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The aim of this study was to evaluate the distribution of resting heart rate and its biological and environmental determinants in adolescents. The study was crosssectional and the population consisted of 2230 children and adolescents, age range 12-18 years, enrolled randomly from state schools in Turin, Italy. In all participants the following parameters were evaluated: heart rate, blood pressure (BP), weight, height, degree of sexual development, physical activity, parental socio-cultural level. Heart rate and BP were measured after 5, 10 and 15 min in a sitting position. Furthermore, to obtain regression equations to define heart rate as a function of the other variables available, a multiple regression analysis was performed. In both sexes BP, but not heart rate, declined significantly from the first to the last determination. Heart rate was positively and significantly correlated to BP level in both sexes; heart rate was higher in girls (3 bpm) and followed a progressive decreasing trend with age in both sexes, that was opposite to BP values. Age, sexual maturation, height, physical activity and parental socio-cultural level were independent determinants of resting heart rate. In conclusion, resting heart rate in adolescents is related to several methodological, constitutional and environmental factors that have to be taken into account when assessing heart rate values and constructing tables of normal values. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated that essential hypertension is accompanied by sympathetic activation, which contributes to blood pressure elevation. Sympathetic activation also has adverse consequences in hypertensive patients beyond initiating blood pressure elevation. There is evidence that neural vasoconstriction has metabolic effects in skeletal muscle, impairing glucose delivery to muscles. In the liver, retarding of post prandial clearance of lipids contributes to hyperlipidemia. Cardiac sympathetic activation is a probable cause of sudden death in hearth failure. Atrophic effect of sympathetic activation on cardiovascular growth is also likely, contributing to the development of left ventricular hypertrophy. Consequently, one of the major aims of antihypertensive therapy should be to attenuate sympathetic tone. It is possible that, among the antihypertensive drugs available, those inhibiting the sympathetic nervous system might best reduce cardiovascular risk. [ABSTRACT FROM AUTHOR]

Objective: Antihypertensive agents of different classes may have profound effects on heart rate variability (HRV). HRV changes in patients with essential hypertension were evaluated after pharmacological treatment by time domain (TD) analysis on 24-hour electrocardiographic (ECG) recordings. Design and Patients: In this randomised block single-blind trial, 45 patients with essential hypertension were randomly assigned to either atenolol, a cardioselective β-blocker, carvedilol, a β-blocker with vasodilator properties, or lacidipine, a long-acting dihydropyridine calcium antagonist, and underwent simultaneous 24-hour ECG and ambulatory blood pressure monitoring before and after 8 weeks' treatment. TD measures were calculated. Results: During treatment with atenolol and carvedilol, the 24-hour average normal RR [mean normal to normal intervals (NN)] was significantly increased (p < 0.0001 and p < 0.0002, respectively). Measures of tonic vagal activity were increased significantly only with atenolol: increase of 64.3% for the percentage of differences >50msec between adjacent NN intervals and increase of 45.2% for root mean square successive differences. By contrast, standard deviations (SD) of all NN over a 24-hour period and SD of means of 5-minute blocks of NN related to total and diurnal HRV were significantly increased by lacidipine (13.4 and 18.9%, respectively) and decreased by carvedilol (-12.0% and -22.0%, respectively) but not significantly modified by atenolol. Modifications in TD parameters were unrelated to the degree of 24-hour blood pressure reduction. Conclusions: HRV, assessed by TD, is modified differently according to the specific type of antihypertensive monotherapy used. These modifications could have prognostic importance. TD measures of HRV may be a practical and powerful instrument for the evaluation of the effect of antihypertensive drugs. [ABSTRACT FROM AUTHOR]

