2.  Electrocardiogram
(EKG) is a test of heart
that shows the pattern of heart beat.
 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 ’ .

6.  After
the wave passes away from atria , it’ll
reach the ‘Atrioventricular node’ (AV) .
 AV node directs the pulse towards the
ventricles through Purkingi fibers .
 After
the wave passes , the ventricles relax
and SA node triggers the pulse again .

8. Elecrocardiograph

9. The adjacent figure shows the ECG for a
normal heart .
 P : just before the atria contracts .
 QRS : just before the ventricle contract .
 T : the ventricles begin to relax .
 The device detects the depolarization wave
not the contraction of muscles .

10.  QRS is wider than normal

Heart enlargement : one or more champers
are enlarged , or Hypertrophy leading to
muscle enlargement .

11. 
Tachycardia and bradycardia
Bradycardia 50 BPM
Tachycardia 100 BPM