Comparison between high-frequency irreversible electroporation and irreversible electroporation ablation of small swine liver

277 Background: Irreversible electroporation unlike ablation is excellent in inducing cell death via apoptosis. It, however, has disadvantages of electrical conduction via cardiac and nervous tissue. This results in requiring cardiac monitoring and general anesthesia and paralytics while performing electroporation. We hypothesized a novel high-frequency IRE (H-FIRE) system employing ultra-short bipolar pulses would obviate the need for cardiac synchronization and paralytics while maintaining measurable effect on cell death. Methods: Female swine (55-65Kg) were used. Two H-FIRE electrodes were inserted into the liver (1.5-cm spacing). In the absence of paralytics H-FIRE pulses were delivered (2250V, 2-5-2 pulse configuration) at different on times (100 vs. 200μs) or number of pulses (100 vs. 300). Next electrodes were placed across major hepatic vascular structures and H-FIRE performed. At conclusion tissue was resected and analyzed histologically. Results: 24 H-FIREs were performed (mean ablation time 275 secs). No EKG abnormalities or changes in vital signs were measured during H-FIRE procedures. In 1/24 H-FIREs minor twitching of the rectus abdominis was recorded coinciding with pulse delivery. Histologically, tissues had effective electroporation as evidenced by cell death and caspase activity. Blinded scoring was performed for necrosis and apoptosis. Areas of cell death were predictable. No significant vascular damage or coagulated/thermally-desiccated blood was detected within major vessels following H-FIRE. Conclusions: H-FIRE is a novel way of liver electroporation. It produces predictable cell apoptosis without the requirement of paralytics and alteration of electrocardiographic signals as compared to traditional electroporation, while preserving underlying vascular integrity. Its application in cancer cell death needs to be further studied, but it has a potential for clinical use in targeting tumors with minimal morbidity and associated cardiac and neurologic side effects.

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High-Frequency Irreversible Electroporation for Intracranial Meningioma: A Feasibility Study in a Spontaneous Canine Tumor Model

Technology in Cancer Research & Treatment ◽

10.1177/1533033818785285 ◽

2018 ◽

Vol 17 ◽

pp. 153303381878528 ◽

Cited By ~ 16

Author(s):

Eduardo L. Latouche ◽

Christopher B. Arena ◽

Jill W. Ivey ◽

Paulo A. Garcia ◽

Theresa E. Pancotto ◽

...

Keyword(s):

Feasibility Study ◽

High Frequency ◽

Irreversible Electroporation ◽

Tumor Model ◽

Intracranial Meningioma ◽

Canine Tumor

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Cardiac impact of high-frequency irreversible electroporation using an asymmetrical waveform on liver in vivo

BMC Cardiovascular Disorders ◽

10.1186/s12872-021-02412-9 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Jing Li ◽

Jingjing Wang ◽

Xiaobo Zhang ◽

Xiao Zhang ◽

Hongmei Gao ◽

...

Keyword(s):

