Prosthetic valve endocarditis (PVE) remains an uncommon but serious complication of cardiac valve replacement. Operative intervention is frequently required in its management, although timing and outcome are incompletely defined. We reviewed cases of PVE in 75 patients who underwent valve replacement at Stanford University Medical Center from August, 1966, to September, 1981. Patients were classified into two groups. The healed PVE group included those patients who had completed a planned course of antibiotic therapy (N = 12); operations performed prior to completion of such a course defined the active PVE group (N = 63). Average age for both groups was 53 years, with men predominating at a ratio of 2:1. Indications for operation included congestive heart failure (87%), recurrent emboli (15%), and persistent sepsis (4%). Staphylococcal and streptococcal organisms accounted for 47% of late PVE cases (occurring after 60 days; N = 58). Staphylococcal organisms were the primary causative agents in 43% of cases of early PVE (occurring before 60 days; N = 7). The operative mortality rate for all patients with PVE was 23% (25% for active PVE, 8% for healed PVE); deaths were caused principally by myocardial or multiple system failure present before operation. The primary predictors of operative mortality, as determined by multiple regression analysis, were emboli, renal dysfunction, type of PVE, and valve site. Operative mortality for the subgroup with active early PVE was 57%. At the present time, 29 of 47 operative survivors with active PVE (62%) and 8 of 11 patients with healed PVE (73%) are living, with the average postoperative interval being 3.8 years (range, 2 months to 15 years). There was no correlation between duration of preoperative antibiotic therapy and either intraoperative bacteriological findings or operative outcome. The 5-year actuarial survival rate (mean ± standard error of the mean) of patients with active PVE discharged from hospital was 54 ± 9%. Recurrent/residual endocarditis occurred in 7 patients (15%) with active PVE; actuarial analysis showed 76 ± 8% of active PVE patients to be free of recurrent/residual endocarditis at 5 years. Postoperative peri-prosthetic leakage developed in 12 patients (26%) with active PVE, necessitating replacement in 10; actuarial analysis showed 65 ± 9% of patients to be free of periprosthetic leak at 5 years. The multivariate predictor of an overall unsatisfactory result (defined in terms of early and late cardiac deaths and operations for recurrent/residual endocarditis, or periprosthetic leak, or both) was the type of endocarditis—early active PVE, late active PVE, and healed PVE. When this classification was removed from the multiple regression analysis, preoperative renal dysfunction emerged as the main predictor of an overall unsatisfactory result. Earlier surgical intervention before these risk factors develop should result in fewer complications and a higher survival rate.
ASJC Scopus subject areas
- Pulmonary and Respiratory Medicine
- Cardiology and Cardiovascular Medicine