ABSTRACT
The electrocardiogram (ECG) is a recording of this surface electrical activity. An ECG provides information on: Heart rate and rhythm, the pattern of electrical activation of the atria and ventricles, the approximate mass of tissue being activated, damage to heart muscle and changes in heart muscle electrolyte composition. The ECG is the body surface recording of voltages that result from the moment-by-moment conduction of action potentials from myocyte to myocyte. ECG waves reflect the electrical forces produced by the sequential depolarization and repolarization of myocytes. An augmented unipolar limb lead is recorded with one limb connected to the positive electrical pole of the ECG machine. The connection to the negative pole of the ECG machine is created by connecting two other limbs through resistors. The ECG signal remains at the baseline as the wave of depolarization moves slowly through the Atrioventricular (A).
