A Young Male with Severe Myocarditis and Skeletal Muscle Myositis

Abstract

A 34-year-old male presented with retrosternal chest pain, fatigue, shortness of breath, and a history of a previous episode of myocarditis four years prior. He had elevated troponin T, normal skeletal muscle enzymes, and negative inflammatory markers. Cardiac magnetic resonance imaging (MRI) confirmed active myocarditis with extensive myocardial fibrosis and normal left ventricular ejection fraction (LVEF). His myocarditis symptoms resolved with steroids and anti-inflammatory treatment, but on closer questioning, he reported a vague history of long-standing calf discomfort associated with episodes of stiffness, fatigue, and flu-like symptoms. MRI of the lower legs consequently demonstrated active myositis in the calf muscles. Immunomodulatory therapy was commenced with good effect. The patient is undergoing regular follow-up in both cardiology and rheumatology outpatient departments. Repeated MRI of the legs showed significant interval improvement in his skeletal muscle myositis, and repeat cardiac MRI demonstrated the resolution of myocarditis along with persistent stable extensive myocardial fibrosis and preserved LVEF. The patient has returned to full-time work.

Update on myocarditis – what we know so far and where we may be heading

“…94 Since myocarditis typically presents as a systemic illness that may also affect skeletal muscle, it is plausible that more severe acute myocarditis may be associated with the release of myoglobin from skeletal muscle, which could contribute to higher blood levels of the markers. 95,96 Highly elevated cardiac markers and enzymes may help to rule in acute cases, but absence of them does Table 2. Diagnostic criteria for clinically suspected myocarditis.…”

Myopericarditis and myositis in a patient with COVID-19: a case report

“…Concomitant myopericarditis and myositis is most commonly associated with endemic cardiotropic viruses, 1 multisystem inflammatory diseases, 2–5 immunotherapy 6–8 and can occur idiopathically. 9 Whilst a single case report has described this association in seasonal influenza, 10 this has not been described in association with COVID-19. Here we describe the first documented case of a patient presenting with myopericarditis and myositis, associated with COVID-19.…”

Managing myocarditis in a patient with newly diagnosed dermatomyositis

“…A literature review of cardiac involvement in IIM by Gupta et al in 2011 found myocarditis as the most common feature (38%) in reported pathology literature 3. In a case report from 2018, a young man was described with a history of myocarditis who presented with symptoms of myocarditis and where further history and investigation demonstrated active myositis 4. Immunomodulatory therapy improved both his skeletal myositis and myocarditis.…”