A Prospective Diagnostic Trial of Al[¹⁸F]F-NOTA-folate PET in Patients With Suspected Cardiac Sarcoidosis and Infective Endocarditis

The goal of this prospective diagnostic study is to evaluate the imaging characteristics, diagnostic performance, radiation dosimetry, and safety of Al\[¹⁸F\]F-NOTA-folate PET imaging in patients with suspected cardiac sarcoidosis and infective endocarditis, and healthy volunteers. The study is non-interventional with respect to clinical management, and all diagnostic and therapeutic decisions are made according to routine clinical practice independent of study participation. The main aims are to evaluate quantitative uptake of Al\[¹⁸F\]F-NOTA-folate measured by PET imaging in the left ventricular myocardium of patients with suspected cardiac sarcoidosis, and in cardiac valves or prosthetic valve regions in patients with suspected infective endocarditis. Participants will undergo PET imaging with Al\[¹⁸F\]F-NOTA-folate tracer at the Turku PET Centre. Participants with suspected cardiac sarcoidosis will undergo a second PET imaging study after initiation of immunosuppressive therapy.

Inclusion Criteria: * Ability to provide written informed consent * Suspected cardiac sarcoidosis group: clinical suspicion of cardiac sarcoidosis requiring diagnostic evaluation, including cardiac magnetic resonance and/or \[¹⁸F\]FDG PET * Suspected infective endocarditis group: clinical suspicion of native or prosthetic valve infective endocarditis requiring diagnostic evaluation * Healthy volunteers group: * Age above 50 and post-menopausal (women) * No history of cardiovascular disease, systemic inflammatory disease, malignancy, and no active infection Exclusion Criteria: * Pregnancy or breastfeeding * Known hypersensitivity to folate-based compounds or investigational medical product excipients * Unwillingness or inability to use effective contraception during the study participation period, in participants of childbearing potential * Severe renal impairment (CKD-EPI GFR \