Electrocardiograms Flashcards
What do the axes in an ECG represent?
Voltage against time
What is the name of the normal rhythm?
Sinus rhythm
What do PQRST stand for?
P - atrial depolarisation
QRS - ventricle depolarisation
T -ventricle repolarisation
ECG tells us about the potential difference between the positive and negative electrode placed on the limbs. What don’t ECGs tell us?
Cardiac output
Blood oxygenation
If the line on the ECG is above the baseline, what does this tell us?
The action potential is moving towards the positive electrode
If the line on the ECG is below the baseline, what does this tell us?
The action potential is moving towards the negative electrode
The letter T can be positive or negative bcause the repolarisation of the ventricles is unorganised. True or false?
True
Why do we take ECGs on right lateral recumbency?
The heart is more central
What is the word for the pulse being too fast?
Tachycardia
What is the word for the pulse being too slow?
Bradychardia
Abnormal rhythms can be regularly irregular or irregular irregular. What are abnormal rhythms called?
Arrhythmia
What do augmented unipolar leads do? Why do we have 3 leads?
Compare one limb with the average of the other two.
The leads cross over in centre of heart, gives us as many angles of heart ECG as possible
What does an increased height show?
Increased potential difference
What does an increased width show?
Increased time for action potential to move through the heart
(May be larger chamber)
What does a change in direction of the ECG show? Give an example of what this could be and what this would cause
The AP is not following a normal pathway
Ectopic pacemaker, less effective CO