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Find video protocols related to scientific articles indexed in Pubmed.
The influence of illness severity on health satisfaction in patients with cardiovascular disease: the mediating role of illness perception and self-efficacy beliefs.
Behav Med
PUBLISHED: 12-17-2014
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The importance of psychological factors in improving conditions of cardiovascular disease (CVD) patients is stressed by the guidelines for their prevention and rehabilitation, but little is known about the impact of illness severity on patients' well-being, and on the psychosocial variables that may mediate this association. The aim of this study was to investigate the role of illness perception and self-efficacy beliefs on the relationship between illness severity and health satisfaction in 75 CVD patients undergoing rehabilitation (80% men; mean age = 65.44) at the St. Luca Hospital, Istituto Auxologico Italiano, Milan, Italy. Illness severity was measured in terms of left ventricular ejection fraction; psychological factors were assessed at the beginning and end of rehabilitation. Results from path analyses showed that the relationships among CVD severity and health satisfaction were mediated by illness perception and self-efficacy beliefs. Findings underscored the importance of considering illness representations and self-efficacy beliefs to improve well-being in CVD patients.
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Clinical and psychological telemonitoring and telecare of high risk heart failure patients.
J Telemed Telecare
PUBLISHED: 10-24-2014
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We conducted a trial of telemonitoring and telecare for patients with chronic heart failure leaving hospital after being treated for clinical instability. Eighty patients were randomized before hospital discharge to a usual care group (n?=?40: follow-up at the outpatient clinic) or to an integrated management group (n?=?40: patients learned to use a handheld PDA and kept in touch daily with the monitoring centre). At enrolment, the groups were similar for all clinical variables. At one-year follow-up, integrated management patients showed better adherence, reduced anxiety and depression, and lower NYHA class and plasma levels of BNP with respect to the usual care patients (e.g. NYHA class 2.1 vs 2.4, P?
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INSULIN RESISTANCE AND BEAT-TO-BEAT CARDIOVASCULAR DYNAMICS: A CONSTANT RELATIONSHIP ACROSS DIFFERENT BODY MASS INDEX AND BLOOD PRESSURE CATEGORIES.
J. Clin. Endocrinol. Metab.
PUBLISHED: 10-21-2014
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Context: Epidemiological studies have shown a progressive increase in insulin resistance accompanying body weight gain and blood pressure rise. This has led to consider that hemodynamic effects of insulin resistance might depend on its relationship with body mass index and blood pressure levels. Objective: Aim of our study was to determine whether insulin resistance is associated with changes in hemodynamic indices of cardiovascular function across different categories of body mass index (normal-weight, overweight, and obese), and blood pressure levels (normal blood pressure, high-normal blood pressure, and hypertension). Design, setting and participants: Cross sectional study conducted in a population sample of non-diabetic individuals (n=731). Measures: Insulin resistance was evaluated with the homeostasis model assessment of insulin resistance (HOMA) and subjects classified into quartiles according to HOMA index values. Synchronized beat-to-beat recordings of stroke volume (impedance cardiography) and R-R interval, along with repeated auscultatory blood pressure measurements were performed. Derived hemodynamic parameters were computed and averaged. Results: Analysis of covariance adjusting for confounders, showed significant differences for most hemodynamic parameters among different quartiles of HOMA index both in the general population and within each body mass index and blood pressure category. Overall, increasing values of HOMA index were associated with significantly higher BP levels; and reduced R-R interval, stroke index, cardiac index, pre-ejection period and left ventricular ejection time (p\h0.01) across different categories of body mass index and blood pressure. Conclusions: These findings indicate that even small increases in HOMA index (not necessarily in the range to define insulin resistance) may induce significant changes on indices of cardiovascular function even in normal weight and normotensive subjects, emphasizing the importance of insulin resistance at an early stage of the cardiovascular risk continuum.
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Evening versus morning dosing of antihypertensive drugs in hypertensive patients with sleep apnoea: a cross-over study.
J. Hypertens.
PUBLISHED: 10-17-2014
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:Beneficial effects of continuous positive airway pressure (CPAP) on both blood pressure (BP) levels and variability have been documented in patients with obstructive sleep apnoea (OSA). We investigated the relevant impact of different dosing times of antihypertensive drugs beyond CPAP application.
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Effect of long-term antihypertensive treatment on white-coat hypertension.
Hypertension
PUBLISHED: 09-22-2014
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Limited evidence is available on the extent and frequency by which antihypertensive treatment lowers office blood pressure (BP) in white-coat hypertension (WCH). Data are even more scanty and discrepant on the corresponding effect on ambulatory BP (ABP). In the hypertensive patients of the European Lacidipine Study on Atherosclerosis (ELSA), office and ABP were measured before treatment and at 6-month (office BP) or 12-month (ABP) intervals during the 4-year administration of calcium channel blocker-based or ?-blocker-based treatment. The two groups were pooled and data were analyzed separately in patients with both office and ABP elevation (n=1670; sustained hypertension) or WCH (n=251; office BP elevation only). In sustained hypertension, office and 24-hour mean systolic BP were both markedly reduced through the treatment period, the mean change being -20.0±12.5 and -10.1±11.0 mm Hg, respectively (P<0.0001 for both). In striking contrast, in WCH the office BP reduction was almost as marked as in sustained hypertension (-19.1±11.2 mm Hg; P<0.0001), whereas 24-hour systolic BP values showed no fall or a slight progressive significant increase, its mean change during treatment being 1.6±8.6 mm Hg (P=0.007). Lowering of office BP occurred at a lower treatment intensity in WCH than in sustained hypertension. Similar findings were obtained for diastolic BP. In WCH, antihypertensive treatment should not be expected to have a lowering effect on ABP, even when office BP undergoes a concomitant marked and persistent reduction. The consequence of this contrasting effect on the incidence of hypertension-related outcomes remains to be established.
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Correlation between trans and intra-thoracic impedance and conductance in patients with chronic heart failure.
J Cardiovasc Med (Hagerstown)
PUBLISHED: 09-17-2014
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In chronic heart failure, changes of intra-thoracic impedance (Z0IT) may suggest impending pulmonary congestion; a similar result has been found by measuring trans-thoracic conductance (TFCTT?=?1/Z0?=?1/k?). We assumed that a relationship could exist between Z0IT and TFCTT.
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Gender and Acetazolamide Effects on Chemoreflex and Periodic Breathing During Sleep at Altitude.
Chest
PUBLISHED: 09-04-2014
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Background.Nocturnal periodic breathing occurs more frequently in males than in females in various clinical and pathophysiological conditions. The mechanisms accounting for this gender-related difference are not completely understood. Acetazolamide effectively counteracts nocturnal periodic breathing, but it has been investigated almost exclusively in males.Our aim was to explore possible determinants of nocturnal periodic breathing in a high-altitude setting. We hypothesized that: increased hypoxic chemosensitivity in males could be associated with development of nocturnal periodic breathing at altitude more frequently than in females; and that acetazolamide, by left-shifting the CO2 ventilatory response, could improve nocturnal periodic breathing at altitude in a gender-independent manner. Methods.44 healthy lowlanders (21 females), randomized to acetazolamide or placebo, underwent cardiorespiratory sleep studies at sea-level off treatment and under treatment on the first night after arrival at 4559m altitude. Hypoxic and hypercapnic chemosensitivities were assessed at sea-level. Results.Males exhibited increased hypoxic chemosensitivity, and displayed nocturnal periodic breathing at altitude more frequently than females. Acetazolamide leftward-shifted the CO2 set-point and, at altitude, improved oxygenation and reduced periodic breathing in both genders, but to a larger extent in males. Hypoxic chemosensitivity directly correlated with the number of apneas/hypopneas at altitude in the placebo group, but not in acetazolamide group. Conclusions.The greater severity of periodic breathing during sleep displayed by males at altitude could be attributed to their increased hypoxic chemosensitivity. Acetazolamide counteracted the occurrence of periodic breathing at altitude in both genders, modifying the apneic threshold and improving oxygenation. Clinical Trial Registration.EudraCT code-number 2010-019986-27.
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Changes in 24 h ambulatory blood pressure and effects of angiotensin II receptor blockade during acute and prolonged high-altitude exposure: a randomized clinical trial.
Eur. Heart J.
PUBLISHED: 08-26-2014
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Many hypertensive subjects travel to high altitudes, but little is known on ambulatory blood pressure (ABP) changes and antihypertensive drugs' efficacy under acute and prolonged exposure to hypobaric hypoxia. In particular, the efficacy of angiotensin receptor blockers in this condition is unknown. This may be clinically relevant considering that renin-angiotensin system activity changes at altitude. The HIGHCARE-HIMALAYA study assessed changes in 24 h ABP under acute and prolonged exposure to increasing altitude and blood pressure-lowering efficacy and safety of an angiotensin receptor blockade in this setting.
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Nocturnal intermittent hypoxia predicts prevalent hypertension in the European Sleep Apnoea Database cohort study.
Eur. Respir. J.