Different types of statistical methods have been used for circadian blood pressure (BP) rhythm analysis in secondary forms of hypertension. In the present study, we used the two-step statistical approach by Fourier analysis with four harmonics for the parametrization of the diurnal BP pattern in secondary hypertension. In 43 essential hypertensives (EH), eight patients with aldosterone producing adenoma (APA), 25 with idiopathic hyperaldosteronism (IHA), four with glucocorticoid remediable hyperaldosteronism (GRH) and seven with renovascular hypertension (RVH), 24-h ambulatory BP was measured. The diurnal BP and heart rate (HR) rhythm was present in more than 70% of patients with secondary hypertension, without significant differences with EH and despite the attenuation in the degree of the nocturnal BP fall. In conclusion, the statement that secondary hypertension is characterized by an abnormal diurnal rhythm of BP is a gross over-simplification. Our findings suggest that the two-step method with four harmonics Fourier analysis may represent a useful method and a more complete statistical approach to providing circadian parametrization of the 24-h profile in secondary hypertension. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article about the characteristics of the patients reffered to a hypertension unit published in the September 13, 2007 issue of "Journal of human Hypertension."

A letter to the editor is presented in response to the article "How to simplify the diagnostic criteria of hypertension in adolescents," by Q. Lu and colleagues in the 2011 issue.

Background Renal sympathetic denervation (RDN) is indicated for the treatment of resistant hypertension (RH). The RH is true when the causes of pseudo-hypertension as well as other modifiable causes, e. g secondary hypertension or poor adherence, are excluded. In the clinical practice there are patients who due to polyintolerances or allergies can't be treated with the maximal therapy and therefore are not considered as RH – patients in accordance with the current definition. Since they are also very difficult to treat with medical therapy we also considered them in this study as eligible for renal denervation. The goal of the study is to assess the percentage of eligibility to RDN and analyze the exclusion criteria in a group of resistant hypertensive patients. Methods Between 2011 and 2014 we retrospectively reviewed patients who came to our Center for an evaluation for RDN. We considered patients with office blood pressure ≥160 mmHg and patients with severe hypertension treated with fewer drugs because of poly-intolerances / allergies as eligible. At first a specialist optimized drug therapy and subsequently reassessed the blood pressure response. For each patient a diagnostic examination was conducted in order to rule out secondary hypertension. To exclude a white coat effect the patients each performed an arterial blood pressure monitoring (ABPM). In patients with true resistant hypertension, a CT angiography was performed in order to check the renal anatomic criteria of eligibility to the RDN. Results Out of the 35 participating patients, 27 were considered unsuitable for the RDN for at least one of these causes: blood pressure control with optimization of drug therapy (52%), evidence of white coat effect (22%), secondary hypertension (22%), lack of true resistant hypertension (18%), absence of consent to the procedure (29%). All eight eligible patients were sent by specialist centers while the major part of the unsuitable patients was sent by GPs. Conclusions Before giving the indication for RDN, it is necessary to carefully select patients with RH as most of the patients proved ineligible due to inadequacy of drug therapy and white coat hypertension. [ABSTRACT FROM AUTHOR]

A prolongation of QT interval increases the risk for coronary heart disease, ventricular arrhythmias, and sudden death in diabetic patients, after myocardial infarction, and in the elderly. An association between QT prolongation and cardiovascular risk factors has been demonstrated in middle-aged and elderly subjects. Aims of this study were to evaluate the prevalence of a prolonged corrected QT interval (QTc) in a healthy young population (n=170, age 22–25 years, 84 males) and to investigate the association of QTc and QT dispersion (QTd) with cardiovascular risk factors (body mass index, blood pressure, fasting blood glucose and cholesterol, smoking habits, and hypertensive familiarity). A prolonged QTc was observed in 10% of female and 5% of male subjects; in multiple regression analysis, QTc showed a significant positive relationship with blood glucose in females (P=0.04) and systolic blood pressure in male subjects (P=0.03), while QTd was not significantly related with any of the factors. In conclusion, the association between QTc length, glucose levels, and blood pressure is present also in young healthy subjects. QT measurement may represent a useful marker in the screening of young subjects for cardiovascular prevention.Journal of Human Hypertension (2005) 19, 623–627. doi:10.1038/sj.jhh.1001874; published online 19 May 2005 [ABSTRACT FROM AUTHOR]

