Native T1 and T2 mapping by CMR in lupus myocarditis: Disease recognition and response to treatment.

Background: Lupus myocarditis is likely more common than recognized clinically due to non-specific symptoms and lack of reliable non-invasive diagnostic tests. We investigated the role of native T1 and T2 in recognition of active myocardial inflammatory involvement in patients with systemic lupus erythematous (SLE).

Methods: 76 patients with clinically suspected lupus myocarditis (14 males, age: 44±16years) underwent quantitative tissue characterization with native T1 and T2 mapping. Normotensive healthy subjects taking no medication served as controls (n=46). Follow-up CMR studies were performed in a total of 35 subjects of which 14 patients received intensified anti-inflammatory treatment, as guided by SLE disease activity.

Results: Compared to controls SLE patients had higher inflammatory markers, LV mass, native T1 and T2 values, and reduced longitudinal strain (p<0.01). In patients with a positive troponin test (n=36; 46%), native T1 and T2 were significantly higher (p<0.01) with otherwise similar proportions of diffuse perimyocardial LGE (33%) and pericardial effusion (32%). Sixty-nine patients (83%) had an abnormal native T1, whereas 51 (71%) met diagnostic criteria for acute myocarditis. Follow-up CMRs revealed significantly greater reduction in native T1 and T2 values in patients with intensified anti-inflammatory treatment (p<0.001) with the greatest change observed within the first follow-up period and plateauing thereafter. Native T1 and T2 were significant predictors of treatment response.

Conclusions: Native T1 and T2 mapping support recognition of lupus myocarditis and reflect the response to anti-inflammatory treatment. Native T1 and T2 mapping may support an effective, noninvasive, radiation- and gadolinium contrast-free screening method for lupus myocarditis.