Murmurs and Valve Lesions

OVERVIEW

• Description of auscultatory findings of heart murmurs and valve disease and valvular lesions
• Heart murmurs are abnormal heart sounds believed to be caused by turbulent flow across heart valves or vascular abnormalities.
• When assessing a murmur, determine 6 characteristics: position at which it is loudest, grade, timing, duration, presence of a thrill, radiation and changes during respiration or with dynamic manoeuvers.

DESCRIPTION OF A MURMUR

(1) Timing

• systole/diastole/continuous
• early/mid/late/pan

(2) Area of greatest intensity

(3) Loudness

• grade 1 (very soft/consultants)
• grade 4 (thrill)
• grade 6 (no stethoscope required)

(4) Pitch

• low (low pressure)
• high (high pressure)

(5) Changes with Dynamic Manoeuvres

• respiration (RILE)
• squatting (makes most murmurs louder, except HOCM and MVP)
• isometric exercise (AS, HOCM and MVP softer, other murmurs louder)
• Valsalva:
  • -> straining -> HOCM and MVP softer
  • -> release -> first R sided murmurs increase then left sided

PAN-SYSTOLIC

• MR
• TR
• VSD
• Aorto-pulmonary shunts

MID-SYSTOLIC

• AS
• PS
• HOCM
• Pulmonary flow murmur of an ASD

LATE SYSTOLIC

• MVP
• Papillary muscle dysfunction (due to ischaemia or HOCM)

EARLY DIASTOLIC

• AR
• PR

MID-DIASTOLIC

• MS
• TS
• Atrial myoxoma
• AR (Austin Flint murmur – low pitched rumbling mid-diastolic and presystolic murmur @ apex -> shuddering of anterior leaflet of mitral valve)
• Carey Coombs murmur of acute rheumatic fever

PRESYSTOLIC

• MS
• TS
• Atrial myxoma

CONTINUOUS

• PDA
• Arteriovenous fistula (coronary artery, pulmonary, systemic)
• Aorto-pulmonary connection (e.g. congenital, Blalock shunt)
• Venous hum
• Rupture of sinus of Valsavla into right ventricle or atrium
• ‘Mammary souffle’ – late in pregnancy or early post partum period

PAN-SYSTOLIC MURMUR DISTINGUISHING FEATURES

References

• Robbins A, Zhang G, Cadogan M. Eponymic Cardiac Murmurs. LITFL
• Nickson C. Murmurs DDx. CCC
• Nickson C. Cardiac Lesions and Severe Clinical Signs. CCC
• Cadogan M. Echo Library. LITFL
• Otto CM, Nishimura RA, Bonow RO, Carabello BA, Erwin JP 3rd, Gentile F, Jneid H, Krieger EV, Mack M, McLeod C, O’Gara PT, Rigolin VH, Sundt TM 3rd, Thompson A, Toly C. 2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2021 Feb 2;143(5):e72-e227.
• Otto CM. Textbook of Clinical Echocardiography. Elsevier. 7e, 2023.
• Houghton AR. Making Sense of Echocardiography: A Hands-on Guide. 3e 2023