Question

The given figure is the $ECG$ of a normal human. Which one of its components is correctly interpreted below?

• A. Complex $QRS$ - one complete pulse
• B. Peak $T$ - initiation of total cardiac contraction
• C. Peak $P$ and peak $R$ together - systolic and diastolic blood pressures
• D. Peak $P$- initiation of left atrial contraction only

Answer 1

Answer: (A)

Complex $QRS$ - one complete pulse

Answer 2

The $QRS$ complex represents the depolarisation of the ventricles, which initiates the ventricular contraction. By counting the number of $QRS$ complexes that occur in a given time period, one can determine the rate of heart beat of an individual.