PUBLISHED: 08-07-2014
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Systemic hypertension is associated with obstructive sleep apnoea syndrome (OSAS) but the pathophysiological mechanisms are incompletely understood. A collaborative European network of 24 sleep centres established a European Sleep Apnoea Database to evaluate cardiovascular morbidity associated with OSAS. 11 911 adults referred with suspected OSAS between March 2007 and September 2013 underwent overnight sleep studies, either cardiorespiratory polygraphy or polysomnography. We compared the predictive value of the apnoea-hypopnoea index (AHI) and 4% oxygen desaturation index (ODI) for prevalent hypertension, adjusting for relevant covariates including age, smoking, obesity, dyslipidaemia and diabetes. Among patients (70% male, mean±sd age 52±12 years), 78% had AHI>5 events·h(-1) and 41% systemic hypertension. Both AHI and ODI independently related to prevalent hypertension after adjustment for relevant covariates (p<0.0001 for linear trend across quartiles (Q) of severity for both variables). However, in multiple regression analysis with both ODI and AHI in the model, ODI was, whereas AHI was not, independently associated with prevalent hypertension: odds ratios (95% CI) for Q4 versus Q1 regarding ODI were 2.01 (1.61-2.51) and regarding AHI were 0.92 (0.74-1.15) (p<0.0001 and p=0.3054, respectively). This cross sectional study suggests that chronic intermittent hypoxia plays an important role in OSAS-related hypertension.
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Management of heart failure in the new era: the role of scores.
J Cardiovasc Med (Hagerstown)
PUBLISHED: 08-02-2014
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Heart failure is a widespread syndrome involving several organs, still characterized by high mortality and morbidity, and whose clinical course is heterogeneous and hardly predictable.In this scenario, the assessment of heart failure prognosis represents a fundamental step in clinical practice. A single parameter is always unable to provide a very precise prognosis. Therefore, risk scores based on multiple parameters have been introduced, but their clinical utility is still modest.
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Blood pressure and LDL-cholesterol targets for prevention of recurrent strokes and cognitive decline in the hypertensive patient: design of the European Society of Hypertension-Chinese Hypertension League Stroke in Hypertension Optimal Treatment randomized trial.
J. Hypertens.
PUBLISHED: 07-01-2014
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The SBP values to be achieved by antihypertensive therapy in order to maximize reduction of cardiovascular outcomes are unknown; neither is it clear whether in patients with a previous cardiovascular event, the optimal values are lower than in the low-to-moderate risk hypertensive patients, or a more cautious blood pressure (BP) reduction should be obtained. Because of the uncertainty whether 'the lower the better' or the 'J-curve' hypothesis is correct, the European Society of Hypertension and the Chinese Hypertension League have promoted a randomized trial comparing antihypertensive treatment strategies aiming at three different SBP targets in hypertensive patients with a recent stroke or transient ischaemic attack. As the optimal level of low-density lipoprotein cholesterol (LDL-C) level is also unknown in these patients, LDL-C-lowering has been included in the design.
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Blood pressure and low-density lipoprotein-cholesterol lowering for prevention of strokes and cognitive decline: a review of available trial evidence.
J. Hypertens.
PUBLISHED: 07-01-2014
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It is well established by a large number of randomized controlled trials that lowering blood pressure (BP) and low-density lipoprotein cholesterol (LDL-C) by drugs are powerful means to reduce stroke incidence, but the optimal BP and LDL-C levels to be achieved are largely uncertain. Concerning BP targets, two hypotheses are being confronted: first, the lower the BP, the better the treatment outcome, and second, the hypothesis that too low BP values are accompanied by a lower benefit and even higher risk. It is also unknown whether BP lowering and LDL-C lowering have additive beneficial effects for the primary and secondary prevention of stroke, and whether these treatments can prevent cognitive decline after stroke.
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Circulating factors are involved in hypoxia-induced hepcidin suppression.
Blood Cells Mol. Dis.
PUBLISHED: 06-25-2014
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Hepcidin transcription is strongly down-regulated under hypoxic conditions, however whether hypoxia inhibits hepcidin directly or indirectly is still unknown. We investigated the time course of hypoxia-mediated hepcidin down-regulation in vivo in healthy volunteers exposed to hypobaric hypoxia at high altitude and, based on the hypothesis that circulating factors are implicated in hepcidin inhibition, we analyzed the effect of sera of these volunteers exposed to normoxia and hypoxia on hepcidin expression in Huh-7 cell lines. Hypoxia led to a significant hepcidin down-regulation in vivo that was almost complete within 72h of exposure and followed erythropoietin induction. This delay in hepcidin down-regulation suggests the existence of soluble factor/s regulating hepcidin production. We then stimulated HuH-7 cells with normoxic and hypoxic sera to analyze the effects of sera on hepcidin regulation. Hypoxic sera had a significant inhibitory effect on hepcidin promoter activity assessed by a luciferase assay, although the amount of such decrease was not as relevant as that observed in vivo. Cellular mRNA analysis showed that a number of volunteers' sera inhibited hepcidin expression, concurrently with ID1 inhibition, suggesting that inhibitory factor(s) may act through the SMAD-pathway.
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Efficacy of olmesartan/amlodipine combination therapy in reducing ambulatory blood pressure in moderate-to-severe hypertensive patients not controlled by amlodipine alone.
Hypertens. Res.
PUBLISHED: 06-19-2014
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This previously unpublished, preplanned analysis investigated the efficacy of the olmesartan/amlodipine combination at different doses on 24-h blood pressure (BP) control, as well as assessed trough estimation of trough-to-peak ratio (TPR) and smoothness index (SI). Ambulatory BP monitoring was performed in patients with moderate-to-severe hypertension whose BP was inadequately controlled after 8 weeks' treatment with amlodipine 5?mg. Patients were randomized to continue with amlodipine 5?mg or to receive olmesartan/amlodipine 10/5, 20/5 or 40/5?mg for 8 weeks (Period II). Patients not achieving BP control were uptitrated to a more powerful regimen for another 8 weeks (Period III). During Period II, each olmesartan/amlodipine combination reduced 24-h systolic and diastolic BP (SBP/DBP), as well as morning and early morning SBP/DBP, significantly more than amlodipine 5?mg (P<0.001 for all). TPRs were higher in each olmesartan/amlodipine group than with amlodipine 5?mg, and SI values showed dose-related increases; olmesartan/amlodipine 40/5?mg produced a significantly higher SI for SBP and DBP (1.55 and 1.33, respectively) than amlodipine 5?mg (0.96 and 0.77, respectively, P<0.0001 for each). During Period III, uptitrated patients showed further BP reductions, which were largest in those on olmesartan/amlodipine 40/10?mg. SI values increased in uptitrated patients and were highest with olmesartan/amlodipine 40/10?mg (SBP 1.62/DBP 1.41). The olmesartan/amlodipine combination effectively reduces BP over 24?h, including the morning hours, in a dose-related manner. Compared with amlodipine alone, the olmesartan/amlodipine combination has a better 24-h coverage (TPR) and a dose-related improvement in BP lowering homogeneity (SI).
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European Society of Hypertension practice guidelines for ambulatory blood pressure monitoring.
J. Hypertens.
PUBLISHED: 06-03-2014
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Given the increasing use of ambulatory blood pressure monitoring (ABPM) in both clinical practice and hypertension research, a group of scientists, participating in the European Society of Hypertension Working Group on blood pressure monitoring and cardiovascular variability, in year 2013 published a comprehensive position paper dealing with all aspects of the technique, based on the available scientific evidence for ABPM. The present work represents an updated schematic summary of the most important aspects related to the use of ABPM in daily practice, and is aimed at providing recommendations for proper use of this technique in a clinical setting by both specialists and practicing physicians. The present article details the requirements and the methodological issues to be addressed for using ABPM in clinical practice, The clinical indications for ABPM suggested by the available studies, among which white-coat phenomena, masked hypertension, and nocturnal hypertension, are outlined in detail, and the place of home measurement of blood pressure in relation to ABPM is discussed. The role of ABPM in pharmacological, epidemiological, and clinical research is also briefly mentioned. Finally, the implementation of ABPM in practice is considered in relation to the situation of different countries with regard to the reimbursement and the availability of ABPM in primary care practices, hospital clinics, and pharmacies.
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Impact of antihypertensive combination and monotreatments on blood pressure variability: assessment by old and new indices. Data from a large ambulatory blood pressure monitoring database.
J. Hypertens.
PUBLISHED: 04-25-2014
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High 24-h ambulatory blood pressure (ABP) variability is associated with poor cardiovascular outcomes. We analysed a large ABP monitoring database containing data from hypertensive patients treated with telmisartan/amlodipine combination or various monotherapies with the aim of quantifying the 24-h distribution of blood pressure (BP) reduction by treatment through the smoothness index and of developing and testing a new treatment-on-variability index (TOVI) to quantify the effects of treatment on both mean BP and BP variability.
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Prognostic value of noninvasive hemodynamic evaluation of the acute effect of levosimendan in advanced heart failure.
J Cardiovasc Med (Hagerstown)
PUBLISHED: 04-05-2014
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Optimization of inotropic treatment in worsening heart failure sometimes requires invasive hemodynamic assessment in selected patients. Impedance cardiography (ICG) may be useful for a noninvasive hemodynamic evaluation.
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Antihypertensive drug classes have different effects on short-term blood pressure variability in essential hypertension.
Hypertens. Res.
