Prognostic Value of 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Infective Endocarditis

BACKGROUND 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is commonly used for the diagnosis of infective endocarditis (IE), but its prognostic value remains unknown. OBJECTIVES This study sought to assess the prognostic value of 18F-FDG PET/CT in prosthetic valve endocarditis (PVE) and native valve endocarditis (NVE). METHODS This study prospectively included 173 consecutive patients (109 PVE and 64 NVE) with definite left-sided IE who had an 18F-FDG PET/CT and were followed-up for 1 year. The primary endpoint was a composite of major cardiac events: death, recurrence of IE, acute cardiac failure, nonscheduled hospitalization for cardiovascular indication, and new embolic event. RESULTS 18F-FDG PET/CT was positive in 100 (58%) patients, 83% (n = 90 of 109) in the PVE, and 16% (n = 10 of 64) in the NVE group. At a mean follow-up of 225 days (interquartile range: 199 to 251 days), the primary endpoint occurred in 94 (54%) patients: 63 (58%) in the PVE group and 31 (48%) in the NVE group. In the PVE group, positive 18F-FDG PET/CT was significantly associated with a higher rate of primary endpoint (hazard ratio [HR]: 2.7; 95% confidence interval [CI]: 1.1 to 6.7; p = 0.04). Moderate to intense 18F-FDG valvular uptake was also associated with worse outcome (HR: 2.3; 95% CI: 1.3 to 4.5; p = 0.03) and to new embolic events in PVE (HR: 7.5; 95% CI: 1.24 to 45.2; p = 0.03) and in NVE (HR: 8.8; 95% CI: 1.1 to 69.5; p = 0.02). In the NVE group, 18F-FDG PET/CT was not associated with occurrence of the primary endpoint CONCLUSIONS: In addition to its good diagnostic performance, 18F-FDG PET/CT is predictive of major cardiac events in PVE and new embolic events within the first year following IE.