Optional visualization images put out by the macro. Segmentation by concentric wall layers (A), laterolateral composition (B), or both combined (C). Crosshatching shows overlap of regions. Darker areas in (C) indicate right heart, medium areas septum, and light ones left heart. The sketches are representations of the section shown in Fig. 2B. Labeling of ventricles in sketches is done automatically by QuantSeg. False-color representation (D) highlighting collagen in the heart section shown in Fig. 2A. Rectangle represents zoomed inlay. Scale bar: 1000 μm. Abbreviations: LV: left ventricle, RV: right ventricle.