PUBLISHED: 03-27-2014
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Increased blood pressure variability (BPV) contributes to end-organ damage, cardiovascular events and mortality associated with hypertension. In a cohort of 2780 hypertensive patients treated by either calcium channel blockers (CCBs), diuretics, angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs) or ?-blockers alone or in combination, we compared indices of short-term BPV according to the different treatments. Short-term BPV was calculated as the standard deviation (s.d.) of 24?h, daytime or nighttime systolic blood pressure and diastolic blood pressure (SBP and DBP). Short-term BPV was compared between patients treated with a given antihypertensive class of interest (alone or in combination) and those not treated with this class, after controlling for ambulatory average blood pressure, heart rate, age, gender, propensity scores and carotid-femoral pulse wave velocity. Patients treated with CCBs (n=1247) or diuretics (n=1486) alone, or in addition to other drugs had significant lower s.d. of 24-h SBP compared with those not treated with these classes (mean differences in s.d. -0.50±0.50?mm?Hg, P=0.001 and -0.17±0.15?mm?Hg, P=0.05, respectively). There was no significant difference regarding treatment with or without ARBs, ACEIs and ?-blockers. The combinations of CCBs with diuretics or ARBs on top of other treatments resulted in a lower 24-h SBP variability (mean differences in s.d. -0.43±0.17?mm?Hg, P=0.02 and -0.44±0.19?mm?Hg, P=0.005 vs. other combination uses, respectively). Antihypertensive drug classes have differential effects on short-term BPV with a greater reduction in patients treated with CCBs and diuretics. The combinations of CCBs with diuretics may be the most efficient treatments in lowering BPV.
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Cardiovascular risk assessment in low-resource settings: a consensus document of the European Society of Hypertension Working Group on Hypertension and Cardiovascular Risk in Low Resource Settings.
J. Hypertens.
PUBLISHED: 03-01-2014
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The Global Burden of Diseases, Injuries, and Risk Factors Study 2010 confirms ischemic heart disease and stroke as the leading cause of death and that hypertension is the main associated risk factor worldwide. How best to respond to the rising prevalence of hypertension in resource-deprived settings is a topic of ongoing public-health debate and discussion. In low-income and middle-income countries, socioeconomic inequality and cultural factors play a role both in the development of risk factors and in the access to care. In Europe, cultural barriers and poor communication between health systems and migrants may limit migrants from receiving appropriate prevention, diagnosis, and treatment. To use more efficiently resources available and to make treatment cost-effective at the patient level, cardiovascular risk approach is now recommended. In 2011, The European Society of Hypertension established a Working Group on 'Hypertension and Cardiovascular risk in low resource settings', which brought together cardiologists, diabetologists, nephrologists, clinical trialists, epidemiologists, economists, and other stakeholders to review current strategies for cardiovascular risk assessment in population studies in low-income and middle-income countries, their limitations, possible improvements, and future interests in screening programs. This report summarizes current evidence and presents highlights of unmet needs.
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Blood pressure variability assessed by home measurements: a systematic review.
Hypertens. Res.
PUBLISHED: 02-20-2014
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Accumulating evidence suggests that day-by-day blood pressure (BP) variability assessed using self-measurements by patients at home (HBPV) provides useful information beyond that of average home BP. This systematic review summarizes the current evidence on day-by-day HBPV. A systematic literature search (PubMed) revealed 22 eligible articles. Independent prognostic value of day-by-day HBPV for cardiovascular events and total mortality was demonstrated in two outcome studies, whereas novel indices of variability had minimal or no independent prognostic ability. Although findings are not consistent among the studies, the evidence suggests that HBPV has an independent role in the progression of preclinical cardiac, arterial and renal damage and is affected by age, gender, average BP and heart rate level, antihypertensive treatment, antihypertensive drug class and other factors. However, there is large diversity among the available studies in the home BP monitoring protocols, the indices used to quantify HBPV and the end points selected for evaluation. Overall, these preliminary data largely based on heterogeneous studies indicate an important and independent role of day-by-day HBPV in the pathogenesis of hypertension-induced cardiovascular damage. Yet, fundamental questions remain unanswered, including the optimal variability index, the optimal home monitoring schedule required, the threshold that defines increased HBPV and the impact of treatment-induced variability change on organ damage and cardiovascular events. Until these questions are adequately addressed in future studies, HBPV should largely remain a research issue with limited practical value for individual patients.
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Obstructive sleep apnea syndrome as a cause of resistant hypertension.
Hypertens. Res.
PUBLISHED: 01-06-2014
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Evidence has consistently supported the association of obstructive sleep apnea syndrome (OSAS) with an increased prevalence of hypertension. It has also been shown that the severity of OSAS is directly correlated with the degree of blood pressure (BP) elevation and that hypertension occurring in subjects with OSAS is more likely to be severe, resistant to antihypertensive treatment and associated with alterations in day-to-night BP changes. Proposed mechanisms for the pathogenesis of OSAS-related hypertension include the activation of the sympathetic nervous system, alterations in autonomic cardiovascular (CV) modulation, the activation of the renin-angiotensin-aldosterone system, endothelial dysfunction, systemic and vascular inflammation, oxidative stress, metabolic abnormalities, arterial stiffness and alterations in cardiac function and structure. Given the adverse prognostic implications of OSAS-related hypertension for CV morbidity and mortality, the confirmation of resistant hypertension by using ambulatory BP monitoring (ABPM) and the identification of alterations in day-to-night BP changes is of the utmost importance to implement more aggressive strategies for achieving BP control. In turn, the proper identification and implementation of specific treatment strategies for OSAS (that is, continuous positive airway pressure) in subjects with resistant hypertension may promote BP control and optimize CV protection. The present paper will review the evidence supporting the association of OSAS with resistant hypertension and the proposed mechanisms for this association. It will also address the role of ABPM in the confirmation of resistant hypertension in subjects with OSAS and whether the proper identification and management of OSAS in subjects with resistant hypertension will improve BP control.
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Assessment of arterial stiffness for clinical and epidemiological studies: methodological considerations for validation and entry into the European Renal and Cardiovascular Medicine registry.
Nephrol. Dial. Transplant.
PUBLISHED: 09-30-2013
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Epidemiological studies have highlighted the role of arterial stiffness as a risk factor for development of cardiovascular (CV) diseases. Moreover, aortic stiffness has been shown to be a significant predictive factor of all-cause and CV mortality in different populations including patients with end-stage renal disease. Pulse-wave velocity (PWV) is the most widely used technique to assess arterial stiffness. Although PWV can be measured on any artery or between any arterial sites, only carotid-to-femoral PWV, representing stiffness of the aorta and iliofemoral axes, has been shown to have predictive value for morbidity and mortality. The several available commercial devices differ according to the type of signal (pressure, distension, flow) or by recording both sites simultaneously or using ECG synchronization. It is also possible to directly measure arterial diameter changes during the cardiac cycle and link them to local pulse-pressure changes, which provides the pressure-diameter relationship and stress-strain relationship if arterial wall thickness is also measured. These techniques are based on high-precision vascular echo tracking or magnetic resonance imaging and applanation tonometry. This paper summarizes the basic principles of arterial haemodynamics and various methodologies to assess stiffness and the latest consensus recommendations for clinical applications.
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Left ventricular ejection time, not heart rate, is an independent correlate of aortic pulse wave velocity.
J. Appl. Physiol.
PUBLISHED: 09-19-2013
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Several studies showed a positive association between heart rate and pulse wave velocity, a sensitive marker of arterial stiffness. However, no study involving a large population has specifically addressed the dependence of pulse wave velocity on different components of the cardiac cycle. The aim of this study was to explore in subjects of different age the link between pulse wave velocity with heart period (the reciprocal of heart rate) and the temporal components of the cardiac cycle such as left ventricular ejection time and diastolic time. Carotid-femoral pulse wave velocity was assessed in 3,020 untreated subjects (1,107 men). Heart period, left ventricular ejection time, diastolic time, and early-systolic dP/dt were determined by carotid pulse wave analysis with high-fidelity applanation tonometry. An inverse association was found between pulse wave velocity and left ventricular ejection time at all ages (<25 years, r(2) = 0.043; 25-44 years, r(2) = 0.103; 45-64 years, r(2) = 0.079; 65-84 years, r(2) = 0.044; ?85 years, r(2) = 0.022; P < 0.0001 for all). A significant (P < 0.0001) negative but always weaker correlation between pulse wave velocity and heart period was also found, with the exception of the youngest subjects (P = 0.20). A significant positive correlation was also found between pulse wave velocity and dP/dt (P < 0.0001). With multiple stepwise regression analysis, left ventricular ejection time and dP/dt remained the only determinant of pulse wave velocity at all ages, whereas the contribution of heart period no longer became significant. Our data demonstrate that pulse wave velocity is more closely related to left ventricular systolic function than to heart period. This may have methodological and pathophysiological implications.
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European society of hypertension position paper on ambulatory blood pressure monitoring.
