Myocarditis and pericarditis following mRNA vaccination in autoimmune inflammatory rheumatic disease patients: A single‐center experience

INTRODUCTION: The mRNA vaccines Comirnaty (Pfizer/BioNTech) and Spikevax (Moderna) are considered safe and highly effective against SARS‐COV2. However, they are also associated with a small increased risk of pericarditis and myocarditis. There is concern about an increased risk of these complications in patients with autoimmune inflammatory rheumatic diseases (AIRD). CASE REPORT: We describe three patients with pre‐existing AIRD who developed myocarditis or pericarditis shortly after receiving their first dose of the Pfizer‐BioNTech vaccine. The first case is a 31‐year‐old female with systemic lupus erythematosus (SLE) and anti‐phospholipid syndrome (APLS) who presented 7 days after receiving the Pfizer‐BioNTech vaccine and was diagnosed with myopericarditis following a positive troponin and abnormal transthoracic echocardiogram (TTE). The second case is a 29‐year‐old man with seronegative inflammatory arthritis and APLS who presented 7 days after receiving the first dose of the Pfizer‐BioNTech vaccine. His troponin and TTE were unremarkable however his ECG showed widespread ST elevation. Lastly, the third case is a 34‐year‐old man with Behcet's disease with a history of recurrent pericarditis. He developed a recurrence of symptoms approximately 7 days after his Pfizer‐BioNTech vaccine and self‐commenced prednisolone at home. He had normal laboratory and radiological findings. All patients received prednisolone resulting in a quick recovery and resolution of symptoms. DISCUSSION: In this review we discuss the association between myocarditis, pericarditis and mRNA COVID‐19 vaccines, those who are at greatest risk and current clinical considerations. We also discuss the possible increased risk in AIRD patients and the current research supporting this.