Relevance of clinical presentation and period of diagnosis in prosthetic valve endocarditis.

BACKGROUND AND AIM OF THE STUDY: The study aim was to describe the characteristics of prosthetic valve endocarditis (PVE) and the clinical presentation in relation to the period of diagnosis. METHODS: In this observational, prospective, multicenter study, data acquired from 100 consecutive cases of PVE were recorded. The period of diagnosis was defined as the time elapsed from valve implantation surgery to the PVE diagnosis. PVE was classified as early (EPVE) if diagnosed during the first eight weeks, intermediate (IPVE) from nine weeks to one year, and late (LVPE) if diagnosed after one year. Variables related to the period of diagnosis and causal microorganisms were compared using a chi-square test. A logistic regression analysis was made for any diagnosis delay greater than 15 days from the first symptoms, periannular extension, surgery, and death during hospitalization. RESULTS: In total, data were collected from 24 patients with EPVE, 29 with IPVE, and 47 with LPVE. Some 59% of the IPVE episodes were caused by low-virulence microorganisms, compared to 29% of the EPVE episodes and 28% of the LPVE episodes (p = 0.017). Similarly, 66% of the IPVE episodes had a diagnosis delay longer than 15 days compared to 50% for LPVE and 20% for EPVE (p = 0.034), while 38% of the EPVE cases presented with fever and severe dyspnea compared to 10% of IPVE and 4% of LPVE cases (p = 0.001). In addition, 24% of the IPVE cases presented as fever and cardiac conduction disturbances, versus 4% for EPVE and 11% for LPVE (p = 0.08). When comparing EPVE with IPVE, the latter had a 69% periannular extension versus 38% for EPVE (p = 0.02) and 48% mortality versus 25%, respectively (p = 0.082). In a multivariate analysis, IPVE was related to the periannular extension of infection compared to EPVE (OR 3.4, 95% CI 0.98-12.1, p = 0.054). Death depended on the periannular extension of infection (OR 3.4, 95% CI 1.3-8.8, p = 0.011) and septic shock during hospitalization (OR 6.9, 95% CI 2.0-23.7, p = 0.002). CONCLUSION: When diagnosed between nine weeks and one year after valve implantation, IPVE presented with low-grade clinical manifestations, a greater delay in diagnosis, a longer periannular extension and a poorer prognosis than did EPVE.