The resistant hypertension has been differentiated in true resistant hypertension and white-coat resistant hypertension by using ambulatory blood pressure monitoring. White-coat resistant hypertension was defined as high clinic blood pressure, despite triple treatment for at least 3 months, but day-time blood pressure values < 135/85 mmHg. The aim of this study was to evaluate the presence of different clinical characteristics between two types of resistant hypertension. The study group consisted of 49 patients with essential hypertension, resistant to an adequate and appropriate triple-drug therapy, that included a diuretic, with all 3 drugs prescribed in near maximal doses and that had persistently elevated clinic blood pressure (> 140/90 mm Hg), for at least 3 months. They represented the 2% of 2500 hypertensive outpatients that referred at our Hypertension Unit. Patients with white-coat resistant hypertension (n=19) were older (p<0.05) than those with true resistant hypertension (n=30). The sodium intake (p<0.05) and alcohol intake (p<0.05) were significantly higher in patients with true resistant hypertension than in those with white-coat resistant hypertension. The renin plasma activity and plasma aldosterone were higher (p<0.05) in patients with true resistant hypertension than in those with white-coat resistant hypertension with normal plasma electrolyte balance. There were no significant differences in mean values of office systolic and diastolic blood pressures between white coat resistant hypertensives and true resistant hypertensives ( 165+17 vs 172+28 and 98+12 vs 102+14 mmHg ). Day-time and night-time ambulatory 24-h-systolic and diastolic blood pressures were significantly higher in the true resistant hypertensive patients when compared with white-coat resistant hypertensives (153+15 vs 124+10 mmHg and 97+9 vs 76+6 mmHg all p<0.001). Day-time and night-time ambulatory 24-h-heart rate were significantly higher in the true resistant... [ABSTRACT FROM AUTHOR]

A deranged baroreceptor control of the cardiovascular functions has been reported in essential hypertension. Studies performed in experimental animals and in humans using different approaches have documented an impairment of both baroreflex heart rate modulation (resetting and loss of sensitivity) and baroreceptor control of peripheral vasomotor tone (only resetting). Baroreflex alterations have been reported also in secondary forms of hypertension, but data are controversial. This paper reviews recent works concerning baroreflex function in secondary hypertension. Either structural changes of arterial wall (decrease of vascular distensibility) or functional processes (involving angiotensin II, aldosterone, catecholamines, nitric oxide) have been proposed as potential mechanisms responsible for baroreflex readjustments in secondary hypertension. It remains unclear, and it is difficult to define exactly, if baroreflex changes associated with secondary form of hypertension are primarily due to factors specific for different hypertensive conditions, or merely follow blood pressure elevation. [ABSTRACT FROM AUTHOR]

Hypertension and obesity are risk factors for coronary heart diseases in adults. In turn, childhood overweight and high blood pressure increase the risk of subsequent obesity and hypertension in adulthood. Human obesity is characterized by profound alterations of hemodynamic and metabolic states. Whether these alterations involve sympathetic nervous system control on cardiac function is controversial. We report the results of our study, conducted in a sample of obese adolescents by using power spectral analysis of heart rate variability. An increase in sympathetic tone coupled with a reduction in vagal tone was found. This allowed us to hypothesize that autonomic nervous system changes depend on the time course of obesity development. It is still unclear if treatment of obesity in adolescence prevents subsequent autonomic imbalance and hypertension. [ABSTRACT FROM AUTHOR]

Renin-angiotensin-aldosterone system (RAAS) is recognized as the main regulatory system of hemodynamics in man, and its derangements have a key role in the development and maintenance of arterial hypertension. Classification of the hypertensive states according to different patterns of renin and aldosterone levels ("RAAS profiling") allows the diagnosis of specific forms of secondary hypertension and may identify distinct hemodynamic subsets in essential hypertension. In this review, we summarize the application of RAAS profiling for the diagnostic assessment of hypertensive patients and discuss how the pathophysiological framework provided by RAAS profiling may guide therapeutic decision-making, especially in the context of uncontrolled hypertension not responding to multi-therapy. [ABSTRACT FROM AUTHOR]

