Heart Murmur Characteristics
Systolic murmurs occur during S1-S2 (aortic stenosis, mitral regurgitation), diastolic murmurs occur during S2-S1 (aortic regurgitation, mitral stenosis).
Detailed Explanation
Systolic Murmurs (S1 to S2):
1. Aortic Stenosis (AS):
- Crescendo-decrescendo (diamond-shaped)
- Radiates to carotids
- Best heard at right upper sternal border
- Pulsus parvus et tardus
2. Mitral Regurgitation (MR):
- Holosystolic/pansystolic
- Radiates to axilla
- Best heard at apex
- S3 may be present
3. Tricuspid Regurgitation:
- Holosystolic
- Increases with inspiration (Carvallo's sign)
Diastolic Murmurs (S2 to S1):
1. Aortic Regurgitation (AR):
- Early diastolic, decrescendo
- High-pitched "blowing"
- Best heard at left sternal border leaning forward
- Wide pulse pressure
2. Mitral Stenosis (MS):
- Low-pitched rumble
- Opening snap after S2
- Best heard at apex with bell
Clinical Correlation
Severe aortic stenosis causes syncope, angina, and heart failure (SAD mnemonic). Once symptoms develop, survival without valve replacement is significantly reduced.
Memory Trick
"PASS the Systole" - Pansystolic = AS (stenosis), MR, TR. Diastolic murmurs are harder to hear - think "quiet time" between S2-S1.