ECG

1. 
BASIC ECG
BY
SITI NURQAMAR BINTI HAMZAH
SN 1
CATHLAB DEPARTMENT

2. 
WHAt is ecg
 An electrocardiogram
(ECG ) is a quick test to
check the heartbeat. It
records the electrical
signals in the heart. Test
results can help diagnose
heart attacks and
irregular heartbeats,
called arrhythmias.
 Non –invasive , quick and
painless

3. 
 An ECG is done to check the heartbeat. It shows how fast or how slow
the heart is beating. ECG test results can help your care team diagnose:
 Irregular heartbeats, called arrhythmias.
 A previous heart attack.
 The cause of chest pain. For example, it may show signs of blocked
or narrowed heart arteries.
 An ECG also may be done to learn how well a pacemaker and heart
disease treatments are working.
 You may need an ECG if you have:
 Chest pain.
 Dizziness or confusion.
 Pounding, skipping or fluttering heartbeat.
 Fast pulse.
 Shortness of breath.
 Weakness or fatigue.
 Reduced ability to exercise.
Why’s is done

4. 
Anatomy of heart

5. 
What is the heart?

6. 
THE ELECTRICAL
CONDUCTION SYSTEM

7. 
The Electrical
conduction system
P wave :- atrial depolarization
QRS complex :- ventricular
depolarization
T wave :- ventricular
repolarization
Where is atrial depolarization?
In QRS complex

8. 
Proper 12-Lead ECG
Placement
ELECTRODE PLACEMENT
V1 4th Intercostal space to the right of the sternum
V2 4th Intercostal space to the left of the sternum
V3 Midway between V2 and V4
V4 5th Intercostal space at the midclavicular line
V5 Anterior axillary line at the same level as V4
V6 Midaxillary line at the same level as V4 and V5
RL Anywhere above the right ankle and below the torso
RA Anywhere between the right shoulder and the wrist
LL Anywhere above the left ankle and below the torso
LA Anywhere between the left shoulder and the wrist

10. 
 How to read and interpret electrocardiograms (ECG) is an important
skill to have.
 The main components of an EKG wave include the following:
 P wave
 PR segment
 QRS complex
 ST segment
 T wave
 U wave
 TP segment
 There are also intervals that will be discussed:
 PR interval
 QT interval
ECG WAVEFORMS

13. 
The Prototypical ECG
Tracing
 The P wave corresponds to electrical
impulse traveling through the atria.
 This is synonymous with atrial
depolarization and usually corresponds
with atrial contraction.
 The QRS complex corresponds to the
depolarization of the left and right
ventricles.
 It generally corresponds to the contraction
of the ventricles.
 The T wave corresponds to a repolarization
of the ventricles.

15. PR interval
• Is the time from the beginning of the P
wave to the first ventricular deflection.
(QRS complex)
• Represents the activity from the
beginning of atrial depolarization to the
beginning of ventricular depolarization.
• Normal PR interval (adult): 0.12-0.20s

16. QRS complex
• Represents the ventricular Depolarization or
electrical activity in the ventricles.
• Location: Follow the PR interval
• Measured from the beginning of Q wave to the
end of S wave
• Amplitude: Alters, depends on the position in
the 12 lead ECG.
• Duration:0.06-0.10s

17. ST Segment
• Represents a plateau between the end of
ventricular depolarization (QRS complex) and the
beginning of ventricular repolarization
• Normal ST segment is in line with the isoelectric line
• ST segment depression of 1-2 mm or more below the
baseline may indicate MYOCARDIAL ISCHAEMIA
• ST segment elevation 1-2 mm or more above the
baseline may indicate MYOCARDIAL INJURY

18. T Wave
• Represents the repolarization of the
ventricles.
• Location:Follow the S wave
• Polarity:- Same as preceding QRS
• Configuration:Typically rounded and
slightly asymmetrical (first upward part
ascending more slowly than the second
downward part)

