179 Clinical and echocardiographic predictors of mortality in prosthetic valve endocarditis

Abstract

Prosthetic valve endocarditis (PVE) is a rare and serious complication after heart valve replacement. Despite progress in therapeutic modalities, morbidity and mortality remain untolerably high. To evaluate the current outcome of PVE in a high volume tertiary care center in Tunisia and to analyse predictors of mortality. All cases of PVE treated in our institution between 1997 and 2008 were analysed according to the modified DUKE criteria. Univariate and multivariate analysis were performed to assess predictors of mortality. Two sided p values<0.05 were considered significant. During the study period, 234 IE were diagnosed, among them 74 were PVE (42 males and 32 females), mean age was 39.23 years. They were early PVE in 38 cases (51.4%) and late PVE in 36 cases (48.6%). 28 patients (38.7%) underwent surgical intervention during the active phase. 14 patients died during index hospitalization (i.e. 18.9% in hospital mortality). In comparison with survivors, patients who died had a considerably longer delay to diagnosis (18.9 days vs 8.89; p=0.03), more hyperleucocytosis (14678 vs 10234; p=0.015) and more severe anemia (8.56 g/dl vs 10.46g/dl). They suffered considerably more congestive heart failure (78.6% vs 10%; p<0.001) and were more likely to undergo surgery during the active phase (71% vs 30%; p=0.006). Echocardiographically, patients who died presented more frequently highly mobile vegetations (63.8% vs 17.8%; p=0.005), massive vegetations (>15mm) (44.4% vs 4.2%; p=0.013), annular abscess (38.5% vs 1.7%; p<0.001), prosthetic dehiscence (42.9%vs 17.3%;p=0.049) and prosthetic abscesses (28.6% vs 3.8%;p<0.001). Conversely, neither age nor causative organisms were associated with in hospital mortality. On multivariate analysis, the only variable strongly correlated with in hospital death was congestive heart failure (HR=27.5, p=0.005, 95% CI [2.78-276.6]). PVE remains very serious condition carrying high mortality rates.In our series, the strongest predictor of mortality was congestive heart failure.