ECG Graph

Question 1

what does the P wave show?

Answer 1

atrial depol

Question 2

what does the QRS complex show?

Answer 2

ventricular depol

Question 3

what does the T wave show?

Answer 3

ventricular repol

Question 4

why is atrial repol not seen on an ECG?

Answer 4

masked by ventricular depol

Question 5

what creates the PR interval?

Answer 5

AV node delay

Question 6

what creates the ST segment?

Answer 6

ventricular systole

Question 7

what creates the TP interval?

Answer 7

diastole

Question 8

which lead is used as the rhythm strip?

Answer 8

lead II

Question 9

length and height for P wave?

Answer 9

<3mm

<2.5mm for height

Question 10

length for QRS?

Answer 10

3 small squares

Question 11

length for PR interval?

Answer 11

3-5 small squares

Question 12

how to work out heart rate?

Answer 12

300/large squares between beats OR large squares between R-R interval

Question 13

label

Answer 13

Question 14

positions of V1-V6?

Answer 14

V1 - 4th ICS left sternal edge

V2 - 4th ICS right sternal edge

V3 - between 2 and 4

V4 - 5th ICS mid clav line

V5 - anterior axillary line, same level as V4

V6 - mid axillary line, same level as V4

Question 15

how to calculate rate?in tachycardia?

Answer 15

300/large squares between R complexes

1500/small squares between R complexes

Question 16

how to calculate rate in irregular rhythms?

Answer 16

number of QRS complexes in 30 large squares x10

Question 17

to determine the cardiac axis, what leads are examined?

Answer 17

I

aVF

Question 18

in normal axis, what are lead 1 and aVF?

Answer 18

positive

positive

Question 19

in left axis deviation , what are lead 1 and aVF?

Answer 19

aVF - negative

lead I - positive

Question 20

in right axis deviation , what are lead 1 and aVF?

Answer 20

lead I - negative

aVF - positive

Question 21

what would mean there was an indeterminate axis?

Answer 21

negative

negative

Question 22

how long is a

small box

large box

5 large boxes?

Answer 22

0. 04
1. 2

1 second

Question 23

what lead can P waves be inverted in, and it is still normal?

Answer 23

aVR

Question 24

what is an R wave?

Answer 24

first upward deflection, even if not followed by a Q

Question 25

what pattern should R waves follow?

Answer 25

increase in amplitude from V1-6

Question 26

what is the rule for T waves?

Answer 26

should not be more than half the size of the preceding QRS

Question 27

how to calculate the length of QT interval?

Answer 27

square root of (R-R interval in seconds/QT interval in ms)