Arterial hypertension is associated with an increased risk of atrial fibrillation (AF), and leads to a pronounced increase in morbidity and mortality. Left atrial volume (LAV) is an important prognostic marker in the older populations. The aim of our study was to identify the clinical and echocardiographic determinants of LAV in middle-aged (<70 years old) essential hypertensive patients.We evaluated cardiac structure and function in 458 patients, 394 treated and untreated mild to moderate essential hypertensives patients (mean±s.d. age 48.4±11.1 years) with no associated clinical condition and 64 normotensive control participants (age 45.7±12.8 years; P=0.12). A multivariate analysis was performed to calculate the relative weight of each of the variables considered able to predict LAV. The LAV index (LAVi) was significantly increased in the essential hypertensive group vs the control group and was significantly dependent on blood pressure levels (SBP and DBP, P<0.05 for both) and body mass index (BMI) (P<0.0001). Considering the left ventricular (LV) variables, the LV mass index (LVMI) (R2=0.19, P<0.001) and LAV were increased in essential hypertensive patients with left ventricular hypertrophy (LVH), and patients with enlarged LAV showed lower systolic and diastolic function and an increased LVMI. The LAVi is dependent on blood pressure levels and anthropometric variables (age and BMI). Further structural (LVMI) and functional (systolic and diastolic) variables are related to the LAVi; LVMI is the most important variable associated with LAV in mild to moderate essential hypertensive adult patients. These findings highlight the importance of left atrium evaluation in adult, relatively young, essential hypertensive patients. [ABSTRACT FROM AUTHOR]

Recently, much interest has focussed on the potential interaction between sympathetic nervous system and global cardiovascular risk. We investigated how baroreflex sensitivity (BRS), an index of autonomic function, interacts with central obesity (CO) in an essential hypertensive (EH) population. We selected 170 EHs and 43 normotensives (NT), (median age 47.3±11.3 and 49.1±13 years, respectively). Anthropometric parameters were measured for each and BRS was evaluated by a non-invasive method using Portapres TNO. The BRS evaluation was made using the sequences method. Systolic blood pressure (SBP) and heart rate were significantly higher in EH (P<0.001 and P=0.007, respectively). BRS was significantly greater in NT (P=0.02), and was associated inversely with waist circumference (WC) (P=0.005), but not with SBP or with other metabolic risk factors. Body mass index, total and high-density lipoprotein cholesterol, age and WC were not significantly different between the two groups. These results were confirmed by age pounded analysis. Finally, a separate analysis of the hypertensive group with CO (n=84) demonstrated a significantly lower BRS compared with the other hypertensive patients (n=86) (P<0.001). BRS is associated with WC but not with arterial pressure values and metabolic risk factors. Hypertensive subjects with CO show an impairment of BRS. Owing to its association with abdominal fat distribution and subsequently insulin resistance, BRS could represent a further and reliable index for evaluation of global cardiovascular risk in hypertensive patients.Journal of Human Hypertension (2007) 21, 473–478. doi:10.1038/sj.jhh.1002163; published online 8 February 2007 [ABSTRACT FROM AUTHOR]

Hypertension is a condition where adrenergic responsiveness, sympathetic activity and adrenoceptors are somewhat altered. Many techniques are available to assess human sympathetic nervous system activity. They each present limitations and disadvantages. Characterization and subdivision of the α and β-adrenoceptors, according to their localization and answer to different agonists, was facilitated in recent years by the extensive use of pharmacological and molecular biology techniques. Some adrenoceptor studies were conducted on animal models, human tissues and peripheral blood cells to assess their changes in various forms and stages of hypertension. Our group has pointed out that &alpha[SUB1]-adrenergic receptors expressed by human peripheral blood lymphocytes underwent changes of density in essential hypertensives, compared to normotensive control subjects. The importance of these findings could provide an assessment of α[SUB1]-peripheral receptors with possible future clinical implications in the pathophysiology and treatment of hypertension. [ABSTRACT FROM AUTHOR]

