Artigos de revistas: "Pulsed Field Ablation"

1

Guttipatti, Pavithran, Najla Saadallah e Elaine Y. Wan. "Pulsed Field Ablation for the Treatment of Atrial Fibrillation: A Review and a Look into its Future". Heart Surgery Forum 27, n.º 2 (22 de fevereiro de 2024): E169—E179. http://dx.doi.org/10.59958/hsf.7141.

Texto completo da fonte

Resumo:

Pulsed field ablation (PFA) is a novel technology to treat atrial fibrillation (AF) utilizing electric fields to induce nonthermal irreversible electroporation of electrically active cardiac tissue to induce cardiac cell death. PFA offers improved safety benefits compared to traditional radiofrequency ablation (RFA) and cryoablation by specifically ablating only cardiac tissue. However, there are avenues for further optimization including neurological risk associated with microbubble formation and left atrial function post ablation. Various PFA devices with different electric pulse waveforms have been studied and tested in human trials, with the majority utilizing microsecond duration pulses. Shorter nanosecond duration pulses, or nanosecond PFA, is beginning to be studied for AF ablation. In this review we will delve into current waveforms used for PFA, areas for improvement, mechanisms behind nanosecond PFA, and its clinical impact for cardiac ablation.

Estilos ABNT, Harvard, Vancouver, APA, etc.

2

Reinsch, Nico, Anna Füting, Dennis Höwel e Kars Neven. "„Pulsed field ablation“". Herzschrittmachertherapie + Elektrophysiologie 33, n.º 1 (7 de janeiro de 2022): 12–18. http://dx.doi.org/10.1007/s00399-021-00833-9.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

3

Bourier, Felix. "Pulsed-Field-Ablation". CardioVasc 23, n.º 2 (31 de março de 2023): 30–32. http://dx.doi.org/10.1007/s15027-023-2967-z.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

4

Ferencz, Arnold Béla, Zoltán Salló, László Gellér e Nándor Szegedi. "Pulsed field ablation – Elektroporáció". Cardiologia Hungarica 54, n.º 2 (2024): 104–9. http://dx.doi.org/10.26430/chungarica.2024.54.2.104.

Texto completo da fonte

Resumo:

A pitvarfibrilláció (AF) a leggyakoribb szívritmuszavar, amelynek kezelésében elsődleges szerepet a tüdővéna-izoláció (pulmonálisvéna-izoláció, PVI) játszik. A PVI ma már biztonságos és hatékony beavatkozásként tartható számon. Rendszerint eddig a PVI-t a termikus energia segítségével végeztük (krio-, illetve rádiófrekvenciás abláció). A pulsed field abláció (PFA), azaz elektroporáció egy új, nem termikus energiát használó abláció, amely során kialakuló elektromos mező a szívizomsejtek szelektív károsításához vezet. A preklinikai vizsgálatok kitérnek a PFA-lézió létrehozásának biztonságosságára, szövettani képek által is bizonyítva a szívizom szelektív ablációját a környező szövetek ép struktúrájának megtartása mellett. A klinikai vizsgálatok során vizsgálták a különböző rendszerek, illetve az ezekhez tartozó katétereket, segítségével elvégzett PVI-k hosszú távú hatásosságát. A klinikai vizsgálatok során alkalmazott utánkövetési módszerek nem voltak egységesek, némely klinikai vizsgálatban akár invazív bal pitvari újratérképezést végeztek. Másokban csak a klinikai, vagyis tünet-, illetve panaszorientált utánkövetést választották, kiegészítve noninvazív vizsgálatokkal (EKG meghatározott időben, illetve Holter-EKG), így megkapva a ritmuszavarmentesség arányát.

Estilos ABNT, Harvard, Vancouver, APA, etc.

5

Zhao, Zhihong, Yonggang Chen, Bin Wu, Gaodong Qiu, Liangjie Hong, Xinhua Chen e Xingwei Zhang. "Pulsed-Field Ablation Using a Novel Ablation-Mapping Integrated System for Pulmonary Vein Isolation—A Preliminary Animal Study". Journal of Cardiovascular Development and Disease 9, n.º 12 (29 de novembro de 2022): 425. http://dx.doi.org/10.3390/jcdd9120425.

Texto completo da fonte

Resumo:

Objective: The purpose of this study is to evaluate the preliminary safety and effect of a pulsed electric field (PEF) ablation system. Methods: The pulmonary veins (PVs) and superior vena cava (SVC) were isolated with the pulsed field ablation (PFA) system, which included a PEF generator and an electrode. The effects of PFA were investigated in six porcines using a novel circular catheter with combined functions (mapping/ablation) designed to work with a cardiac mapping system. The PEF generator delivered a train of biphasic pulsed electric pulses with a high amplitude (800–2000 V) and short pulse duration. The voltage mapping, PVs and SVC potentials, ostial diameters, and phrenic nerve and esophagus viability data were collected 4 weeks later, after which the animals were subsequently euthanized for gross histopathology analysis. Results: PFA 100% isolated the PVs and SVC with four applications with a mean pulse number of 100–150 pulses, causing no muscle convulsion. PFA does not cause PV stenosis or phrenic nerve dysfunction. Histological analysis confirmed 100% transmurally without any venous stenoses or phrenic injuries. Pathology follow-up showed that PFA had selectively ablated cardiomyocytes but spared blood vessels, the esophagus, and phrenic nerves; after ablation, the myocardial tissue showed homogeneous fibrosis. Conclusion: The PFA system is safe and feasible in the preliminary porcine model, which can effectively isolate PVs and SVCs. Transmural tissue damage can be achieved without phrenic palsy or stenosis.

Estilos ABNT, Harvard, Vancouver, APA, etc.

6

Fried, Daniel, Toshimoto Kushida, Gene P. Reck e Erhard W. Rothe. "YO A2II1/2,3/2 Vibrational State Distributions Measured after the Excimer Laser Ablation of Y2O3 Using a Laser-Initiated Pulsed Discharge as a Probe". Applied Spectroscopy 48, n.º 2 (fevereiro de 1994): 248–51. http://dx.doi.org/10.1366/0003702944028380.

Texto completo da fonte

Resumo:

The vibrational populations of the YO A2II- X2Σ system of YO were measured in the plasmas generated after the excimer laser ablation of Y2O3 in oxygen when both continuous and pulsed electric fields were applied. When an electric field is applied antiparallel to the direction of propagation of the ejected electrons, two luminous plumes appear, separated by several microseconds. The measured vibrational populations of the YO A2II- X2Σ system are different for each plume. The YO A2II populations were nonthermal in the first plume, representing emission from chemiluminescent reactive collisions in the plume after ablation. The second emission pulse, initiated by the discharge of a high-voltage capacitor, probes the ground-state YO in the plume via electron collisions. This pulsed electric field holds promise as a diagnostic probe of the ground-state species emitted in laser ablative processes.

Estilos ABNT, Harvard, Vancouver, APA, etc.

7

Defaye, Pascal, e Sandrine Venier. "Hemolysis During Pulsed-Field Ablation". JACC: Clinical Electrophysiology 10, n.º 7 (julho de 2024): 1672–74. http://dx.doi.org/10.1016/j.jacep.2024.06.007.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

8

Stephen J, Beebe. "Considerations for Exploring Nanosecond Pulsed Electric Fields (nsPEFs) for Treatments of Cancer, Benign Skin Diseases, Atrial Fibrillation, and for New Mechanistic Understandings". Records of Cell & Bioscience 1, n.º 1 (27 de setembro de 2024): 001–7. http://dx.doi.org/10.17352/rcb.000001.

