18-FDG PET/CT Imaging and Clinical Decisions in Infective Endocarditis

Introduction:

Infective endocarditis (IE) is a rare disease, often difficult to diagnose with a high mortality rate. Extra-cardiac manifestations, which can occur in 30 to 80% of cases, impact the outcome of the disease. Identifying these manifestations may help confirm an uncertain diagnosis and optimize patients' management.

18-FDG PET/CT imaging, widely used for cancer staging, may also detect hyper-metabolic areas related to extracardiac infectious complications of IE. It provides the opportunity to detect all extracardiac IE infectious complications through a single examination. The impact of 18-FDG PET/CT imaging on the management of IE has yet to be completely evaluated.

Hypothesis:

18-FDG PET/CT implementation could result in both shortening of the initial diagnostic work-up of IE and therapeutic optimization.

Primary objective:

To evaluate the impact of 18-FDG PET/CT on patients' management, as measured by changes in IE therapeutic plans.

Secondary objectives:

• To evaluate the impact of 18-FDG PET/CT on the Duke-Li criteria for IE diagnosis
• To evaluate the performance of 18-FDG PET/CT in detecting valve damages and extracardiac complications induced by the IE
• To evaluate whether 18-FDG PET/CT may help identify the infection's portal of entry
• To evaluate whether the detection of extracardiac complications by FDG PET/CT is associated with the 6-months survival rate
• To identify clinical and biological determinants of extracardiac IE localizations and prognosis
• To determine the inter-reader interpretation of the18-FDG PET/CT results and the reproducibility in preparation and acquisition method

Inclusion criteria

• Subjects aged ≥ 18 years
• Presenting IE "Duke-Li definite - Duke-Li possible" or strong suspicion of IE "Duke-Li not definite or possible, with initiation of IE antibiotic therapy".
• Transthoracic or transesophageal ultrasound performed.
• A stable clinical condition which does not require immediate surgery or contraindicate patient mobilization
• Absence of cardiac surgery for the current IE episode
• Covered by the French health insurance system
• Having given and signed the written study informed consent to the study.

Exclusion criteria

• Patient having already had a 18-FDG PET/CT in the current episode
• Contraindication to perform a 18-FDG PET/CT
• Early prosthetic valve IE (cardiac surgery within last 2 months)
• Inability to understand the information form
• Pregnant or lactating woman.
• Cardiac surgery between inclusion and 18-FDG PET/CT
• Participation to any clinical trial including 18-FDG PET/CT