1. المحتوى غير شامل لكل ما تحتويه المحاضرات
E.C.G
References:
- Doctor’s lecture
- First Aid EM clerkship
- ECG Intepretation made incredibly easy (5th edition)
- Some YouTube videos
- My notes
المحتوى غير شامل لكل ما تحتويه المحاضرات

2. Amplitude= voltage
Amplitude
Time

3. 1 small box = 0. 04 Sec = 0. 1 mV or 1 mm 1 big box= 0. 2 Sec= 0
1 small box = 0.04 Sec = 0.1 mV or 1 mm 1 big box= 0.2 Sec= 0.5 mV= 5 mm 5 big boxes = 1 Sec 2 large boxes= 1 mV

5. 1) P wave= Atrial depolarization
Amplitude: 2 to 3 small boxes
Duration: less than 1 big box
2) PR interval= Atrial impulse from atria to AV node
Duration: 3 small boxes to 1 big box ( 0.12 to 0.2 Sec)
- Prolonged interval (>0.2 sec) may indicate heart block

6. 3) QRS complex= ventricular depolarization
Amplitude: 5 to 30 mm (remember 1 small box=1mm)
Duration: 0.06 to 0.10 Sec
A prolonged QRS complex may indicate Ventricular tachycardia and Bundle Branch Block (BBB)
Left BBB
- Right BBB
4) ST segment: usually isoelectric (flat)
A change in the segment may indicate myocardial damage
It may become elevated or depressed

7. Elevated ST segment
1) Acute MI 2) Pericarditis 3) Early repolarization pattern in the young

8. Depressed st segment 1) Unstable angina
2) Left ventricular strain pattern

9. 5) T wave= ventricular repolarization
Amplitude: 0.5 mm (remember 1 small box=1mm)
Peaked/tented T wave indicate hyperkalemia, Subendocardial ischemia
- Inverted T wave indicate LV Strain pattern Dynamic t-wave changes of ischemia
6) U wave: Not always show but when it’s there It may indicate hypocalcemia or hypokalemia

10. P waves before every QRS complex
Sinus Rhythm
P waves before every QRS complex
Types of sinus rhythm:
1) Normal sinus rhythm (NRS)
2) Sinus tachycardia
3) Sinus bradycardia
4) Sinus arrhythmia

11. NSR

12. Sinus tachycardia

13. Sinus braycardia

14. Axis Normal Axis: ( -30 to +90) Right axis deviation: (+90 to 180)
Left axis deviation: (-30 to -90)

15. Important POINTS
A positive degree designation doesn't mean that the pole is positive – you have to check the leads-
A wave pointing upward considered positive
A wave pointing downward considered negative
Infants and children normally have right axis deviation
Pregnant women normally have left axis deviation

16. Axis significant
Once you determine whether the axis is normal or deviated you can guess the cause
For example the left axis deviation indicate these conditions:
Wolff Parkinson white syndrome
Inferior wall myocardial infarction
Left ventricular hypertrophy
So when you see left axis deviation on ECG you’ll think of these
* This is just some of the causes not all of them

17. Quadrant method
Observe the QRS complexes in lead ( l + aVF)

18. Observe the QRS complexes in lead ( l + aVF)
Right axis deviation
Observe the QRS complexes in lead ( l + aVF)

19. Left axis deviation Positive in lead l Negative in lead aVF and ll
Observe the QRS complexes in lead ( l + aVF)

20. Now let’s start

21. 1) dETERMINE THE RHYTHM
Paper and pen method (Variation up to 0.04-one small box is normal)

22. 2) Determine the rate 1) Regular= 300 / Number of big boxes between RR
2) Irregular= Number of QRS complex X 6  in 10 sec paper
X 10  in 6 sec paper
X 2  in 30 sec paper
Remember:
5 big boxes= 1 sec
Normal HR= 60 to 100 bpm

23. 3) Evaluate p wave Is it present?
Do all the waves have the same configuration?
Do all have same size and shape?
Is there p wave for every QRS complex?

