μs pulse-period (50:50 mark space ratio) gave the maximum rate of male-sex reversal rate (MSR) of 89.42 ± 2.28 (SD)%, hatching rate (HR) of 93.33 ± 0.58% and survival rate (SR) of 87.49 ± 1.71%, respectively. The off-spring rate (OSR) or sex ratio of the controls were 59.71 ± 3.00% male and 46.33 ± 1.53% female from a hatching rate (HR) of 91.33 ± 1.53% and a survival rate (SR) of 85.08 ± 4.16%, respectively.

Characterization of the electropermeabilization induced by pulsed electric field (PEF) technology and its effect on the ultrasonic-assisted drying of yellow turnip

Obtaining snacks from the drying of surplus vegetables is an alternative to reduce waste. A combination of pulsed electric field (PEF) pretreatments and ultrasonic-assisted (US) drying could significantly enhance the process, as this is the aim of this study. PEF pretreatments of yellow turnip significantly affected the cell disintegration index (CDI) and the water holding capacity (WHC): the more intense the PEF treatment, the greater the CDI and the lower the WHC. Both parameters, CDI and WHC, showed a high degree of correlation which indicated that WHC can be an alternative index to CDI to assess PEF effects on food matrices. Regarding yellow turnip drying (40 °C), PEF pretreatments (CDI 0.25 and 0.75) and US application (20.5 kW/m3) significantly accelerated the operation, but it was the combination of both technologies that provided the shortest process (CDI 0.75). PEF could generate changes in the food matrix which enhance the US effects on mass transfer.

Pulsed field vs very high-power short-duration radiofrequency ablation for atrial fibrillation: Results of a multicenter, real-world experience

BackgroundPulsed field ablation (PFA) and very high-power short-duration (vHPSD) radiofrequency ablation are the most recently introduced technologies for atrial fibrillation (AF) ablation. The procedural performance, safety, and effectiveness of PFA vs vHPSD are currently unknown. ObjectiveThe study aimed to compare PFA with vHPSD for the treatment of paroxysmal or persistent AF. MethodsWe conducted an observational, multicenter study enrolling 534 consecutive patients (63 ± 9 years; 36% female) with paroxysmal (n = 368 [69%]) or persistent (n = 166 [31%]) AF undergoing ablation by either PFA (Farapulse; n = 192) or vHPSD (90 W/4 seconds; QDOT Micro; n = 342) between 2020 and 2023. Atrial tachyarrhythmia recurrence after a 1-month blanking period was the primary efficacy end point and was assessed both overall and in propensity score–matched patients. The primary safety end point was a composite of procedure-related complications. ResultsSuccessful pulmonary vein isolation was achieved in all patients, with shorter procedure duration (PFA,70 minutes; vHPSD, 100 minutes; P < .001) but longer fluoroscopy time (PFA, 15 minutes; vHPSD, 7 minutes; P < .001) in the PFA group. PFA was associated with more frequent use of general anesthesia (P < .001). Primary safety outcome events occurred in 19 patients (3.5%), with similar prevalence in both groups (PFA, 4%; vHPSD, 3%; P = .745). After a median follow-up of 12 (9–12) months, survival free from recurrent atrial tachyarrhythmia was similar between the PFA and vHPSD groups, both overall (12-month estimate: PFA, 75%; vHPSD, 76%; log-rank P = .73) and in propensity score–matched patients (n = 342; 12-month estimate: PFA, 75%; vHPSD, 77%; log-rank P = .980). ConclusionIn a large, multicenter experience, PFA was associated with more common use of general anesthesia, shorter procedural times, and longer fluoroscopy exposure compared with vHPSD ablation, with both techniques displaying superimposable safety and efficacy.

Safety and effectiveness of additional left atrial posterior wall ablation using pulsed field ablation for persistent and long-standing persistent atrial fibrillation patients.

