High-Frequency Irreversible Electroporation Using 5,000-V Waveforms to Create Reproducible 2- and 4-cm Ablation Zones—A Laboratory Investigation Using Mechanically Perfused Liver

• Published in: Journal of vascular and interventional radiology Vol. 31; no. 1; pp. 162 - 168.e7
• Main Authors: Kaufman, Jacob D., Fesmire, Christopher C., Petrella, Ross A., Fogle, Callie A., Xing, Lei, Gerber, David, Sano, Michael B.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-01-2020
• Subjects: PBS; IET; 4AA; H-FIRE; A+GP; IRE
• ISSN: 1051-0443; 1535-7732
• DOI: 10.1016/j.jvir.2019.05.009

To investigate if high-frequency irreversible electroporation (H-FIRE) treatments can be delivered at higher voltages and with greater energy delivery rates than currently implemented in clinical irreversible electroporation protocols.
Treatments using 3,000 V and 5,000 V were administered to mechanically perfused ex vivo porcine liver via a single applicator and grounding pad (A+GP) as well as a 4-applicator array (4AA). Integrated energized times (IET) 0.01–0.08 seconds and energy delivery rates 25–300 μs/s were investigated. Organs were preserved at 4°C for 10–15 hours before sectioning and gross analysis using a metabolic stain to identify the size and shape of ablation zones.
A+GP ablations measured between 1.6 cm and 2.2 cm, which did not increase when IET was increased from 0.02 seconds to 0.08 seconds (P > .055; range, 1.9–2.1 cm). Changes in tissue color and texture consistent with thermal damage were observed for treatments with energy delivery rates 50–300 μs/s, but not for treatments delivered at 25 μs/s. Use of the 4AA with a 3-cm applicator spacing resulted in ablations measuring 4.4–4.9 cm with energy delivery times of 7–80 minutes.
H-FIRE treatments can rapidly and reproducibly create 2-cm ablations using an A+GP configuration. Treatments without thermal injury were produced at the expense of extended treatment times. More rapid treatments resulted in ablations with varying degrees of thermal injury within the H-FIRE ablation zone. Production of 4-cm ablations is possible using a 4AA.