Source:http://linkedlifedata.com/resource/umls/id/C0018796
MSH: An impulse-conducting system composed of modified cardiac muscle, having the power of spontaneous rhythmicity and conduction more highly developed than the rest of the heart.,CSP: impulse conducting system composed of modified cardiac muscle and having the power of spontaneous rhythmicity and conduction more highly developed than the rest of the heart.,FMA: Conducting tissue of heart which consists of specialized cardiac myocyte in the myocardium.