Clinical Outcomes of Radiologic Relapse in Patients With Cardiac Sarcoidosis Under Immunosuppressive Therapies

Although nuclear imaging can detect cardiac involvement of cardiac sarcoidosis (CS), including subclinical states, little is known about the prevalence and outcomes of radiologic relapse under prednisolone (PSL) therapy. This study aimed to investigate the clinical characteristics and outcomes in patients with radiologic relapse. A total of 80 consecutive patients with CS whose disease activity on nuclear imaging decreased at least once after initiation of immunosuppressive therapy were identified through a retrospective chart review. Radiologic relapse of CS was diagnosed using ¹⁸F-fluoro-2-deoxyglucose positron emission tomography or gallium-67 scintigraphy. Composite adverse events were defined as at least 1 of the following: all-cause death, hospitalization for heart failure, or lethal arrhythmia. During the follow-up period (median 2.9 years), radiologic relapse was observed in 31 patients (38.8% of overall patients) at 30 months (median) after immunosuppressive therapy initiation. After radiologic relapse was detected, all patients were treated with intensified immunosuppressive therapies (increasing PSL, n = 26 [83.9%], adding other immunosuppressive therapies to PSL, n = 5 [16.1%]). There were no differences in occurrences of composite adverse events in patients with and patients without radiologic relapse. Radiologic relapse under immunosuppressive therapy was observed in many patients with CS, but it was not associated with clinical outcomes under intensified immunosuppressive therapy.