J. Hypertens.
PUBLISHED: 09-14-2013
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Ambulatory blood pressure monitoring (ABPM) is being used increasingly in both clinical practice and hypertension research. Although there are many guidelines that emphasize the indications for ABPM, there is no comprehensive guideline dealing with all aspects of the technique. It was agreed at a consensus meeting on ABPM in Milan in 2011 that the 34 attendees should prepare a comprehensive position paper on the scientific evidence for ABPM.This position paper considers the historical background, the advantages and limitations of ABPM, the threshold levels for practice, and the cost-effectiveness of the technique. It examines the need for selecting an appropriate device, the accuracy of devices, the additional information and indices that ABPM devices may provide, and the software requirements.At a practical level, the paper details the requirements for using ABPM in clinical practice, editing considerations, the number of measurements required, and the circumstances, such as obesity and arrhythmias, when particular care needs to be taken when using ABPM.The clinical indications for ABPM, among which white-coat phenomena, masked hypertension, and nocturnal hypertension appear to be prominent, are outlined in detail along with special considerations that apply in certain clinical circumstances, such as childhood, the elderly and pregnancy, and in cardiovascular illness, examples being stroke and chronic renal disease, and the place of home measurement of blood pressure in relation to ABPM is appraised.The role of ABPM in research circumstances, such as pharmacological trials and in the prediction of outcome in epidemiological studies is examined and finally the implementation of ABPM in practice is considered in relation to the issue of reimbursement in different countries, the provision of the technique by primary care practices, hospital clinics and pharmacies, and the growing role of registries of ABPM in many countries.
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Sleep apnoea and the heart.
Eur Respir Rev
PUBLISHED: 09-03-2013
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Sleep apnoea is associated with significant daytime functioning impairment and marked cardiovascular morbidities, leading to a significant increase in mortality. Sympathetic activation, oxidative stress and systemic inflammation have been shown to be the main intermediary mechanisms associated with sleep apnoea and intermittent hypoxia. There are now convincing data regarding the association between hypertension, arrhythmias, coronary heart disease, heart failure, increased cardiovascular mortality and sleep apnoea. This has been evidenced in sleep apnoea patients and is supported by experimental data obtained in intermittent hypoxia. Whether treating sleep apnoea enables chronic cardiovascular consequences to be reversed is not fully established as regard coronary heart disease, arrhythmias and heart failure. In this late condition, complex bidirectional relationships occur, with obstructive sleep apnoea being a risk factor for heart failure whilst central sleep apnoea mainly appears as a consequence of heart failure. It remains to be established in adequately designed studies, i.e. large randomised controlled trials, whether treating sleep apnoea can improve heart failure morbidity and mortality.
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The effects of telmisartan alone or in combination with hydrochlorothiazide on morning home blood pressure control: the SURGE 2 practice-based study.
Blood Press.
PUBLISHED: 08-20-2013
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SURGE 2, a large-scale, practice-based study in 10 countries, evaluated the effects of telmisartan alone or with hydrochlorothiazide (HCTZ) on morning (06:00-11:59) home blood pressure (HBP) control. Hypertensive patients (clinic blood pressure [BP] ? 140/90 mmHg) received telmisartan 40 or 80 mg either alone or in combination with HCTZ 12.5 mg for 8 weeks. Treatment could be adjusted if clinic BP remained ? 140/90 mmHg. Clinic BP was measured in the morning prior to medication, and seated HBP monitoring was performed, three times per day, 2 days per week. A total of 25,882 patients were included (71% were previously using antihypertensives). There was a statistically significant (all p < 0.001) reduction in mean morning, lunchtime and evening HBP following treatment with telmisartan/telmisartan plus HCTZ, and morning HBP control increased from 10.6-19.8% to 51.1-64.6%. Similar improvements were observed for lunchtime (from 20.6-26.0% to 57.7-70.5%) and evening (from 21.3-31.4% to 59.0-68.8%). The morning HBP response ranged from 62.6-67.5% (systolic BP) and from 81.4-87.0% (diastolic BP). Adverse events were reported by 1.2% of patients. Telmisartan alone or with HCTZ improved morning HBP control and maintained a smooth HBP profile throughout the day in a real-life setting.
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Cardiac index assessment: Validation of a new non-invasive very low current thoracic bioimpedance device by thermodilution.
Blood Press.
PUBLISHED: 08-09-2013
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Introduction. The accuracy of impedance cardiography for cardiac index assessment is matter of debate, with available studies reporting inconsistent results. Our study aimed at evaluating the agreement between measurements of cardiac index provided by a new-generation thoracic electrical bioimpedance device (Hotman System) and an invasive approach based on thermodilution in humans. Methods. Cardiac index was assessed simultaneously with thoracic electrical bioimpedance and conventional thermodilution through comparison of five consecutive measurements in 51 cardiac patients, hospitalized in an intensive care unit (mean± SD age: 60 ± 11 years; 68% males). The agreement between cardiac index values measured by both methods was assessed by the Bland-Altman approach, adjusted for repeated measures. The repeatability coefficient and the intraclass correlation coefficient were used to assess reproducibility of replicates. Results. Average (± SD) cardiac index was 3.05 ± 0.91 l/min/m(2) with Hotman System and 3.14 ± 1.12 l/min/m(2) with thermodilution. The bias of precision was -0.09 ± 0.41. The coefficients of repeatability and intraclass correlation coefficients were high and similar for the two techniques (0.95 l/min/m(2) and 0.91 for Hotman System vs 0.78 l/min/m(2) and 0.90 for thermodilution). Conclusions. Cardiac index values yielded by Hotman system compares favorably with that obtained with thermodilution in cardiac patients.
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Carotid artery stenting in patients with acute coronary syndrome: a possible primary therapy for symptomatic carotid stenosis.
J. Endovasc. Ther.
PUBLISHED: 08-07-2013
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To report the results of carotid artery stenting (CAS) in symptomatic patients (stroke/transient ischemic attack) after recent percutaneous transluminal coronary angioplasty (PTCA) for acute coronary syndrome (ACS).
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Increased short-term blood pressure variability is associated with early left ventricular systolic dysfunction in newly diagnosed untreated hypertensive patients.
J. Hypertens.
PUBLISHED: 07-02-2013
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Twenty-four-hour blood pressure (BP) variability, by ambulatory BP monitoring (ABPM), has been related to left ventricular hypertrophy, independent of mean BP values. We tested the hypothesis that short-term BP variability (BPV) is also related to subclinical left ventricular systolic dysfunction.
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Left atrial enlargement and right ventricular hypertrophy in essential hypertension.
Blood Press.
PUBLISHED: 06-13-2013
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Aim. Diastolic dysfunction related to hypertensive left ventricular hypertrophy (LVH) has been shown to affect right-sided cardiac morphology and haemodynamics. As left atrial enlargement (LAE) is a marker of chronically elevated left ventricular (LV) filling pressure and diastolic dysfunction, we investigated the relationship between LAE and right ventricular hypertrophy (RVH) in systemic hypertension. Methods. A total of 330 essential hypertensives, categorized according to tertiles of left atrial (LA) diameter indexed to body surface area were considered for the analysis. All subjects underwent a quantitative echocardiographic examination as well as extensive clinical and laboratory investigations. RVH was defined as anterior right ventricular (RV) wall thickness ? 6.0/5.5 mm in men and women, respectively, and LVH as LV mass index ? 51/47 g/m(2.7) in men and women, respectively. Results. The prevalence of LVH increased across LA diameter tertiles from 21.0% to 50% and that of RVH from 26.3% to 41.8% (p < 0.01for both). This was also the case for biventricular hypertrophy (from 10.0% to 26.0%, p < 0.01). Differences in both LV and RV structure across LA diameter tertiles remained significant after adjusting for age, office systolic/diastolic blood pressure and duration of hypertension. Similar results were obtained when study population was divided according to absolute LA diameter tertiles. Conclusions. Our findings provide further evidence of an interaction between left and right chambers in systemic hypertension by showing that LAE is associated with RVH. The clinical and prognostic implications of such observation remain be evaluated in future prospective studies.
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Early vascular ageing in translation: from laboratory investigations to clinical applications in cardiovascular prevention.
J. Hypertens.
PUBLISHED: 06-08-2013
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The ageing of the vascular tree is a fundamental reflection of biological ageing in general and a determinant of organ function. In the arterial wall this is characterized by a reduction in the elastin content, as well as by an increased content of collagen and its cross-linkages, leading to increased arterial stiffness and elevated central as well as brachial blood pressure, accompanied by increased SBP variability. In recent years a better understanding of these processes have led to the proposal of a condition named early vascular ageing (EVA) in patients with increased arterial stiffness for their age and sex. This is a condition that could increase cardiovascular risk and is associated with various degrees of cognitive dysfunction, as well as other features of biological ageing. This brief review aims to give an update on EVA and how the concept can be used in clinical practice.
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Updated ESH position paper on interventional therapy of resistant hypertension.
EuroIntervention
PUBLISHED: 06-05-2013
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Out of the overall hypertensive population it is estimated that approximately 10% have treatment resistant hypertension (TRH). Percutaneous catheter-based transluminal renal ablation (renal denervation [RDN] by delivery of radiofrequency energy) has emerged as a new approach to achieve sustained blood pressure reduction in patients with TRH. This innovative interventional technique is now available across Europe for severe TRH for those patients in whom pharmacologic strategies and lifestyle changes have failed to control blood pressure below target (usually <140/90 mmHg). In 2012, the "ESH position paper: renal denervation - an interventional therapy of resistant hypertension" was published to facilitate a better understanding of the effectiveness, safety, limitation and unresolved issues. We have now updated this position paper since numerous studies have been published over the last year providing more data about the rationale, therapeutic efficacy and safety of RDN. In the upcoming ESH/ESC guidelines for the management of arterial hypertension, therapeutic options of treatment resistant hypertension will be addressed, but only briefly, and thus it is the focus of this paper to provide detailed and updated information on this innovative interventional technique.
