To the Editor:
The presence of cardiac insufficiency is recognized as a poor prognostic factor in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV)1, and heart failure is an identified mortality risk factor for eosinophilic granulomatosis with polyangiitis (EGPA)2. Microscopic polyangiitis (MPA) has lower frequencies of myocardial involvement with rarely reported acute myocarditis presentation3. Rituximab (RTX) is a first-line induction therapy licensed for severe MPA with reduced ANCA titers and clinical remission4. In this study, we reviewed hospitalized patients with MPA who were receiving RTX therapy for acute myocarditis-related heart failure.
A retrospective study was carried out at the National Cheng Kung University Hospital from January 2014 to December 2018. Hospitalized patients fulfilling the 2012 Revised Chapel Hill Consensus Conference MPA definition5 were analyzed under the permission of the institutional review board (approval no. B-ER-105-108). Acute myocarditis was defined as (1) symptoms such as fever, dyspnea, orthopnea, chest pain, and palpitation; (2) raised cardiac biomarker levels; and (3) new/worsening echocardiograph or cardiac magnetic resonance imaging (cMRI) changes including wall motion abnormalities and impaired left ventricular ejection fraction (LVEF) …
Address correspondence to Dr. C.R. Wang, Section of Rheumatology, Department of Internal Medicine, National Cheng Kung University Hospital, 138 Sheng-Li Road, Tainan 70428, Taiwan. E-mail: wangcr{at}mail.ncku.edu.tw