ECGs - everything else

Question 1

Draw the axis with deviation labelled

Answer 1

Question 2

What can RAD mean?

Answer 2

• RV strain/RV hypertrophy
  OR
• Left posterior fascicular block (left posterior branch of purkinje fibres)

Question 3

What does LAD mean?

Answer 3

• LV strain/LV hypertrophy
  OR
• Left anterior fasicular block

Question 4

What can cause RAD from RV strain?

Answer 4

Massive PE

Question 5

What can cause LAD from LV strain/hypertrophy?

Answer 5

• Early hypertension
• Severe aortic stenosis

Question 6

How many wires make up purkinje fibres?

Answer 6

3 - 1 right, 2 left (posterior and anterior)

Question 7

What is bifasicular block?

Answer 7

• LBBB
  OR
• RBBB + left posterior OR anterior fasciular block

Question 8

What is complete heart block?

Answer 8

All blocked - LBBB (2) + RBBB (1)

Question 9

What is trifasicular block?

Answer 9

• 2 and a bit wires blocked
• RBBB + LPFB/LAFB
• PR prolongation

Question 10

What happens if trifascicular block and experiencing loss of conc?

Answer 10

Pacemaker needed - episodes of heart stopping
If this is NOT happening - we do NOTHING for trifasciular block

Question 11

3 types of P waves

Answer 11

1. Mitrale - M shaped
2. Normal
3. Pulmonale - tented up

Question 12

Cause of p wave mitrale

Answer 12

• Was rheumatic fever
• Now often suggests large left atria

Question 13

Cause of p wave pulmonale

Answer 13

• Cor pulmonale
• RA increased size

Question 14

3 types of PR interval

Answer 14

Long
normal
Short

Question 15

PR interval is measured from…

Answer 15

P wave to QRS complex start

Question 16

Normal PR interval

Answer 16

120 - 200ms
3-5 small squares

Question 17

When to be concerned aboit a PR interval (3)

Answer 17

1. Very long - more than 280ms
2. Other conductive tissue disease eg axis deviation?
3. Infective endocarditis of aortic valve - sign of aortic root abscess

Question 18

When is PR interval short?

Answer 18

When depolarisation is via an accessory pathway - AV node cannot conduct quicker than 0.12 ms

Question 19

When is WFW present?

Answer 19

Often when someone is relaxed
Stress free
Caffeine can mask symptoms

Question 20

What is Q wave a sign of?

Answer 20

Full thickness myocardial infarction

Question 21

Criteria for Q wave to be a Q wave

Answer 21

1. very 1st deflection after P wave
2. 1/4 of R wave
3. In lead III there is no Q wave unless in lead II and avF or V1 and V2 etc

Question 22

When to comment on Q waves?

Answer 22

Not really ever unless they are pathological ones

Question 23

Questions to ask about QRS complex?

Answer 23

1. Is there BBB?
2. Is there LVH?

Question 24

Normal QRS width

Answer 24

Ideally within 1 small square
Needs to be more than 120ms to be BBB (3 small squares)

Question 25

Where to look for 1st for BBB?

Answer 25

Chest leads - if they are not broad there is incomplete BBB

Question 26

How to tell if L or R BBB?

Answer 26

Look at V2
Is it under isoelectric line - Left
Is it above in M shape - R

Question 27

How to tell if there is LVH?

Answer 27

1. If S wave in V1 or V2 plus (add) R wave in V5 or V6 is more than 35mm
2. If any S or R wave in chest lead is more than 30mm
3. R wave in lead I plus (add) avL is more than 14mm

each small square is 1mm

Question 28

two types of ST elevation

Answer 28

• MI shaped - regional to leads
• Pericarditis - saddle shaped, widespread

Question 29

What ECG change do you get other than ST elevation in pericarditis?

Answer 29

PR depression - 1mm

Question 30

Different types of ST depression

Answer 30

1. Upsloping - nothing
2. Horizontal - less reliable
3. Downsloping - worst

Question 31

6 types of T waves

Answer 31

• Normal
• Peaked
• Biphasic
• Flattened
• Inverted
• Markedly inverted
• Assymetrically inverted - strain on heart

All others apart from normal and assym suggest ACS