Comparison of cardiac magnetic resonance imaging and fluorodeoxyglucose positron emission tomography in the assessment of cardiac sarcoidosis: Meta-analysis and systematic review

Aim: Fluorine-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) and cardiac magnetic resonance (CMR) are frequently used advanced cardiac imaging to diagnose cardiac sarcoidosis (CS). We conducted a meta-analysis and systematic review to compare diagnostic parameters of FDG-PET and CMR in the diagnosis of cardiac sarcoidosis (CS).

Methods: We searched PubMed, EMBASE, and Scopus databases from their inception to 9/30/2021 with search terms "cardiac sarcoidosis" AND "cardiac magnetic resonance imaging" AND "positronemission tomography". We extracted patient characteristics, results of the FDG-PET and CMR, and adverse outcomes from the included studies. Adverse outcomes served as a reference standard for the evaluation of FDG-PET and CMR.

Results: We included 4 studies in the meta-analysis which provided adverse outcomes and all patients underwent FDG-PET and CMR. There were 237 patients, 60.3% male, and ages ranged from 50-53 years. There were 45 events in 237 patients from four studies included in the meta-analyses. The pooled sensitivity (95% confidence interval-CI) and specificity (CI) of CMR in predicting an adverse event were 0.94 (0.79-0.98) and 0.49 (0.40-0.59), respectively. The pooled sensitivity (CI) and specificity (CI) of FDG-PET in predicting an adverse event were 0.51 (0.26-0.75) and 0.60 (0.35-0.81), respectively.

Conclusion: CMR was more sensitive but less specific than FDG-PET in predicting adverse events; however, the study population and definition of a positive test need to be considered while interpreting the results.