Muscle Relaxant ◽

High Frequency ◽

Liver Tissue ◽

Irreversible Electroporation ◽

Normal Liver ◽

Electrical Signal ◽

Cardiac Complications ◽

Cardiac Damage ◽

Electrical Pulses

Abstract Background High-Frequency Irreversible Electroporation (H-FIRE) is a novel technology for non-thermal ablation. Different from Irreversible electroporation (IRE), H-FIRE delivers bipolar electrical pulses without muscle contraction and does not cause electrolysis. Currently, little is known regarding the cardiac safety during the administration of H-FIRE on liver. The aim of this study was to evaluate the changes of electrocardiogram (ECG) and biomarkers of cardiac damage during asymmetrical waveform of H-FIRE therapy in vivo. Methods The swines (n = 7) in IRE group, which used 100 pulses (2200 V, 100–100 μs configuration), were administrated with muscle relaxant under anesthesia. In the absence of muscle relaxant, 7 swines in H-FIRE group were performed with 2400 pulses (3000 V, 5–3–3–5 μs configuration). Midazolam (0.5 mg/kg) and xylazine hydrochloride (20 mg/kg) were given to induce sedation, followed by Isoflurane (2.5%, 100% oxygen, 3 L/min) to maintain sedation in all the swines. Limb lead ECG recordings were analyzed by two electrophysiologists to judge the arrhythmia. Cardiac and liver tissue was examined by pathology technique. Results The ablation zones were larger in H-FIRE than IRE. Both IRE and H-FIRE did not affect the autonomous cardiac rhythm. Even when the electrical signal of IRE and H-FIRE fell on ventricular vulnerable period. Moreover, cTnI in IRE group showed an increase in 4 h after ablation, and decreased to baseline 72 h after ablation. However, cTnI showed no significant change during the administration of H-FIRE. Conclusions The study suggests an asymmetrical waveform for H-FIRE is a promising measure for liver ablation. The results were based on normal liver and the swines without potential cardiac diseases. With the limitations of these facts, asymmetrical waveform for H-FIRE of liver tissue seems relatively safe without major cardiac complications. The safety of asymmetrical waveform for H-FIRE needs to evaluate in future.

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Maximizing Local Access to Therapeutic Deliveries in Glioblastoma. Part III: Irreversible Electroporation and High-Frequency Irreversible Electroporation for the Eradication of Glioblastoma

Glioblastoma ◽

10.15586/codon.glioblastoma.2017.ch19 ◽

2017 ◽

pp. 373-393 ◽

Cited By ~ 1

Author(s):

MELVIN F. LORENZO ◽

◽

CHRISTOPHER B. ARENA ◽

RAFAEL V. DAVALOS ◽

◽

...

Keyword(s):

High Frequency ◽

Irreversible Electroporation ◽

Local Access

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Conductivity change with needle electrode during high frequency irreversible electroporation: a finite element study

Polish Journal of Medical Physics and Engineering ◽

10.2478/pjmpe-2019-0031 ◽

2019 ◽

Vol 25 (4) ◽

pp. 237-242

Author(s):

Amir Khorasani ◽

Seyed Mohammad Firoozabadi ◽

Zeinab Shankayi

Keyword(s):

Electrical Conductivity ◽

Electric Field ◽

Field Intensity ◽

High Frequency ◽

Pulse Width ◽

Electric Field Intensity ◽

Electric Field Distribution ◽

Irreversible Electroporation ◽

Tissue Conductivity ◽

Conductivity Change

Abstract Irreversible electroporation (IRE) is a process in which the cell membrane is damaged and leads to cell death. IRE has been used as a minimally invasive ablation tool. This process is affected by some factors. The most important factor is the electric field distribution inside the tissue. The electric field distribution depends on the electric pulse parameters and tissue properties, such as the electrical conductivity of tissue. The present study focuses on evaluating the tissue conductivity change due to high-frequency and low-voltage (HFLV) as well as low-frequency and high-voltage (LFHV) pulses during irreversible electroporation. We were used finite element analysis software, COMSOL Multiphysics 5.0, to calculate the conductivity change of the liver tissue. The HFLV pulses in this study involved 4000 bipolar and monopolar pulses with a frequency of 5 kHz, pulse width of 100 µs, and electric field intensity from 100 to 300 V/cm. On the other hand, the LFHV pulses, which we were used, included 8 bipolar and monopolar pulses with a frequency of 1 Hz, the pulse width of 2 ms and electric field intensity of 2500 V/cm. The results demonstrate that the conductivity change for LFHV pulses due to the greater electric field intensity was higher than for HFLV pulses. The most significant conclusion is the HFLV pulses can change tissue conductivity only in the vicinity of the tip of electrodes. While LFHV pulses change the electrical conductivity significantly in the tissue of between electrodes.

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