1. ECG BASICS
SPEAKER: Dr M Rama Bhupal Reddy
MD (Anaesthesia)
DrNB (CCM)

2. ECG/EKG
• It is the procedure of recording the electrical
activity of the heart
• Electrocardiograph is the machine
• Electrocardiogram is the record

3. • The ECG is not only
the oldest but, in
fact, over 100
years after its
introduction,
continues as the
most commonly
used
cardiovascular
laboratory
procedure.

5. Cardiac
Conduction
System
Purkinje
fibers
1
2
3
4
5
4

6. Standard 12-Lead EKG
• Six limb leads
–Leads I, II, III, aVR, aVL, aVF
• Six chest leads (precordial leads)
–V1, V2, V3, V4, V5, V6
• Information from 12 leads obtained from
the attachment of only 10 electrodes.

7. Precordial Chest Leads
For every person, each precordial lead placed in the
same relative position
V1 - 4th intercostal space, R of sternum
V2 - 4th intercostal space, L of sternum
V4 - 5th intercostal space, midclavicular
V3 - between V2 and V4, on 5th rib
V5 - 5th intercostal space, anterior axillary line
V6 - 5th intercostal space, mid-axillary line

8. • Precordial
leads
2nd ICS
1st ICS
3rd ICS

9. View The Leads Provide
• II, III, aVF – view inferior wall of heart
• V1 and V2 – view septal wall of heart
• V3 and V4 – view anterior wall of heart
• I, aVL, V5, V6 – view lateral wall of heart

10. Lateral View – I, aVL, V5, V6
I
aVL
V5
V6

11. Inferior View – II, III, aVF
II
III aVF

12. Septal View – V1 & V2
V1
V2

13. Anterior View – V3 & V4
V4
V3

14. Basic 12-Lead EKG Format
Lead I
Lateral wall
aVR
not evaluated
V1
Septum
V4
Anterior wall
Lead II
Inferior wall
aVL
Lateral wall
V2
Septum
V5
Lateral wall
Lead III
Inferior wall
aVF
Inferior wall
V3
Anterior
V6
Lateral wall

15. Waves
P
Q
R
S
T

18. Electrocardiogram waves
• P-wave – depolarization of atria
– Atria begin contracting about 25msec after the start of the
p-wave
• QRS-complex – ventricular depolarization
– Ventricles begin contracting shortly after the peak of the R
wave
• T-wave – ventricular repolarization

19. ECG Interpretation
1) Rate
2) Rhythm
3) Axis
4) P wave
5) PR Interval
6) QRS Complex
7) ST Segment and T wave

23. SINUS RHYTHM

24. RHYTHM

42. Ventricular Tachycardia

43. Ventricular Fibrillation

44. Torsade De Pointes