The ECG Flashcards
1
Q
How does an ECG work?
A
Potential differences between distant sites on the Body surface measurable by electrodes placed on the skin coupled to a sensitive recording device (ECG)
2
Q
What are the 3 standard limb leads?
A
Lead 1 : Right arm (RA) -ve to Left arm (LA)+ve
Lead 2: RA-ve - LL+ve
Lead 3 : LA-ve - LL+ve
3
Q
What are the 3 augmented limb leads?
A
- augmented voltage right
- augmented voltage left
- augmented voltage foot
4
Q
How many chest leads are there ?
A
6
5
Q
How do you calculate heart rate?
A
300/number of large squares between beats
6
Q
What is the ECG Rhythm strip?
A
-prolonged recording of one lead (usually standard limb lead 2) - this allows you to detect rhythm disturbance
7
Q
Where is the rhythm strip on the paper?
A
Bottom of the page
8
Q
Why are 12 leads needed?
A
- Determine the axis of the heart in thorax
- Look for any ST segment or T wave changes in relation to specific regions of the heart. This is curtail e.g. in diagnosing Ischaemic Heart Disease
- Look for any voltage criteria changes. This is curtail e.g. in diagnosing chamber hypertrophy
9
Q
What 3 significant disease cannot be identified by a resting ECG?
A
- myocardial infarction
- intermittent rhythm disturbance
- stable angina
