4. ECG waves and what they mean

What do electrocardiograms measure?

They measure electrical activity, meaning they can measure myocytes polarizing and depolarizing, but cannot measure valves opening or pressure or contraction force

What does the P wave track?

Atrial depolarization, which is followed by atrial contraction and ventricular filling

What does the QRS complex track?

ventricular depolarization and atrial repolarization, which is followed by ventricular contractions and when the atria relaxes and when the AV valve closes

What does the T wave track?

ventricular repolarization, ventricular relaxation follows and semilunar valves close