Murmur Timing

Mnemonic

“Systolic murmurs are between S1 and S2; diastolic murmurs are after S2”, and the timing narrows the lesion to a pair:

Systolic

• Ejection systolic, crescendo-decrescendo: aortic stenosis, pulmonary stenosis, hypertrophic cardiomyopathy, flow murmurs
• Pansystolic, uniform: mitral regurgitation, tricuspid regurgitation, ventricular septal defect
• Late systolic: mitral valve prolapse, with a mid-systolic click

Diastolic

• Early diastolic, decrescendo: aortic regurgitation, pulmonary regurgitation
• Mid-diastolic, rumbling: mitral stenosis, with an opening snap

“Right sided murmurs increase on Inspiration” gives RILE: Right on Inspiration, Left on Expiration.

Manoeuvres that reduce preload (standing, Valsalva) increase the murmurs of hypertrophic cardiomyopathy and mitral valve prolapse and reduce every other, which is the way to distinguish hypertrophic cardiomyopathy from aortic stenosis.

Expansion

Systolic murmurs - blood is being ejected or leaking backwards during contraction

• Aortic stenosis and pulmonary stenosis (ejection systolic)
• Mitral regurgitation and tricuspid regurgitation (pansystolic)
• Ventricular septal defect (pansystolic)

Diastolic murmurs - always pathological

• Aortic regurgitation and pulmonary regurgitation (early diastolic)
• Mitral stenosis and tricuspid stenosis (mid-diastolic)

The rule is that a valve makes a noise when it is open and narrowed or shut and leaking. Since the aortic valve is open in systole, aortic stenosis is systolic and aortic regurgitation diastolic; the mitral valve is the mirror image.

Manoeuvres help: inspiration accentuates right-sided murmurs (RILE, right on inspiration, left on expiration), and left-sided murmurs are louder in expiration.