Explanation

ECG or Electrocardiograph is a graphic record of the electric current produced by the excitation of the cardiac muscles, for disease diagnosis. This is composed of P-wave, a QRS complex and a T-wave.The QRS comlex has 3 separate Q, R and S waves. P-wave_________ Depolarization of atria, produced by the activation of SA node. QRS complex_______ Depolarization of ventricles. PQ ___________ Impulse travel through atria, AV-node and rest of the conducting tissues. RS _________ Spread of excitation from AV-node to Purkinje fibres. T-wave ______ Repolarization of ventricles or ventricular relaxation (diastole).