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International expert consensus statement: percutaneous transluminal renal denervation for the treatment of resistant hypertension.
J. Am. Coll. Cardiol.
PUBLISHED: 06-02-2013
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Catheter-based radiofrequency ablation technology to disrupt both efferent and afferent renal nerves has recently been introduced to clinical medicine after the demonstration of significant systolic and diastolic blood pressure reductions. Clinical trial data available thus far have been obtained primarily in patients with resistant hypertension, defined as standardized systolic clinic blood pressure ?160 mm Hg (or ?150 mm Hg in patients with type 2 diabetes) despite appropriate pharmacologic treatment with at least 3 antihypertensive drugs, including a diuretic agent. Accordingly, these criteria and blood pressure thresholds should be borne in mind when selecting patients for renal nerve ablation. Secondary forms of hypertension and pseudoresistance, such as nonadherence to medication, intolerance of medication, and white coat hypertension, should have been ruled out, and 24-h ambulatory blood pressure monitoring is mandatory in this context. Because there are theoretical concerns with regard to renal safety, selected patients should have preserved renal function, with an estimated glomerular filtration rate ?45 ml/min/1.73 m(2). Optimal periprocedural management of volume status and medication regimens at specialized and experienced centers equipped with adequate infrastructure to cope with potential procedural complications will minimize potential patient risks. Long-term safety and efficacy data are limited to 3 years of follow-up in small patient cohorts, so efforts to monitor treated patients are crucial to define the long-term performance of the procedure. Although renal nerve ablation could have beneficial effects in other conditions characterized by elevated renal sympathetic nerve activity, its potential use for such indications should currently be limited to formal research studies of its safety and efficacy.
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Assessment and interpretation of blood pressure variability in a clinical setting.
Blood Press.
PUBLISHED: 04-29-2013
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Blood pressure (BP) is characterized by marked fluctuations occurring within the 24 h as a result of complex interactions between behavioral, environmental, humoral, and neural central or reflex influences. Significant BP variations also occur over more prolonged periods of time (i.e. between days, weeks, months, seasons and even years), not as a random phenomenon but as a result of several interacting factors yet not completely identified. Depending on the method and time interval considered for measurement, the clinical significance and prognostic implications of different types of BP variability (BPV) may substantially differ. Either in the short or in the long term, BPV has been associated with development, progression and severity of cardiac, vascular and renal organ damage and with an increased risk of cardiovascular events and mortality, independently adding to cardiovascular risk, over and above the contribution of elevated mean BP levels. The present paper provides a review on the main methods currently employed for assessment of BPV as well as on the mechanisms, clinical interpretation and prognostic significance of different types of BPV, addressing the question on whether BPV should be a target for antihypertensive treatment for the current prevention of cardiovascular disease.
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Morning and smooth 24-h ambulatory blood pressure control is not achieved in general practice: results from the SURGE observational study.
J. Hypertens.
PUBLISHED: 04-26-2013
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The aim of this large-scale, practice-based observational study [Survey with HBPM and ABPM Under Real clinical conditions in General practice to Evaluate BP control in the early morning (SURGE)] was to ascertain the degree of morning and 24-h ambulatory blood pressure (ABP) control in hypertensive patients.
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Acute high-altitude exposure reduces lung diffusion: data from the HIGHCARE Alps project.
Respir Physiol Neurobiol
PUBLISHED: 03-27-2013
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The causes and development of lung fluid, as well as the integrity of the alveolar-capillary membrane at high altitude, are undefined. This study was conceived to see whether fluid accumulates within the lung with acute high altitude exposure, and whether this is associated with alveolar capillary membrane damage. We studied lung carbon monoxide diffusion (DLCO), its components - membrane diffusion (DM) and capillary volume (VC) and alveolar volume (VA) measured in 43 healthy subjects in Milan (122 m) and after 1 and 3 days at Capanna Regina Margherita (4559 m). DLCO measurement was adjusted for hemoglobin and inspired oxygen. We also measured plasma surfactant derived protein B (SPB) and Receptor of Advanced Glycation End-products (RAGE) as markers of alveolar-capillary membrane damage, and ultrasound lung comets as a marker of extravascular lung water. 21 subjects received acetazolamide and 22 placebo. DLCO was lower at Capanna Regina Margherita (day 1: 24.3 ± 4.7 and day 3: 23.6 ± 5.4 mL/mmHg/min), than in Milan (25.8 ± 5.5; p<0.001 vs. day 1 and 3) due to DM reduction (Milan: 50.5 ± 14.6 mL/mmHg/min, Capanna Regina Margherita day 1: 45.1 ± 11.5 mL/mmHg/min, day 3: 43.2 ± 13.9 mL/mmHg/min; p<0.05 Milan vs. day 3) with a partially compensatory VC increase (Milan: 96 ± 37 mL, Capanna Regina Margherita day 1: 152 ± 66 mL, day 3: 153 ± 59 mL; p<0.001 Milan vs. day 1 and day 3). Acetazolamide did not prevent the fall in DLCO albeit, between day 1 and 3, such a trend was observed. Regardless of treatment lung comets increased from 0 to 7.2 ± 3.6 (p<0.0001). SPB and RAGE were unchanged. Lung fluid increased at high altitude without evidence from plasma measurements, supporting alveolar-capillary damage.
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Blood pressure variability over 24?h: prognostic implications and treatment perspectives. An assessment using the smoothness index with telmisartan-amlodipine monotherapy and combination.
Hypertens. Res.
PUBLISHED: 03-08-2013
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In-office blood pressure (BP) measurements have recognized limitations, including the inability to collect BP information over a long period of time, and during an individuals usual daily activities. Home or ambulatory BP monitoring (ABPM) may therefore be used to complement conventional office measurements, thereby improving prognostic value. Of particular relevance is the ability of 24?h ABPM to quantify the degree of BP variability over 24?h, which has been shown to be a significant and independent risk factor for cardiovascular (CV) morbidity and mortality. Twenty-four hour BP variability is indeed strongly associated with clinical outcomes, and the ability of ABPM to provide a quantification of BP throughout the 24-h period during an individuals normal daily routine is one of the reasons for its high prognostic value. The smoothness index (SI) provides a useful measure of antihypertensive treatment efficacy over the 24?h dosing period, its values being highest with antihypertensive agents that have large and consistent effects across 24?h. Telmisartan and amlodipine are long-acting antihypertensive drugs that, in combination, not only reduce 24?h mean BP more than the respective monotherapies but also provide a significantly greater SI. The provision of homogeneous 24?h BP control has important clinical implications. Maintaining smooth BP over the entire 24?h dosing period may contribute to the improvement of CV outcomes, and reductions in BP variability may decrease end organ damage, and reduce CV risk.Hypertension Research advance online publication, 5 December 2013; doi:10.1038/hr.2013.145.
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Changes in subendocardial viability ratio with acute high-altitude exposure and protective role of acetazolamide.
Hypertension
PUBLISHED: 02-25-2013
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High-altitude tourism is increasingly frequent, involving also subjects with manifest or subclinical coronary artery disease. Little is known, however, on the effects of altitude exposure on factors affecting coronary perfusion. The aim of our study was to assess myocardial oxygen supply/demand ratio in healthy subjects during acute exposure at high altitude and to evaluate the effect of acetazolamide on this parameter. Forty-four subjects (21 men, age range: 24-59 years) were randomized to double-blind acetazolamide 250 mg bid or placebo. Subendocardial viability ratio and oxygen supply/demand ratio were estimated on carotid artery by means of a validated PulsePen tonometer, at sea level, before and after treatment, and after acute and more prolonged exposure to high altitude (4559 m). On arrival at high altitude, subendocardial viability ratio was reduced in both placebo (from 1.63±0.15 to 1.18±0.17; P<0.001) and acetazolamide (from 1.68±0.25 to 1.35±0.18; P<0.001) groups. Subendocardial viability ratio returned to sea level values (1.65±0.24) after 3 days at high altitude under acetazolamide but remained lower than at sea level under placebo (1.42±0.22; P<0.005 versus baseline). At high altitude, oxygen supply/demand ratio fell both under placebo (from 29.6±4.0 to 17.3±3.0; P<0.001) and acetazolamide (from 32.1±7.0 to 22.3±4.6; P<0.001), its values remaining always higher (P<0.001) on acetazolamide. Administration of acetazolamide may, thus, antagonize the reduction in subendocardial oxygen supply triggered by exposure to hypobaric hypoxia. Further studies involving also subjects with known or subclinical coronary artery disease are needed to confirm a protective action of acetazolamide on myocardial viability under high-altitude exposure.
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Environmental and genetic contribution to hypertension prevalence: data from an epidemiological survey on Sardinian genetic isolates.
PLoS ONE
PUBLISHED: 02-15-2013
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Hypertension represents a major cause of cardiovascular morbidity and mortality worldwide but its prevalence has been shown to vary in different countries. The reasons for such differences are still matter of debate, the relative contributions given by environmental and genetic factors being still poorly defined. We estimated the current prevalence, distribution and determinants of hypertension in isolated Sardinian populations and also investigated the environmental and genetic contribution to hypertension prevalence taking advantage of the characteristics of such populations.
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Assessment and management of blood-pressure variability.
