Matching Pairs CVS Heart: Cells & ECGOnline version Pacemaker, Contractile cells & ECG by Dr MAHABOOB KHAN SULAIMAN 1 Non auto-rhythmic cells with long refractory period 2 Contractile cells 3 Auto-rhythmic 4 Ventricular depolarization 5 Atrial depolarization 6 Ventricular repolarization 7 Pacemaker Cells 8 Funny current 9 Plateau phase called pacemaker potential, Ca 'T' type channels open P wave QRS wave Contractile cells characteristic of contractile cells, slow Ca channels open T wave 1% of cells with no true resting potential 99% cells with true resting potential Pacemaker cells