1.1 ECG WAVES AND INTERVALS-What do they mean?

(1) P wave: sequential depolarization of the right and left atria

2) QRS complex: right and left ventricular depolarization

3)ST -T wave: ventricular repolarization

4) U wave: an electrical-mechanical event at beginning of diastole

5) PR interval: time interval from onset of atrial depolarization (P wave) to onselof ventricular muscle depolarization (QRS complex)

6) QRS duration: duration of ventricular muscle depolarization ( width of the QRS complex)

7) QT interval: duration of ventricular depolarization and repolarization

(8) PP interval: rate of atrial or sinus cycle

(9) RR interval: raté of ventricular cycle