ABSTRACT
This aim of this study was to evaluate the presence of endothelial dysfunction in patients with primary hypertension and to determine the usefulness of nebivolol, a selective beta-adrenoceptor blocking agent, as a potential treatment for endothelial dysfunction. Of 176 patients with stage I hypertension, 36 patients (20%), the majority of whom were overweight/obese, were found to have abnormal results with myocardial perfusion single-photon emission computed tomography (MP-SPECT) under cold pressor test conditions. These 36 patients were treated for 28 days with 5 mg/d nebivolol, after which only 3 (8.3%) still had abnormal MP-SPECT results. The mean ischemia score was consistent with moderate risk and decreased significantly after treatment with nebivolol. All hemodynamic variables measured (systolic and diastolic blood pressure and heart rate) were also reduced significantly by treatment with nebivolol. Endothelial dysfunction plays a key role in the pathogenesis of atherosclerosis and its reversal has considerable implications for clinical outcomes in affected patients. The cold pressor testing results of this study suggest that nebivolol may have beneficial anti-ischemic effects in the coronary arteries of patients with hypertension. However, these findings need to be confirmed in larger randomized controlled trials, ideally comparing nebivolol with other blood pressure lowering agents or NO synthase inhibitors.