The unique safety profile of pulsed field ablation (PFA) has made pulmonary vein isolation (PVI) + left atrial posterior wall (LAPW) ablation promising for treating persistent atrial fibrillation (PerAF). The goal of this study was to assess long-term freedom from atrial fibrillation, atrial flutter, and atrial tachycardia (AF/AFL/AT), as well as the safety and feasibility of LAPW PFA using multipolar, pentaspline Farawave catheter. Retrospective observational study at a single institution. Data for 94 patients were collected from a prespecified intraprocedural registry. The long-term AF/AFL/AT recurrence assessment was based on an analysis of medical history; 24-h Holter ECGs at 3, 6, and 12 months postablation; and 12-lead ECGs recorded during symptomatic episodes or visits. Half of the patients had ls-PerAF, and half had a history of catheter ablation-mostly RF PVI. The acute ablation success rate was 100%, and the primary safety outcome was observed in 2 patients. Fifty patients experienced AF/AFL/AT recurrence (54.3%). An increase in LAPW low-voltage areas and AF classification were associated with arrhythmia recurrence. After a median follow-up of 13 months, the Kaplan‒Meier estimated median time free of AF/AFL/AT after a single procedure was 14.7 months. PFA PVI + PWA had the best outcome in perAF patients without extensive LA fibrosis. AF recurrence was paroxysmal in significant part of the cohort. The addition of PWA to PVI using multipolar PFA was safe and did not significantly influence the transpired ablation time.

Efficacy and safety of pulsed field ablation for accessory pathways: a pilot study.

Radiofrequency ablation is used as a first-line therapy for accessory pathways (APs). However, data regarding the effects of pulsed field ablation (PFA) on APs are limited. We sought to evaluate the acute procedural and 6-month success and safety of PFA in a cohort of patients with APs. A focal contact force-sensing PFA catheter was used for patients with APs. Pulsed field ablation generator generated a bipolar and biphasic waveform (±1000 V) with a duration of 100 ms from the tip of the PFA catheter. A 100% acute procedural success was achieved in 10 conscious patients with APs (7 left anterolateral, 2 left inferolateral, and 1 right posteroseptal APs) including 6 (60%) patients after an initial application. The average total ablation time was 6.3 ± 4.9 s for 4.7 ± 1.8 ablation sites (ASs), including 3.1 ± 2.4 s at targets and 3.2 ± 2.9 s at 3.2 ± 2 bolus ASs. The mean skin-to-skin time was 59.3 ± 15.5 min, and PFA catheter dwell time was 29.4 ± 7.8 min. One patient encountered transient sinus arrest during PFA due to parasympathetic overexcitation. Sinus rhythm was restored in all patients without any significant adverse events during the short-term follow-up. Pulsed field ablation of APs was feasible, effective, and safe. Its efficiency was remarkable for its ultrarapid termination of AP conduction. Further studies are warranted to prove whether utilization of PFA with current parameters can extend to manifold AP ablation.

The impact of magnesium content on lithium-magnesium alloy electrode performance with argyrodite solid electrolyte

Solid-state lithium-based batteries offer higher energy density than their Li-ion counterparts. Yet they are limited in terms of negative electrode discharge performance and require high stack pressure during operation. To circumvent these issues, we propose the use of lithium-rich magnesium alloys as suitable negative electrodes in combination with Li6PS5Cl solid-state electrolyte. We synthesise and characterise lithium-rich magnesium alloys, quantifying the changes in mechanical properties, transport, and surface chemistry that impact electrochemical performance. Increases in hardness, stiffness, adhesion, and resistance to creep are quantified by nanoindentation as a function of magnesium content. A decrease in diffusivity is quantified with 6Li pulsed field gradient nuclear magnetic resonance, and only a small increase in interfacial impedance due to the presence of magnesium is identified by electrochemical impedance spectroscopy which is correlated with x-ray photoelectron spectroscopy. The addition of magnesium aids contact retention on discharge, but this must be balanced against a decrease in lithium diffusivity. We demonstrate via electrochemical testing of symmetric cells at 2.5 MPa and 30∘C that 1% magnesium content in the alloy increases the stripping capacity compared to both pure lithium and higher magnesium content alloys by balancing these effects.

