Zimmerli W, Foiada M, Grädel E, Stulz P
Abteilung für Infektiologie, Kantonsspital Basel.
Schweiz Med Wochenschr. 1992 Feb 22;122(8):266-8.
In a retrospective study of 30 patients in whom a valve was replaced during active endocarditis, the role of the concomitant antimicrobial therapy was analyzed. In 75% of the patients with less than 1 week of adequate treatment before surgery, but only in 13% (p less than 0.001) with at least 1 week of therapy, could the microorganism be cultivated from the excised valve. Patients with bacteria on the valve had a 4-fold increased risk for prosthetic valve endocarditis and 2.7-fold more frequent paravalvular leakage. Therefore, in the absence of severe cardiac failure, the valve replacement should not be performed before the second week of therapy. Patients in whom microorganisms can be cultivated from the valve need a complete postoperative course of antimicrobial therapy.