In vivopulsed-field ablation in healthy vs. chronically infarcted ventricular myocardium: biophysical and histologic characterization

Figures

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  Figure 1. Gross pathology of focal (A) and linear (B) PFA. Linear lesion sets made in the anteroseptal LV endocardium (eight PFA applications, 4 cm long) and inferolateral LV endocardium (16 PFA applications, 5.2 cm long) had no visual gaps. LV, left ventricular; PFA, pulsed-field ablation.

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  Figure 2. Pulsed-field ablation of surviving myocytes within chronic subendocardial MI scar. The most apical PFA applications of scar BZ are demonstrated on gross pathology (A), electroanatomic mapping (B), sub-gross pathology with haematoxylin and eosin (C) and trichrome (D), and magnified histology demonstrating contraction band necrosis with oedema of surviving myocytes within scar (E and F). BZ, border zone; MI, myocardial infarction; PFA, pulsed-field ablation.

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  Figure 3. Pulsed-field ablation extends beyond chronic MI scar to its epicardial border. Pulsed-field ablation application at scar BZ is demonstrated on gross pathology (A), electroanatomic mapping (B), sub-gross pathology with haematoxylin and eosin (C) and trichrome (D), and magnified histology demonstrating contraction band necrosis and myocytolysis extending beyond the scar to its epicardial border (E). BZ, border zone; MI, myocardial infarction.

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  Figure 4. Cellular effects of PFA. Coagulative necrosis (left) was noted much more frequently with thermal ablation than with PFA. Contraction band necrosis and myocytolysis were not noted in chronic MI that was not ablated. PFA, pulsed-field ablation.