Innocent pediatric murmurs

Background

• 72% of all school-age children have innocent murmurs
• Congenital heart disease 0.8% of live births
• Check height and weight- left-to-right can cause decrease in weight, but are usually symptomatic.
• Color- so, so but cyanosis of hands, feet, periorally on exertion.
• Feeding- fatigue or short feeding times for infants- perspiring, grunting, coughing, tachycardia while feeding. Severe CHF may show at rest deep breathing with dyspnea with distress.
• Enlarged heart (ie ASD) can cause bulging of chest
• Older kids- activity causing dyspnea/cyanosis- keeping up with peers, grunting, coughing, tired from stairs. Syncopal/presyncopal, fatigue, palpitations/angina can occur with hypertrophic cardiomyopathy
• Yet older- Aortic valve with rheumatic fever,myocarditis (history of URI), endocarditis (IV drug use)
• Preg Hx- Diabetes M (ASD, coarctation of aorta, cardiomyopathies), CMV, Coxsackie B5, warfarin, antiseizure, EtOH (ASD,VSD), prematurity (PDA)
• Worry when- family history of HCOM/sudden death and prominent apical thrust (indicates LVH)

Differential Diagnosis

Valvular Emergencies

• Mitral stenosis
• Mitral regurgitation
  • Mitral valve prolapse
• Aortic stenosis
• Aortic regurgitation

Diagnosis

• most innocent murmurs are
  • not holo or diastolic
  • not >grade III
  • hockey stick dist
  • normal S1 & S2

Types

• Still's
  • Mid-Systolic, best at left lower sternal border, likely from harmonic vibrations of LV outflow tract (chordae tindinae). All ages, particularly young school age. Low pitch, musical. Decr. with inspiration, sitting, standing. Not a VSD- not regurgitant or with thrill. VSD - HSM
• Innocent Pulmonary Flow Murmur
  • Systolic best at left upper sternal border, minor turbulence in RV outflow tract and main pulmonary artery.
  • Often infants and preschool age. Higher pitched than still's, less musical.
  • Not PS- no ejection click, no increased RV impulse. no wide s2 split
  • Not Pulm M of ASD, no fixed splitting, no diastolic tricuspid flow rumble, no increased RV impulse.
  • Decreased on inspiration/sitting/standing.
• Innocent Pulmonary Branch Murmur of Infancy
  • Systolic ejection murmur from turbulence in pulmonary artery branches (one or both). Medium pitch.
  • Physiologic in neonates, becoming audible at L,R,B USB between 0-2wks
  • transmits well to back and axilla. common in premature; disappears early in infancy.
  • Not PS- no ejection click, no increase in RV impulse.
• Supraclavicular Bruit
  • Systolic ejection murmur of med pitch from physiologic turbulence of carotid/subclavian and heard at base of neck.
  • Can be palpable. Disappears on hyperextension of shoulders.
  • Not AS which is loudest at URSB with systolic thrill, sometimes with click.
• Venous Hum
  • Continuous murmur from turbulent flow in SVC heard at L,R,or B infraclavicular position while sitting/standing
  • Not PDA (bounding pulse, systolic>diastolic sound) or AV malformation. Disappears in recumbent position, rotation of head, by pressure at jugular.
• Mammary Souffle
  • Blood flow in A and V to engorged breast. - systolic or continuous, disappears with stethoscope pressure.
• Cardiorespiratory murmur
  • High pitched cooing, anywhere, but especially apex.
  • Breath sound so not timed to heart, disappear when holding breath.

See Also

• Heart Murmurs
• Valvular Emergencies (Valve)