Prosthetic valve endocarditis resulting from nosocomial bacteremia. A prospective, multicenter study.
OBJECTIVE
To determine the incidence of endocarditis in bacteremic patients with prosthetic heart valves and the risk factors for and the effect of duration of antibiotic therapy on development of endocarditis in such patients.


METHODS
Multicenter, prospective observational study.


METHODS
Six university teaching hospitals with high-volume cardiothoracic surgery.


METHODS
One hundred seventy-one consecutive patients with prosthetic heart valves who developed bacteremia during hospitalization.


RESULTS
Patients were evaluated when they were identified as having bacteremia and 1, 2, 6, and 12 months after its occurrence. Of 171 patients, 74 (43%) developed endocarditis: Fifty-six (33%) had prosthetic valve endocarditis at the time bacteremia was discovered ("endocarditis at outset"), whereas 18 (11%) developed endocarditis a mean of 45 days after bacteremia was discovered ("new endocarditis"). Mitral valve location and staphylococcal bacteremia (Staphylococcus aureus or S. epidermidis) were significantly associated with the development of "new" endocarditis. All 18 cases of new endocarditis were nosocomial, and in 6 of these cases (33%) bacteremia was acquired via intravascular devices. Twenty-one patients without evidence of endocarditis at the time of bacteremia received short-term antibiotic therapy (< 14 days); 1 patient (5%) developed endocarditis. Eleven of 70 patients (16%) who received long-term antibiotic therapy (> 14 days) developed endocarditis (P > 0.2).


CONCLUSIONS
Bacteremic patients with prosthetic heart valves were at notable risk for developing endocarditis, even when they received antibiotic therapy before endocarditis developed and regardless of the duration of such therapy. Intravascular devices were a common portal of entry.
Fang
G
G
University of Pittsburgh, Pennsylvania.
Keys
T F
TF
Gentry
L O
LO
Harris
A A
AA
Rivera
N
N
Getz
K
K
Fuchs
P C
PC
Gustafson
M
M
Wong
E S
ES
Goetz
A
A
Wagener
M M
MM
Yu
V L
VL
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016470:Bacteremia / Q000150:complications* / Q000382:microbiology; D003428:Cross Infection / Q000150:complications*; D004334:Drug Administration Schedule; D004697:Endocarditis, Bacterial / Q000209:etiology* / Q000401:mortality / Q000517:prevention & control; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016459:Prosthesis-Related Infections / Q000209:etiology* / Q000401:mortality / Q000517:prevention & control; D012307:Risk Factors
D000900:Anti-Bacterial Agents