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)
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
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