Basic ECG Knowledge

Question 1

What does R-R interval represent

Answer 1

Time between ventricular depolarizations

Question 2

QRS width

Answer 2

less than .12
> .12 = wide qrs

Question 3

QT interval duration

Answer 3

generally half the R-R

Question 4

What makes a Q wave pathological

Answer 4

> 2mm deep, longer than 1 small box

Question 5

PR interval

Answer 5

0.12-.2 seconds (3-5 small boxes)

Question 6

Sokolow-Lyon Criteria

Answer 6

• used for LVH
• S wave depth in V1 + tallest R wave in V5 or V6 = > 35mm

Question 7

What is Lewis Criteria used for

Answer 7

RVH
(R in I + S in III) - (S in I + R in III) = <15