II. Epidemiology
- Ages affected: School age to adolescence (5 to 14 years old)
III. Physiology
- Exaggerated normal vibratory ejection sound from the pulmonary vasculature
IV. Signs
- Intensity: Grade I-II of VI murmur
- Soft, early to mid-systolic murmur at left upper sternal border (between 2nd and 3rd ribs)
- Crescendo-Decrescendo murmur
- Increased murmur in high output states
- Loudest when supine and decreased when upright or during breath holding
V. Differential Diagnosis
- Atrial Septal Defect (ASD)
- Pulmonic stenosis
VI. Course
VII. Resources
- Pulmonary Flow Murmur (USMLE Clinic, YouTube)