Texto completo da fonte

Resumo:

Pulsed power includes acquiring electrical energy, compressing it, and releasing it in instantaneous bursts that are low in energy but very high in power. When the pulse duration is near the plasma membrane charging time constant, which is the time during which the cell interior is exposed to the applied pulsed electric field, it affects intracellular structures and functions. The technology is called nanosecond Pulsed Electric Fields (nsPEFs), nanosecond electric pulses (nsEP), or Nanopulse Stimulation (NPSTM) according to Pulse Biosciences, Inc., a company taking the technology to the market. Initial studies showed the elimination of tumor cells in vitro by apoptosis, and other regulated cell death mechanisms, elimination of rodent and canine osteosarcoma, and a basal cell carcinoma clinical trial. In the rat liver and mouse breast cancers, tumor-free animals were in situ vaccinated (ISV), preventing the recurrence of the treated cancers. The technology has also focused on treating benign skin diseases, with some advantages over cryoablation. More recently, the same technology called nanosecond pulsed-field ablation (nsPFA) has been used to treat cardiac arrhythmias like Atrial Fabulation (AFib) with catheters in humans. In pre-clinical studies and now in humans, this technology is showing advantages over radiofrequency ablation and cryoablation. On a new mechanistic landscape, nonlethal nsPEFs modulation of electron transport in the plasma membrane and the mitochondria show potential for controlling redox homeostasis and metabolism. Furthermore, different nsPEF waveforms have different effects on cells; waveforms can differ by pulse duration, rise time, electric field, and/or post-pulse features. So, for nsPEFs, there is a lethal side used for ablation as with NPS and nsPFA and a more recently recognized nonlethal side indicating new possibilities to differentially modify cell physiology depending on the different nsPEF waveforms.

Estilos ABNT, Harvard, Vancouver, APA, etc.

9

Qiu, Jie, Meiyan Dai, Yang Bai e Guangzhi Chen. "Potential Application of Pulsed Field Ablation in Ventricular Arrhythmias". Medicina 59, n.º 4 (7 de abril de 2023): 723. http://dx.doi.org/10.3390/medicina59040723.

Texto completo da fonte

Resumo:

Pulsed field ablation (PFA) is a new ablative method for the therapy of arrhythmia. Recent preclinical and clinical studies have already demonstrated the feasibility and safety of PFA for the treatment of atrial fibrillation (AF). However, the application of PFA may not be limited to the above fields. There are some data on the application of PFA on ventricular arrhythmias (VAs), such as ventricular fibrillation (VF) and ventricular tachycardia (VT). Further, a case report about PFA has been published recently, in which PFA was successfully applied to the ablation of premature ventricular contractions (PVCs) from the right ventricular outflow tract. Thus, we aimed to review recent research findings of PFA in ventricular ablation and evaluate the possibility of its application in VAs.

Estilos ABNT, Harvard, Vancouver, APA, etc.

10

Wojtaszczyk, Adam, Paweł Ptaszyński e Krzysztof Kaczmarek. "Pulsed field ablation – new perspective in atrial fibrillation therapy". In a good rythm 1, n.º 58 (31 de maio de 2021): 4–7. http://dx.doi.org/10.5604/01.3001.0015.0102.

Texto completo da fonte

Resumo:

Atrial fibrillation (AF) is one of the most important problems in cardiology. Thermal ablation therapies are “gold standard” to treat symptomatic patients. Despite the improvements, both success rate and safety are limited by their thermal nature. Pulsed filed ablation is a new non-thermal ablation method. It is based on the phenomenon of unrecoverable permeabilization of cell membranes caused by pulses of high voltage (irreversible electroporation). Several preclinical studies suggest its safety. Clinical trials published so far have showed high efficacy. Further studies especially with longer follow-up period are needed.

Estilos ABNT, Harvard, Vancouver, APA, etc.

11

O’Brien, Barry, John Reilly, Ken Coffey, Ana González-Suárez, Piotr Buchta, Piotr P. Buszman, Karolina Lukasik, Jason Tri, Martin van Zyl e Samuel Asirvatham. "Epicardial Pulsed Field Ablation of Ganglionated Plexi: Computational and Pre-Clinical Evaluation of a Bipolar Sub-Xiphoid Catheter for the Treatment of Atrial Fibrillation". Bioengineering 11, n.º 1 (24 de dezembro de 2023): 18. http://dx.doi.org/10.3390/bioengineering11010018.

Texto completo da fonte

Resumo:

Epicardial pulsed field ablation (PFA) of ganglionated plexi (GPs) is being explored as a potential treatment for atrial fibrillation. Initial work using open-chest access with a monopolar ablation device has been completed. This study describes the early development work for a device that can be used with subxiphoid access and deliver bipolar ablation pulses. Electric field computational models have been used for the initial guidance on pulse parameters. An in vivo assessment of these ablation parameters has been performed in an open-chest canine study, while subxiphoid access and navigation of the device has been demonstrated in a porcine model. Results from this acute study have demonstrated the promising potential of this approach.

Estilos ABNT, Harvard, Vancouver, APA, etc.

12

Ruwald, Martin H., Arne Johannessen, Morten Lock Hansen, Rene Worck e Jim Hansen. "Pulsed field ablation of the cavotricuspid isthmus using a multispline-electrode pulsed field ablation catheter". HeartRhythm Case Reports 8, n.º 3 (março de 2022): 147–50. http://dx.doi.org/10.1016/j.hrcr.2021.12.009.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

13

Ezzeddine, Fatima M., Samuel J. Asirvatham e Duy T. Nguyen. "Pulsed Field Ablation: A Comprehensive Update". Journal of Clinical Medicine 13, n.º 17 (1 de setembro de 2024): 5191. http://dx.doi.org/10.3390/jcm13175191.

Texto completo da fonte

Resumo:

One of the recent advancements in the field of cardiac electrophysiology is pulsed field ablation (PFA). PFA is a novel energy modality that does not rely on thermal processes to achieve ablation which, in turn, results in limited collateral damage to surrounding structures. In this review, we discuss the mechanisms, safety, efficacy, and clinical applications of PFA for the management of atrial and ventricular arrhythmias. We also summarize the published pre-clinical and clinical studies regarding this new technology.

Estilos ABNT, Harvard, Vancouver, APA, etc.

14

Mathuria, Nilesh. "Pulsed-Field Ablation for Atrial Fibrillation". JACC: Clinical Electrophysiology 7, n.º 5 (maio de 2021): 628–29. http://dx.doi.org/10.1016/j.jacep.2021.03.007.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

15

THAREJA, RAJ K., e A. K. SHARMA. "Reactive pulsed laser ablation: Plasma studies". Laser and Particle Beams 24, n.º 2 (junho de 2006): 311–20. http://dx.doi.org/10.1017/s0263034606060484.

Texto completo da fonte

Resumo:

We report on the pulsed laser ablation of aluminum (Al) plasma in presence of ambient nitrogen to understand the formation of aluminum nitride (AlN). Formation of carbon nitride (CN) and titanium oxide (TiO) by pulsed laser-ablation of graphite and titanium targets in presence of ambient nitrogen and oxygen is also compared. We discuss the dynamics of plasma expansion based on existing models, shock and drag models, and the plasma gas interface distortion, Rayleigh-Taylor instability at various ambient pressures of nitrogen. Since Rayleigh-Taylor instability may give rise to self-generated magnetic field in the plasma, an attempt is made to understand the mechanism of generation as well as the estimation of this field near the focal spot using the information from the images of the expanding plasma. This is the first time images of the expanding plume are used to estimate self generated magnetic fields. At the irradiance level used in the experiment the field is high very close to the target surface therefore we expect splitting of the energy levels thus giving rise to emissions that may be anisotropic in nature. We discuss the extent of anisotropy by measuring the degree of polarization using emission intensity in optical emission spectrum of selected Al III transition 4s2S1/2–4p2P3/2oat 569.6 nm using both nanosecond and picosecond pulses.

Estilos ABNT, Harvard, Vancouver, APA, etc.

16

Yavin, Hagai, Mark Prasad, Jonathan Gordon, Tolga Aksu e Henry D. Huang. "Contemporary Trends in Pulsed Field Ablation for Cardiac Arrhythmias". Journal of Cardiovascular Development and Disease 12, n.º 1 (30 de dezembro de 2024): 10. https://doi.org/10.3390/jcdd12010010.

