Risk factors and management of endocarditis after mitral valve repair.

BACKGROUND AND AIMS OF THE STUDY: The authors' nine-year experience with patients requiring mitral valve reoperations for endocarditis after previous mitral valve repair is reported. METHODS: Between June 1991 and June 2000, 1,275 mitral valve repairs were performed at the authors' institution. During this time, nine patients with prior mitral valve repair presented with mitral valve (non-recurrent) endocarditis requiring surgical correction. Etiology at the initial mitral valve repair was ischemic in four patients (44%), floppy valve in one patient (11%), Libman-Sacks endocarditis in one (11%), irradiation-induced degeneration in one (11%), and endocarditis in two cases (22%). Median patient age was 61 years (range: 36-81 years). Median ejection fraction was 50% (range: 23-70%), and seven patients (78%) presented urgently or emergently. The median time interval between the two procedures was 8.6 months (range: 28 days to 14.3 years). RESULTS: Certain risk factors were identified in these patients, including systemic infections, prosthetic implants in the bloodstream, and subsequent invasive procedures. The mitral valve was re-repaired in one patient (11%), while eight patients (89%) required valve replacement. All required excision of the ring. Hospital mortality was 11% (n = 1). Postoperative complications included perioperative myocardial infarction in two cases (25%), low cardiac output in two (25%), and prolonged ventilatory support in four (50%). There was no perioperative stroke, and no late recurrence of endocarditis. CONCLUSION: The study findings suggest that the incidence of (non-recurrent) endocarditis after mitral valve repair requiring surgical intervention is infrequent. Attempts at re-repair may be successful only in selected patients. Reoperation was accomplished with acceptable morbidity and mortality, and often required mitral valve replacement; however, late results indicated the absence of prosthetic valve endocarditis.