Pulmonary Vein Isolation with Pulsed Field Ablation and Size-Adjustable Cryo-Balloon: A Comparative Procedural Analysis of First-Time Use.

Background: Pulmonary vein isolation (PVI) is the standard of care for the treatment of symptomatic atrial fibrillation (AF). Novel techniques for PVI are the thermal size-adjustable cryo-balloon (CB) system and non-thermal pulsed field ablation (PFA) system. There are currently no data available for a direct comparison between these two systems. Furthermore, with new techniques, it is important to ensure a high level of efficiency and safety during treatment right from initial use. Therefore, the aim of this study was to directly compare the procedural data and safety of these two new PVI techniques in first-time users. Methods: We conducted a single-center prospective study involving 100 consecutive patients with symptomatic atrial fibrillation who underwent first-time PVI using either size-adjustable CB PVI or PFA PVI from July 2023 to March 2024. Results: Acute PVI was achieved in 100% of patients in both groups. First-pass isolation (FPI) was more frequently achieved in the PFA group compared to the size-adjustable CB group. The mean procedural duration and fluoroscopy dose were significantly shorter in the PFA cohort (p < 0.001). Furthermore, a significant reduction in fluoroscopy time was observed during the learning curve within the PFA group (p = 0.023). There were no major complications in both groups. Conclusions: Both systems demonstrate good effectiveness and safety during PVI performed by first-time users. However, the PFA group exhibited a significantly shorter procedural duration.

Initial experience with ablation of ventricular arrhythmias using a pulsed-field system

Abstract Introduction Catheter ablation using radiofrequency (RF) current is a well-established method of treatment of ventricular arrhythmias (VA). However, RF ablation may fail to eliminate deeply located arrhythmogenic substrate. Pulsed-field (PF) is a novel energy source with a potential to create deeper lesions, especially in scar tissue. Purpose This study aims to present the data on safety and efficacy (acute outcome data) of VA ablation using PF. Methods The population consists of 15patients (5 women, age: 61 ± 19years) after previously failed RF ablation of VA. The underlying condition was nonischemic cardiomyopathy (53%), coronary artery disease (13%), and congenital heart disease (13%), respectively. No structural heart disease was present in 20% of cases. The mean left ventricular ejection fraction was 39 ± 13%. Eighty percent of patients had sustained VA, the remaining patients presented with frequent ventricular ectopy. Ablation was performed using a conventional irrigated 4-mm tip catheter in a combination with commercially available PF generator. Peripheral venous blood samples for the assessment of the plasmatic levels of high-sensitivity troponin T (hsTnT) were obtained the next day (usually 18-24hours) after the procedure. Results A mean of 17±12 PF applications (25A) per patient were delivered. In 5 patients (33%), an additional RF ablation (4±9 applications) was performed. Acute success as assessed by non-inducibility of VA or elimination of ectopic focus was achieved in all but one patient (93%). In 4 cases (27%), PF energy was applied within the great cardiac vein and subsequent coronary angiography did not reveal any abnormality. On the other hand, transient conduction system block occurred in 3 cases (20%) during PF application on the lateral LV wall remotely from the LV septum (complete AV block in one, LBBB in two patients). These events resolved in all cases within one hour. Ablation using PF did not result in excessive increase of hsTnT (657±482ng/l, with upper reference level of 14ng/l). Conclusion Initial experience with PF for the treatment of VA indicates high acute efficacy. The long-term effect is to be determined. PF applications in the ventricle may be associated with unexpected but transient conduction system damage, even when applications are performed remotely from the interventricular septum. The postprocedural increase in plasma troponin levels is only moderate.