ECG

Question 1

ECG revision

What is the cardiac conduction?

Answer 1

Question 2

ECG Revision

What is an ECG?

Answer 2

Leads 1,2,3 (verticle frontal plane)
Limb Leads (calculated) AvR, AvF, AvL (verticle frontal plane)

Chest Leads- aroud the chest-horizontal like transverse plane
V1,2= RV and anterior
V3,4 Septal
V4-6=lateral

Lead 1 = 0’
Lead 2 = 60’
aVF=90’ (calculated)
Lead 3= 120’
aVR= -150’
aVL=-30

Question 3

ECG Revision

Systematic Approach to reviewing an ECG

Answer 3

• Rate
• Rhythm
• Axis
• P wave
• PR interval
• QRS complex
• ST segment
• T waves
• QT interval

Make note of the paper speed= should be 25mm/sec

Question 4

ECG Revision

Rate

Answer 4

• Ensure speed is 25mm/sec
• Each large square is 5mm
• 5 squares is 1 second
• 300/ large squares= bpm (ONLY GOOD IF REGULAR)

Usually ECG is 10seconds long so… complexes * 6 = bpm

Bradycardia < 60
Tachycardia > 100

Question 5

ECG Revision

Rhythm

Answer 5

What are the P waves doing?
Rhythm strip is usually lead 2.

This is done by measuring the distance between one P wave and the next P wave or from one R wave to the next.

If the PP or RR intervals are consistent then the rhythm is normal or regular.