CHAPTER 17: Endocarditis

DISEASE OVERVIEW

• Endocarditis is caused by, and accompanied by, bacteremia or fungemia.

• The echocardiographic hallmark is a vegetation.

• Microorganisms attract blood fibrin and platelets to form the vegetation.

Source

• Cahill TJ, Baddour LM, Habib G, et al. Challenges in Infective Endocarditis. J Am Coll Cardiol. 2017;69:325–344.

• Location of vegetations:

  • - Most commonly attached to the surface of native valve leaflets.

  • - May attach to mitral or tricuspid chordae.

  • - Difficult to localize and diagnose on prosthetic valves.

• Pacemaker/ICD wires may have to be completely removed if they become infected.

• Congenital heart defects and congenital defect repairs may become infected.

• The point of attachment varies, but there are some useful typical echo features.

• Vegetations are said to favor the upstream side of valves: Atrial side of mitral and tricuspid valves, and ventricular side of aortic valves (pulmonic valve endocarditis is rare).

• The usual appearance is a shimmering, shaggy, stippled, pedunculated mass.

• Reflectivity and texture are typically similar to normal myocardium.

• Calcification suggests chronicity.

Source

• Kini V, Logani S, Ky B, et al. Transthoracic and transesophageal echocardiography for the indication of suspected endocarditis: vegetations, blood cultures, and imaging. J Am Soc Echocardiogr. 2010;23:396–402.

• Complications:

  • - Leaflet perforation.

  • - Abscess.

  • - Fistula.

  • - Embolism.

Sources

• Anguera I, Miro JM, Vilacosta I, et al. Aorto-cavitary fistulous tract formation in infective endocarditis: clinical and echocardiographic features of 76 cases and risk factors for mortality. Eur Heart J. 2005;26:288–297.

• Sudhakar S, Sewani A, Agrawal M, et al. Pseudoaneurysm of the mitral-aortic intervalvular fibrosa (MAIVF): a comprehensive review. J Am Soc Echocardiogr. 2010;23:1009–1018.

• Thuny F, Disalvo G, Belliard O, et al. Risk of embolism and death in infective endocarditis: prognostic value of echocardiography. A prospective multicenter study. Circulation. 2005;112:69–75.

• Clinical suspicion:

  • - Persistent fever.

  • - Fever with a new murmur.

  • - Change in an existing murmur.

  • - Conduction abnormality on ECG.

  • - Embolic event.

  • - Newly diagnosed dehiscence on echo of an existing prosthetic valve.

  • - New heart failure is an ominous finding and justifies surgical intervention.

• Differential diagnosis:

  • - Calcification.

  • - Lambl ...