Infective Endocarditis is a microbial infection of the endothelial surface of the heart. Endocarditis usually involes the heart valves (most commonly the mitral and aortic valves). Congenital heart disease is the predominant underlying substrate for infective endocarditis in children over the age of 2 years.  The most common underlying predisposing conditions include: ventricular septal defect, patent ductus arteriosus, aortic valve abnormalities, and tetralogy of Fallot. The pathogenesis is characterized by the triad of endothelial damage, platelet adhesion, and microbial adherence to the vegetation or intact valvular tissue. Organisms such as staphlooccocus aureus, streptococcus viridans, Streptococcus pneumoniae, HACEK organisms and group A, C and G streptococci, and Candida albicans have specific surface receptors for fibronectin that promote adhesion of bacteria to thrombus formation.  The Duke criteria uses a combination of clinical, microbiological, pathologic and echocardiographic findings to help make the diagnosis. 

Echocardiographic findings: 

  • Oscillating mobile intracardiac mass or vegetation attached to valve leaflets or endocardium
  • Annular abscess
  • Prosthetic valve dehiscence
  • New valvar regurgitation 



Moss, Arthur J., and Hugh D. Allen. Moss and Adams' Heart Disease in Infants, Children, and Adolescents: Including the Fetus and Young Adult. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2008. Print.1299-1311

Lai, Wyman W. Echocardiography in Pediatric and Congenital Heart Disease: From Fetus to Adult. Chichester, UK: Wiley-Blackwell, 2009. Print 581-594