ECG

Question 1

How to measure HR

Answer 1

No. of R waves in 15 large squares

Multiply by 20

Question 2

Normal HR

Answer 2

60-80 BPM

Question 3

What does differing RR intervals mean

Answer 3

Heart block

Question 4

How big should P wave be

Answer 4

No more than 2 small squares

Question 5

What does PR interval signify

Answer 5

Time between start of depolarisation of atria and start of depolarisation of ventricles

Question 6

How long should PR interval be

Answer 6

120-200ms

Question 7

PR interval > 200ms

Answer 7

Heart Block

Question 8

Prolonged PR interval

Answer 8

Hypokalaemia, Acute rheumatic fever, Carditis

Question 9

QRS wave is indicator of

Answer 9

Indicator of the synchronisation of the contraction of the ventricular muscle

Question 10

QRS duration

Answer 10

Less than 120ms

Question 11

Long QRS duration means

Answer 11

Part of ventricle not contracting properly

Question 12

Lengthened QT interval meaning

Answer 12

Ventricular arrhythmia

Question 13

Large ECG signal signifies

Answer 13

Muscle membrane potential changing

Question 14

Epicardial AP length (outside) vs Endocardial AP length (inside)

Answer 14

Epicardial shorter

Question 15

Which part of muscle more susceptible to ischaemia

Answer 15

Endocardial–> reduces duration

Question 16

Endocardial muscle layer

Answer 16

inside

Question 17

Epicardial muscle layer

Answer 17

outside

Question 18

If endocardial becomes shorter compared to epicardial

Answer 18

Inverted T wave

Question 19

Class 1 Anti-arrhythmic drugs

Answer 19

Na+ channel blockers

Question 20

Class 2 Anti-arrhythmic drugs

Answer 20

Beta blockers

Question 21

Class 3 Anti-arrhythmic drugs

Answer 21

K+ channel blockers

Question 22

Class 4 Anti-arrhythmic drugs

Answer 22

Calcium channel blockers

Question 23

Sinus Bradycardia

Answer 23

HR less than 60bpm

Question 24

Sinus Tachycardia

Answer 24

HR more than 100bpm

Originates from SA node

Question 25

Ventricular tachycardia

Answer 25

180-190bpm Prolonged QRS No P wave seen Regular same pattern

Question 26

Ventricular tachycardia reasons

Answer 26

Abnormal tissues in ventricles generating rapid + irregular heart rhythm

Question 27

Ventricular Fibrillation

Answer 27

Irregular rhythm 300+ BPM No QRS No P wave

Question 28

Ventricular Fibrillation reasons

Answer 28

Different parts of heart contracting at different times Desynchronisation Irregular pattern and amplitude

Question 29

First Degree Heart block

Answer 29

PR interval >200ms | Regular rate

Question 30

First Degree Heart block reasons

Answer 30

AV node problem- can be v sensitive to electrolyte changes

Question 31

Second Degree Heart block TYPE 1 (Wenkenback)

Answer 31

PR interval gets progressively longer until P wave not followed by QRS Repeats

Question 32

Second Degree Heart block TYPE 2

Answer 32

P wave regular Rate irregularly irregular AV node randomly fails to respond to atrial impulses Often damage to AV node

Question 33

Third Degree Heart Block

Answer 33

P waves random May have bradycardia No induction from atria to ventricles- ventricles generate own signal QRS split

Question 34

Atrial Fibrillation

Answer 34

``` 100-160 BPM Irregularly irregular rhythm Normal QRS No P wave Abnormal aortic tissue- multiple excitatory focuses ```

Question 35

Atrial Flutter

Answer 35

High HR (110BPM) Regular rhythm P wave replaced by multiple F (flutter) waves Abnormal tissue is in atria- but only one abnormal excitatory focus

Question 36

Junctional rhythm

Answer 36

Damage to SA node/block in conduction pathway in atria AV node takes over as pacemaker 40-60 BPM Normally absent P wave

Question 37

Supraventricular Tachycardia (SVT)

Answer 37

140-220 BPM P wave absent/preceding T wave Higher frequency impulses at AV node

Question 38

AV node re-entrant tachycardia

Answer 38

W>M P wave hidden in QRS complex, or seen after Palpitations

Question 39

Depressed ST segments

Answer 39

Coronary ischaemia | Hypokalaemia

Question 40

STEMI

Answer 40

ST elevation in 2 or more adjacent ECG leads | 80bpm

Question 41

NSTEMI

Answer 41

less serious | areas of cardiac ischaemia but not necessarily death

Question 42

Right Bundle Branch Block

Answer 42

Problem with right side of heart

Question 43

Left Bundle Branch Block

Answer 43

Indication of heart disease

Question 44

Bundle Branch block

Answer 44

QRS Prolonged Depolarisation delay through ventricular muscle Usually due to hypoxia/ischaemia damage Notch on R wave

Question 45

Pathological Q wave

Answer 45

Larger than normal Q wave | Damage to muscle of interventricular septum