Basic ECG Quiz

Question 1

ECG

Answer 1

measures depolarization, repolarizations
slight potential differences are measured on body surfaces (1mV)
depends on myocardium mass

Question 2

12 lead ECG

Answer 2

3 standard leads (I,II,III)
3 augmented leads (aVR, aVL, aVF)
6 precordial leads (V1-V6)

Question 3

What does an ECG detect?

Answer 3

arrhythmias
ischemia
damage
cardiac hypertrophy

Question 4

Which lead commonly has the largest magnitude QRS complex and why?

Answer 4

Lead II

heart sits and depolarizes at an angle

Question 5

Lead I

Answer 5

0 degrees

Question 6

Lead II

Answer 6

60 degrees

Question 7

Lead III

Answer 7

120 degrees

Question 8

aVR

Answer 8

positive on R arm

-150 degrees

Question 9

aVL

Answer 9

positive on L arm

-30 degrees

Question 10

aVF

Answer 10

positive on left leg

90 degrees

Question 11

precordial leads

Answer 11

placed on chest wall around heart
electrode is the center of the heart
gives more of a transverse (horizontal) view

Question 12

p wave

Answer 12

atrial depolarization

Question 13

QRS complex

Answer 13

ventricular depolarization

Question 14

t wave

Answer 14

ventricular repolarization

Question 15

5 large boxes= ____ seconds

Answer 15

1

Question 16

1 large box= ___ seconds

Answer 16

.2 seconds

Question 17

1 large box= ____ mV

Answer 17

0.5mV

Question 18

normal QRS duration

Answer 18

<3 small boxes

Question 19

normal p-r interval

Answer 19

< 1 big box

Question 20

r-r interval gives HR

Answer 20

300/# big boxes

Question 21

1 small box= __ seconds

Answer 21

.04 seconds