Fig. 5
From: Myofiber organization in the failing systemic right ventricle
The apical whorl of the systemic RV is replaced by an incomplete whorl or even a chaotic net of fibers (Supp video 8). a –MA/AA heart showing absence of an organized apical whorl with disorganized, crossing fibers. b – DIRV heart has a more organized apex with a 2-part whorl and ingression of fibers to form longitudinal muscle bundles (blue). c – An inverted apex in C-TGA heart with a well-organized LV apical whorl (right-sided) and a smaller and incomplete RV whorl (left-sided). d – Apex of the hypertrophied structurally normal heart (RVH ‘normal’) showing a large, organized RV apical whorl and a smaller LV whorl where epicardial fibers take a curved course around the apex and ingress superiorly and inferiorly to form longitudinal endocardial fibers on the septum and free wall, respectively