The following is a summary of “Distinctive clinical traits of lupus-related myocarditis: a multicentre retrospective study,” published in the July 2024 issue of Rheumatology by Ramirez et al.

Cardiovascular issues are common in systemic lupus erythematosus (SLE), but distinct characteristics of SLE-related myocarditis (myoSLE) compared to patients with SLE (onlySLE) or myocarditis remain poorly understood.

Researchers conducted a retrospective study identifying distinctive traits of myoSLE compared to onlySLE and myocarditis alone.

They compared patients with myoSLE (n = 25) from 3 centers, with consecutive patients having onlySLE (n = 279) and onlyMyo (n = 88). Patients with SLE were categorized based on disease duration into recent (≤1 year) and longstanding (>1 year) groups, further divided into early myoSLE and late myoSLE, respectively. Additional stratification was carried out for disease durations of 1–5 years, 5–10 years, and >10 years. Disease activity was assessed using the SLE Disease Activity Index 2000 (SLEDAI-2K). Myocarditis diagnoses were confirmed via biopsy or magnetic resonance imaging (MRI).

The result showed that women were more commonly affected by myoSLE than onlyMyo (72% vs. 43%; P=0.013). Patients with myoSLE also had a higher incidence of conduction abnormalities (22% vs. 5%; P=0.046) and showed numerically higher rates of left ventricular dysfunction (48% vs. 30%), with elevated pro-brain natriuretic peptide levels. Inflammatory markers were increased in patients with myoSLE relative to onlyMyo and patients with onlySLE with over 10 years of disease duration. The SLEDAI-2K scores were significantly higher in late myoSLE compared to long-standing onlySLE. Antiphospholipid syndrome was more common in myoSLE compared to onlySLE. Multivariate analysis identified associations between myoSLE and anti-beta-2-glycoprotein I antibodies (aB2GPI, P=0.014) and a more significant number of involved British Isles Lupus Assessment Group domains (P=0.003).

Investigators concluded that myoSLE exhibited distinct clinical characteristics compared to other types of myocarditis and was linked to aB2GPI and a more severe course of SLE.

Source: academic.oup.com/rheumatology/advance-article/doi/10.1093/rheumatology/keae376/7719058