adjacent to adjacent to composed primarily of muscle cell projection endocardium myocardial layer myocardium trabecular layer UBERON:0004124 myocardial trabecular layer trabeculae heart muscle trabecula MA:0002866 The layer of the myocardium composed of projections of contractile myocytes. The trabecular layer is bounded internally by the endocardium. In zebrafish, unlike the trabeculations of higher vertebrates, both atrial and ventricular trabeculae have more strut-like character, and are more uniform without apparent regional differences[ZFA]. EFO:0003706 trabecula of heart muscle TAO:0005059 ZFA:0005059 trabecular layer