Evaluation and management of prosthetic valve endocarditis.

Despite improved operative technique and sophistication in managing patients undergoing cardiac valve replacement, prosthetic valve endocarditis (PVE) remains a source of major morbidity (overall recent incidence approximately 2.1%), and these patients have a high case-fatality rate (58% overall). Early PVE (less than 60 days postoperative) has a worse prognosis (78% case-fatality rate) and is usually caused by staphylococcal species, gram-negative rods, and fungi; whereas the case-fatality rate in late PVE is 46%, owing to the lower fatality of streptococcal species infections that tend to occur late. Risk factors that portend a poor clinical response to medical therapy alone include the presence of congestive heart failure, paravalvular leakage, systemic embolic, early PVE, nonstreptococcal etiology, aortic location in a nonheterograft valve, as well as persistent fever (greater than 10 days). Given the frequently dismal outcomes in the medical management of these patients, the case is made for early surgical intervention in most cases of PVE (except for late streptococcal disease), especially if any of the aforementioned risk factors are present.