Texto completo da fonte

Resumo:

Pulsed field ablation (PFA) is a catheter-based procedure that utilizes short high voltage and short-duration electrical field pulses to induce tissue injury. The last decade has yielded significant scientific progress and quickened interest in PFA as an energy modality leading to the emergence of the clinical use of PFA technologies for the treatment of atrial fibrillation. It is generally agreed that more research is needed to improve our biophysical understanding of PFA for clinical cardiac applications as well as its potential as a potential alternative energy source to thermal ablation modalities for the treatment of other arrhythmias. In this review, we discuss the available preclinical and clinical evidence for PFA for atrial fibrillation, developments for ventricular arrhythmia (VA) ablation, and future perspectives.

Estilos ABNT, Harvard, Vancouver, APA, etc.

17

Scuderi, Maria, Janja Dermol-Černe, Tina Batista Napotnik, Sebastien Chaigne, Olivier Bernus, David Benoist, Daniel C. Sigg, Lea Rems e Damijan Miklavčič. "Characterization of Experimentally Observed Complex Interplay between Pulse Duration, Electrical Field Strength, and Cell Orientation on Electroporation Outcome Using a Time-Dependent Nonlinear Numerical Model". Biomolecules 13, n.º 5 (23 de abril de 2023): 727. http://dx.doi.org/10.3390/biom13050727.

Texto completo da fonte

Resumo:

Electroporation is a biophysical phenomenon involving an increase in cell membrane permeability to molecules after a high-pulsed electric field is applied to the tissue. Currently, electroporation is being developed for non-thermal ablation of cardiac tissue to treat arrhythmias. Cardiomyocytes have been shown to be more affected by electroporation when oriented with their long axis parallel to the applied electric field. However, recent studies demonstrate that the preferentially affected orientation depends on the pulse parameters. To gain better insight into the influence of cell orientation on electroporation with different pulse parameters, we developed a time-dependent nonlinear numerical model where we calculated the induced transmembrane voltage and pores creation in the membrane due to electroporation. The numerical results show that the onset of electroporation is observed at lower electric field strengths for cells oriented parallel to the electric field for pulse durations ≥10 µs, and cells oriented perpendicular for pulse durations ~100 ns. For pulses of ~1 µs duration, electroporation is not very sensitive to cell orientation. Interestingly, as the electric field strength increases beyond the onset of electroporation, perpendicular cells become more affected irrespective of pulse duration. The results obtained using the developed time-dependent nonlinear model are corroborated by in vitro experimental measurements. Our study will contribute to the process of further development and optimization of pulsed-field ablation and gene therapy in cardiac treatments.

Estilos ABNT, Harvard, Vancouver, APA, etc.

18

Narkar, Akshay, Abouzar Kaboudian, Yasaman Ardershirpour, Maura Casciola, Tromondae K. Feaster e Ksenia Blinova. "In Vitro Assay Development to Study Pulse Field Ablation Outcome Using Solanum Tuberosum". International Journal of Molecular Sciences 25, n.º 16 (17 de agosto de 2024): 8967. http://dx.doi.org/10.3390/ijms25168967.

Texto completo da fonte

Resumo:

Exposing cells to intense and brief electric field pulses can modulate cell permeability, a phenomenon termed electroporation. When applied in medical treatments of diseases like cancer and cardiac arrhythmias, depending on level of cellular destruction, it is also referred to as irreversible electroporation (IRE) or Pulsed Field Ablation (PFA). For ablation device testing, several pulse parameters need to be characterized in a comprehensive manner to assess lesion boundary and efficacy. Overly aggressive voltages and application numbers increase animal burden. The potato tuber is a widely used initial model for the early testing of electroporation. The aim of this study is to characterize and refine bench testing for the ablation outcomes of PFA in this simplistic vegetal model. For in vitro assays, several pulse parameters like voltage, duration, and frequency were modulated to study effects not only on 2D ablation area but also 3D depth and volume. As PFA is a relatively new technology with minimal thermal effects, we also measured temperature changes before, during, and after ablation. Data from experiments were supplemented with in silico modeling to examine E-field distribution. We have estimated the irreversible electroporation threshold in Solanum Tuberosum to be at 240 V/cm. This bench testing platform can screen several pulse recipes at early stages of PFA device development in a rapid and high-throughput manner before proceeding to laborious trials for IRE medical devices.

Estilos ABNT, Harvard, Vancouver, APA, etc.

19

Esser, Axel T., Kyle C. Smith, T. R. Gowrishankar e James C. Weaver. "Towards Solid Tumor Treatment by Nanosecond Pulsed Electric Fields". Technology in Cancer Research & Treatment 8, n.º 4 (agosto de 2009): 289–306. http://dx.doi.org/10.1177/153303460900800406.

Texto completo da fonte

Resumo:

Local and drug-free solid tumor ablation by large nanosecond pulsed electric fields leads to supra-electroporation of all cellular membranes and has been observed to trigger nonthermal cell death by apoptosis. To establish pore-based effects as the underlying mechanism inducing apoptosis, we use a multicellular system model (spatial scale 100 μm) that has irregularly shaped liver cells and a multiscale liver tissue model (spatial scale 200 mm). Pore histograms for the multicellular model demonstrate the presence of only nanometer-sized pores due to nanosecond electric field pulses. The number of pores in the plasma membrane is such that the average tissue conductance during nanosecond electric field pulses is even higher than for longer irreversible electroporation pulses. It is shown, however, that these nanometer-sized pores, although numerous, only significantly change the permeability of the cellular membranes to small ions, but not to larger molecules. Tumor ablation by nanosecond pulsed electric fields causes small to moderate temperature increases. Thus, the underlying mechanism(s) that trigger cell death by apoptosis must be non-thermal electrical interactions, presumably leading to different ionic and molecular transport than for much longer irreversible electroporation pulses.

Estilos ABNT, Harvard, Vancouver, APA, etc.

20

Baykaner, Tina, Muhammad Fazal e Atul Verma. "Taking the “pulse” of pulsed‐field ablation: Real‐world experience". Journal of Cardiovascular Electrophysiology 33, n.º 3 (12 de janeiro de 2022): 357–59. http://dx.doi.org/10.1111/jce.15348.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

21

Gudvangen, Emily, Uma Mangalanathan, Iurii Semenov, Allen S. Kiester, Mark A. Keppler, Bennett L. Ibey, Joel N. Bixler e Andrei G. Pakhomov. "Pulsed Electric Field Ablation of Esophageal Malignancies and Mitigating Damage to Smooth Muscle: An In Vitro Study". International Journal of Molecular Sciences 24, n.º 3 (2 de fevereiro de 2023): 2854. http://dx.doi.org/10.3390/ijms24032854.

Texto completo da fonte

Resumo:

Cancer ablation therapies aim to be efficient while minimizing damage to healthy tissues. Nanosecond pulsed electric field (nsPEF) is a promising ablation modality because of its selectivity against certain cell types and reduced neuromuscular effects. We compared cell killing efficiency by PEF (100 pulses, 200 ns–10 µs duration, 10 Hz) in a panel of human esophageal cells (normal and pre-malignant epithelial and smooth muscle). Normal epithelial cells were less sensitive than the pre-malignant ones to unipolar PEF (15–20% higher LD50, p < 0.05). Smooth muscle cells (SMC) oriented randomly in the electric field were more sensitive, with 30–40% lower LD50 (p < 0.01). Trains of ten, 300-ns pulses at 10 kV/cm caused twofold weaker electroporative uptake of YO-PRO-1 dye in normal epithelial cells than in either pre-malignant cells or in SMC oriented perpendicularly to the field. Aligning SMC with the field reduced the dye uptake fourfold, along with a twofold reduction in Ca2+ transients. A 300-ns pulse induced a twofold smaller transmembrane potential in cells aligned with the field, making them less vulnerable to electroporation. We infer that damage to SMC from nsPEF ablation of esophageal malignancies can be minimized by applying the electric field parallel to the predominant SMC orientation.

