Heart sounds

Question 1

What causes the first heart sound?

Answer 1

Closure of mitral and tricuspid valves - start of ventricular systole

Question 2

What causes the second heart sound?

Answer 2

Closure of the aortic and pulmonary valves - end of ventricular systole

Question 3

Atrial systole occurs when?

Answer 3

Just after ventricular diastole

Question 4

What happens at the same time as first heart sound (lub)?

Answer 4

Aortic and pulmonary valves open - not usually heard

Question 5

What happens at the same time as second heart sound?

Answer 5

Mitral and tricuspid valves open - not usually heard

Question 6

What is atrial systole heard as?

Answer 6

Not usually heard but if it is, 4th heart sound

Question 7

When does atrial systole occur?

Answer 7

Just after ventricular diastole

Question 8

Atrial systole is responsible for what percentage of the cardiac output?

Answer 8

20%

Question 9

In atrial fibrillation, 20% of CO is…

Answer 9

missing because there is no synchronised atrial systole

Question 10

A fourth heart sound is…

Answer 10

always abnormal, usually low pitched

from atrial contraction into a non-compliant/ hypertrophied ventricle

Question 11

What are the causes of fourth heart sounds

Answer 11

Heart failure - atria contracting against thickened heart muscle/ increased pressure
Myocardial infarction
Cardiomyopathy
Hypertension (pressure overload)

Question 12

How does a fourth heart sound sound?

Answer 12

Le lub dub

Question 13

How does the third heart sound sound

Answer 13

Lub de dub

Question 14

A third heart sound is…

Answer 14

A ventricular sound: blood rushing in during rapid filling phase of early diastole

normal in children and young adults up to the age of 30
stiff or dilated ventricle reaches its elastic limit and decelerates the incoming rush of blood

Question 15

Causes of a pathological third heart sound

Answer 15

Heart failure
Myocardial infarction
Cardiomyopathy
Hypertension - pressure overload
Mitral and aortic regurgitation (volume overload)
Constrictive pericarditis - heart relaxation is restricted due to fibrotic tissue pushing backwards

Question 16

Five signs of endocarditis:

Answer 16

2 in the hands - clubbing, splinter haemorrhages
1 in the heart - changing murmurs
2 in the abdomen - splenomegaly (b/c subacute infection 6-8w - the time taken for vegetation to develop on valve) & microscopic haematuria

Question 17

Rare signs of endocarditis

Answer 17

Osler’s nodes
Roth
Janeway lesions

Question 18

Stages of clubbing

Answer 18

Increased fluctuancy of nail bed
Loss of angle
Increased curvature of nail bed
Expansion of the terminal phalanx

Question 19

What are the causes of splinter haemorrhages?

Answer 19

Most common = micro-trauma

2nd = endocarditic/vasculitic

Question 20

On general examination look for:

Answer 20

ABC - anaemia, breathlessness, cyanosis
Hands - splinters & clubbing
Pulses - radial, brachial - rate, rhythm, character, volume
Collapsing pulse test
Ask for or measure BP
Neck for collapsing pulse (Corrigan’s sign)
Then JVP

Question 21

Assessing JVP

Answer 21

Neck relaxed as internal jugular behind the sterno-mastoid which should be relaxed
Look from front and side
Looking for a pulsation not a visible vein
JVP usually has a double pulsation compared to arterial pulse - may appear to be flickering
If raised, check for sacral or peripheral oedema - sign of R. sided HF

Question 22

Examining praecordium

Answer 22

Look for scars
Apex beat - position and character
Left parasternal area - for right ventricular impulse
Check for thrills
Auscultation - bell and diaphragm from apex to neck
Patient on left side with the bell for MS
Patient sitting forward, at the end of expiration using diaphragm for AR