part of part of contributes to morphology of cardiac atrium endocardium endocardium of atrium FMA:7284 atrium of heart endocardium ZFA:0001614 atrium endocardial tissue VHOG:0000606 atrium endocardium heart atrium endocardium atrial endocardium cardiac atrium endocardium EMAPA:32745 Endocardium that is part of the atrium. TAO:0002169 SCTID:192001005 Cardiac atria endocardium endocardium of cardiac atrium endocardium of Cardiac atria endocardium of heart atrium UBERON:0002166 endocardium of atrium of heart MA:0000077