Estilos ABNT, Harvard, Vancouver, APA, etc.

22

Xiong, Chang-Wei, Ching-Yen Ho e Dong-Kai Qiao. "Analysis of Direct Optical Ablation and Sequent Thermal Ablation for the Ultrashort Pulsed Laser Photo-Thermal Micromachining". Coatings 10, n.º 12 (25 de novembro de 2020): 1151. http://dx.doi.org/10.3390/coatings10121151.

Texto completo da fonte

Resumo:

An ultra-fast pulsed laser for materials processing can obtain submicrometer- to nanometer-sized parts or patterns (precision or accuracy) because the heat cannot diffuse in time for an ultra-fast pulsed duration, and this causes a threshold of ablation in multi-photoabsorption. The optical and thermal effects significantly affect the processing quality of an ultrashort pulsed laser for materials. This study utilizes a Laplace transform method to display the optical and thermal effects on the temperature field and the ablated depth of an ultrashort pulsed laser processing of materials. The results reveal that If an ultrafast pulsed laser-induced heat can keep the irradiated region above the evaporated temperature until the thermal diffusion occurs in the lattice of materials, thermal ablation occurs. The optical ablation can get a better processing quality due to less thermal diffusion. This study theoretically elucidates that the depth of optical ablation approximates the product of an optical absorption length and the logarithm of the ratio of laser fluence to laser fluence threshold. It has also been shown that the optical and thermal ablation, respectively, occur in low and high laser fluence because the optical ablation depends directly on the main source of the incident ultrashort pulsed laser. However, the thermal ablation is determined by the residual heat directly from the incident ultrashort pulsed laser after the optical ablation. The increase rate of the ablated depth per pulse with laser fluence is actually lower at high laser fluences than that at low laser fluences because the thermal ablation using the residual heat directly from the incident ultrashort pulsed laser is governed at high laser fluences. This study will provide the closed-form of a solution that elucidate the direct optical ablation and sequent thermal ablation for the ultra-fast pulsed laser photo-thermal processing.

Estilos ABNT, Harvard, Vancouver, APA, etc.

23

Pakhomova, Olga N., Eleni Zivla, Giedre Silkuniene, Mantas Silkunas e Andrei G. Pakhomov. "Potentiation of Gelonin Cytotoxicity by Pulsed Electric Fields". International Journal of Molecular Sciences 26, n.º 2 (8 de janeiro de 2025): 458. https://doi.org/10.3390/ijms26020458.

Texto completo da fonte

Resumo:

Gelonin is a ribosome-inactivating protein with extreme intracellular toxicity but poor permeation into cells. Targeted disruption of cell membranes to facilitate gelonin entry is explored for cancer and tissue ablation. We demonstrate a hundreds- to thousands-fold enhancement of gelonin cytotoxicity by pulsed electric fields in the T24, U-87, and CT26 cell lines. The effective gelonin concentration to kill 50% of cells (EC50) after electroporation ranged from <1 nM to about 100 nM. For intact cells, the EC50 was unattainable even at the highest gelonin concentration of 1000 nM, which reduced cell survival by only 5–15%. For isoeffective electroporation treatments using 300 ns, 9 µs, and 100 µs pulses, longer pulses were more efficient at lowering gelonin EC50. Increasing the electric field strength of 8, 100 µs pulses from 0.65 to 1.25 kV/cm reduced gelonin EC50 from 128 nM to 0.72 nM. Conversely, the presence of 100 nM gelonin enabled a more than 20-fold reduction in the number of pulses required for equivalent cell killing. Pulsed electric field-mediated delivery of gelonin shows promise for hyperplasia ablation at concentrations sufficiently low to minimize or avoid systemic toxicity.

Estilos ABNT, Harvard, Vancouver, APA, etc.

24

Weyand, Sebastian, Viola Adam, Paloma Biehler, Patricia Hägele, Simon Hanger, David Heinzmann, Stephanie Löbig, Andrei Pinchuk, Christian Waechter e Peter Seizer. "Focal Pulsed Field Ablation for Atrial Arrhythmias: Efficacy and Safety under Deep Sedation". Journal of Clinical Medicine 13, n.º 2 (19 de janeiro de 2024): 576. http://dx.doi.org/10.3390/jcm13020576.

Texto completo da fonte

Resumo:

Focal pulsed field ablation (PFA) is a novel technique for treating cardiac arrhythmias. It has demonstrated positive results in initial studies and has a good safety profile. In recent studies, PFA was often utilized for first-time pulmonary vein isolation (PVI) and was performed under general anesthesia. In our study, we assessed the feasibility, safety, acute procedural efficacy, and efficiency of focal PFA under deep sedation in patients, 80% of whom had undergone at least one left atrial ablation previously. We treated 30 patients (71 ± 7, 46% male) using the CENTAURI system for various atrial arrhythmias, including atrial fibrillation, typical and atypical atrial flutter, and focal atrial tachycardia. The average procedure and fluoroscopy times were 122 ± 43 min and 9 ± 7 min, respectively. A total of 83.33% of patients received additional line ablations beyond PVI, specifically targeting the posterior box and anterior mitral line. All ablations were successfully performed in deep sedation with only one major and one minor complication observed. The major complication was a vasospasm of the right coronary artery during ablation of the cavotricuspid isthmus, which was treated successfully with intracoronary nitroglycerin. All patients could be discharged in sinus rhythm. Moreover, adenosine appears effective in identifying dormant conduction in some patients after focal PFA. In conclusion, focal PFA is an effective approach for complex left atrial ablations under deep sedation, offering both high efficacy and efficiency with a reliable safety profile. Studies on long-term outcomes are needed.

Estilos ABNT, Harvard, Vancouver, APA, etc.

25

Reddy, Vivek Y., Srinivas R. Dukkipati, Petr Neuzil, Ante Anic, Jan Petru, Moritoshi Funasako, Hubert Cochet et al. "Pulsed Field Ablation of Paroxysmal Atrial Fibrillation". JACC: Clinical Electrophysiology 7, n.º 5 (maio de 2021): 614–27. http://dx.doi.org/10.1016/j.jacep.2021.02.014.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

26

Lindemann, F., S. Nedios, T. Seewöster e G. Hindricks. "Pulmonalvenenisolation bei Vorhofflimmern mittels „pulsed field ablation“". Herz 46, n.º 4 (17 de junho de 2021): 318–22. http://dx.doi.org/10.1007/s00059-021-05047-w.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

27

Futyma, Piotr, e Piotr Kułakowski. "Pulsed Field Ablation for Persistent Atrial Fibrillation". Journal of the American College of Cardiology 76, n.º 25 (dezembro de 2020): 3064–65. http://dx.doi.org/10.1016/j.jacc.2020.10.045.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

28

Wilber, David J. "Pulsed-Field Ablation and the Coronary Arteries". JACC: Clinical Electrophysiology 8, n.º 12 (dezembro de 2022): 1497–99. http://dx.doi.org/10.1016/j.jacep.2022.11.006.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

29

Overbeck, Peter. "Die Pulsed-Field-Ablation in der Routinepraxis". CardioVasc 23, n.º 3 (junho de 2023): 8–9. http://dx.doi.org/10.1007/s15027-023-3036-3.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

30

Anic, Ante. "Top stories on pulsed field ablation (2024)". Heart Rhythm 21, n.º 5 (maio de 2024): 705–6. http://dx.doi.org/10.1016/j.hrthm.2024.01.029.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

31

Yu, Fengyuan, e Min Tang. "Pulsed Field Ablation in the Treatment of Cardiac Arrhythmias: A State-of-the-art Review". International Journal of Heart Rhythm 9, n.º 1 (janeiro de 2024): 12–18. http://dx.doi.org/10.4103/ijhr.ijhr_6_24.

