Fig. 1From: Myofiber organization in the failing systemic right ventriclea Anterior CMR view of a normal right ventricle (RV) illustrating the convention we have used for helix angle as described in the Methods. First, the long axis (LA) of the ventricle was constructed as a line from the center of the tricuspid valve annulus (TV Ann) to the apex of the right ventricle (RV Apex). A short-axis plane (SA) was then constructed perpendicular to the long axis of the ventricle. The SA plane was considered 0°. Fibers running superiorly and toward the base were assigned a negative helix angle (−Θ) and those directed superiorly and toward the apex a positive helix angle (+Θ). LV – left ventricle; Septum – interventricular septum b Anterior oblique view of the MA/AA heart with a tractogram of the rightward-anterior wall of the RV shown. The red epicardial fibers (dashed arrow +Θ) are directed superiorly and toward the apex with a positive helix angle. In contrast, the blue endocardial fibers (dashed arrow –Θ) pass superiorly and toward the base with a negative helix angle. The green fibers at the acute margin (curved solid arrow 0°) are circumferential epicardial fibers. Color coding varies from sample to sample according to the scan direction and will be indicated in each figure showing glyphs and tractogramsBack to article page