FRI0230 CLINICAL AND ECHOCARDIOGRAPHIC CHARACTERISTICS OF MYOCARDIAL INJURY IN SYSTEMIC LUPUS ERYTHEMATOSUS, CLASSIFIED ACCORDING TO CARDIAC MAGNETIC RESONANCECRITERIA

Abstract

Background: Lupus myocarditis (LM) occurs in 5-10% of patients with systemic lupus erythematosus (SLE). Subclinical myocardial inflammation occurs in 37% at post mortem.1 Echocardiographic strain (STE) supports subclinical myocardial dysfunction in SLE.2 Tissue characterisation by cardiac magnetic resonance (CMR) identifies myocardial inflammation, necrosis and/or fibrosis, detecting clinical and subclinical myocardial injury (MIN) in SLE. It‘s the non-invasive gold standard for diagnosing myocarditis (all types) based on the Lake Louise criteria (LLC).3 Objectives: Determine prevalence of MIN in SLE (LLC). Compare clinical and echocardiographic (echo) features of patients with and without MIN. Identify echo predictors of MIN. Methods: A prospective crossectional study was done at Tygerberg Hospital, Western Cape, South Africa. Adult inpatients, fulfilling the 2012 SLICC criteria were screened. Echo analyses included STE and regional function (wall motion score (WMS)). Patients were grouped according to evidence of MIN (absent criteria [AC]; single criterion [SAC]; fulfilling LLC), comparing clinical, laboratory and echo data. Logistic regression and ROC were used to determine predictors of MIN. Results: 49/106 SLE patients screened were included (Figure 1). 46.9% of patients had MIN (≥1 criterion): 12.2% fulfilled LLC for LM and 34.7% had a SAC. SLE disease activity (SLEDAI) (p=0.022) was higher in patients fulfilling LLC, but not in the SAC group. A clinical and echo diagnosis of LM was made in all patients fulfilling LLC, in 17.6% of patients in the SAC group and none in the AC group (Table 1). Anti-DsDNA and anti-B2GP1 were more frequently positive in SAC vs the AC group (p=0.054 and 0.081). WMS was higher in LLC and SAC groups (p=0.006;p=0.083) with mid and basal STE more impaired in patients with MIN (p=0.047;p=0.043). LVID and mid STE score combined was the best predictor of MIN (Table 2; Figure 2). Conclusion: CMR evidence of MIN is common in SLE, even in the absence of clinical myocardial dysfunction or high lupus activity. Impaired echo regional and global function occurs more frequently in patients with MIN. STE combined with LVID predicts MIN detected by CMR and has potential as a cost effective screening tool. CMR is limited by a high exclusion rate in SLE, mainly due to renal impairment.