Heart Murmur

Question 1

What are the features of an innocent murmur?

Answer 1

• Soft early to mid systolic murmur
• Never heard in diastole
• Left sternal edge with minimal radiation
• Normal heart sounds (physiological splitting S2)
• No clicks or associated thrill
• Variation with respiration 
	○ Increase with inspiration 
• Variation with posture
	○ Audible when supine
	○ Disappears when erect
	○ Increases with squatting

Question 2

What are the types of innocent murmurs? Which is the most common?

Answer 2

1. Still’s vibratory murmur (most common)
2. Pulmonary flow murmur
3. Branch pulmonary stenosis
4. Venous hum

Question 3

Still’s murmur:

• typical age heard
• describe the murmur, inc where/when its loudest

Answer 3

• Low to medium pitched (musical)
• Early to mid-systolic
• Crescendo then decrescendo
• Maximal at LLSE
• Louder when supine, disappears when child sits up

Question 4

Pulmonary flow murmur:

• typical age heard
• describe the murmur, inc where its loudest

Answer 4

• Typically children to adolescents
• Ejection to mid systolic peak
• 2nd-3rd interspace LUSE
• Medium to high pitch

Question 5

What are the pathological DDx for a pulmonary flow murmur

Answer 5

• ASD - careful assessment for splitting S2
• Pulmonary valve stenosis–ejection click, longer duration, higher pitch, often associated thrill
○ Often need echo to differentiate

Question 6

Branch pulmonary stenosis:

• typical age heard
• describe the murmur

Answer 6

• Infants typically < 6 months
• Murmur as per pulmonary flow (ES< LUSE, decrescendo)
• Difference: radiates to left and right axilla and back (i.e. can be heard over lung fields)

Question 7

Venous hum: describe the murmur, and when it is louder.

Answer 7

• Low pitch continuous murmur
  
  • Continuous = runs through systole and travels through diastole
• Louder when erect
• Quieter when head turned away or jugular vein compressed

Question 8

Why must a venous hum be investigated further, and why?

Answer 8

Distinguish b/n PDA and venous hum: PDA louder on left in MCL

Question 9

Give some examples for more serious features of murmurs, which should be referred to a cardiologist.

Answer 9

• Refer any child < 1 year for opinion
• Loud murmur (> Grade III)
• Diastolic and continuous murmurs
• Obvious or fixed splitting of S2
• Absent respiratory variation
• If febrile/anaemic/unwell
• Pansystolic - likely pathological
• Additional sounds e.g. clicks
• Loudest at upper left sternal edge (could be pulmonary flow, but may be serious)