Can FDG PET Serve as a Clinically Relevant Tool for Detecting Active Non-sarcoidotic Myocarditis?

The diagnostic work-up for myocarditis largely depends on non-invasive imaging because of the low yield of endomyocardial biopsy. In addition, differentiation among possible impressions is essential because of its non-specific clinical presentations. This ambiguity has led to the predominant use of cardiac magnetic resonance imaging techniques in the management of myocarditis, particularly during the global pandemic. Despite the unique ability of F-18 fluorodeoxyglucose positron emission tomography to visualize and quantify active myocardial inflammation, which has been well established in cardiac sarcoidosis, its diagnostic contribution in non-sarcoidotic myocarditis remains uncertain. This article reviews the current evidence on the non-invasive imaging diagnosis of non-sarcoidotic myocarditis and discusses the potential role of F-18 fluorodeoxyglucose positron emission tomography as a clinically relevant imaging tool.