An electrocardiogram (EKG/ECG) is a test that uses electrodes placed on the chest to detect and record the electrical activity of the heart. The EKG can show the heart's chambers, the pacemaker that initiates heartbeats, and the depolarization wave that causes the heart muscles to contract by removing the normal electrical distribution of cells before they recover to their resting state.

2.  Electrocardiogram
(EKG) is the test of heart
that shows the electric activity of it .
 It’s performed by putting electrodes on the
chest to detect the activity .
 The voltage pulse can be recorded by an
instrument called Electrocardiograph (ECG).
 To
understand what does EKG tell as , we
should know the basics of Heart Electrical
Activity .

3. •The heart is consisted of four champers (two
atria and two ventricles) .
•The right atrium contains specialized cells
called Sinoatrial node or ‘pace maker’ which
initiates the heart beat .

4. • The first beat – generated by SA node –
spreads through right and left atria and
causes them to contract .

5.  The
pulse that passes through muscle cells is
called Depolarization Wave .
 Depolarization
removes the normal electrical
distribution of each cell .
 When this wave passes the cell it recovers
the resting-state ‘ + out , - in ’