19. QT Interval
• Represents ventricular depolarization
and ventricular repolarization
• Location:Extends from the beginning of
the QRS complex to the end of the T
wave.
• Duration:Between 0.36-0.44 sec (9-11)
small squares

20. 
COMMON ECG
FOUND

22. 
 Regular with normal P, Q-R-S
 T deflections and intervals.
 Rate = 60-100 at rest.
Sinus Rhythm

23. 
 Rate less than 60 per minute in an adult
Sinus Bradycardia

24. 
 Rate greater than 100 per minute in an adult. Note
that the p waves are still present.
Sinus Tachycardia

25. 
 Prolonged PR interval > 0.20 seconds due to a delay
in transmission from the atria to the ventricles.
First Degree Heart
Block

26. 
 A 2nd degree AV block is usually classified as
Mobitz Type I (Wenckebach) or Mobitz Type II.
 A Mobitz Type I heart block is characterized by
progressive lengthening of the PR interval until a
QRS complex is dropped.
2nd Degree heart block

28. 
Symptoms Second- and third-
degree heart block
 The second type of second-degree heart block — Mobitz 2 — is more serious and can lead
to:
 chest pain
 shortness of breath
 fainting
 nausea
 excessive fatigue
 heart palpitations
 Third-degree heart block stops the electrical signal altogether. This makes the heartbeat
irregular and unreliable, which can lead to serious health problems. Symptoms can include:
 fainting
 chest pain
 shortness of breath
 extreme tiredness
 The symptoms of third-degree heart block can be life threatening and people should seek
emergency medical help.

29. 
3rd Degree heart block
 A 3rd degree heart block (sometimes called a
complete heart block)
 A rhythm in which there is no relationship between
the P and QRS waves.
 The P to P intervals are regular but have no
relationship to the QRS complexes on the ECG.

31. 
Supraventricular tachycardia
(SVT)
 Extremely fast atrial rhythm with narrow QRS complexes when the impulse
originates above the bundle branches (above the ventricles).
 The main symptom of supraventricular tachycardia (SVT) is a very fast heartbeat
that may last for a few minutes to a few days. The heart beats 100 or more times a
minute. Usually during SVT, the heart beats 150 to 220 times a minute. The fast
heartbeat may come and go suddenly.
 Symptoms of supraventricular tachycardia may include:
 Pounding or fluttering feelings in the chest, called palpitations.
 A pounding sensation in the neck.
 Chest pain.
 Fainting or almost fainting.
 Lightheadedness or dizziness.
 Shortness of breath.
 Sweating.
 Weakness or extreme tiredness.

33. 
Atrial Fibrillation
 Very common arrhythmia.
 This rhythm is characterized by no visible P waves
and an irregularly irregular QRS complex.

34. 
 Supraventricular arrhythmia that is characterized by
a “saw-toothed” flutter appearance on the ECG that
represents multiple P waves for each QRS complex.
Atrial flutter

35. 
Premature Ventricular
Contractions
 Atrial rhythm is regular
 Ventricular rhythm is irregular
 QRS complex premature, usually followed by a
complete compensatory pause
 QRS complex is also wide and distorted, usually
>0.14 second.
 Premature QRS complexes occurring singly, in pairs,
or three

37. 
 Characterized by bizarre widened QRS complexes,
no P waves and usually a Rate over 100 per minute.
 May quickly degenerate to Ventricular fibrillation
and death. VT may be responsive to electrical
defibrillation.
Ventricular tachycardia

38. 
 Characterized by a chaotic wave pattern
 No pulse.
 VF may be responsive to electrical defibrillation.
Ventricular fibrillation

39. 
Asystole
 Commonly known as a “flat line”
 No electrical activity seen on the cardiac monitor.
 Not responsive to electrical defibrillation.

40. 
CONCLUSION
 ECG results can help
diagnose an unusually
fast heart rate, called
tachycardia, or an
unusually slow heart
rate, called bradycardia.
Heart rhythm. The heart's
rhythm is the time
between each heartbeat.
It's also the signal pattern
between each beat.