Clinical outcomes of patients with isolated cardiac sarcoidosis confirmed by clinical diagnostic criteria.

Abstract Background Although isolated cardiac sarcoidosis (CS) is not uncommon, little is known about the prognosis. We aimed to clarify clinical features and clinical outcomes in patients with isolated CS. Methods Two-hundred eighty-six patients with suspected CS were enrolled. Systemic CS (SCS) was diagnosed by histological or clinical confirmation of sarcoidosis according to the guidelines. Isolated CS was diagnosed by histological or clinical confirmation in the heart alone. The endpoint was cardiac death, hospitalization for heart failure, or fatal ventricular arrhythmia. Results Twenty-one patients were diagnosed with isolated CS, and 63 were diagnosed with SCS. The frequencies of diagnostic criteria, such as high-grade atrioventricular block or fatal ventricular arrhythmia, basal thinning of the ventricular septum, left ventricular contractile dysfunction, positive myocardial uptake of gallium-67 citrate scintigraphy or fluorine-18 fluorodeoxyglucose positron emission tomography, and delayed contrast enhancement of cardiac magnetic resonance, were higher or equivalent in patients with isolated CS, compared to those with SCS. Over a median follow-up of 31 months (range: 1–175 months), cardiac death, hospitalization for heart failure, or fatal ventricular arrhythmia occurred in 14 (67%) patients with isolated CS, 24 (38%) patients with SCS, and 63 (31%) patients without CS. The rate of cardiac events was higher in patients with isolated CS (log-rank test, p = 0.01). Cox proportional hazard analysis showed that isolated CS, age, and New York Heart Association functional class were independently associated with cardiac events. Conclusions Patients with isolated CS have clinical features compatible with SCS, and have cardiac events at a higher rate.