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Objectives: Arterial hypertension is a common cause of cardiac organ damage, inducing morphological and functional modifications. Spontaneous baroreflex sensitivity (BRS) control of the heart rate is a key mechanism of blood pressure homeostasis, and is impaired in patients with hypertension. This study sought to assess the association between BRS and left ventricular morphology and function., Methods: We studied 224 hypertensive patients (125 men; aged 47.8 +/- 10.8 years, mean +/- SD) compared with 51 normotensive control subjects (25 men, aged 45.7 +/- 12.5 years). Left ventricular morphology, systolic and diastolic function were evaluated by echocardiography. Spontaneous BRS was measured using the sequence method., Results: BRS was inversely associated with relative wall thickness (R = 0.17; P < 0.0001) and left ventricular mass index (R = 0.03; P = 0.01); in particular, BRS was significantly impaired in patients with concentric left ventricular remodelling (median [interquartile difference] 9.4 [4.1]) and hypertrophy (9.05 [3.9]) compared with the normal left ventricle (12.3 [5]; P < 0.001). BRS showed a significant association with systolic function evaluated by midwall fractional shortening (r = 0.28; P < 0.001), stroke volume (r = 0.27; P < 0.001), stroke work (r = 0.17; P < 0.05), and fractional shortening (r = 0.17; P < 0.05). BRS was significantly decreased in patients with diastolic dysfunction; it was lower in patients with diastolic dysfunction compared with both the control group and hypertensive patients with normal diastolic function., Conclusion: BRS is associated with left ventricular morphology, systolic and diastolic function in hypertensive patients. In particular BRS is impaired in patients with diastolic dysfunction. These findings suggest a role for BRS as a target in arterial hypertension.

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

Background and Aim: Several epidemiological studies have suggested a link between low birth weight and coronary heart disease; this may be partly due to the association between low birth weight and conventional risk factors. Among the factors involved in the regulation of cardiovascular homeostasis, baroreflexes play a crucial role. The objective of the present study was to investigate if baroreflex sensitivity (BRS) in adulthood is associated with birth weight., Methods and Results: Two hundred and eleven adults from Turin, Italy, aged 22-24 years, were examined in a cross sectional survey. Birth weight, blood pressure, pulse rate, family history of hypertension, anthropometric and environmental parameters and spontaneous baroreflex sensitivity were evaluated. In this study we observed a significant increase in baroreflex sensitivity across the tertiles of birth weight, even after correction for gender, blood pressure and heart rate; in a regression model, birth weight was positively and independently associated with BRS; moreover, BRS showed a significant negative correlation with adult pulse rate., Conclusion: This finding may be helpful in understanding the association between low birth weight and cardiovascular disease outcome in later life, since baroreflex failure is associated with an increased cardiovascular morbidity and mortality.

Background: Most evidence currently favours a fundamental role of the autonomic nervous system in the pathogenesis of essential hypertension. Recent studies suggest that about 40% of baroreflex variation, an index of cardiac autonomic control, is influenced by genetic factors., Methods and Results: The aim of this study was to investigate the effect of a common polymorphic variant of the bradykinin B2 receptor gene (B2R; -58T/C) on the autonomic regulation of baroreflex sensitivity (BRS) in 129 mild-moderate never-treated hypertensive patients. No significant differences were found for clinical and biochemical parameters among genotypes. BRS increased with the number of B2R T alleles. B2R genotype was a strong independent predictor of BRS, accounting for 12% of its variation. We suggest that a decrease in the transcription of the bradykinin B2R gene in the presence of the B2R -58C allele could reduce BRS via the diminished effect of bradykinin., Conclusions: B2R genotype can explain part of the BRS variation that is unaccounted for by simple anthropometric variables and common risk factors.

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

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

The purpose of this study was to evaluate if changes in vascular properties were related to baroreflex function in patients with primary aldosteronism. Twenty-three patients with primary aldosteronism, 22 essential hypertensive patients and 16 normal controls were studied. Continuous finger blood pressure (BP) was recorded by Portapres device during supine rest and active stand up. Compliance was estimated from the time constant of pressure decay during diastole. Baroreflex sensitivity was calculated by autoregressive cross-spectral analysis of systolic BP and interbeat interval. The result was that baroreflex gain and compliance were lower in primary aldosteronism patients in the supine position (P = 0.002 and P < 0.05 respectively). Aldosterone plasma levels (R2 = 0.31, P = 0.01), age, systolic and diastolic BP, high and low frequency components of diastolic BP variability were independently related to compliance in primary aldosteronism. In conclusion primary aldosteronism is associated with an impaired baroreflex function related in part to a reduced arterial compliance. Despite a reduction of BP values and aldosterone levels, surgical or pharmacological treatment did not significantly change compliance values.

Aims/background: An impairment of baroreceptor sensitivity has been found in liver cirrhosis. Noninvasive and spontaneous estimates of baroreflex sensitivity are obtained from beat-to-beat blood pressure and heart rate recordings by means of cross-spectrum analysis and calculation of alpha-index (as a measure of baroreflex gain). The aim of the present study was to investigate the function of the spontaneous baroreflex sensitivity related to clinical Child score in liver cirrhosis., Methods: The alpha-index was evaluated in 40 cirrhotic patients (18 with and 22 without ascites) and 17 healthy subjects by analysing finger arterial pressure recorded noninvasively with the Portapres device., Results: Baroreflex sensitivity was significantly lower in cirrhotic patients with and without ascites compared with healthy subjects (p<0.01). Furthermore, in patients with ascites the baroreflex gain was significantly related to plasma sodium (p<0.01). A significant inverse relationship was present between baroreflex gain and grade of Child score and the severity of ascites (p<0.01). There were no significant relationships between hormonal parameters (catecholamines, renin, aldosterone, arginine-vasopressin, atrial natriuretic peptide and nitric oxide) and baroreflex gain. No significant differences were found between healthy subjects and cirrhotic patients with respect to systolic and diastolic blood pressure total variability in a supine position, whilst it was lower in cirrhotic patients with ascites in a tilted position (p<0.05)., Conclusion: Our findings showed that baroreflex sensitivity was significantly impaired in cirrhotic patients when compared with healthy subjects. In addition, there was a significant trend toward lower baroreflex sensitivity values with the grade score of Child class (p<0.01). Spectral analysis of the alpha-index provides viable alternatives to the pharmacological approach for estimation of baroreflex sensitivity and may represent a prognostic tool to identify cirrhotic patients at increased risk of adverse events.

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