Infective Endocarditis Echocardiography


  • TOE superior to TTE (90% vs 50% sensitive)
  • echocardiographic findings are part of the major and minor criteria for diagnosis of infectious endocarditis
  • prosthetic valve endocarditis requires ECHO technicians that understand the type of valve (bioprosthestic, homograft, mechanical) and the normal findings


Helpful in:

(1) finding vegetation and determining size
(2) diagnosing complications -> paravalvular abscess and fistula
(3) examining underlying morphology
(4) assess severity of valve function (regurgitation)
(5) cardiac function
(6) imaging of other heart valves


Use the Modified Duke Criteria (see Duke Criteria for Infective Endocarditis)

  • Two major criteria, or
  • One major and three minor criteria, or
  • Five minor criteria

Major criteria

  • Positive blood culture for Infective Endocarditis 
    Typical microorganism consistent with IE from 2 separate blood cultures, as noted below:
    — viridans streptococci, Streptococcus bovis, or HACEK group, or
    —community-acquired Staphylococcus aureus or enterococci, in the absence of a primary focus
    or Microorganisms consistent with IE from persistently positive blood cultures defined as:
    — 2 positive cultures of blood samples drawn >12 hours apart, or
    — all of 3 or a majority of 4 separate cultures of blood (with first and last sample drawn 1 hour apart)
  • Evidence of endocardial involvement
    Positive echocardiogram for IE defined as :
    — oscillating intracardiac mass on valve or supporting structures, in the path of regurgitant jets, or on implanted material in the absence of an alternative anatomic explanation, or
    — abscess, or
    —new partial dehiscence of prosthetic valve
  • New valvular regurgitation (worsening or changing of preexisting murmur not sufficient)

Minor criteria

  • Predisposition: predisposing heart condition or intravenous drug use
  • Fever: T> 38.0° C (100.4° F)
  • Vascular phenomena: major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhages, and Janeway lesions
  • Immunologic phenomena: glomerulonephritis, Osler’s nodes, Roth Spots, and rheumatoid factor
  • Microbiological evidence: positive blood culture but does not meet a major criterion as noted below¹ or serological evidence of active infection with organism consistent with IE
  • Echocardiographic findings: consistent with IE but do not meet a major criterion as noted above

¹ Excludes single positive cultures for coagulase-negative staphylococci, diphtheroids, and organisms that do not commonly cause endocarditis.

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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