Association between serum total antioxidant status and coronary microvascular function in idiopathic dilated cardiomyopathy

Abstract

Background: Coronary microvascular impairment may cause myocardial ischemia and systolic dysfunction in patients with idiopathic dilated cardiomyopathy (IDC).

Patients and methods: The study included 41 patients with IDC and 33 healthy control subjects. Serum total antioxidant status (TAS), serum interleukin (IL)-6 levels, and tumor necrosis factor (TNF)-α levels were assayed and coronary flow reserve (CFR) was measured in all subjects via echocardiography.

Results: High-sensitivity C-reactive protein (hsCRP) levels were significantly higher in patients with IDC than in the control group (3.42 ± 2.14 vs. 1.91± 1.40, p = 0.001). Serum TAS was statistically lower in patients with IDC than in controls (1.23 ± 0.16 vs. 1.77 ± 0.12, p < 0.001). CFR was statistically and significantly lower in the IDC group (2.10 ± 0.39 vs. 3.09 ± 0.49, p < 0.001). The IDC group was subsequently subdivided into two groups according to CFR values, as CFR ≥ 2 and CFR < 2. HsCRP (4.30 ± 2.42 vs. 2.58 ± 1.42, p = 0.01), TNF-α (16.67 ± 8.08 vs. 10.97 ± 1.63, p = 0.01), and IL-6 (7.54 ± 6.16 vs. 3.14 ± 1.10, p = 0.05) values were significantly higher in the CFR < 2 group compared with the higher CFR group. TAS (1.3 ± 0.16 vs. 1.14 ± 0.10, p < 0.001) was significantly lower in the CFR < 2 group. CFR correlated significantly with hsCRP, TAS, red cell distribution width (RDW), IL-6, and TNF-α.

Conclusion: Plasma proinflammatory cytokine levels are increased in patients with IDC. CFR was impaired as a reflection of impaired coronary microvascular dysfunction in association with increasing plasma proinflammatory cytokine levels and hsCRP levels.