Texto completo da fonte

Resumo:

Abstract Pulsed-field ablation (PFA), specifically irreversible electroporation, induces cell membrane damage through the formation of irreversible pores, leading to apoptosis and necrosis, with applications in tumor treatment and myocardium ablation since 2007. This review is on PFA in the treatment of cardiac arrhythmias, including the basic principles, clinical applications, and hot issues of PFA. Presently, the pulsed electric field has demonstrated its effectiveness and safety in the treatment of atrial fibrillation, which is not inferior to that of traditional thermal energy. Research and application on pulsed electric ablation is rapidly advancing due to its advantages of rapidity and specificity in lesion creation. Moreover, pulsed electric ablation has reduced the difficulty of catheter manipulation in pulmonary vein isolation, making it an available treatment to benefit more patients.

Estilos ABNT, Harvard, Vancouver, APA, etc.

32

Carta-Bergaz, Alejandro, Gonzalo R. Ríos-Muñoz, Pablo Ávila, Felipe Atienza, Esteban González-Torrecilla e Ángel Arenal. "Pulsed Field Ablation of Atrial Fibrillation: A Novel Technology for Safer and Faster Ablation". Biomedicines 12, n.º 10 (30 de setembro de 2024): 2232. http://dx.doi.org/10.3390/biomedicines12102232.

Texto completo da fonte

Resumo:

Atrial fibrillation (AF), the most common arrhythmia, is associated with increased morbidity, mortality, and healthcare costs. Evidence indicates that rhythm control offers superior cardiovascular outcomes compared to rate control, especially when initiated early after the diagnosis of AF. Catheter ablation remains the single best therapy for AF; however, it is not free from severe complications and only a small percentage of AF patients in the Western world ultimately receive ablation. Ensuring that AF ablation is safe, effective, and efficient is essential to make it accessible to all patients. With the limitations of traditional thermal ablative energies, pulsed field ablation (PFA) has emerged as a novel non-thermal energy source. PFA targets irreversible electroporation of cardiomyocytes to achieve cell death without damaging adjacent structures. Through its capability to create rapid, selective lesions in myocytes, PFA presents a promising alternative, offering enhanced safety, reduced procedural times, and comparable, if not superior, efficacy to thermal energies. The surge of new evidence makes it challenging to stay updated and understand the possibilities and challenges of PFA. This review aims to summarize the most significant advantages of PFA and how this has translated to the clinical arena, where four different catheters have received CE-market approval for AF ablation. Further research is needed to explore whether adding new ablation targets, previously avoided due to risks associated with thermal energies, to pulmonary vein isolation can improve the efficacy of AF ablation. It also remains to see whether a class effect exists or if different PFA technologies can yield distinct clinical outcomes given that the optimization of PFA parameters has largely been empirical.

Estilos ABNT, Harvard, Vancouver, APA, etc.

33

Lorenzo, Melvin F., Sabrina N. Campelo, Julio P. Arroyo, Kenneth N. Aycock, Jonathan Hinckley, Christopher B. Arena, John H. Rossmeisl e Rafael V. Davalos. "An Investigation for Large Volume, Focal Blood-Brain Barrier Disruption with High-Frequency Pulsed Electric Fields". Pharmaceuticals 14, n.º 12 (20 de dezembro de 2021): 1333. http://dx.doi.org/10.3390/ph14121333.

Texto completo da fonte

Resumo:

The treatment of CNS disorders suffers from the inability to deliver large therapeutic agents to the brain parenchyma due to protection from the blood-brain barrier (BBB). Herein, we investigated high-frequency pulsed electric field (HF-PEF) therapy of various pulse widths and interphase delays for BBB disruption while selectively minimizing cell ablation. Eighteen male Fisher rats underwent craniectomy procedures and two blunt-tipped electrodes were advanced into the brain for pulsing. BBB disruption was verified with contrast T1W MRI and pathologically with Evans blue dye. High-frequency irreversible electroporation cell death of healthy rodent astrocytes was investigated in vitro using a collagen hydrogel tissue mimic. Numerical analysis was conducted to determine the electric fields in which BBB disruption and cell ablation occur. Differences between the BBB disruption and ablation thresholds for each waveform are as follows: 2-2-2 μs (1028 V/cm), 5-2-5 μs (721 V/cm), 10-1-10 μs (547 V/cm), 2-5-2 μs (1043 V/cm), and 5-5-5 μs (751 V/cm). These data suggest that HF-PEFs can be fine-tuned to modulate the extent of cell death while maximizing peri-ablative BBB disruption. Furthermore, numerical modeling elucidated the diffuse field gradients of a single-needle grounding pad configuration to favor large-volume BBB disruption, while the monopolar probe configuration is more amenable to ablation and reversible electroporation effects.

Estilos ABNT, Harvard, Vancouver, APA, etc.

34

Maan, Abhishek, e Jacob Koruth. "Pulsed Field Ablation: a New Paradigm for Catheter Ablation of Arrhythmias". Current Cardiology Reports 24, n.º 2 (fevereiro de 2022): 103–8. http://dx.doi.org/10.1007/s11886-021-01630-z.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

35

Yang, Enbo, Joy Li, Michael Cho e Shu Xiao. "Cell Fragmentation and Permeabilization by a 1 ns Pulse Driven Triple-Point Electrode". BioMed Research International 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/4072983.

Texto completo da fonte

Resumo:

Ultrashort electric pulses (ns-ps) are useful in gaining understanding as to how pulsed electric fields act upon biological cells, but the electric field intensity to induce biological responses is typically higher than longer pulses and therefore a high voltage ultrashort pulse generator is required. To deliver 1 ns pulses with sufficient electric field but at a relatively low voltage, we used a glass-encapsulated tungsten wire triple-point electrode (TPE) at the interface among glass, tungsten wire, and water when it is immersed in water. A high electric field (2 MV/cm) can be created when pulses are applied. However, such a high electric field was found to cause bubble emission and temperature rise in the water near the electrode. They can be attributed to Joule heating near the electrode. Adherent cells on a cover slip treated by the combination of these stimuli showed two major effects: (1) cells in a crater (<100 μm from electrode) were fragmented and the debris was blown away. The principal mechanism for the damage is presumed to be shear forces due to bubble collapse; and (2) cells in the periphery of the crater were permeabilized, which was due to the combination of bubble movement and microstreaming as well as pulsed electric fields. These results show that ultrashort electric fields assisted by microbubbles can cause significant cell response and therefore a triple-point electrode is a useful ablation tool for applications that require submillimeter precision.

Estilos ABNT, Harvard, Vancouver, APA, etc.

36

Matthee, Ashton, Zahra Aghababaie, Linley A. Nisbet, Jarrah M. Dowrick, John A. Windsor, Gregory B. Sands e Timothy R. Angeli-Gordon. "Pulsed-field ablation: An alternative ablative method for gastric electrophysiological intervention." American Journal of Physiology-Gastrointestinal and Liver Physiology, 16 de julho de 2024. http://dx.doi.org/10.1152/ajpgi.00124.2024.

Texto completo da fonte

Resumo:

Pulsed-field ablation (PFA) is an emerging ablative technology that has been used successfully to eliminate cardiac arrhythmias. As a non-thermal technique it has significant benefits over traditional radio-frequency ablation with improved target tissue specificity and reduced risk of adverse events during cardiac applications. We investigated whether PFA is safe for use in the stomach and whether it could modulate gastric slow waves. Female weaner pigs were fasted overnight before anesthesia was induced using tiletamine hydrochloride (50 mg mL-1) and zolazepam hydrochloride (50 mg mL-1) and maintained with propofol (Diprivan 2%, 0.2‑0.4 mg kg‑1 min‑1). Pulsed-field ablation was performed on their gastric serosa in vivo. Adjacent point lesions ( n=2-4) were used to create a linear injury using bipolar pulsed-field ablation consisting of 40 pulses (10 Hz frequency, 0.1 ms pulse width, 1000 V amplitude). High-resolution electrical mapping defined baseline and post-ablation gastric slow-wave patterns. A validated five-point scale was used to evaluate tissue damage in hematoxylin and eosin stained images. Results indicated that PFA successfully induced complete conduction blocks in all cases, with lesions through the entire thickness of the gastric muscle layers. Consistent post-ablation slow-wave patterns emerged immediately following ablation and persisted over the study period. Pulsed-field ablation induces rapid conduction blocks as a tool to modulate slow-wave patterns, indicating it may be suitable as an alternative to radio-frequency ablation.