Nat Rev Cardiol
PUBLISHED: 02-12-2013
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Blood pressure (BP) is characterized by marked short-term fluctuations occurring within a 24 h period (beat-to-beat, minute-to-minute, hour-to-hour, and day-to-night changes) and also by long-term fluctuations occurring over more-prolonged periods of time (days, weeks, months, seasons, and even years). Rather than representing background noise or a randomly occurring phenomenon, these variations have been shown to be the result of complex interactions between extrinsic environmental and behavioural factors and intrinsic cardiovascular regulatory mechanisms. Although the adverse cardiovascular consequences of hypertension largely depend on absolute BP values, evidence from observational studies and post-hoc analyses of data from clinical trials have indicated that these outcomes might also depend on increased BP variability (BPV). Increased short-term and long-term BPV are associated with the development, progression, and severity of cardiac, vascular, and renal damage and with an increased risk of cardiovascular events and mortality. Of particular interest are the findings from post-hoc analyses of large intervention trials in hypertension, showing that within-patient visit-to-visit BPV is strongly prognostic for cardiovascular morbidity and mortality. This result has prompted discussion on whether antihypertensive treatment should be targeted not only towards reducing mean BP levels but also to stabilizing BPV with the aim of achieving consistent BP control over time, which might favour cardiovascular protection.
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Recommendations for the management of patients with obstructive sleep apnoea and hypertension.
Eur. Respir. J.
PUBLISHED: 02-08-2013
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This article is aimed at addressing the current state-of-the-art in epidemiology, pathophysiology, diagnostic procedures and treatment options for appropriate management of obstructive sleep apnoea (OSA) in cardiovascular (in particular hypertensive) patients, as well as for the management of cardiovascular diseases (in particular arterial hypertension) in OSA patients. The present document is the result of work performed by a panel of experts participating in the European Union COST (Cooperation in Scientific and Technological research) Action B26 on OSA, with the endorsement of the European Respiratory Society and the European Society of Hypertension. In particular, these recommendations are aimed at reminding cardiovascular experts to consider the occurrence of sleep-related breathing disorders in patients with high blood pressure. They are also aimed at reminding respiration experts to consider the occurrence of hypertension in patients with respiratory problems at night.
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Effects of acute and long-term slow breathing exercise on muscle sympathetic nerve activity in untreated male patients with hypertension.
J. Hypertens.
PUBLISHED: 02-07-2013
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Acute slow breathing (SLOWB) affects sympathetic cardiovascular regulation, but its long-term effects are unknown. Using device-guided breathing we explored short-term and long-term SLOWB effects on blood pressure (BP), heart rate (HR) and muscle sympathetic nerve activity (MSNA) in essential hypertension.
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Seasonal blood pressure changes: an independent relationship with temperature and daylight hours.
Hypertension
PUBLISHED: 02-04-2013
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Seasonal blood pressure (BP) changes have been found to be related to either outdoor or indoor temperature. No information regarding the independent effects of temperature measured proximally to the patient, the personal-level environmental temperature (PET), is available. Inclusion of daylight hours in multivariate analysis might allow exploring the independent interaction of BP with seasonality. To investigate whether ambulatory BP monitoring is affected by PET or by seasonality, 1897 patients referred to our hypertension units underwent ambulatory BP monitoring with a battery-powered temperature data logger fitted to the carrying pouch of the monitor. Predictors of 24-hour daytime and nighttime BP and of morning BP surge were investigated with a multivariate stepwise regression model, including age, sex, body mass index, antihypertensive treatment, office BP, ambulatory heart rate, PET, relative humidity, atmospheric pressure, and daylight hours as independent variables. At adjusted regression analysis, daytime systolic BP was negatively related to PET (-0.14; 95% confidence interval, -0.25 to -0.02); nighttime BP was positively related to daylight hours (0.63; 0.37-0.90); and morning BP surge was negatively related to daylight hours (-0.54; -0.87 to -0.21). These results provide new evidence that PET and seasonality (daylight hours) are 2 independent predictors of ambulatory BP monitoring.
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Transthoracic bioimpedance and brain natriuretic peptide assessment for prognostic stratification of outpatients with chronic systolic heart failure.
Clin Cardiol
PUBLISHED: 02-03-2013
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In patients with chronic heart failure, physical evaluation and clinical judgment may be inadequate for prognostic stratification.
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Blood pressure control and treatment adherence in hypertensive patients with metabolic syndrome: protocol of a randomized controlled study based on home blood pressure telemonitoring vs. conventional management and assessment of psychological determinants
Trials
PUBLISHED: 01-23-2013
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Inadequate blood pressure control and poor adherence to treatment remain among the major limitations in the management of hypertensive patients, particularly of those at high risk of cardiovascular events. Preliminary evidence suggests that home blood pressure telemonitoring (HBPT) might help increasing the chance of achieving blood pressure targets and improve patients therapeutic adherence. However, all these potential advantages of HBPT have not yet been fully investigated.
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Italian society of hypertension guidelines for conventional and automated blood pressure measurement in the office, at home and over 24 hours.
High Blood Press Cardiovasc Prev
PUBLISHED: 01-22-2013
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This article offers instructions and recommendations on how to perform blood pressure measurements in the doctors office, in the patients home and in ambulatory conditions over 24 hours. Great attention is paid to some of the general aspects of blood pressure measurement, including the accuracy of blood pressure measuring devices, the importance of a white-coat effect, and the need for patient education. This article also deals with a number of practical details, such as the importance of patients relaxation and position, arm position and support, arm selection and cuff selection and application. Recommendations are provided on the observers position and performance, and on the need to pay attention to specific factors affecting the blood pressure measurement in different patient populations, namely in children, elderly and obese people, pregnant women, patients with arrhythmias and patients on treatment. This article then separately focuses on the characteristics of auscultatory and automated measurements, the latter performed either in the office, at home or over 24 hours in ambulatory settings. Home blood pressure monitoring (HBPM) is becoming increasingly important in the diagnosis and management of arterial hypertension. The importance of HBPM in cardiovascular prevention, related to a deeper involvement of patients in their long-term management, and the wide diffusion of this approach in populations, is not always accompanied by adequate knowledge of how to make proper use of this technique, which emphasizes the need for more precise recommendations. This article summarizes the available evidence and provides recommendations on the use of home blood pressure monitoring in clinical practice and in research. It updates the previous recommendations on the same topic issued in 2000. The main topics addressed include the methodology of HBPM, focusing on measurement conditions and procedures, ranging from patient/subject position, to arm selection, arm position and support, cuff selection and application and data reporting, diagnostic and therapeutic thresholds, clinical applications in hypertension (with specific reference to special populations) and its applications in research. Special attention is given to device validation and selection as well as to patient education and to the need of HBPM to be guided by the physician in charge. The final section deals with the problems related to the implementation of these recommendations in clinical practice. Finally, the methodology and clinical impact of 24-hour ambulatory blood pressure monitoring are also addressed in detail, focusing on the parameters that can be derived from the analysis of 24-hour blood pressure recordings applied both to the diagnostic and prognostic evaluation of hypertensive patients and to the assessment of the effectiveness of antihypertensive treatment in controlling blood pressure through the day and night. Instructions to users on how to properly perform HBPM are provided as an appendix.
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Long-term blood pressure changes induced by the 2009 LAquila earthquake: assessment by 24 h ambulatory monitoring.
Hypertens. Res.
PUBLISHED: 01-21-2013
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An increased rate of cardiovascular and cerebrovascular events has been described during and immediately after earthquakes. In this regard, few data are available on long-term blood pressure control in hypertensive outpatients after an earthquake. We evaluated the long-term effects of the April 2009 LAquila earthquake on blood pressure levels, as detected by 24 h ambulatory blood pressure monitoring. Before/after (mean±s.d. 6.9±4.5/14.2±5.1 months, respectively) the earthquake, the available 24 h ambulatory blood pressure monitoring data for the same patients were extracted from our database. Quake-related daily life discomforts were evaluated through interviews. We enrolled 47 patients (25 female, age 52±14 years), divided into three groups according to antihypertensive therapy changes after versus before the earthquake: unchanged therapy (n=24), increased therapy (n=17) and reduced therapy (n=6). Compared with before the quake, in the unchanged therapy group marked increases in 24 h (P=0.004), daytime (P=0.01) and nighttime (P=0.02) systolic blood pressure were observed after the quake. Corresponding changes in 24 h (P=0.005), daytime (P=0.01) and nighttime (P=0.009) diastolic blood pressure were observed. Daily life discomforts were reported more frequently in the unchanged therapy and increased therapy groups than the reduced therapy group (P=0.025 and P=0.018, respectively). In conclusion, this study shows that patients with unchanged therapy display marked blood pressure increments up to more than 1 year after an earthquake, as well as long-term quake-related discomfort. Our data suggest that particular attention to blood pressure levels and adequate therapy modifications should be considered after an earthquake, not only early after the event but also months later.
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Clinical usefulness and cost effectiveness of home blood pressure telemonitoring: meta-analysis of randomized controlled studies.
J. Hypertens.
PUBLISHED: 01-10-2013
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To systematically review data from randomized controlled studies on the effectiveness of home blood pressure telemonitoring (HBPT) versus usual care with respect to improvement of BP control, healthcare resources utilization and costs, patients quality of life and adverse events.
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High-altitude hypoxia and periodic breathing during sleep: gender-related differences.
