Patients with systemic sclerosis (SSc) can have muscle involvement in the form of myositis or non-infl ammatory myopathy. The muscle involvement can be associated with left ventricular dysfunction (LVD) in patients with SSc, resulting in worse prognosis. Eighty-seven patients of the Hospital de Clínicas of the Universidade Federal do Paraná, diagnosed with SSc, were assessed regarding the presence of skeletal muscle manifestations and their relation with LVD. A 42.5% prevalence of muscle involvement was observed in the patients studied, as well as a positive correlation with the diffuse form of the disease. Excluding other causes of LVD, three of the four patients with ejection fraction below the normal reference value had alteration of the muscle strength, atrophy and/or serum creatine phosphokinase (CPK) elevation.