Cardiac Abnormalities in Adult Patients With Polymyositis or Dermatomyositis as Assessed by Noninvasive Modalities

ObjectiveCardiac events are a major cause of death in patients with idiopathic inflammatory myopathies. The study objective was in a controlled setting to describe cardiac abnormalities by noninvasive methods in a cohort of patients with polymyositis (PM) or dermatomyositis (DM) and to identify predictors for cardiac dysfunction. MethodsIn a cross-sectional study, 76 patients with PM/DM and 48 matched healthy controls (HCs) were assessed by serum levels of cardiac troponin I, electrocardiography, Holter monitoring, echocardiography with tissue Doppler imaging, and quantitative cardiac Tc-99m-pyrophosphate (Tc-99m-PYP) scintigraphy. ResultsCompared to HCs, patients with PM/DM more frequently had left ventricular diastolic dysfunction (LVDD) (12% versus 0%; P=0.02) and longer QRS and QT intervals (P=0.007 and P < 0.0001, respectively). In multivariate analysis, factors associated with LVDD were age (P=0.001), disease duration (P=0.004), presence of myositis-specific or -associated autoantibodies (P=0.05), and high cardiac Tc-99m-PYP uptake (P=0.006). In multivariate analysis of the pooled data for patients and HCs, a diagnosis of PM/DM (P < 0.0001) was associated with LVDD. ConclusionPatients with PM or DM had an increased prevalence of cardiac abnormalities compared to HCs. LVDD was a common occurrence in PM/DM patients and correlated to disease duration. In addition, the association of LVDD with myositis-specific or -associated autoantibodies and high cardiac Tc-99m-PYP uptake supports the notion of underlying autoimmunity and myocardial inflammation in patients with PM/DM.