Clinical features and prognosis of prosthetic valve endocarditis due to Staphylococcus aureus.

Purpose: Staphylococcus aureus prosthetic valve endocarditis (SAPVE) is a serious infection with high mortality. The main objective of this study was to identify factors associated with in-hospital mortality.

Methods: From January 2008 to December 2021, consecutive patients from a Spanish cohort of infective endocarditis with a definitive diagnosis of SAPVE were analyzed.

Results: During the study period, 219 cases of definitive SAPVE were diagnosed, which accounted for 16.7% of a total of 1309 cases of definitive prosthetic valve endocarditis (PVE). Patients presented advanced age and marked comorbidity. There was a higher incidence of persistent bacteremia, septic shock, stroke, and acute kidney injury than in cases of PVE caused by other microorganisms. Methicillin resistance was not associated with differences in clinical presentation, echocardiographic findings, or mortality. Only 50.6% of the patients with surgical indications (88 patients) underwent surgery. Overall, in-hospital mortality was 47.9%. The variables associated with in-hospital mortality were age (OR:1.03, 95% CI: 1.00-1.05; p = 0.016), heart failure (OR:2.86, 95% CI: 1.53-5.32; p = 0.001), acute kidney injury (OR:2.42, 95%CI:1.28-4.58; p = 0.006), stroke (OR:3.53, 95%CI:1.79-6.96; p < 0.001) and surgery indicated but not performed (OR:2.01, 95%CI:1.06-3.8; p = 0.030). On the other hand, the performance of surgery per se in patients with SAPVE, regardless of whether there was a surgical indication according to the guidelines, was not associated with a reduction in in-hospital mortality.

Conclusions: SAPVE is characterized by high mortality, which is more marked in patients who present a surgical indication but do not undergo surgery.