Prognosis of Myocardial Damage in Sarcoidosis Patients With Preserved Left Ventricular Ejection Fraction

Sarcoidosis is a systemic granulomatous inflammatory disease of unknown origin, in which myocardial involvement may be part of the systemic process or occur in isolation. The annual incidence of sarcoidosis in the United States has been estimated at 10.9 per 100 000 in whites and at 35.5 per 100 000 in blacks,1 and the prevalence of cardiac sarcoidosis (CS) in these patients ranges from 4% to 55%.2 This large range can, in part, be explained by patient selection criteria, different diagnostic methods, and different standards. Nevertheless, the main reason for the differences in the reported prevalence of CS is most likely the fact that the diagnosis of CS is challenging. Some patients may present with conduction abnormalities, ventricular arrhythmias, and symptoms of heart failure, pointing toward potential cardiac involvement of sarcoid disease. However, many patients present with nonspecific symptoms, no relevant ECG abnormalities, and preserved left ventricular ejection fraction (LVEF). Hence, ECG and echocardiography as criteria for CS in these patients might be misleading. Thus, there is a need for a reliable diagnostic tool to identify patients with CS. Cardiovascular magnetic resonance (CMR) as a noninvasive imaging technique delineates both functional and morphological aspects of the heart and, at the same time, provides excellent tissue characterization. One previous study comprising 81 consecutive patients with biopsy-proven extracardiac sarcoidosis and preserved LVEF compared cardiac involvement by late gadolinium enhancement (LGE) CMR with standard clinical evaluation using the consensus criteria (modified Japanese Ministry of Health guidelines 19933). LGE identified CS in 21 patients (26%) compared with 10 (12%; 8 overlapping) using Japanese Ministry of Health criteria resulting in a 2-fold higher rate for LGE. Pathology evaluation in 15 patients (19%) identified 4 with CS; all 4 were positive by LGE-CMR, whereas only 2 of them were positive by the Japanese Ministry of …