Where is it loudest? | When in systole? | Intensity (Levine scale*) | Other phenomena | Typical age | Likely murmur | Incidence per 10,000 live births | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Systolic murmurs | ||||||||||||
LLSB and apex | Midsytolic | Mid to loud (2 to 4 out of 6) | Enhanced by Valsalva maneuver and transition to standing; potentially associated with mitral regurgitation murmur | Early adolescence, depends on extent of outflow obstruction | Hypertrophic obstructive cardiomyopathy (audio file) | 20 | ||||||
LUSB | Midsystolic dependent on size | Soft to loud (1 to 3 out of 6) | Radiates to back, fixed split S2, less discrete respiratory variation | Variable, dependent on size of defect | Atrial septal defect (audio file) | 5.4 | ||||||
Apex | Holosystolic or Early blowing |
Mid to loud (2 to 3 out of 6) | Radiates to axilla, can have S3 | Congenital or acquired, most common valve impacted in rheumatic heart disease | Mitral regurgitation (audio file) | 5 | ||||||
Apex | Late systolic with a click | Mid to loud (2 to 3 out of 6) | Midsystolic click, enhanced by Valsalva maneuver | School aged to adolescence | Mitral valve prolapse (audio file) | 5 | ||||||
LUSB left infraclavicular area | Usually holosystolic (progresses to continuous) | Mid to loud (2 to 4 out of 6) | Machinery style; can have bounding pulses | Typically, neonate; more common in prematurity | Patent ductus arteriosus (audio file) | 5 | ||||||
Left scapular region | Variable systolic murmurs | Soft to loud (1 to 3 out of 6) | Louder murmurs commonly from coexistent aortic valve anomaly | Neonate to adulthood | Coarctation of the aorta | 4 | ||||||
RUSB with radiation to the carotids | Midsystolic | Mid to loud (2 to 3 out of 6) | 0.5% to 2% of children have a bicuspid aortic valve: many of these are missed neonatally If left ventricular outflow tract obstruction is present, a diagnosis is more likely in the neonatal period Can be associated with an ejection click |
Neonate to adulthood | Aortic stenosis (audio file) | 3.8 | ||||||
LUSB | Systolic (rarely continuous) | Mixed (1 to 3 out of 6) | Loud P2 (pulmonic component of S2) when pulmonary artery hypertension is present Radiates to back and lungs |
Frequently missed; would persist beyond peripheral pulmonary stenosis | Supravalvular pulmonary stenosis (pulmonary artery stenosis) (audio file) | < 1 | ||||||
LLSB | Holosystolic or early | Loud (2 to 3 out of 6) | Associated with hepatosplenomegaly and a pulsatile liver | Variable; Ebstein anomaly is the most common explanation | Tricuspid regurgitation (audio file) | < 1 | ||||||
Diastolic murmurs | ||||||||||||
LLSB | Mid-diastolic | Soft (1 to 2) | Uncommonly an anatomic stenosis, more likely functional from alternate pathology | Variable | Tricuspid stenosis | 30 | ||||||
Apex | Early | Soft (1 to 2) | More commonly associated with rheumatic heart disease | Toddlers (> 12 months) and adolescents | Mitral stenosis (audio file) | < 1 |