constitutional_part_of Nodal myocyte Myocyte of sinuatrial node FMA:67102 Myocyte of sinoatrial node Nodal myocyte which consists of the pacemaker cell and the transitional myocyte of sinuatrial node. SA nodal myocyte Sinuatrial node myocyte fma Conducting system of interatrial septum Atrial septal branch of anterior internodal tract Atrial branch of anterior internodal tract Conducting system of heart Internodal tract Anterior internodal tract Middle internodal tract Posterior internodal tract