General process of excitation and contraction of cardiac muscle Initiation of action potentials in sinoatrial node Conduction of action potentials along specialized conductive system Excitation-contraction coupling Muscle contractionGeneral process of excitation and contraction of cardiac muscle • Initiation of action potentials in sinoatrial node • Conduction of action potentials along specialized conductive system • Excitation-contraction coupling • Muscle contraction