Diagnostic Value of 18F-Fluorodeoxyglucose Positron Emission Tomography Computed Tomography in Prosthetic Pulmonary Valve Infective Endocarditis

The aim of this study was to assess the diagnostic performances of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) in congenital heart disease (CHD) patients with pulmonary prosthetic valve or conduit endocarditis (PPVE) suspicion. PPVE is a major issue in the growing CHD population. Diagnosis is challenging, and usual imaging tools are not always efficient or validated in this specific population. Particularly, the diagnostic yield of 18F-FDG PET/CT remains poorly studied in PPVE. A retrospective multicenter study was conducted in 8 French tertiary centers. Children and adult CHD patients who underwent 18F-FDG PET/CT in the setting of PPVE suspicion between January 2010 and May 2020 were included. The cases were initially classified as definite, possible, or rejected PPVE regarding the modified Duke criteria and finally by the Endocarditis Team consensus. The result of 18F-FDG PET/CT had been compared with final diagnosis consensus used as gold-standard in our study. A total of 66 cases of PPVE suspicion involving 59 patients (median age 23 years, 73% men) were included. Sensitivity, specificity, positive predictive value, and negative predictive value of 18F-FDG PET/CT in PPVE suspicion were respectively: 79.1% (95% CI: 68.4%-91.4%), 72.7% (95% CI: 60.4%-85.0%), 91.9% (95% CI: 79.6%-100.0%), and 47.1% (95% CI: 34.8%-59.4%). 18F-FDG PET/CT findings would help to correctly reclassify 57% (4 of 7) of possible PPVE to definite PPVE. Using 18F-FDG PET/CT improves the diagnostic accuracy of the Duke criteria in CHD patients with suspected PPVE. Its high positive predictive value could be helpful in routine to shorten diagnosis and treatment delays and improve clinical outcomes.