Pediatric Primary Care (75 page)

•  Innocent murmurs are typically systolic; venous hum is continuous murmur. Solely diastolic murmur is never innocent and should be referred.

•  Children with innocent murmurs typically have normal first and second heart sounds (S1 and S2) that are audible in addition to murmur. Rapid heart rates of infants, particularly febrile infants, may make it difficult to distinguish between systole and diastole.

d.  Pitch: sound frequency of murmur. Innocent murmurs typically low to medium in pitch.

e.  Quality: musical or vibratory in quality.

f.  Intensity: loudness of the murmur (
Box 25-1
).

•  Innocent murmurs, typically Grade I-II/VI. Often change in intensity with change in position: sitting to lying, standing to sitting. May change in intensity from one visit to the next.

•  No clicks or extra sounds if murmur is innocent.

4.  Types of innocent murmurs.

a.  Still's murmur.

•  Most common innocent murmur in children; occurs typically in 2- to 6-year olds.

•  Low to medium in pitch, buzzing or vibratory in nature.

•  Short murmur occurring in early systole.

•  Grade I-III/VI.

•  Loudest in supine position, diminished by standing.

•  Heard best at left lower sternal border.

b.  Pulmonary flow murmur.

•  Heard in children/adolescents.

•  Harsh murmur, blowing, nonmusical.

•  Systolic ejection murmur.

•  Grade II-III/VI.

•  Loudest in supine position, loudest on exhalation.

•  Heard best in second to third intercostal space at left sternal border.

C.  Peripheral pulmonary arterial stenosis murmur.

•  Heard frequently in infants and newborns.

•  Medium in pitch.

•  Short systolic ejection murmur.

•  Grade I-II/VI.

•  Often heard best in axillae and over back.

•  Turbulence is due to relative smallness of peripheral pulmonary arteries in newborn and angulation of takeoff of right- and left-branch pulmonary arteries from main pulmonary artery.

d.  Supraclavicular or brachiocephalic systolic murmur or bruit.

•  Heard in children, young adults.

•  Low to medium in pitch, harsh.

•  Is short, systolic murmur.

•  Grade I-III/VI.

•  Heard best above clavicles, radiates to neck.

•  Heard best in supine, sitting positions; changes with change in neck position.

e.  Venous hum.

•  Also known as cervical venous hum.

•  Continuous murmur.

•  Heard over neck, immediately below clavicles.

•  Intensity varies, loudness varies with position, activity; best heard in sitting position.

•  May disappear when head is turned toward side of murmur.

•  Murmur results from turbulence of flow as large veins converge.

E.  Diagnostic tests.

1.  When murmur is detected, refer to pediatrician or cardiologist to determine significance.

2.  Many innocent murmurs do not require further diagnostic tests after thorough history, physical, auscultatory exam.

3.  CXR, electrocardiogram, cardiac echocardiography may determine whether murmur is truly innocent.

4.  Murmurs associated with structural abnormalities (organic murmurs) may require additional diagnostic evaluation.

F.  Differential diagnosis.

1.  Congenital heart disease.

2.  Cyanotic or acyanotic disease.

3.  Acquired heart disease.

4.  Cardiomyopathy.

5.  Kawasaki disease.

6.  Rheumatic heart disease.

G.  Treatment.

1.  Innocent heart murmurs have no organic cause, no structural abnormality, therefore, no treatment required.

2.  Education of patient, family is most important treatment modality.

H.  Follow up.

1.  If innocent murmur confirmed, patients may return to usual health maintenance schedule for follow-up visits.

2.  If innocent murmur suspected, but not yet confirmed as innocent, should return for reevaluation to physician.

I.  Complications.

1.  None, since no abnormality is present.

J.  Education.

1.  Crucial for patient, family.

2.  Explain murmur as noise.

3.  Noise is result of blood flow, no structural problem.

4.  No heart disease or abnormality is present.

5.  Murmur may change or disappear with time but if persists still no problem with heart.

6.  No activity restrictions required.

7.  No treatment required.

IV. KAWASAKI DISEASE

A.  Etiology.

1.  Syndrome of acute systemic vasculitis of unknown origin.

2.  Affects mostly small- to medium-sized arteries, particularly coronary arteries.

3.  Likely of infectious origin or infection-triggered immune disorder.

B.  Occurrence.

1.  Most prominent in Japan.

2.  Children of Asian descent more susceptible than Caucasians.

3.  50% of cases in younger than 2 years of age, 80% of cases in younger than 5 years of age. Peak incidence at 1 year. Rare after 10 years of age.

4.  Boys 1.5 times > girls.

5.  1-2% of siblings affected.

6.  Recurrence rate: 1-3%.

7.  More common in winter and early spring.

C.  Clinical manifestations.

1.  Vasculitis of small- to medium-sized arteries, especially coronary arteries. May progress to aneurysm formation in coronary arteries; can lead to thrombosis or scarring, increased risk for myocardial infarction, ischemic heart disease, and sudden death.

D.  Physical findings.