Coronary flow reserve is impaired in subclinical hypothyroidism.

Objective: Although the cardiovascular system is highly sensitive to thyroid hormones, the cardiovascular effects of subtle thyroid dysfunction such as subclinical hypothyroidism (SHT) remain unclear. Therefore, we investigated coronary flow reserve (CFR) reflecting coronary microvascular function in patients with SHT.

Methods: Fifty subjects with SHT and 30 control subjects with normal serum thyroid hormones and TSH levels were included in this study.

Association between serum gamma-glutamyltransferase levels and coronary microvascular function in hypertensive patients.

Objective: Serum gamma-glutamyltransferase (GGT) level is an independent risk factor for cardiovascular (CV) disease, and there is a strong association between serum GGT levels and most CV risk factors, including hypertension; however, the role of serum GGT level as an independent risk factor for target organ damage in hypertension remains controversial. Accordingly, we aimed to determine whether serum GGT level is independently and specifically associated with coronary flow reserve (CFR) impairment in hypertensive patients.

Methods: We examined 100 never-treated and newly diagnosed hypertensive individuals, and CFR was achieved in 97 (97%) of them.

Effects of normal blood pressure, prehypertension and hypertension on left ventricular diastolic function and aortic elastic properties.

Background: The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (BP) provides guideline for the new category of BP levels as normal, prehypertension (PHT), and hypertension. Although PHT is associated with a markedly increased risk of developing hypertension within 4 years, its prognostic significance and predisposition to target-organ damage is unknown. Accordingly, we evaluated the effects of normal BP, PHT and hypertension on left ventricular (LV) diastolic function and aortic elasticity, which are sensitive indicators of target-organ damage.

Nebivolol improves coronary flow reserve in patients with idiopathic dilated cardiomyopathy.

Background: Impaired coronary flow reserve (CFR) is a significant predictor of poor prognosis in patients with idiopathic dilated cardiomyopathy (IDC). Nebivolol reduces mortality and morbidity in patients with heart failure and left ventricular dysfunction, including cases caused by IDC.

Objective: To assess the effects of nebivolol on CFR in patients with IDC.

The influence of circadian blood pressure changes on aortic distensibility and left ventricular diastolic function in hypertensive individuals.

Background: Failure to decrease blood pressure (BP) normally during nighttime, which is called non-dipper, in hypertensive individuals is associated with higher cardiovascular morbidity and mortality. In addition, non-dipper BP leads to structural changes in the left ventricle; however, the influences of non-dipper BP on aortic elastic properties and left ventricular diastolic function have not been studied yet.

Methods: In this study, we evaluated aortic elastic properties and left ventricular diastolic function of 22 subjects with non-dipper hypertension, and 15 subjects with dipper hypertension using transthoracic second harmonic standard and tissue Doppler echocardiography (Acuson Sequoia C256).

Low serum bilirubin levels are independently and inversely related to impaired flow-mediated vasodilation and increased carotid intima-media thickness in both men and women.

Background: Elevated levels of low-density lipoprotein (LDL) cholesterol and its oxidative modification have been described to be involved in the process of atherogenesis. Bilirubin, an antioxidant, prevents oxidative modification of LDL and therefore may protect from atherosclerosis and coronary heart disease (CHD). Impaired brachial artery flow-mediated dilatation (FMD), which means endothelial dysfunction (ED) and carotid intima-media thickness (IMT) are predictors for the development and progression of atherosclerosis.