Diagnosis and Management of Patients With Suspected Left-Sided Prosthetic Valve Endocarditis According to Cardiac FDG-PET CT Results.

BACKGROUND: Despite advances in echocardiography, the definitive diagnosis of prosthetic valve endocarditis (PVE) remains difficult. 18F-fluorodeoxyglucose (chemical name 2-deoxy-2-[18F]fluro-D-glucose) positron emission tomography (PET) shows promise with improved sensitivity. Our study explored the effects of PET findings on the diagnosis of PVE and patient management decisions. METHOD: Between 2016 and 2022, 140 patients underwent PET to evaluate suspected left-sided PVE, resulting in 93 patients with positive PET (+PET) and 47 patients with negative PET. Patients were classified as definite, possible, or rejected PVE according to the 2023 Duke-International Society for Cardiovascular Infectious Diseases guidelines, initially excluding and then including PET results. We evaluated the association between PET results and clinical outcomes such as duration of antibiotics, performance of cardiac surgery within 3 months, and long-term mortality. A qualitative analysis of medical decision-making was performed. RESULTS: Demographics were similar between groups. patients with +PET had higher C-reactive protein levels (9.8 vs 3.1 mg/L, P = .001) and were more likely to have positive blood culture and echocardiographic findings. The addition of PET significantly increased the diagnosis of definite endocarditis (46%-63%, P < .001). A +PET was positively associated with ongoing use of antibiotics after 3 months (odds ratio [OR] 3.93, P = .002) and surgical management (OR 5.99, P = .008). Based on qualitative review of medical decision-making, PET influenced management in 88 patients (63%), supporting longer duration of antibiotics in 22%, surgical management in 8.6%, and shorter duration of antibiotics in 11% of patients. CONCLUSIONS: Positron emission tomography results, when incorporated into multidisciplinary discussion, aided in a more definitive diagnosis of PVE and influenced management in the majority of patients.