Impact of corticosteroid use on the clinical response and prognosis in patients with cardiac sarcoidosis who underwent an upgrade to cardiac resynchronization therapy

Background Corticosteroids are widely used in patients with cardiac sarcoidosis (CS). In addition, upgrading to cardiac resynchronization therapy (CRT) is sometimes needed. This study aimed to investigate the impact of corticosteroid use on the clinical outcomes following CRT upgrades. Methods A total of 48 consecutive patients with non‐ischemic cardiomyopathies who underwent CRT upgrades were retrospectively reviewed and divided into three groups: group 1 included CS patients taking corticosteroids before the CRT upgrade (n = 7), group 2, CS patients not taking corticosteroids before the CRT upgrade (n = 10), and group 3, non‐CS patients (n = 31). The echocardiographic response, heart failure hospitalizations, and cardiovascular deaths were evaluated. Results The baseline characteristics during CRT upgrades exhibited no significant differences in the echocardiographic data between the three groups. After the CRT upgrade, responses regarding the ejection fraction (EF) and end‐systolic volume (ESV) were significantly lower in CS patients than non‐CS patients (ΔEF: group 1, 6.7% vs. group 2, 7.7% vs. group 3, 13.6%; p = .039, ΔESV: 3.0 ml vs. ‐12.7 ml vs. ‐37.2 ml; p = .008). The rate of an echocardiographic response was lowest in group 1 (29%). There were, however, no significant differences in the cumulative freedom from a composite outcome among the three groups (p = .19). No cardiovascular deaths occurred in group 1. Conclusion The echocardiographic response to an upgrade to CRT and the long‐term prognosis in patients with CS should be carefully evaluated because of the complex etiologies and impact of immunosuppressive therapy. The echocardiographic response to an upgrade to CRT was lower in patients with CS than in those with other etiologies of non‐ischemic cardiomyopathy. The patients with CS who had taken corticosteroids before the upgrade to CRT (group 1) demonstrated the lowest echocardiographic response. However, the cumulative freedom from hospitalizations from worsening heart failure and cardiovascular death did not significantly differ between patients with CS and those with other etiologies.