Estilos ABNT, Harvard, Vancouver, APA, etc.

37

Bi, Shengyu, Fenglin Jia, Chang Lv, Qiang He, Xinyu Xu, Zhixiao Xue e Siying Su. "Preclinical Study of Biphasic Asymmetric Pulsed Field Ablation". Frontiers in Cardiovascular Medicine 9 (24 de março de 2022). http://dx.doi.org/10.3389/fcvm.2022.859480.

Texto completo da fonte

Resumo:

Pulsed field ablation (PFA) is a novel method of pulmonary venous isolation in atrial fibrillation ablation and is featured by tissue-selective ablation. Isolation is achieved via the application of high-voltage microsecond pulses that create irreversible perforations in cell membranes (i.e., electroporation). We proposed a new biphasic asymmetric pulse mode and verified the lesion persistence and safety of this mode for pulmonary vein ostia ablation in preclinical studies. We found that biphasic asymmetric pulses can effectively reduce muscle contractions and drop ablation threshold. In the electroanatomic mapping, the ablation site showed a continuous low potential area, and the atrium was not captured after 30 days of pacing. Pathological staining showed that cardiomyocytes in the ablation area were replaced by fibroblasts and there was no damage outside the ablation zone. Our results show that pulmonary venous isolation using the biphasic asymmetric discharge mode is safe, durable, effective, and causes no damage to other tissues.

Estilos ABNT, Harvard, Vancouver, APA, etc.

38

Mercado Montoya, M., T. Gomez Bustamante, E. Kulstad, S. Mickelsen e A. Gonzalez Suarez. "Analysis of thermal effects from pulsed field ablation". European Heart Journal 44, Supplement_2 (novembro de 2023). http://dx.doi.org/10.1093/eurheartj/ehad655.381.

Texto completo da fonte

Resumo:

Abstract Background Pulsed field ablation (PFA) has been described as non-thermal, but abundant data exist in oncology applications [1-3], and growing data are emerging in cardiology [4], highlighting that thermal effects are in fact present with PFA. The particular parameters (such as voltage, pulse gap, pulse number) that most influence the development of thermal energy during PFA are less clear. Purpose We sought to evaluate the thermal effects arising from pulsed field ablation of myocardial and esophageal tissue over a range of typical peak voltage operating conditions. Methods Using a three-dimensional computer model of the left atrium and esophagus, we quantified the thermal effects from PFA applications over a range of peak voltage operating conditions (1 kV, 1.5 kV, and 2 kV). Bipolar electroporation was simulated using one electrode as the anode and the other as a grounded cathode. Far-field and symmetry boundaries were set as electrically insulating. A monophasic waveform with a pulse duration of 100 µs and pause between pulses of 1 s was applied for a total of 50 pulses in a single train. Myocardial thickness was 1.5 mm, esophageal thickness was 2 mm, and the pericardial fat layer was varied between 0.3 and 0.75 mm. Results Minimal temperature rise in the esophagus was seen with 1 kV pulses (corresponding to 13.4 J input). With 1.5 kV and 2 kV peak voltages (corresponding to 32.3 J and 66.2 J), temperature elevations reaching 46.3 °C and > 62 °C were seen, respectively. These elevations occurred after only a single pulse train of 50 pulses, implying that further elevations in temperature would be seen with subsequent applications. Conclusions Thermal effects from PFA depend on total energy deposited, of which peak voltage is an important component. Current commercially available systems appear to have the potential to induce collateral thermal injury, particularly with a thin pericardial fat layer, and with repeated applications of pulsed field energy.

Estilos ABNT, Harvard, Vancouver, APA, etc.

39

Mercado Montoya, M., T. Gomez Bustamante, M. Jessen, E. Kulstad, S. Mickelsen e L. Overzet. "Quantification of hemolysis rates from pulsed field ablation". European Heart Journal 45, Supplement_1 (outubro de 2024). http://dx.doi.org/10.1093/eurheartj/ehae666.387.

Texto completo da fonte

Resumo:

Abstract Introduction Pulsed electric fields induce hemolysis of red blood cells as a dose-dependent effect of the electric field. Voltage pulsations induce a transmembrane potential across the cell membrane and either open up or create pores in the red cells. In isotonic conditions, the pores allow passage of potassium and sodium ions but not sucrose or hemoglobin, and leakage of ions leads to an osmotic imbalance which in turn causes a colloidal hemolysis of the red cells. Objective To quantify hemolysis rates during pulsed field ablation (PFA). Methods We created a computational model of PFA to determine the total volume of blood hemolyzed from each pulse during catheter ablation using pulsed field energy. The percentage hemolysis was calculated as a function of electric field intensity utilizing existing published experimental data. A single electrode delivering a single pulse of 100 microseconds duration was modeled at voltages of 1 kV, 1.5 kV, and 2 kV. Results The total volume of hemolyzed blood per pulse increased with increasing applied voltage (Figure). For 2 electrodes in direct tissue contact, the electrode surface exposed to the blood pool generated 19 microliters of hemolyzed red blood cells with a single pulse of a 2 kV field strength. In the case of a single pulse train consisting of 50 pulses, using a catheter configuration with 20 electrodes, an estimate of total volume per pulse train is approximately 9.5 mL of hemolyzed blood. In the case of electrodes not in direct contact with endocardial tissue, and exposed to the blood pool, up to double this volume could be anticipated per pulse train. Hemolyzed volume can be reduced with better tissue contact (reducing exposure to blood), or potentially with the use of irrigation to dilute the local red blood cell concentration. Increased tonicity of the irrigant fluid may also reduce the osmotic pressure increases that result in hemolysis. Conclusions Typical voltages utilized in pulsed field ablation can cause significant hemolysis, which is exacerbated by inadequate tissue contact. A greater number of electrodes and number of pulses delivered increases the risk, whereas better tissue contact, and the use of irrigation, may reduce it.

Estilos ABNT, Harvard, Vancouver, APA, etc.

40

Reddy, Vivek Y., Elad Anter, Petr Peichl, Gediminas Rackauskas, Jan Petru, Moritoshi Funasako, Jacob S. Koruth et al. "First-in-Human Clinical Series of a Novel Conformable Large-Lattice Pulsed Field Ablation Catheter for Pulmonary Vein Isolation". Europace, 8 de abril de 2024. http://dx.doi.org/10.1093/europace/euae090.

Texto completo da fonte

Resumo:

Abstract Background/Aims Pulsed field ablation (PFA) has significant advantages over conventional thermal ablation of atrial fibrillation (AF). This first-in-human, single-arm trial to treat paroxysmal AF (PAF) assessed the efficiency, safety, pulmonary vein isolation (PVI) durability and one-year clinical effectiveness of an 8-Fr, large-lattice, conformable single-shot PFA catheter together with a dedicated electroanatomical mapping system. Methods After rendering the PV anatomy, the PFA catheter delivered monopolar, biphasic pulse trains (5-6 secs per application; ∼4 applications per PV). Three waveforms were tested: PULSE1, PULSE2 and PULSE3. Follow-up included ECGs, Holters at 6 and 12 months, and symptomatic and scheduled transtelephonic monitoring. The primary and secondary efficacy endpoints were acute PVI and post-blanking atrial arrhythmia recurrence, respectively. Invasive remapping was conducted ∼75 days post-ablation. Results At three centers, PVI was performed by five operators in 85 patients using PULSE1 (n=30), PULSE2 (n=20), and PULSE3 (n=35). Acute PVI was achieved in 100% of PVs using 3.9±1.4 PFA applications per PV. Overall procedure, transpired ablation, PFA catheter dwell and fluoroscopy times were 56.5±21.6, 10.0 ± 6.0, 19.1±9.3 and 5.7±3.9 min, respectively. No pre-defined primary safety events occurred. Upon remapping, PVI durability was 90% and 99% on a per vein basis for the total and PULSE3 cohort, respectively. The Kaplan-Meier estimate of one-year freedom from atrial arrhythmias was 81.8% (95% CI 70.2-89.2%) for the total, and 100% (95% CI 80.6-100%) for the PULSE3 cohort. Conclusion PVI utilizing a conformable single-shot PFA catheter to treat PAF was efficient, safe, and effective, with durable lesions demonstrated upon remapping.

