Evaluation of a Novel Multielectrode Surgical Pulsed Field Ablation Clamp: An Ex-Vivo Vegetal Study

OBJECTIVES: At present, there is no commercially available surgical device to perform cardiac ablation utilizing pulsed field ablation (PFA). We sought to explore the efficacy and requirements of a novel PFA clamp to achieve transmural lesions in a vegetal model of Tuberosum Solanum (TS). METHODS: We tested the PFA clamp at different voltages (1400 V, 2000 V, 2800 V) and numbers of applications (2 or 4) on slabs of TS having different thicknesses (10 mm, 20 mm, 30 mm). Each slab was sliced transversally and the halves put together or kept whole. Every possible combination was tested twice. After 72 hours, we observed the resulting necrotic tissue and calculated its volume. We assessed the determinants of %volume of necrotic tissue, defined as observed volume relative to the ideal volume of necrotic tissue. RESULTS: A transmural lesion was noted in 68 (94%) of 72 specimens. Using 4 applications, there was a strong linear relationship between voltage and %volume regardless of specimen thickness (R2 = 0.94, R2 = 0.96, R2 = 0.97, all P < .001) but not when using 2 applications (R2 = 0.37, R2 = 0.87, R2 = 0.69 for 10 mm, 20 mm, and 30 mm, respectively, all P < .05). The voltages at which 100% volume was observed using 4 applications-corresponding to the curve intersections-are 958 V, 928 V, and 1044 V for the 10 mm, 20 mm, and 30 mm specimens, respectively. CONCLUSIONS: The epicardial PFA clamp reliably produced transmural lesions in a vegetal model of TS using 2 or 4 applications. With 4 applications, lesion volume demonstrated a predictable, linear relationship with increasing voltage, supporting the device's potential for controlled and consistent ablation.