Murmur

Question 1

What is an innocent murmur?

Answer 1

Innocent murmur are benign ejection systolic murmurs that occur in 80% of children at some point during childhood => very common

Question 2

What causes the innocent murmur?

Answer 2

Innocent murmur is caused due to turbulent blood flow at the outflow tract of the heart

Question 3

What are the two types of innocent (ejection) murmurs?

Answer 3

1. Venous hums
   => due to the turbulent blood flow in the great veins returning to the heart.
   => heard as a continuous blowing noise heard just below the clavicles, upper sternal edge
   => disappears when child lies down
2. Still’s murmur
   => low pitched sound, vibratory in nature heard at the mid left sternal edge
   => turbulence around a muscle band in left ventricle

Question 4

What are the characteristics of an innocent murmur?

Answer 4

1. Soft-blowing murmur in the pulmonary area or short buzzing murmur in the aortic area
2. may vary with posture
3. localised with no radiation
4. no diastolic component
5. no thrill
6. no added sounds i.e. clicks
7. asymptomatic
8. Sound S1+S2 normal
9. no other abnormality

Question 5

The features of an innoSent murmur all start with the letter ‘S’:

=> Soft Systolic murmur at the left Sternal edge in aSymptomatic patient.

Answer 5

INFO CARD

Question 6

How is innocent murmur managed?

Answer 6

Innocent murmurs are often more evident in febrile or anxious children or during exercise.
=> review the child in a few weeks
=> if murmur still persists after infection has resolved then consider further investigation i.e. echo.

Question 7

What are the heart murmur red flags?

Answer 7

1. Cyanosis/pallor
2. Reduced exercise tolerance, breathlessness, sweaty
3. Failure to thrive
4. Syncope / collapse

Question 8

S1 (first heart sound) = closure of atria-ventricular valves (tricuspid on right and mitral on left)

Answer 8

S2 (second heart sound) = closure of pulmonary and aortic valves (semilunar valves)