muscle cell cardiac muscle cell A myocyte located in the heart. The contractile fiber resembles those of skeletal muscle but are only one third as large in diameter, are richer in sarcoplasm, and contain centrally located instead of peripheral nuclei. SNOMEDCT:86441007 A striated muscle cell found in the heart. They develop from cardiac myoblasts. NCIt:C13002 A heart muscle cell. James Malone Tomasz Adamusiak NIFSTD:sao658938043 Striated muscle cells found in the heart. They are derived from cardiac myoblasts (myoblasts, cardiac (MSH).