J Sleep Res
PUBLISHED: 01-07-2013
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High-altitude exposure is characterized by the appearance of periodic breathing during sleep. Only limited evidence is available, however, on the presence of gender-related differences in this breathing pattern. In 37 healthy subjects, 23 male and 14 female, we performed nocturnal cardio-respiratory monitoring in the following conditions: (1) sea level; (2) first/second night at an altitude of 3400 m; (3) first/second night at an altitude of 5400 m and after a 10 day sojourn at 5400 m. At sea level, a normal breathing pattern was observed in all subjects throughout the night. At 3400 m the apnea-hypopnea index was 40.3 ± 33.0 in males (central apneas 77.6%, central hypopneas 22.4%) and 2.4 ± 2.8 in females (central apneas 58.2%, central hypopneas 41.8%; P < 0.01). During the first recording at 5400 m, the apnea-hypopnea index was 87.5 ± 35.7 in males (central apneas 60.0%, central hypopneas 40.0%) and 41.1 ± 44.0 in females (central apneas 73.2%, central hypopneas 26.8%; P < 0.01), again with a higher frequency of central events in males as seen at lower altitude. Similar results were observed after 10 days. With increasing altitude, there was also a progressive reduction in respiratory cycle length during central apneas in males (26.9 ± 3.4 s at 3400 m and 22.6 ± 3.7 s at 5400 m). Females, who displayed a significant number of central apneas only at the highest reached altitude, were characterized by longer cycle length than males at similar altitude (30.1 ± 5.8 s at 5400 m). In conclusion, at high altitude, nocturnal periodic breathing affects males more than females. Females started to present a significant number of central sleep apneas only at the highest reached altitude. After 10 days at 5400 m gender differences in the apnea-hypopnea index similar to those observed after acute exposure were still observed, accompanied by differences in respiratory cycle length.
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Glucose tolerance and weight loss in obese women with obstructive sleep apnea.
PLoS ONE
PUBLISHED: 01-01-2013
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The association of obstructive sleep apnea (OSA) with glucose intolerance and the beneficial effect of lifestyle intervention have been poorly investigated in women particularly before menopausal status. The study explored 1) whether OSA is associated with impaired glucose homeostasis in obese non diabetic premenopausal and menopausal women and 2) the effects of a 3- month lifestyle intervention on glucose homeostasis in OSA women.
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Home blood pressure control is low during the critical morning hours in patients with hypertension: the SURGE observational study.
Fam Pract
PUBLISHED: 12-26-2011
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The morning blood pressure (BP) surge is associated with a peak increase in vascular events.
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Modulation of urinary peptidome in humans exposed to high altitude hypoxia.
Mol Biosyst
PUBLISHED: 12-07-2011
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The exposure of healthy subjects to high altitude represents a model to explore the pathophysiology of diseases related to tissue hypoxia and to evaluate pharmacological approaches potentially useful as a therapy for chronic diseases related to hypoxia. We explored the urinary peptidome to detect alterations induced by the exposure of subjects to different altitudes (sea level, high altitude = 3500 m, very high altitude = 5400 m) and to pharmacological treatment. Urine samples were collected from 47 subjects, randomly and blindly assigned to placebo (n = 24) or Telmisartan (n = 23). Samples were purified by the use of magnetic beads, then analysed by MALDI-TOF MS. Results showed that the urinary peptidome is not affected by the administration of Telmisartan, neither at the sea level nor at high and very high altitudes. In contrast, the urinary protein profiles are modified when subjects are exposed to high and very high altitudes, and we detected six peptides differentially expressed in hypobaric hypoxia at high or very high altitude compared to the sea level. Two of them were identified as fragments of the glycoprotein uromodulin and of the ?1-antitrypsin. This is the first proteomic study showing that hypobaric hypoxia conditions affect the urinary peptidome.
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Orthostatic hypertension: home blood pressure monitoring for detection and assessment of treatment with doxazosin.
Hypertens. Res.
PUBLISHED: 09-15-2011
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To determine the role of home blood pressure (BP) monitoring for a reproducible assessment of orthostatic hypertension (OHT) and the effectiveness of hypertension control by doxazosin. In this study, 605 medicated hypertensive outpatients were enrolled. Home BP in the sitting and standing positions was monitored in all patients in the morning and evening for 6 months. According to an open-label multicenter trial design, the patients were randomly allocated to either an intervention group that took doxazosin (1-4 mg) at bedtime or to a control group that did not receive any add-on medication. The patients were divided into deciles of orthostatic BP change as evaluated by home BP monitoring at baseline. Those in the top decile, in the lowest decile and in deciles two through eight were then assigned to the OHT group, the orthostatic hypotension group and the orthostatic normotension group, respectively.Orthostatic BP in the OHYPO group did not change, whereas that of the OHT group was markedly reduced by doxazosin (P<0.01). In the control group, classification into orthostatic BP categories using home BP monitoring was more reproducible (? coefficient: 0.42-0.50) than when using clinical BP (? coefficient: 0.13-0.24). In all groups, a reduction in the urinary albumin/creatinine ratio was significantly associated with a reduction in orthostatic BP doxazosin (P<0.001).The identification of OHT based on home BP monitoring was highly reproducible. The administration of doxazosin might control OHT and consequently prevent target organ damage.
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Transthoracic impedance accurately estimates pulmonary wedge pressure in patients with decompensated chronic heart failure.
Congest Heart Fail
PUBLISHED: 09-14-2011
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Routine cardiac catheterization to assess pulmonary capillary wedge pressure (PCWP) is not recommended in heart failure (HF), and various noninvasive tools have been proposed. The authors evaluated the reliability of echocardiography, brain natriuretic peptide (BNP), and thoracic electrical bioimpedance (TEB) in predicting PCWP in 29 patients (72±4?years, New York Heart Association class 3.5±0.9, ejection fraction 28%±6%) who underwent hemodynamic evaluation for worsening HF. Echocardiography was performed immediately before the hemodynamic study. During clinical stability, PCWP, plasma BNP, and TEB were simultaneously assessed. Among TEB variables, thoracic conductance (thoracic fluid content [TFC]=1/k?) was used. PCWP was related with E/E obtained with mitral Doppler and mitral annulus tissue Doppler imaging echocardiography (?R=0.55, P<.005), with BNP levels (R=0.43, P<.01) and TFC values (R=0.69, P<.001). For detection of PCWP ?15?mm?Hg, TFC ?35/k? had high specificity (97%) and sensitivity (86%) and negative (92%) and positive (97%) predictive value, while E/E and BNP levels had poorer specificity. After infusion of the inodilator levosimendan, changes in TFC and PCWP were of the same order of magnitude and mutually related. In worsening HF, TEB could help avoid right heart catheterization, since it may estimate PCWP better than BNP or echocardiography. Moreover, TFC could be used for noninvasive assessment of drugs effect.
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Cardiac sounds from a wearable device for sternal seismocardiography.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 08-29-2011
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Seismocardiography is the body-surface recording of vibrations produced by the beating heart. A high frequency (HF) accelerometric component of the seismocardiogram (SCG) is related to the heart sounds generated by the closure of atrio-ventricular and semilunar valves. This paper evaluates the feasibility of recording the SCG component associated to cardiac sounds by means of a wearable device originally designed for monitoring ECG, respiratory movements, body accelerations and posture in freely moving subjects. The method is based on the averaging of the HF component of the acceleration vector measured by the wearable system, and on the subsequent extraction of features from its envelope. The method is applied on data recorded in healthy volunteers in different postures and during sleep. Results indicate that it is possible to reliably identify the time of occurrence of the first and second heart sound within the cardiac cycle. They also show significant differences in the HF component of SCG between supine and standing postures. Analyzing the HF SCG in a volunteer sleeping at high altitude (4554 m asl) substantial differences were also found among three body positions (lying supine or on the left or right side). These differences are likely to reflect changes in cardiac mechanics induced by different postures of the body.
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A wearable system for the seismocardiogram assessment in daily life conditions.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 08-29-2011
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Seismocardiogram (SCG) is the recording of the minute body accelerations induced by the heart activity, and reflects mechanical aspects of heart contraction and blood ejection. So far, most of the available systems for the SCG assessment are designed to be used in a laboratory or in controlled behavioral and environmental conditions. In this paper we propose a modified version of a textile-based wearable device for the unobtrusive recording of ECG, respiration and accelerometric data (the MagIC system), to assess the 3d sternal SCG in daily life. SCG is characterized by an extremely low magnitude of the accelerations (in the order of g × 10(-3)), and is masked by major body accelerations induced by locomotion. Thus in daily life recordings, SCG can be measured whenever the subject is still. We observed that about 30 seconds of motionless behavior are sufficient for a stable estimate of the average SCG waveform, independently from the subjects posture. Since it is likely that during spontaneous behavior the subject may stay still for at least 30 seconds several times in a day, it is expected that the SCG could be repeatedly estimated and tracked over time through a prolonged data recording. These observations represent the first testing of the system in the assessment of SCG out of a laboratory environment, and open the possibility to perform SCG studies in a wide range of everyday conditions without interfering with the subjects activity tasks.
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Assessing the fractal structure of heart rate by the temporal spectrum of scale exponents: a new approach for detrended fluctuation analysis of heart rate variability.