Estilos ABNT, Harvard, Vancouver, APA, etc.

41

Yavin, Hagai, Erez Brem, Israel Zilberman, Ayelet Shapira-Daniels, Keshava Datta, Assaf Govari, Andres Altmann, Ante Anic, Oussama Wazni e Elad Anter. "Circular Multielectrode Pulsed Field Ablation Catheter Lasso Pulsed Field Ablation". Circulation: Arrhythmia and Electrophysiology 14, n.º 2 (fevereiro de 2021). http://dx.doi.org/10.1161/circep.120.009229.

Texto completo da fonte

Resumo:

Background: Pulsed field ablation (PFA) is a nonthermal energy with potential safety advantages over radiofrequency ablation. This study investigated a novel PFA system—a circular multielectrode catheter (PFA lasso) and a multichannel generator designed to work with Carto 3 mapping system. Methods: A 7.5F bidirectional circular catheter with 10 electrodes and variable expansion was designed for PFA (biphasic, 1800 Volts). This study included a total of 16 swine used to investigate the following 3 experimental aims: Aim 1 examined the feasibility to create a right atrial ablation line of block from the superior vena cava to the inferior vena cava. Aim 2 examined the effect of PFA on lesion maturation including durability after a 30-day survival period. Aim 3 examined the effect of high-intensity PFA (10 applications) on esophageal and phrenic nerve tissue in comparison to normal intensity radiofrequency ablation (1–2 applications). Histopathologic analysis of all cardiac, esophageal, and phrenic nerve tissue was performed. Results: Acute line of block was achieved in 12/12 swine (100%) and required a total PFA time of 14 seconds (interquartile range [IQR], 9–24.5) per line. Ablation line durability after 28±3 days was maintained in 11/12 (91.7%) swine. PFA resulted in transmural lesions in 179/183 (97.8%) sections and a median lesion width of 14.2 mm. High-intensity PFA (9 [IQR, 8–14] application) had no effect on the esophagus while standard intensity radiofrequency ablation (1.5 [IQR, 1–2] applications) resulted in deep esophageal tissue injury involving the muscularis propria and adventitia layers. High-intensity PFA (16 [IQR, 10–28] applications) has no effect on phrenic nerve function and structure while standard dose radiofrequency ablation (1.5 [IQR, 1–2] applications) resulted in acute phrenic nerve paralysis. Conclusions: In this preclinical model, a multielectrode circular catheter and multichannel generator produced durable atrial lesions with lower vulnerability to esophageal or phrenic nerve damage.

Estilos ABNT, Harvard, Vancouver, APA, etc.

42

Verma, Atul, Samuel J. Asivatham, Thomas Deneke, Quim Castellvi e Robert E. Neal. "Primer on Pulsed Electrical Field Ablation". Circulation: Arrhythmia and Electrophysiology 14, n.º 9 (setembro de 2021). http://dx.doi.org/10.1161/circep.121.010086.

Texto completo da fonte

Resumo:

Pulsed electrical field (PEF) energy is a promising technique for catheter ablation of cardiac arrhythmias. In this article, the key aspects that need to be considered for safe and effective PEF delivery are reviewed, and their impact on clinical feasibility is discussed. The most important benefit of PEF appears to be the ability to kill cells through mechanisms that do not alter stromal proteins, sparing sensitive structures to improve safety, without sacrificing cardiomyocyte ablation efficacy. Many parameters affect PEF treatment outcomes, including pulse intensity, waveform shape, and number of pulses, as well as electrode configuration and geometry. These physical and electrical characteristics must be titrated carefully to balance target tissue effects with collateral implications (muscle contraction, temperature rise, risk of electrical arcing events). It is important to note that any combination of parameters affecting PEF needs to be tested for clinical efficacy and safety. Applying PEF clinically requires knowledge of the fundamentals of this technology to exploit its opportunities and generate viable, durable health improvements for patients.

Estilos ABNT, Harvard, Vancouver, APA, etc.

43

Koruth, Jacob S., Kenji Kuroki, Iwanari Kawamura, Richard Brose, Raju Viswanathan, Eric D. Buck, Elina Donskoy, Petr Neuzil, Srinivas R. Dukkipati e Vivek Y. Reddy. "Pulsed Field Ablation Versus Radiofrequency Ablation". Circulation: Arrhythmia and Electrophysiology 13, n.º 3 (março de 2020). http://dx.doi.org/10.1161/circep.119.008303.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

44

Wang, Yujue, Tian’an Jiang, Liting Xie, Huiyang Wang, Jing Zhao, Lei Xu e Chengyu Fang. "Effect of pulsed field ablation on solid tumor cells and microenvironment". Frontiers in Oncology 12 (23 de agosto de 2022). http://dx.doi.org/10.3389/fonc.2022.899722.

Texto completo da fonte

Resumo:

Pulsed field ablation can increase membrane permeability and is an emerging non-thermal ablation. While ablating tumor tissues, electrical pulses not only act on the membrane structure of cells to cause irreversible electroporation, but also convert tumors into an immune active state, increase the permeability of microvessels, inhibit the proliferation of pathological blood vessels, and soften the extracellular matrix thereby inhibiting infiltrative tumor growth. Electrical pulses can alter the tumor microenvironment, making the inhibitory effect on the tumor not limited to short-term killing, but mobilizing the collective immune system to inhibit tumor growth and invasion together.

Estilos ABNT, Harvard, Vancouver, APA, etc.

45

Koruth, Jacob S., e Moritz Nies. "Ventricular Pulsed-Field Ablation". JACC: Clinical Electrophysiology, julho de 2023. http://dx.doi.org/10.1016/j.jacep.2023.05.021.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

46

Li, Xinzhong, Long Huang, Jianyong Li, Senlin Huang e Yuegang Wang. "Tricuspid isthmus ablation with pulsed-field power by linear catheter: a case report". European Heart Journal - Case Reports, 8 de dezembro de 2023. http://dx.doi.org/10.1093/ehjcr/ytad601.

Texto completo da fonte

Resumo:

Abstract Background Pulsed-field ablation using annular or petal-shaped catheters had been proven to be effective for achieving electrical isolation of pulmonary veins in patients with atrial fibrillation. However, the utilization of linear pulse-field power for treating atrial flutter has yet to been documented. Case summary In this report, we present a case involving the successful treatment of tricuspid isthmus dependent atrial flutter treated with a linear pulsed-field catheter. The patient, a 71-year-old male, presents with an ECG indicating atrial flutter. Subsequent electrophysiological examination reveals typical atrial flutter that is dependent on the cavo-tricuspid isthmus (CTI). This condition is successfully terminated through the application of linear pulsed-field ablation. Discussion This case represents a pioneering instance of CTI-dependent atrial flutter ablation utilizing linear pulse-field power. The innovative approach not only effectively treats the patient but also serves as a valuable reference for future applications of linear treatment with pulsed-field ablation.

Estilos ABNT, Harvard, Vancouver, APA, etc.

47

Wu Xiao-Dong, Chen Yan-Zhou, Han Rui, Guo Yu-Yi, Zhuang Jie e Shi Fu-Kun. "Study on the law of diffused bubbles generated by the high-voltage pulsed electric field in liquid". Acta Physica Sinica, 2023, 0. http://dx.doi.org/10.7498/aps.72.20230443.

