感染性心内膜炎PPT课件.ppt

7/98 Update onInfective Endocarditis Larry Baddour, MD University of Tennessee Pathogenesis Disruption of the endocardial layer as a complication of abnormal blood flow associated with underlying cardiac defect Bacterium-endothelium interaction with bacterial attachment and invasion of endothelial cells Epidemiology Underlying valvular abnormality predisposing to infective endocarditis rheumatic fevera common cause in the past mitral valve prolapsecurrently represents the most common underlying cardiac abnormality mitral valve prolapse risk for infective ednocarditis is ?5x-8x mitral regurgitation increases the risk leaflet redundancy with myxomatous degeneration is a frequent finding age 20 , female predominateage 20 , male accounts for 60%age 50 , male accounts for 68% Mitral Valve Prolapse and Infective Endocarditis Coagulase-negative Staphylococci can produce native-valve endocarditis in mitral valve prolapse usually subacute, difficult to diagnose, and disregarded as a contaminant delay in diagnosis and treatment may account for the severe complications myocardial abscess formation valvular insufficiency requiring valve surgery death Prosthetic Heart Valve positive blood culture in hospitalized patients with underlying prosthetic valves can be a harbinger of endocarditis 43% patients with nosocomial bacteremia or fungemia had prosthetic valve infection a serious complication IV Drug Use Recurrent Polymicrobial Staph aureus accounts for the majority of cases of endocarditis tricuspid valve, either alone or in combination, us most often infected Predisposing Factors Polymicrobial Infective Endocarditis Polymicrobial Infective Endocarditisclinical features IV drug use is the predominant risk factor younger age (mean 36.5 years) 2/3 were male right-sided cardiac involvement in 60% streptococci more frequent than S. aureus 1/3 of patients died mortality rate is 4x higher for pure left-sides vs pure right-sided endocarditis Diagnostic (Duke) Criteria De