Infective Endocarditis

Peter Zimbwa

Steven M. Gordon

RAPID BOARD REVIEW—KEY POINTS TO REMEMBER:

The diagnosis of infective endocarditis (IE) requires a high index of suspicion, as well as the assimilation of clinical, laboratory, electrocardiographic, and echocardiographic data.

MODIFIED DUKE CRITERIA

Major Criteria (M)

Microbiologic

Typical microorganism isolated from two separate blood cultures (BC)
Microorganism consistent with IE isolated from persistently positive BC
Single positive BC for Coxiella burnetii or phase 1 immunoglobulin G antibody titer to C. burnetii > 1:800

Evidence of Endocardial Involvement

New valvular regurgitation (increase or change in preexisting murmur not sufficient)
Positive echocardiogram

Minor Criteria (m)

Predisposition to IE that includes injection drug use and certain cardiac conditions:
- High risk: previous IE, aortic valve disease, rheumatic heart disease, prosthetic heart valve, coarctation of the aorta, and complex cyanotic congenital heart disease
- Moderate risk: mitral valve prolapse with regurgitation or leaflet thickening, isolated mitral stenosis, tricuspid valve disease, pulmonary stenosis, and hypertrophic cardiomyopathy
Fever >38°C (100.4°F)
Vascular phenomena (petechiae and splinter hemorrhages are excluded)
Immunologic phenomena (rheumatoid factor, glomerulonephritis, Osler nodes, or Roth spots)
Positive BC that do not meet the major criteria (serologic evidence of active infection, single isolates of coagulase-negative staphylococci and organisms rarely causing IE are excluded)

INDICATIONS FOR SURGERY IN PATIENTS WITH INFECTIVE ENDOCARDITIS

Emergency indication for cardiac surgery (same day):
- Acute aortic regurgitation (AR) with early closure of mitral valve
- Rupture of a sinus Valsalva aneurysm into the right heart chamber
- Rupture into the pericardium
Urgent indication for cardiac surgery (within 1 to 2 days):
- Valvular obstruction
- Unstable prosthesis
- Acute AR or mitral regurgitation with heart failure, New York Heart Association (NYHA) class III—IV
- Septal perforation
- Evidence of annular or aortic abscess, sinus or aortic true or false aneurysm, fistula formation, or new-onset conduction disturbances
- Major embolism + mobile vegetation >10 mm + appropriate antibiotic therapy < 7 to 10 days
- Mobile vegetation >15 mm + appropriate antibiotic therapy < 7 to 10 days
- No effective antimicrobial therapy available
Elective indication for cardiac surgery (earlier is usually better)
- Staphylococcal prosthetic valve endocarditis
- Early prosthetic valve endocarditis (≤2 month after surgery)
- Evidence of progressive paravalvular prosthetic leak
- Evidence of valve dysfunction and persistent infection after 7 to 10 days of appropriate antibiotic therapy, as indicated by the presence of fever or bacteremia, provided there are no noncardiac causes for infection
- Fungal endocarditis caused by a mold or yeast
- Infection with difficult-to-treat organisms
- Vegetation growing larger during antibiotic therapy >7 days

PROPHYLAXIS

Recommended when procedures that involve manipulation of gingival tissue or the periapical region of teeth or perforation of the oral mucosa is performed in patients with

Prosthetic cardiac valve or prosthetic material used for cardiac valve repair
Previous IE
Congenital heart disease (CHD):
- Unrepaired cyanotic CHD
- Completely repaired CHD, during the first 6 month after the procedure
- Incompletely repaired CHD, with residual defects at the site or adjacent to the site of a prosthetic patch or device
Cardiac transplantation with cardiac defects No longer recommended for genitourinary or gastrointestinal tract procedures.

SUGGESTED READINGS

Agnihotri AK, McGiffin DC Galbraith AJ, et al. The prevalence of infective endocarditis after aortic valve replacement. J. Thorac Cardiovasc Surg. 1995;110:1708-1720.

Baddour LM, Wilson WR, Bayer AS, et al. Infective endocarditis: diagnosis, antimicrobial therapy, and management of complications: a statement for health care professionals from the Committee on Rheumatic Fever, Endocarditis and Kawasaki Disease, Council on Cardiovascular Disease in the Young, and the Councils on Clinical Cardiology, Stroke, and Cardiovascular Surgery and Anesthesia, American Heart Association, and endorsed by the Infectious Diseases Society of America. Circulation. 2005;111(23):e394-e434.

Bayer AS, Bolger AF, Taubert KA, et al. Diagnosis and management of infective endocarditis and its complications. Circulation. 1998;98(25):2936-2948.

Bayer AS, Ward JI, Ginzton LE, et al. Evaluation of new clinical criteria for the diagnosis of infective endocarditis. Am J Med. 1994;96:211-219.

Ben-Ami R, Giladi M, Carmeli Y, et al. Hospital-acquired infective endocarditis: should the definition be broadened? Clin Infect Dis. 2004;38(6):843-850.

Berlin JA, Abrutyn E, Strom BL, et al. Incidence of infective endocarditis in the Delaware Valley, 1988-1990. Am J Cardiol. 1995;76:933-936.

Blumberg EA, Karalis DA, Chandrasekaran K, et al. Endocarditisassociated paravalvular abscesses. Do clinical parameters predict the presence of abscess? Chest. 1995;107(4):898-903.

Cabell CH, Jollis JG, Peterson GE, et al. Changing patient characteristics and the effect on mortality in endocarditis. Arch Intern Med. 2002;162:90-94.

Only gold members can continue reading. Log In or Register to continue