ECG

Question 1

What are some causes of tachycardia?

Answer 1

Exercise
Pain
Anxiety
Pregnancy
Anaemia
Shock
Hypovolaemnia
Fever
Thyrotoxicosis
PE

Question 2

What are some causes of bradycardia?

Answer 2

Fitness
Hypothermia
Hypothyroid
SA node disease
Beta blocker

Question 3

What are some causes of left-axis deviation?

Answer 3

Inferior MI
LBBB
LVH/strain
WPW
VT

(less important: conduction defects, left anterior fascicular block, obesity, pregnancy, congenital heart defects)

Question 4

What are some causes of right-axis deviation?

Answer 4

PE
RVH/strain (2 to COPD)
Antero-lateral MI
WPW

(less important: left posterior fascicular block, tall and thin)

Question 5

What causes absent P waves?

Answer 5

AF
SVT
SA block

Question 6

What causes bifid P waves?

Answer 6

P mitrale - Left atrial enlargement - MS/HF

Question 7

What causes tall P waves?

Answer 7

Pulmonary HTN (primary, secondary to PE or COPD)
Pulmonary stenosis
Tricuspid stenosis

Question 8

What causes inverse P waves?

Answer 8

Dextrocardia

Question 9

What causes peaked P waves?

Answer 9

P pulmonale - right atrial hypertrophy

Question 10

What causes a prolonged PR interval?

Answer 10

Heart block

Question 11

What causes a shortened PR interval?

Answer 11

WPW syndrome
LGL syndrome
HOCM
Duchene’s muscular dystrophy

Question 12

What causes pathological Q waves?

Answer 12

Old full thickness MI

Question 13

What causes low amplitude QRS complex?

Answer 13

Incorrect calibration
Obesity
COPD
Pericardial effusion
Myxoedema

Question 14

What causes tall R waves in V1?

Answer 14

RVH
RBB
PE
Posterior MI
Myocarditis
WPW syndrome

Question 15

What causes deep S waves in V1/2 and tall R waves in V5/6?

Answer 15

LVH

Question 16

What causes a slurred upstroke (i.e. delta wave)?

Answer 16

WPW

Question 17

What causes a broad QRS complex?

Answer 17

VT/VF
Hyperkalaemia
Complete AV block/3rd degree (Bradycardia)
BBB

Question 18

What causes a narrow QRS complex? (<3 small squares)

Answer 18

Normal
SVT
AF

Question 19

What causes LBBB?

Answer 19

• IHD/STEMI
• Cardiomyopathy
• LVH (aortic stenosis, HTN)
• Conduction system fibrosis

Question 20

What causes RBBB?

Answer 20

• IHD
• Cardiomyopathy
• PE
• RVH
• Atrial septal defect
• Ebstains abnormality

Question 21

What causes a long QT segment?

Answer 21

Hypothermia
Hypocalcaemia, hypokalaemia, hypomagnesemia
Congenital
Drugs: TCAs, chloroquine, class a1 anti-arrhythmic drugs
MI, myocarditis
Cerebral injury

Question 22

What causes a short QT segment?

Answer 22

Hyperthermia
Hypercalcaemia
Digoxin

Question 23

What causes ST depression?

Answer 23

MI - myocardial ischaemia
Digoxin, quinidine
Ventricular hypertrophy

Question 24

What causes ST elevation?

Answer 24

MI - acute full thickness myocardial infarction.
Prinzmetal angina
Left ventricular aneurism

Question 25

What causes a downwards slopping ("reverse tick") ST depression?

Answer 25

Digoxin

Question 26

What causes widespread saddle-shaped ST elevation?

Answer 26

pericarditis

Question 27

What causes tall T waves?

Answer 27

Acute STEMI | Normal

Question 28

What causes tall tented T waves?

Answer 28

hyperkalaemia

Question 29

What causes small T waves?

Answer 29

Hypokalemia Pericardial effusion Hypothyroidism

Question 30

What causes inverted T waves?

Answer 30

Normal • III, aVR, V1 ``` General • ischaemia • Bundle branch blocks (V4 – 6 in LBBB and V –V3 in RBBB) • PE • LVH • Hypertrophic cardiomyopathy ```

Question 31

What causes biphasic T waves?

Answer 31

Ischemia | Hypokalaemia

Question 32

What causes flat T waves?

Answer 32

``` Ischaemia Electrolyte imbalance (hypokalaemia) ```

Question 33

What causes inverted T waves in V1-4?

Answer 33

* Normal in children and black people * RBBB * PE

Question 34

What causes inverted T waves in V2-5?

Answer 34

* Non q wave MI * Myertrophic cardiomyopathy * SAH * Lithium

Question 35

What causes inverted T waves in V4-6 + lateral?

Answer 35

* LVH * MI * LBBB

Question 36

What causes U waves?

Answer 36

Hypokalaemia Hypercalcaemia hyperthryroidism

Question 37

Where do you place the chest leads V1-6?

Answer 37

``` V1 - 4th ICS on right V2 - 4th ICS on left V3 - between V2 and V4 V4 - 5th ICS MCL V4 - level with V4 at left anterior axillary line V6 - level with V5 at mid axillary line ```

Question 38

What colours are each of the limb leads?

Answer 38

RA - red LA - yellow LL - green RL - black "Really Yellow and Green Bike" - clockwise starting at RA