Fig. 4
Evaluation of LV wall thickness and local tissue characteristics after PFA using cMRI and histology. (a) 3D LGE cMR images 24 h post ablation, formatted along long-axis (a.i.) and short-axis (a.ii.) planes used to measure LV wall thickness at the site of each ablation. (b) Summary of cMRI-derived LV wall thickness at the site of PFA using differing dose schemes (T = pulse trains) at 24 h, 7 days, and 6 weeks after ablation. A linear mixed effects model controlling for individual differences and number of pulse trains revealed that wall thickness was significantly higher at 24 h post-ablation compared to subsequent time points (*p < 0.05, **p < 0.01, ***p < 0.001). (c) Formalin-fixed cross section of a heart of a pig sacrificed at 48-h time point and (d) corresponding 3D LGE cMRI showing two adjacent 48-h old PFA lesions (arrows), both created by delivering 1500 V in 8-pulse trains. Masson’s trichrome stained sections from a 48-h time point showing (e) hemorrhage (arrowheads), (f) minor interstitial leukocytic infiltrates (arrowheads), and (g) contraction band necrosis. Healthy myocardium at a remote site H) is within normal limits.
