Silent myocarditis in systemic sclerosis detected by cardiovascular magnetic resonance using Lake Louise criteria

BACKGROUND Systemic sclerosis (SSc) is an autoimmune disease characterized by microvascular abnormalities, inflammation and fibrosis. We hypothesized that myocarditis may be diagnosed in asymptomatic SSc, undergoing routine cardio-vascular magnetic resonance (CMR) for fibrosis assessment, using the Lake Louise criteria: T2 ratio, early (EGE) and late gadolinium enhanced (LGE) images. METHODS Eighty-two asymptomatic SSc, diagnosed according to American College of Rheumatology criteria, aged 43 ± 5 yrs., 62 with diffuse (dSSc) and 20 with localized (lSSc) systemic sclerosis were evaluated by CMR, performed at 1.5 T scanner, according to Lake Louise criteria. RESULTS CMR documented normal biventricular function in all SSc. However, 7/62 (11.2%) with dSSc and 2/20 (10%) with lSSc, had CMR signs of myocarditis according to Lake Louise criteria, without any clinical cardiac symptom. In these 9 patients, T2 ratio, EGE ratio and LGE (positive in all 9 SSc) were 2.8 ± 0.5%, 8 ± 3% and 5 ± 3% of LV mass, respectively. No correlation between CMR and blood inflammatory indices (C-reactive protein and erythrocyte sedimentation rate), cardiac troponin T, disease characteristics or type of SSc was identified. A repeat CMR at 6 months, after treatment with prednisone and azathioprine, showed normalisation of the acute inflammation CMR indices. CONCLUSIONS Silent myocarditis may be diagnosed using the Lake Louise paper criteria in SSc patients without cardiac symptoms, has no correlation with blood inflammatory indices, cardiac troponin or disease characteristics. CMR is a promising tool to diagnose silent myocarditis in SSc and monitor the response to immunosuppressive treatment.