The Normal ECG

Question 1

What is the amplitude of QRS complex?

Answer 1

• Q wave < 0.2 mv
• R wave = 0.6-1.2 mv
• S wave < 0.6 mv

Question 2

What does QRS complex indicate to?

Answer 2

Indicates ventricular

depolarization

Question 3

What does T wave indicate to?

Answer 3

Indicates ventricular repolarization.

Question 4

What is the duration of QRS complex?

Answer 4

about 0.06-0.11 sec

Question 5

What is the duration of T wave?

Answer 5

about 0.25 sec

Question 6

What is the amplitude of T wave?

Answer 6

0.4mv

Question 7

What is the duration of PR interval?

Answer 7

0.12-0.2 s

Question 8

How is PR interval measured?

Answer 8

Is measured from the beginning of P wave to the beginning of QRS complex

Question 9

How does PR interval vary with heart rate?

Answer 9

PR interval varies inversely with the heart rate.

Question 10

PR interval conductivity measures the conductivity in the __________

Answer 10

AV node

Question 11

How is heart rate of the ECG calculated?

Answer 11

Heart rate from an ECG =
Speed of the paper from the machine (in minutes)/
Duration of one ECG cycle (in millimeters)

Question 12

Where does the cardiac axis lie on?

Answer 12

•Lies normally between the angles -30

& +90 degrees (or up to + 110).

Question 13

Left axis deviation is caused by ________

Answer 13

left ventricular hypertrophy

Question 14

Right axis deviation is caused by________

Answer 14

right ventricular hypertrophy

Question 15

Einthoven’s triangle is formed by ________

Answer 15

Bipolar leads

Question 16

Einthoven’s triangle is used to_________

Answer 16

determine the

cardiac axis

Question 17

What does P wave indicate to?

Answer 17

atrial depolarization

Question 18

What is the duration of P wave?

Answer 18

about 0.1 sec

Question 19

What is the amplitude to P wave?

Answer 19

about 0.2 mv (<0.3 mv)