Utility of updated diagnositc criteria to detect isolated cardiac sarcoidosis

Abstract

Abstract Background Prior study reported around one-third of cardiac sarcoidosis (CS) are considered as isolated CS. Detection of CS is challenging due to the limited sensitivity of endomyocardial biopsy and applicability of guidelines, especially in patients without extra-cardiac involvement. Existing diagnostic criteria by Japanese Ministry of health and Welfare (JMHW) or Heart Rhythm Society (HRS) require the presence of extra-cardiac sarcoidosis for clinical diagnosis, isolated CS is not diagnosable in the absence of a positive histological finding. Recently, Japanese Society of Cardiology (JCS) updated diagnostic criteria for CS, which provides the pathway to diagnose isolated CS. Purpose We aimed to assess the reliability of the updated CS guideline in diagnosing CS compared to the prior guidelines. Methods We retrospectively identified 162 consecutive patients who underwent FDG-PET for suspected CS from 2012 through 2019. According to the updated JCS diagnostic criteria, patients were classified as histologic diagnosis of CS, clinical diagnosis of CS, or isolated CS (Figure A). We compared the association between diagnostic criteria and response with anti-inflammatory therapy. Results The JCS criteria classified 24 patients (15%) as having clinical CS, 4 (3%) as histological diagnosis of CS, and 21 (13%) as isolated CS. The JMHW criteria defined 22 patients (14%) as having CS (clinical 11%, histological 3%) and HRS criteria classified 11 patients (7%) as having CS (clinical 4%, histological 3%). Extra-cardiac involvement was detected in 36 patients (22%) with 8% of histological confirmation. Among the 126 patients without extra-cardiac involvement, prevalence of cardiac involvement was higher in isolated CS (P<0.05 for all). Compared with clinical diagnosis group, patients with isolated CS showed higher incident of regional wall motion abnormality (WMA) or left ventricular (LV) dysfunction (p=0.023). In the subgroup of 45 patients with serial FDG-PET evaluation, only updated CS criteria was associate with improvement in myocardial inflammation by FDG-PET (p<0.001). Conclusions Updated JCS diagnostic criteria detects CS patients with active myocardial inflammation which require anti-inflammatory therapy regardless of extra-cardiac involvement better than the prior guidelines. Diagnostic criteria for CS Funding Acknowledgement Type of funding source: None