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Year 3 - CR > Interpretation of ECG > Flashcards

Flashcards in Interpretation of ECG Deck (87)
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1

Name the parts that make up the ECG

- P wave
- QRS
- T wave

2

What does the P wave signal

atrial depolarisation

3

What does the QRS complex signal

- ventricle depolarisation

4

What does the T wave signal

- Ventricular repolarisation

5

What should the first thing in an ECG should you look at

- to make sure you are looking at the right person ECG - check the name, date of birth and hospital number
- its calibration - 1mV = 10mm

6

What are the two calibration numbers that you should remember

- Paper speed should be 25mm/sec
- calibration should be 1mV = 10mm

- these are at the bottom of most ECG

7

What should the paper speed in an ECG be

25mm/sec

8

Where should the chest leads go

6 of them
- V1 - 4th intercostal space on the right sternum
- V2 - 4th intercostal space on the left sternum
- V4 - 5th intercostal space midclavicular line (apex beat)
- V3 between V4 and V2
- V6 - mid axillary line

9

what does the chest lead allow you to do

- Look at the QRS complex from different planes

10

describe how the QRS becomes positive

- It becomes positive by the time you reach V4

11

name the 6 limb leads

I
II
III
aVR
aVF
aVL

12

Out of the limb leads which should be positive and negative

I - QRS is meant to be positive
II - QRS is meant to be positive
III- QRS is meant to be positive
aVR - should always be negative
aVF - QRS is meant to be positive
aVL - halfway between the right direction so half and half

13

when is QRS positive

QRS is positive when ventricular depolarisation is in the right direction

14

Name the chest leads

V1-V6

15

Name the normal ECG wave forms and what is normal

- PR = 120-200 msec (3-5 small Sq)
- QRS < 120 msec (< 3 small Sq)
- QTc < 440 msec

16

what does 1 small sequence and 1 big sequence in msec

1 small Sq = 40 msec
1 big square= 200 msec

17

How do you work out the QTc

QT/ square root of RR

18

what is the QTc dependant on

- it is dependant on the heart rate

19

How do you read an ECG

– Rhythm
– Rate
– Axis
– P waves
– PR interval/ heart block
– QRS morphology/ ST segments/ T waves
– QT interval

20

How do you assess Rhythm

- are the QRS regular complexes
- is there a P wave before every QRS

21

What is the definition of sinus rhythm

- there is a P wave before every QRS
- requires an ECG to know

22

What is sinus arrhythmia

- variation of RR interval with respiration
- normal variant

23

Why is lead II used to look at the P wave and thus used in rhythm

one of the best leads to look at the p wave
- atrial depolarisation is in the same direction

24

What are ectopics

When you heart throws up some extra beats
- ectopics above the AV node are called supraventricular ectopics
- ectopics below the AV node are called ventricular ectopics

25

What is the difference between supra-ventricular and ventricular ectopics

Supraventricular
- ectopics above the AV node are called supraventricular ectopics
- narrow QRS complex

Ventricular
- ectopics below the AV node are called ventricular ectopics
- Broad QRS complex

26

What is the normal heart rate

50-100bpm

27

How do you calculate heart rate

- look at the RR interval
- count the number of squares between the QRS complex
- number of big squares and then divide 300 by the number of big squares

28

who can you not calculate heart rate in

- Patients who have an irregular heart rhythm

29

What is the axis

Axis is the net electrical vector of the heart
- gives an overall idea of the direction of depolarisation

30

in what direction does the heart depolarise

- from the top of the right shoulder and down
- from aVR to II