Heart sounds and cardiac murmurs

Question 1

What causes the first heart sound?

Answer 1

Closure of the mitral and tricuspid valves at the end of diastole

Question 2

What causes the second heart sound?

Answer 2

Closure of the aortic and pulmonary valves at the end of systole

Question 3

What causes the physiological splitting of the second heart sound and when does it occur?

Answer 3

Occurs during inspiration - inspiration increases the intrathoracic pressure and so venous return to the right side of the heart is increased
The right ventricular volume will be increased, and so the pulmonary valve closure may be slightly later than the aortic valve closure, producing the splitting of the second heart sound

Question 4

When does a third heart sound occur?

Answer 4

The third heart sound is an early diastolic filling sound occurring immediately after the second heart sound

Question 5

What causes a third heart sound?

Answer 5

Acceleration and deceleration of blood during early passive filling of the ventricle
May be physiological in otherwise healthy young patients
Likely to be pathological in older patients - indicated left ventricular systolic dysfunction

Question 6

When does a fourth heart sound occur?

Answer 6

This is a late diastolic heart sound

Question 7

What does a fourth heart sound indicate?

Answer 7

Active filling of ventricle i.e. stiff ventricle
Aortic stensosis
Hypertension
Ischaemia

Question 8

What five things should a full description of any cardiac murmur include?

Answer 8

Intensity/grading
Character & pitch
Timing
Location
Radiation

Question 9

What causes an innocent murmur?

Answer 9

Systolic flow murmur usually caused by turbulent bloodflow in the right ventricular outflow tract

Question 10

What are the characteristics of an innocent murmur?

Answer 10

Systolic 
Soft 
Usually heard in pulmonary area
Localised/no radiation
No other cardiac abnormalities

Question 11

Which murmur is an ejection systolic murmur?

Answer 11

Aortic stenosis

Question 12

Which murmur does a slow rising pulse indicate?

Answer 12

Aortic stenosis

Question 13

Which murmur does a collapsing pulse indicate?

Answer 13

Aortic regurgitation

Question 14

Which murmur does the presence of a malar flush indicate?

Answer 14

Mitral stenosis

Question 15

Which murmur is a pan systolic murmur?

Answer 15

Mitral regurgitation

Question 16

Which murmur does a tapping apex beat indicate?

Answer 16

Mitral stenosis

Question 17

Where is the murmur of aortic stenosis best heard?

Answer 17

Aortic area

Question 18

Where might the murmur of aortic stenosis radiate to?

Answer 18

Carotids

Question 19

How can you distinguish between aortic stenosis murmur radiating to the carotids or carotid bruit?

Answer 19

If there is no murmur audible in the precordium, it Is a carotid bruit

Question 20

What are some of the symptoms of aortic stenosis?

Answer 20

Breathlessness, syncope, chest pain

Question 21

Which murmur might displace the apex beat?

Answer 21

Mitral regurgitation

Question 22

Where might the murmur of mitral regurgitation radiate to?

Answer 22

Axilla

Question 23

What are some of the causes of mitral regurgitation?

Answer 23

Rheumatic heart disease
Floppy mitral valve syndrome
Endocarditis
Chordae rupture
Ischaemia or infarction of papillary muscle
Left ventricular englargement

Question 24

Which murmur is a mid-diastolic murmur?

Answer 24

Mitral stenosis

Question 25

Which murmur is an early diastolic murmur?

Answer 25

Aortic regurgitation

Question 26

Which murmur is associated with right sided heart failure?

Answer 26

Mitral stenosis

Question 27

What are some of the symptoms of mitral stenosis?

Answer 27

Fatigue
Breathlessness
Palpitations

Question 28

What are some of the causes of aortic regurgitation?

Answer 28

Marfan’s syndrome
Leaflets due to endocarditis
Rheumatic heart disease

Question 29

Which murmur is associated with cardiac cachexia?

Answer 29

Mitral stenosis