Autonomic nervous dysfunction, such as parasympathetic and sympathetic impairment, has been suggested as possible cause of pre-eclampsia, but the studies are not conclusive. Our purpose was to assess non-invasively if pre-eclampsia is associated with a decreased baroreflex function. Nine women with pre-eclampsia (PE), eight normotensive pregnant women, and seven healthy normotensive non-pregnant women were studied. Continuous finger blood pressure was recorded by a Portapres device in the left lateral recumbent position and active standing. Baroreflex gain was evaluated by cross-spectral analysis of systolic blood pressure and pulse interval. The result was that baroreflex gain at rest was lower in pre-eclamptic women both compared to non-pregnant and healthy pregnant subjects (P < 0.05). Moreover, a decrease of the baroreflex sensitivity was present in all pregnant women in the orthostatic position (P < 0.05). In conclusion pregnancy per se is associated with a decrease in the baroreflex control of the heart, whereas in pre-eclampsia, the baroreflex sensitivity is impaired further. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate if changes in vascular properties were related to baroreflex function in patients with primary aldosteronism. Twenty-three patients with primary aldosteronism, 22 essential hypertensive patients and 16 normal controls were studied. Continuous finger blood pressure (BP) was recorded by Portapres device during supine rest and active stand up. Compliance was estimated from the time constant of pressure decay during diastole. Baroreflex sensitivity was calculated by autoregressive cross-spectral analysis of systolic BP and interbeat interval. The result was that baroreflex gain and compliance were lower in primary aldosteronism patients in the supine position P = 0.002 and P < 0.05 respectively. Aldosterone plasma levels (R[SUP2] = 0.31, P = 0.01), age, systolic and diastolic BP, high and low frequency components of diastolic BP variability were independently related to compliance in primary aldosteronism. In conclusion primary aldosteronism is associated with an impaired baroreflex function related in part to a reduced arterial compliance. Despite a reduction of BP values and aldosterone levels, surgical or pharmacological treatment did not significantly change compliance values. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the differential response in left ventricular mass and resistive index (RI) of renal and carotid arteries in mild to moderate essential hypertensive patients after 1 year of ACE inhibitor therapy. Twenty-six patients (mean age 42.9 ± 10.9 years) underwent 24-hour ambulatory blood pressure monitoring, echocardiography and renal and carotid echo-Doppler (by measuring RI, as an expression of arterial impedance) after a placebo period and 12 months of fosinopril treatment (20 mg/day). Our study showed a significant decrease in 24-hour BP (p < 0.05), left cardiac mass (p < 0.05) and RI of common carotid and hilum renal arteries (p < 0.05). In contrast, there were no significant reductions in the interlobar renal RI (as an expression of unchanged intrarenal resistance) and in the internal carotid artery RI. While the 24-hour BP decrease was strongly correlated with the left cardiac mass modifications (r = 0.73, p < 0.005), no significant relationship was observed with the renal and carotid artery parameters. In conclusion, the present study demonstrated that long-term treatment with fosinopril produced a differential response in left ventricular mass and arterial RI in patients with mild to moderate essential hypertension. In addition, the arterial impedance modifications of common carotid and hilum renal artery were largely unrelated to the 24-hour BP reduction. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 78-year-old never-smoking Caucasian woman who demonstrated a 4-month history of persistent dry cough and episode severe dyspnoea along with inspiratory stridor and chest pain. The woman underwent a spirometric examination which indicated a moderate airway obstruction that was believed to be asthma. The patient was admitted to the hospital and was submitted to chest radiograph and laboratory investigations.