24. 4) Determine the duration of pr interval
small square between the start of p wave and the start of QRS complex X 0.04 (since each small box=0.04)
Now
Is the duration in the normal range? 0.12 to 0.2? (3 to 5 small boxes) remember: 5 small boxes=1 big box
Duration > 1 big box = 1st degree HB
Duration < 3 small boxes=
1- Pre-excitation syndromes
WPW Syndrome
LGL Syndrome
2- Junctional rhythm

25. 5) Determine the duration of QRS complex
Is the duration in the normal range? 0.06 to 0.10 sec?
Are all the complexes the same size and shape?
Does a QRS complex appear after every p wave?

26. 6) Evaluate t waves Are T waves present?
Do they all have a normal shape?
Do they all have a normal amplitude?
Do they all have the same amplitude?

27. 7) Determine the duration of the qt interval
- Is the duration in the normal range? 0.36 to 0.4 Sec?

28. 8) Evaluate any abnormality
- Check ST segment for abnormalities - Check U wave presence

29. Abnormalities

30. Ventricular abnormalities
Atrial abnormalities
Atrial fibrillation
Atrial flutter
Supraventricular tachycardia
Multifocal tachycardia
Ventricular abnormalities
Ventricular tachycardia
Ventricular fibrillation

31. Atrial fibrillation Characteristic: No P wave Irregular Narrow complex
Tachycardia
Management:
A) Stable: chemicals (beyond EMR level)
B) Unstable: cardioversion

34. Atrial flutter Characteristic: Saw tooth Irregular Narrow complex
* Narrow complex= less than 3 small boxes

37. Multifocal tachycardia
Different shape of P wave
Irregular

38. Supraventricular tachycardia
Characteristic:
No P wave
Narrow complex
Regular
Management:
A) Stable:
1- vagal+valsalva maneuver
2- adenosine – B blockers - Ca++ channel blockers
B) Unstable: Cardioversion

40. Ventricular tachycardia
Characteristic:
Wide complex
Regular
Rapid
Management:
Pulse
B) No pulse: defibrillation
stable
Unstable= cardiovesion

42. Torsade de points If unstable => cardioversion
Refers to a ventricular tachycardia variation in which QRS axis swings from positive to a negative an a single lead
Treatment:
IV magnesium sulfate
If unstable => cardioversion

44. Ventricular fibrillation
Characteristic:
Wide complex
Irregular
Bizarre
Management:
Defibrillation
CPR

47. AV block
More than 0.2 PR interval
RR: regular or not
PR: fixed or not

48. ✔ ✗ Degree Regulation Consistency Treatment 1st degree
شكرًا، مع السلامة
2nd degree
Mobitz type l ✗
Mobitz type ll
- Admission
- pacemaker
3rd degree

49. 1st degree

50. 2nd MOBITZ type 1

51. 2nd mobitz type 2

52. 3rd

53. Anatomy of the conduction system
Understand this before moving on

54. Understand this before moving on

55. Left bundle branch block (LBBB)
The block occur before anterior and posterior fascicles split
Ischemia can be masked with LBBB. (use of sgarbossa criteria can be helpful)
ECG:
QRS duration > 0.12 sec
Large wide R waves in l, aVL, V5, V6
No Q waves in l, aVF, V5, V6
ST and T waves directed opposite to terminal 0.04-sec QRS

56. LBBB

57. Right bundle branch block (RBBB)
In some circumstances when the right bundle is non functional as in RBBB The right ventricle must receive the signal for depolarization from left ventricle Sense this signal is not transmitted along the same specialized conductive tissues Depolarization of the right ventricle is slow compared to the left This results in wide QRS complex

58. RBBB * Ischemia in not masked with RBBB ECG:
QRS duration > 0.12 sec
Triphasic QRS complexes (rabbit ears)
Regular sinus rhythm
Wide S wave in l, aVL, V5, V6
*Triphasic= it means the trend of the ECG signal deflect. If there are thee deflection (i.e two positive and one negative) it's called triphasic

59. Biphasic QRS complex
Triphasic QRS complex

60. RBBB

61. (اللهم انفعني بما علمتني وعلمني ما ينفعني وزدني علمًا)
انتهى
(اللهم انفعني بما علمتني وعلمني ما ينفعني وزدني علمًا)
وفقنا الله جميعًا