Beneficial effects of nebivolol treatment on oxidative stress parameters in patients with slow coronary flow

OBJECTIVES
Imbalance between oxidative stress and antioxidant defense has been demonstrated in patients with slow coronary flow (SCF). The aim of this study was to investigate the effect of nebivolol treatment on oxidative stress parameters in SCF patients.

STUDY DESIGN
The study included 32 patients (10 females, 22 males; mean age 53.3±5.2 years) with SCF and 32 control subjects (14 females, 18 males; mean age 50.6±5.2 years) with normal coronary arteries on angiography. Coronary slow flow was determined by the TIMI frame count method. Patients with SCF received nebivolol treatment (5 mg/day) for six months. Blood samples were analyzed for malondialdehyde (MDA) and serum nitric oxide (NO) levels, and erythrocyte catalase (CAT) and erythrocyte superoxide dismutase (SOD) activities in the control group and, in SCF patients, at baseline and after six months of nebivolol treatment.

RESULTS
The two groups were similar with respect to age, body mass index, blood pressure, heart rate, and lipid profile. Smoking was more frequent in the SCF group compared to the controls. TIMI frame counts measured from the left anterior descending, circumflex, and right coronary arteries were significantly higher in the SCF group (p<0.0001). Baseline MDA and NO levels, and SOD and CAT activities were significantly different between the two groups, with significantly increased MDA (p<0.0001), and significantly decreased SOD (p<0.0001), CAT (p<0.001), and NO (p<0.001) in the SCF group. After six months of nebivolol treatment, all oxidative stress parameters showed significant improvements compared to the baseline values (p<0.0001 for MDA, SOD, CAT, and NO) and approximated to the values of the control group.

CONCLUSION
Our results show that nebivolol treatment may be beneficial to improve oxidative stress parameters in patients with SCF, which is considered to be an early stage of atherosclerosis.