Endocarditis Following Valve Replacement with Bioprostheses

Summary

Since 1977, 549 bioprostheses have been implanted in 511 patients (277 aortic, 267 mitral and 5 tricuspid). During the same period of time, 13 of these patients and one additional patient operated upon elsewhere were subjected to reoperation after a mean interval of 18 months.

Causes of reoperation were 2 calcifications in children 26 months postoperativety, 2 thrombotic occlusions 8 months following valve replacement and one month after stopping anticoagulation, 2 paravalvular leakages without valve destruction or evidence of inflammation after 8 months, and 8 valve destructions due to endocarditis 18 months postoperatively. Prior to endocarditis all patients had a trivial infection or dental therapy (38%), 2 patients had pneumonia, 2 cholelithiasis, one chronic Pyelonephritis and one a prostatic operation. Two patients suffered cerebral embolism in this time.

In 50% of all patients preoperative blood cultures were positive. Cultures obtained intraoperatively were positive in 5 patients. The bioprostheses showed endocarditic lesions as vegetations, perforations and calcifications.

The reoperation rate due to valve endocarditis was 1.6% over 22 months. The high incidence of feverish infections and other diseases predisposing to bacterial infections prior to valve dysfunction justifies the liberal application of prophylactic antibiotic treatment in these situations. The unknown long-term durability limits the indications for bioprosthetic valve replacement today.

Key words

Bioprosthetic endocarditis - Reoperation rate - Antibiotic prophylactic treatment - Indications for bioprosthetic valve replacement - Causes of reoperation