myocardium http://upload.wikimedia.org/wikipedia/commons/6/6e/Glanzstreifen.jpg heart myocardium VHOG:0000083 TAO:0001319 XAO:0000065 EHDAA2:0004150 CALOHA:TS-0440 The middle layer of the heart, comprised mainly of striated cardiac muscle fibers. muscle of heart FMA:9462 BTO:0000901 EMAPA:32688 EV:0100022 GAID:173 OpenCyc:Mx4ro36AFrCvEduAAAAOpmP6tw MESH:D009206 MA:0000164 UBERON:0002349 EFO:0000819 cardiac muscle RETIRED_EHDAA2:0001220 galen:Myocardium NCIT:C12371 myocardial uberon heart muscle MAT:0000453 ZFA:0001319 Robust muscular tunic of the heart which forms the basic part of its walls. Its external surface is covered by the pericardium and its internal one by the endocardium. [Dorian_AF, Elsevier's_encyclopaedic_dictionary_of_medicine, Part_B:_Anatomy_(1988)_Amsterdam_etc.:_Elsevier][VHOG] The middle layer of the heart, consisting of cardiac muscle.[AAO] TODO - check 'Myocardum proper' in FMA. We superclass the more generic class for now. FMA has is_a muscle layer - should we add this? ZFA and BTO both have is_a 'cardiac muscle' (tissue?). But in U we also follow FMA and have cardiac muscle tissue of myocardium (there is also Fibrocollagenous connective tissue of myocardium), which would be identical (see issue-10). Note that GO also treats left/right ventricular cardiac muscle tissue synonymous with ventricular myocardium BSA:0000089 UMLS:C0027061 AAO:0010410 heart layer structure with developmental contribution from neural crest layer of muscle tissue