Distention of the Immature Left Ventricle Triggers Development of Endocardial Fibroelastosis: An Animal Model of Endocardial Fibroelastosis Introducing Morphopathological Features of Evolving Fetal Hypoplastic Left Heart Syndrome

Figure 3

(a) A representative photograph and slides of the distended LV model. Each shows short axis views of the ventricles. The endocardium is covered by macroscopically discernible pearly white thick layers of fibroelastosis. Masson’s Trichrome- and Elastica van Gieson-stained slides depict thick fibrous layers with an abundant collagen deposition (stained in blue) and stratified elastin fibers (black wavy lines) on the endocardial surface. (b) Representative Hematoxylin and Eosin- and Masson’s Trichrome-stained slides in the unloaded LV model. The LV appears contracted with a thickened myocardial layer. No apparent fibrous tissue develops on the endocardium. (c) A case with a mural thrombus in the unloaded LV model. Masson’s Trichrome-stained slides depict a large mural thrombus occupying the LV cavity. The mural thrombus has an abundant collagen deposition but no elastin fibers in an Elastica van Gieson-stained slide. Black scale bar, 1 mm; white scale bar, 200 μm. (d) Comparison of EFE scores between the distended LV model and the unloaded LV model ().

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