Biomed Tech (Berl)
PUBLISHED: 05-16-2011
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Detrended fluctuation analysis (DFA) is the most popular method for assessing the fractal characteristics of heart rate (HR). Traditionally, short-term and long-term scale coefficients, ?(1) and ?(2), are calculated from DFA. We recently showed that the traditional approach oversimplifies a more complex phenomenon better represented by a continuous spectrum of scale coefficients. In this paper we present a DFA based method for describing the HR fractal dynamics with a temporal spectrum of scale exponents, ?(t), rather than by a model of lumped parameters, ?(1) and ?(2). Since ?(t) is a function of the temporal scale, its interpretation is facilitated when conditions with different mean HR are compared. In this work, we reanalyze HR data, collected by our group in previous studies, by applying the proposed ?(t) spectrum. We quantify the effects of gender, ageing, posture and activity level, and the alterations induced by exposure to high and very-high altitude hypoxia, on ?(t). Most of the results may be interpreted in terms of changes of cardiac autonomic regulation, and indicate clearly that the new proposed DFA spectrum provides a more faithful and interpretable description of the HR fractal dynamics than traditional ?(1) and ?(2) scale coefficients.
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Benefits of tight blood pressure control in diabetic patients with hypertension: importance of early and sustained implementation of effective treatment strategies.
Diabetes Care
PUBLISHED: 04-29-2011
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In 2008, when the UK Prospective Diabetes Study (UKPDS) group presented their 30-year findings concerning the possible sustained effects of improved glycemic control after 10 years of extended follow-up in type 2 diabetic patients, a so-called "legacy effect" was reported to address the long-term emergent and/or sustained benefits of early improved glycemic control. Opposite results were obtained by the Hypertension in Diabetes Study (HDS) carried out in the frame of UKPDS, with no evidence of any legacy effect on cardiovascular (CV) outcomes for an initial 4-year period of tight blood pressure (BP) control. Thus, it was concluded that BP control has to be continued over time, since, although it had a short time-to-effect relationship in preventing stroke, BP control was associated with a short persistence of its clinical benefits once the intervention was discontinued. These findings are unique because, whereas most interventional trials in hypertension that included diabetic patients have shown a reduction in CV outcomes shortly after starting treatment, only the UKPDS-HDS specifically explored the possible persistence of clinical benefits after discontinuing intensive BP-lowering intervention. This article aims to provide a critical interpretation of the UKPDS findings of lack of BP legacy, in the context of the currently available evidence on the benefits of antihypertensive treatment. The importance of effective BP control in type 2 diabetic patients to prevent CV outcomes and other diabetes-related complications is underlined, with emphasis on early, tight, and continuous BP control to optimize patients protection.
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Cardiovascular and noncardiovascular comorbidities in patients with chronic heart failure.
J Cardiovasc Med (Hagerstown)
PUBLISHED: 04-26-2011
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A broad spectrum of concomitant disorders may complicate heart failure adding further morbidity and mortality risk. Comorbidities may be subdivided into cardiovascular and noncardiovascular. The first group includes hypertension, coronary artery disease, peripheral artery disease, cerebrovascular disease, arrhythmias and valvular heart disease. Noncardiovascular comorbidities include respiratory, endocrine, metabolic, nutritional, renal, hematopoietic, neurological as well as musculoskeletal conditions. In recent years, advances in the treatment of heart failure have not been attended by important changes in management of its comorbidities. They now seem to be major causes of the poor prognosis of heart failure patients. In this review we provide an updated summary of the epidemiological, pathophysiological and clinical characteristics of comorbidities as well as their potential impact for heart failure treatment.
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Arterial stiffness and 24 h ambulatory blood pressure monitoring in young healthy volunteers: the early vascular ageing Aristotle University Thessaloniki Study (EVA-ARIS Study).
Atherosclerosis
PUBLISHED: 04-19-2011
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Differences in 24 h blood pressure (BP) monitoring parameters such as average 24 h BP, day to night BP ratio and BP variability could have an impact in arterial stiffness. The study hypothesis was that despite similar average BP values in ambulatory blood pressure monitoring subjects with increased 24 h BP variability may have increased arterial stiffness. The study population consisted of 115 consecutive young healthy volunteers. Carotid-femoral PWV was measured in all subjects. Clinic BP was measured and an appropriate cuff was fitted on the non-dominant arm of each subject for a 24 h ambulatory blood pressure monitoring session. Waist to hip ratio as well as BMI was measured. Family history and smoking habits were recorded. In univariate analysis, estimated carotid-femoral PWV showed a significant correlation with age, weight, waist circumference, height, clinic systolic and diastolic BP, 24-h systolic and diastolic BP, 24-h pulse pressure, 24-h systolic and diastolic BP variability, daytime systolic and diastolic BP, daytime pulse pressure, daytime systolic and diastolic BP variability, nighttime systolic BP, nighttime pulse pressure and nighttime systolic BP variability. In multivariate regression analysis, age (B=0.95, P<0.001) and 24 h systolic BP variability (B=0.28, P<0.001) were independent determinanats of arterial stiffness. In conclusions, increased 24 h systolic BP variability is associated with arterial stiffness in young healthy volunteers. Pulse wave velocity in a young healthy population is useful to identify determinants of premature arterial stiffness, thus further elucidating the aspects of early vascular ageing.
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Index measured at an intermediate altitude to predict impending acute mountain sickness.
Med Sci Sports Exerc
PUBLISHED: 03-31-2011
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Acute mountain sickness (AMS) is a neurological disorder that may be unpredictably experienced by subjects ascending at a high altitude. The aim of the present study was to develop a predictive index, measured at an intermediate altitude, to predict the onset of AMS at a higher altitude.
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High-altitude exposure of three weeks duration increases lung diffusing capacity in humans.
J. Appl. Physiol.
PUBLISHED: 03-24-2011
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high-altitude adaptation leads to progressive increase in arterial Pa(O2). In addition to increased ventilation, better arterial oxygenation may reflect improvements in lung gas exchange. Previous investigations reveal alterations at the alveolar-capillary barrier indicative of decreased resistance to gas exchange with prolonged hypoxia adaptation, but how quickly this occurs is unknown. Carbon monoxide lung diffusing capacity and its major determinants, hemoglobin, alveolar volume, pulmonary capillary blood volume, and alveolar-capillary membrane diffusion, have never been examined with early high-altitude adaptation.
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Effects of beta-blockade on exercise performance at high altitude: a randomized, placebo-controlled trial comparing the efficacy of nebivolol versus carvedilol in healthy subjects.
Cardiovasc Ther
PUBLISHED: 03-11-2011
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Exposure to high altitude (HA) hypoxia decreases exercise performance in healthy subjects. Although ?-blockers are known to affect exercise capacity in normoxia, no data are available comparing selective and nonselective ?-adrenergic blockade on exercise performance in healthy subjects acutely exposed to HA hypoxia. We compared the impact of nebivolol and carvedilol on exercise capacity in healthy subjects acutely exposed to HA hypobaric hypoxia.
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Diastolic dysfunction and abnormal exercise ventilation predict adverse outcome in elderly patients with chronic systolic heart failure.
Eur J Prev Cardiol
PUBLISHED: 03-10-2011
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Heart failure is increasing in the elderly and represents a socioeconomic burden requiring the correct management for which risk stratification is mandatory. Among younger patients, echocardiogram and cardiopulmonary exercise test are useful in prognostic stratification. Few studies have analyzed the utility of these tests in elderly patients.
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Cardiac oxygen supply is compromised during the night in hypertensive patients.
Med Biol Eng Comput
PUBLISHED: 02-28-2011
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The enhanced heart rate and blood pressure soon after awaking increases cardiac oxygen demand, and has been associated with the high incidence of acute myocardial infarction in the morning. The behavior of cardiac oxygen supply is unknown. We hypothesized that oxygen supply decreases in the morning and to that purpose investigated cardiac oxygen demand and oxygen supply at night and after awaking. We compared hypertensive to normotensive subjects and furthermore assessed whether pressures measured non-invasively and intra-arterially give similar results. Aortic pressure was reconstructed from 24-h intra-brachial and simultaneously obtained non-invasive finger pressure in 14 hypertensives and 8 normotensives. Supply was assessed by Diastolic Time Fraction (DTF, ratio of diastolic and heart period), demand by Rate-Pressure Product (RPP, systolic pressure times heart rate, HR) and supply/demand ratio by A(dia)/A(sys), with A(dia) and A(sys) diastolic and systolic areas under the aortic pressure curve. Hypertensives had lower supply by DTF and higher demand by RPP than normotensives during the night. DTF decreased and RPP increased in both groups after awaking. The DTF of hypertensives decreased less becoming similar to the DTF of normotensives in the morning; the RPP remained higher. A(dia)/A(sys) followed the pattern of DTF. Findings from invasively and non-invasively determined pressure were similar. The cardiac oxygen supply/demand ratio in hypertensive patients is lower than in normotensives at night. With a smaller night-day differences, the hypertensives risk for cardiovascular events may be more evenly spread over the 24 h. This information can be obtained noninvasively.
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Blood pressure control by the nifedipine GITS-telmisartan combination in patients at high cardiovascular risk: the TALENT study.
J. Hypertens.
PUBLISHED: 01-22-2011
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Guidelines on hypertension regard combinations between two antihypertensive drugs to be the most important treatment strategy. Because of the complementary mechanism of action and the evidence of cardiovascular protective effects they include the combination of a calcium antagonist and an angiotensin receptor antagonist among the priorital ones to employ.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.