Association between Serum Total Antioxidant Status and Coronary Microvascular Functions in Patients with SLE

Mortality from cardiovascular disease has been found to be increased in patients with systemic lupus erythematosus (SLE). Coronary flow reserve (CFR) measurement is used both to assess epicardial coronary arteries and to examine the integrity of coronary microvascular circulation. Oxidative stress, enhancing modification of plasma lipids, is also associated with atherosclerotic events in lupus patients. Impairment of CFR and TAS has been shown to be an early manifestation of coronary atherosclerosis. Forty patients with SLE and 33 healthy volunteers were included in this study. Echocardiographic examination included left ventricular myocardial velocity measurements and coronary flow reserve (CFR) measurement. Serum total antioxidant status levels (TAS) also were measured using TAS kit. Lateral myocardial early peak velocity (Em) and lateral Em/Am ratio did not differ between the groups, but lateral myocardial atrial peak velocity (Am) was significantly higher in SLE group than the control group. Baseline coronary diastolic peak flow velocity (DPFV) of left anterior descending was similar in both the groups. However, hyperemic DPFV and CFR (2.50 ± 0.42 vs. 3.09 ± 0.45, P < 0.0001) were significantly lower in the SLE group than in the control group. CFR significantly and inversely correlated with CRP and significantly correlated with TAS. Subclinical coronary microvascular dysfunction can occur in SLE patients without traditional cardiovascular risk factors, probably associated with underlying inflammation and impairment of TAS.