Effectiveness and safety of IL1 inhibition with anakinra in chronic refractory idiopathic myocarditis

Aim: The aim of this study was to evaluate the effectiveness and safety of the anti-IL-1 receptor anakinra in patients with chronic active myocarditis refractory to standard therapy. Methods and results: In this retrospective, observational study, we enrolled 6 patients with chronically active myocarditis treated with anakinra on-top-of standard treatment. Response to treatment was evaluated at different time points [disease onset (T0), anakinra beginning (T1), three months from anakinra beginning (T2), last available follow-up (T3)], and was assessed by variations in New York Heart Association (NYHA) functional class, laboratory tests [C-reactive protein (CRP), a high-sensitivity cardiac troponin T (cTnT), and Nt-proBNP], left ventricular ejection fraction (LVEF), and cardiac magnetic resonance (CMR) edema or late gadolinium enhancement. The number of premature ventricular complexes (PVCs) at 24-h EKG-recordings was considered in patients with arrhythmic manifestations. No differences were found between T0 and T1 in terms of CRP, Nt-ProBNP, and LVEF. Before anakinra beginning, all patients were still symptomatic. At T2, all patients were symptom-free, in NYHA class I. A significant decrease in CRP (p = 0.03) and a significant improvement in LVEF (p = 0.03) were observed. Sustained arrhythmic manifestations were found in 4 out of 6 patients. In this subgroup, anakinra showed effectiveness in reducing the arrhythmic burden. At T3, the improvement in laboratory values and cardiac function persisted. The arrhythmic burden remained abated. Conclusions: All patients had a rapid improvement in systemic inflammation, cardiac function, and arrhythmic burden with anti-IL1 therapy, indicating that anakinra may be an effective treatment in chronic active idiopathic myocarditis, refractory to standard treatment.