ECG generation and interpretation

Question 1

What are cardiomyocytes

Answer 1

cardiac muscle cells

Question 2

What is responsible for rhythmic pumping of the heart

Answer 2

cardiomyocytes

Question 3

what is the resting potential of a cardiomyocyte

Answer 3

-90mV

Question 4

What keeps the cardiomyocyte negative

Answer 4

potassium ions leaving the cells

Question 5

Dipole

Answer 5

created by equal but opposite charges that are seprated by a short distance

Question 6

when is the deflection across cells greatest

Answer 6

when recording electrodes at the poles

Question 7

if both sides of the cell are the same charge what is the potential difference

Answer 7

0

Question 8

If one side of the cell is positive or negative and the other isn’t, will there be a potential difference

Answer 8

yes

Question 9

Where do you place the 3 ECG leads

Answer 9

right fore
left fore
left hind

Question 10

Why do you use 3 leads

Answer 10

you may see something in one lead but not the other

Question 11

What is the P wave

Answer 11

atrial depolarisation

Question 12

What is the PQ interval

Answer 12

contraction and relaxation of the atria

Question 13

What is the QRS wave

Answer 13

ventricular depolarisation

Question 14

What is the T wave

Answer 14

ventricular depolarisation

Question 15

Why perform an ECG

Answer 15

assess rate and rhythm of heart

Question 16

what does ECG mean

Answer 16

electrocardiogram

Question 17

What does an ECG show

Answer 17

electrical activity of the heart

Question 18

What can cause artefacts in ECG

Answer 18

interference
movement of the limbs
purring

Question 19

What is normal sinus rhythm

Answer 19

normal impulse originates in the SAN

Question 20

What is sinus arrhythmia

Answer 20

rhythm is irregular because the rate increases with respiration

Question 21

What are dysrhythmias

Answer 21

abnormal heart rhythms

Question 22

What are bradydysrhythmia’s

Answer 22

low heart rate

Question 23

What is sinus arrest

Answer 23

Flat line sandwiched between a regular rhythm

Question 24

What is a fist degree AV block

Answer 24

P wave and QRS complex are normal but the P-R interval is prolonged

Question 25

What is a second degree AV block

Answer 25

P wave is not conducted through the AV node, a P wave with no QRS

Question 26

What is a 3rd degree AV block

Answer 26

persistent failure of conduction through AV node, ventricles pace themselves, wide and bizarre escape complexes

Question 27

What is tachdysrhythmias

Answer 27

high heart rate

Question 28

what is supraventricular tachydysrythmias

Answer 28

supraventricular premature comlexes, premature P wave interrupts normal P wave rhytm, QRST is usually normal, atrial fibrillation

Question 29

What is ventricular tachydysrhythmias

Answer 29

ventricular origin, ventricles contract prematurely, wide and bizarre QRST complex

Question 30

What is MEA

Answer 30

mean electrical axis

Question 31

Where do you place lead 1

Answer 31

right fore to left fore

Question 32

Where do you place lead 2

Answer 32

right fore to left hind

Question 33

Where do you place lead 3

Answer 33

left fore to left hind

Question 34

a long P wave is suggestive of

Answer 34

left atrial enlargement

Question 35

a tall P wave is suggestive of

Answer 35

right atrial enlargement

Question 36

a tall QRS complex is suggestive of

Answer 36

right ventricular enlargement

Question 37

a wide QRS complex is suggestive of

Answer 37

left ventricular enlargement

Question 38

what is the mean alectricl axis

Answer 38

represents the predominantdiraction of depolarisation during excitation of the ventricles

Question 39

What is tachycardia

Answer 39

fast heart rate

Question 40

What is bradycardia

Answer 40

slow heart rate

Question 41

In which part of the QRST complex would AV nodal disease be manifested

Answer 41

PQ interval