Nutraceuticals and blood pressure control: a European Society of Hypertension position document.

: High-normal blood pressure (BP) is associated with an increased risk of cardiovascular disease, however the cost-benefit ratio of the use of antihypertensive treatment in these patients is not yet clear. Some dietary components and natural products seems to be able to significantly lower BP without significant side effects. The aim of this position document is to highlight which of these products have the most clinically significant antihypertensive action and wheter they could be suggested to patients with high-normal BP. Among foods, beetroot juice has the most covincing evidence of antihypertensive effect. Antioxidant-rich beverages (teas, coffee) could be considered. Among nutrients, magnesium, potassium and vitamin C supplements could improve BP. Among nonnutrient-nutraceuticals, soy isoflavones could be suggested in perimenopausal women, resveratrol in insulin-resistant patients, melatonin in study participants with night hypertension. In any case, the nutracutical approach has never to substitute the drug treatment, when needed.

L-NAME iontophoresis: a tool to assess NO-mediated vasoreactivity during thermal hyperemic vasodilation in humans.

BACKGROUND: Decreased endothelial Nitric oxide (NO) bioavailability is one of the earliest events of endothelial dysfunction. Assessment of microvascular blood flow using a Laser Doppler Imager during local noninvasive administration of L-N-Arginine-Methyl-Ester (L-NAME) by skin iontophoresis may help discriminate the relative contributions of NO and non-NO pathways during a skin thermal hyperemic test. METHODS: In healthy nonsmokers, the effects of thermal vasodilation and sodium nitroprusside-mediated vasodilation were tested on skin pretreated with 0.9% saline solution, 2% L-NAME iontophoresis (n = 12), or intradermal injection of 25 nmol L-NAME (n = 10). The effects of L-NAME iontophoresis were also measured in a group of smokers (n = 10). RESULTS: L-NAME iontophoresis and intradermal injection of L-NAME decreased the skin response to local heating to a similar degree (-41% ± 4% vs. -44% ± 6%). L-NAME iontophoresis site-to-site and day-to-day coefficients of correlation were 0.83 and 0.76, respectively (P < 0.01). The site-to-site and day-to-day coefficients of correlation of L-NAME injection were lower than those of iontophoresis at 0.66 (P < 0.05) and 0.12, respectively (P = not significant). Sodium nitroprusside-induced skin hyperemia was not affected by L-NAME administration. L-NAME iontophoresis-mediated inhibition of skin thermal hyperemia was greater in smokers than in nonsmokers (P < 0.05). CONCLUSIONS: Laser Doppler Imager assessment of skin thermal hyperemia after L-NAME iontophoresis provides a reproducible and selective bedside method of qualitatively analyzing the contribution of the NO pathway to microvascular vasomotor function.

Effects of right ventricular pacing on regional myocardial glucose metabolism.

AIMS: Permanent right ventricular apical pacing (RVP) is associated with a wide range of myocardial abnormalities. The purpose of this study was to determine the changes over time of RVP on myocardial blood flow (MBF) and glucose metabolism as assessed by positron emission tomography (PET). METHODS: In eight candidates for permanent pacemaker implantation PET imaging was performed with 13N-ammonia and 18F-Fluorodeoxyglucose (FDG) to assess MBF and glucose metabolism before (PET1) and repeated after 3 months of RVP (PET2). For the analysis, the left ventricle was divided into three parts (apex, mid-ventricular and base) and subdivided into six segments (inferior, posterior, lateral, anterior, antero-septal and infero-septal). RESULTS: After RVP, defects of FDG uptake were found in the left ventricle near the stimulation site, without corresponding changes in MBF. Changes over time in the mean FDG uptake were statistically significant between PET1 and PET2 in the apical inferior, apical-posterior, apical-anterior, apical antero-septal, apical infero-septal, mid-inferior and mid-infero-septal segments. CONCLUSIONS: This study shows that RVP induces major changes in the distribution of FDG uptake in the left ventricular myocardium. FDG uptake significantly decreases in the regions surrounding the pacing site.