In the present study, we assessed oxidative stress in patients with dilated cardiomyopathy of ischemic or idiopathic etiology. For this reason we measured whole blood reduced glutathione, erythrocyte superoxide dismutase, susceptibility of erythrocyte membranes and erythrocytes to peroxidation, and SH content of erythrocyte membranes in 12 patients (8 men and 4 women, ages 31 to 66 years) with idiopathic dilated cardiomyopathy, in 11 patients (8 men and 3 women, ages 32 to 65 years) with ischemic dilated cardiomyopathy, and in 21 healthy volunteers (12 men and 9 women, ages 25 to 67 years). There was no statistically significant difference between the two patient groups for the indicators studied (P >0.05). Blood glutathione, erythrocyte superoxide dismutase, and membrane SH content of both groups of patients was decreased compared with controls (P <0.05), whereas erythrocyte and membrane susceptibility to peroxidation were increased (P <0.05). We conclude that patients with idiopathic or ischemic dilated cardiomyopathy exhibit abnormalities of a range of markers of increased oxidative stress. These abnormalities may contribute to contractile dysfunction, increased incidence of fatal arrhythmias, and sudden death.

The heart cannot supply sufficient blood for tissue metabolic needs in patients with congestive heart failure. Hypoxia and organ hypoperfusion increase oxidative activity. It has been reported that free radicals are involved in the genesis of heart failure. The aim of this study was to assess the status of oxidative stress by simple measurements in patients with dilated cardiomyopathy of ischemic or idiopathic etiology. Eleven patients (8 M, 3 F, age range 32 to 65 years) with dilated cardiomyopathy of ischemic etiology and 12 patients (8 M, 4 F, age range 31 to 66 years) with dilated cardiomyopathy of idiopathic etiology were included in the study. A control group included 21 healthy subjects (12 M, 9 F, age range 25 to 67 years). Levels of thiobarbituric acid-reactive substances, total thiols, and fluorescent products of lipid peroxidation were measured in plasma/serum samples of patients and controls. No statistically significant differences were found between the two patient groups for the parameters studied (p>0.05). Levels of thiobarbituric acid-reactive substances and fluorescent products of lipid peroxidation were higher in both patient groups than in controls (p<0.05), whereas concentrations of total thiols were decreased (p<0.05). In conclusion, in patients with idiopathic or ischemic dilated cardiomyopathy, there are associated abnormalities of a range of markers of increased oxidative stress and lipid peroxidation. The plasma/serum constituents studied can be routinely measured in order to monitor patients during antioxidant therapy.

In this study, evidence of decreased antioxidant status was determined in CMP patients together with vascular inflammation. CoQ10, other plasma antioxidants and hs-CRP measured routinely can reflect decreased antioxidant status and inflammatory process in patients with dilated CMP. These markers can be used to monitor the status of patients with CMP.