Background In addition to muscular weakness, patients with Idiopathic inflammatory myopathy (IIM) may presentasymtomatic myocardial damage and endothelial dysfunction. Malondialdehyde (MDA) is a product of lipid peroxidation that may cause endothelial activation and dysfunction, also it has been related to disease activity in patients with SLEand RA. Myocardial global strain is a useful method for the detection of impaired myocardial contractility in diseases thatcause microvascular damage such as diabetes mellitus, ischemic heart disease, SLE, RA and Antiphospholipidsyndrome. Neither, MDA and myocardial strain have been studied in patients with IIM.
Objectives To evaluate the presence of endothelial dysfunction and asymtomatic myocardiopathy in patients with IIM.
Methods Patients with diagnosis of IIM (Bohan and Peter), >16 yr old, without symptoms of heart failure were recluted and matched with healthy controls. We excluded patients with diagnosis of ischemic heart disease, valvulopathy, arrythmia, anemia, pregnancy, nefrotic or overlap syndrome. Medical charts were reviewed for demographic data, disease status and treatment. Measurement of serum levels of malondyaldehyde (MDA), brain natriuretic peptide (BNP), standard transthoracic ecochardiography with tisular doppler mode and strain imaging were performed to patients and controls. Descriptive statistics, Student’s t, χ2, Mann Whitney’s U and Spearman’s rho tests were used.
Results Eighteen patients, 15 (83%) dermatomyositis, 3 (17%) polimyositis and 18 controls were compared. Mean age 43 (±13.93) and 42 (±13.18).Body mass index was similar between groups (24.48 vs 24.23, p=0.981).The serum levels of BNP were normal.The control group had higher MDA serum levels than the IIM group (13.93±6.10 vs 8.53±3.27, p<0.001). We found a negative correlation between body weight and serum levels of MDA (rho: -0.747, p<0.001) and BNP levels (rho=-0.594, p=0.009) in IIM. Regardless of disease or control status, lower levels of MDA were associated to folic acid supplementation (p=0.002). Ventricular ejection fraction was normal. Diastolic dysfunction was prevalent in the IIM group (56%, p<0.01). Circunferential, longitudinal and radial global strain were significantly lower in IIM group (p<0.01).
Conclusions Adult patients with IIM have asymptomatic diastolic dysfunction and decreased global longitudinal strainvalues that may be caused by microvascular lession and/or myocardial inflammatory infiltrate. Echocardiographic evaluation should be used in the routine care of this patients. Longitudinal studies are necessary to stablish the prognosis and the need of treatment against myocardial remodeling in this group of patients.
Buss SJ, Wolf D, Korosoglou G, et al. Myocardial left ventricular dysfunction in patients with systemic lupuserythematosus: new insights from tissue Doppler and strain imaging. J Rheumatol. 2010 Jan;37(1):79-86.
Disclosure of Interest None Declared