Physiology (electrocardiography ecg)

1. Physiology practical 2
(Electrocardiography - ECG)
By : Osama Al-Zahrani
@OSAMA_Z96

2. ECG Waves

3. Electrocardiogram
• ECG is a record of the changing potentials of the electrical field
imparted by the heart.
• It is a clinical test used as an indicator of cardiac function.
• Also ECG used for detecting cardiac arrhythmias and assessment of
the myocardium.
• The routine ECG include 12 leads.
• 6 Chest leads, And 6 Limb leads (3bipolar and 3unipolar)

4. Electrocardiogram
Limb leads
Chest leads
The ECG
apparatus
The GEL used to increase the conductivity

6. Calculation of heart rate
• We can calculate the heart rate from the ECG by numbering the big
squares in the chart then divide 300 on this square number :
• 300 / Squares = Heart rate
• For example :
Calculate the heart rate :
300 / 5 = 60 bpm
1 2 3 4 5

7. The Victim! 