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