Murmur (Cardiac Murmur)

Last updated 20.09.12

Definition

-  Disruption of normal lub-dub heart sounds

-  May pathological or physiological

 

Features

-  Normally detected by stethoscope but may be ausible to naked ear

-  Systolic murmurs may present in pregnancy & are usually benign

-  Diastolic murmurs in pregnancy are pathological

 

Associated S/S

-  Cardiomegaly

-  Peripheral oedema

 

Cause

-  Aortic Stenosis (AS)

-  Aortic Sclerosis

-  Aortic Regurgitation (AR)

-  Mitral Stenosis (MS)

-  Mitral Regurgitation (MR)

-  Pulmonary Stenosis (PS)

-  Pulmonary Regurgitation (PR)

-  Triscupid Stenosis (TR)

-  Triscupid Regurgitation (TR)

-  Atrial Septal Defect (ASD)

-  Ventricular Septal Defect (VSD)

-  Patent Formaen Ovale (PFO)

 

Timing

-  Time by pulse: HR w systole

-  Difficult if AF or tachycardia

-  Biggest gap between s2 --> s1

-  Systolic

-  AS, MR, PS, TR

-   Ejection: AS, aortic sclerosis

-   Pansystolic (entire): MR

-  DDx: aortic stenosis vs sclerosis

-  Diastolic

-  AR, MS, PR, TS

-  Early, Late, Pan

-  Manouvres

-  Carvallos (Inhalation): increases right heart murmurs

-  Left lateral position: increases mitral valve murmurs 

 

Location

-  Heart sounds

-  Aortic, Pulmonary, Tricuspid, Mitral

-  Radiation

-  Axilla: MS

-  Carotids: AS

-  DDx: carotid bruit (not heard in aortic area)

-  Left sternal edge: MS

 

Grade x/6

-  1: faint, only heard in good conditions

-  2: soft but obvious

-  3: heard all over precordium

-  4: lound + thrill

-  5: heard w stethoscope partially off chest + thrill

-  6: heard w stethscope off chest + thrill

 

Best Heard w

-  Bell

-  Diaphragm

 

Systemic S/S

-  Strong pulse (wide pulse pressure): AR

-  Weak pulse: AS

-  AF: MS, MR

-  Sepsis: IE

-  Mitral Facies: MS

-  Pulmonary oedema: MS, AR

 

Why

-  RHD: MS, MR, AS

-  EtOH: dilated cardiomyopathy --> MR

-  Congenital Heart Disease (CHD): ASD, VSD

-  IE

-  HTN: LVH

 

Who

-  Infant: CHD

-  IVDU: IE

-  Pregnancy: physiological

-  Aboriginal: RHD

-  Elderly: aortic sclerosis

 

 

 

References