Texto completo da fonte

Resumo:

Pulsed Electric Fields (PEFs) is a novel physical energy source for the treatment of atrial fibrillation and tumor ablation, which has advantages over traditional thermal ablation, such as non-thermal, short treatment time, tissue selectivity, and low contact pressure requirements. The diffusion bubbles generated during physical ablation may lead to gas embolism and silent cerebral events(SCE), with potential hazards such as tissue damage and cerebral ischemia. Previous studies have shown that the amount of bubbles generation is correlated with the electrical properties of the treated object, pulse parameters (pulse waveform, treatment time and input energy), and electrodes. The amount of bubbles are more significant at the cathode than at the anode, and the amount of bubbles positively correlates with the input energy. However, to the best of our knowledge, no studies have been conducted to investigate the impact of ablation pulse parameters on diffusion bubbles. Therefore, in our experiment, a platform for pulse generation and diffusion bubble observation was built, and the needle-ring electrode we made realized the capture and measurement of diffusion bubbles. Since pulses with voltage within 3kV and pulse width within 100µs are commonly used as ablation parameters for atrial fibrillation and tumor in Pulsed Field Ablation (PFA), the pulse widths of unipolar pulses were selected as 5µs, 10µs, 50µs, and 100µs, and the number of pulses applied is 1. The pulse voltage was determined according to the parameters commonly used in PFA and the simulation calculation of the field strength distribution of the needlering electrode. After determining the parameters, this experiment explicitly investigated the relationship between diffusion bubbles and solution conductivity, pulse voltage, pulse width, input energy, and other parameters. Meanwhile, the size distribution of diffusion bubbles under different operating conditions was statistically investigated. Besides, the possible causes of diffuse bubbles were also explored. We evaluate the amount of bubbles by measuring the cross-sectional area of the diffusion bubbles from a top-down perspective. The experimental results showed that:the area of diffusion bubbles generated in the liquid is positively correlated with pulse voltage and input energy; high conductivity and long pulse width can enhance the thermal effect and increase the area of diffusion bubbles; diffusion bubbles with a diameter size larger than 100 μm are easily generated under high conductivity and high pulse width conditions. By speculating on the results, the electrolytic reaction may be the main source of diffusion bubbles when the needle electrode is the cathode. This study is expected to optimize future pulsed electric field ablation parameters.

Estilos ABNT, Harvard, Vancouver, APA, etc.

48

Meng, Fanchao, Shuqi Jin e Nian Liu. "Cardiac selectivity in pulsed field ablation". Current Opinion in Cardiology, 28 de novembro de 2024. http://dx.doi.org/10.1097/hco.0000000000001183.

Texto completo da fonte

Resumo:

Purpose of review This review examines the selective cardiac injury induced by pulsed electric fields during atrial fibrillation ablation. It consolidates findings from both preclinical and clinical studies on cardiac selectivity and explores the potential mechanisms behind this selectivity. Recent findings Preclinical studies indicate that pulsed electric fields cause significantly more myocardial injury compared with other tissues. Clinical studies have similarly shown that complication rates for pulsed field ablation are notably lower than those for radiofrequency and cryoballoon ablation. Summary Pulsed field ablation demonstrates a notable selectivity for myocardial injury, likely because of the unique functional and metabolic characteristics of cardiomyocytes. This review delves into the underlying principles of cardiac selectivity and proposes future directions for improving this selectivity. It is important to note that while pulsed field ablation shows promise, its cardiac selectivity is not absolute, as some complications still occur, necessitating further research.

Estilos ABNT, Harvard, Vancouver, APA, etc.

49

Verma, Atul, David E. Haines, Lucas V. Boersma, Nitesh Sood, Andrea Natale, Francis E. Marchlinski, Hugh Calkins et al. "Pulsed Field Ablation for the Treatment of Atrial Fibrillation: PULSED AF Pivotal Trial". Circulation, 6 de março de 2023. http://dx.doi.org/10.1161/circulationaha.123.063988.

Texto completo da fonte

Resumo:

BACKGROUND: Pulsed field ablation uses electrical pulses to cause nonthermal irreversible electroporation and induce cardiac cell death. Pulsed field ablation may have effectiveness comparable to traditional catheter ablation while preventing thermally mediated complications. METHODS: The PULSED AF pivotal study (Pulsed Field Ablation to Irreversibly Electroporate Tissue and Treat AF) was a prospective, global, multicenter, nonrandomized, paired single-arm study in which patients with paroxysmal (n=150) or persistent (n=150) symptomatic atrial fibrillation (AF) refractory to class I or III antiarrhythmic drugs were treated with pulsed field ablation. All patients were monitored for 1 year using weekly and symptomatic transtelephonic monitoring; 3-, 6-, and 12-month ECGs; and 6- and 12-month 24-hour Holter monitoring. The primary effectiveness end point was freedom from a composite of acute procedural failure, arrhythmia recurrence, or antiarrhythmic escalation through 12 months, excluding a 3-month blanking period to allow recovery from the procedure. The primary safety end point was freedom from a composite of serious procedure- and device-related adverse events. Kaplan-Meier methods were used to evaluate the primary end points. RESULTS: Pulsed field ablation was shown to be effective at 1 year in 66.2% (95% CI, 57.9 to 73.2) of patients with paroxysmal AF and 55.1% (95% CI, 46.7 to 62.7) of patients with persistent AF. The primary safety end point occurred in 1 patient (0.7%; 95% CI, 0.1 to 4.6) in both the paroxysmal and persistent AF cohorts. CONCLUSIONS: PULSED AF demonstrated a low rate of primary safety adverse events (0.7%) and provided effectiveness consistent with established ablation technologies using a novel irreversible electroporation energy to treat patients with AF.

Estilos ABNT, Harvard, Vancouver, APA, etc.

50

Nakatani, Yosuke, Soumaya Sridi-Cheniti, Ghassen Cheniti, F. Daniel Ramirez, Cyril Goujeau, Clementine André, Takashi Nakashima et al. "Pulsed field ablation prevents chronic atrial fibrotic changes and restrictive mechanics after catheter ablation for atrial fibrillation". EP Europace, 8 de julho de 2021. http://dx.doi.org/10.1093/europace/euab155.

Texto completo da fonte

Resumo:

Abstract Aims Pulsed field ablation (PFA), a non-thermal ablative modality, may show different effects on the myocardial tissue compared to thermal ablation. Thus, this study aimed to compare the left atrial (LA) structural and mechanical characteristics after PFA vs. thermal ablation. Methods and results Cardiac magnetic resonance was performed pre-ablation, acutely (<3 h), and 3 months post-ablation in 41 patients with paroxysmal atrial fibrillation (AF) undergoing pulmonary vein (PV) isolation with PFA (n = 18) or thermal ablation (n = 23, 16 radiofrequency ablations, 7 cryoablations). Late gadolinium enhancement (LGE), T2-weighted, and cine images were analysed. In the acute stage, LGE volume was 60% larger after PFA vs. thermal ablation (P < 0.001), and oedema on T2 imaging was 20% smaller (P = 0.002). Tissue changes were more homogeneous after PFA than after thermal ablation, with no sign of microvascular damage or intramural haemorrhage. In the chronic stage, the majority of acute LGE had disappeared after PFA, whereas most LGE persisted after thermal ablation. The maximum strain on PV antra, the LA expansion index, and LA active emptying fraction declined acutely after both PFA and thermal ablation but recovered at the chronic stage only with PFA. Conclusion Pulsed field ablation induces large acute LGE without microvascular damage or intramural haemorrhage. Most LGE lesions disappear in the chronic stage, suggesting a specific reparative process involving less chronic fibrosis. This process may contribute to a preserved tissue compliance and LA reservoir and booster pump functions.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Artigos de revistas sobre o tema "Pulsed Field Ablation"

Crie uma referência precisa em APA, MLA, Chicago, Harvard, e outros estilos