Moderate Essential Hypertensive Patients Research Articles

An Open Label Parallel Group Study to Assess the Effects of Amlodipine and Cilnidipine on Pulse Wave Velocity and Augmentation Pressures in Mild to Moderate Essential Hypertensive Patients.

Hypertension is a major cardiovascular risk factor, which affects both large and small arteries. Because of the associated morbidity and mortality and the cost to society, it is an important public health challenge. Population based studies have reported that large artery stiffness is an important determinant of cardiovascular events and mortality in general population and in patients with hypertension. This study was designed to compare the effects of 8 weeks blood pressure control using Amlodepine and cilnidipine on haemodynamic parameters and vascular indices in mild to moderate hypertensive patients. A total of 60 patients were enrolled in the study. Thirty patients were randomly allocated to either Amlodipine 5 mg OD or Cilnidipine 10 mg OD for duration of eight weeks. Blood Pressure (BP), Heart Rate (HR), carotid-femoral Pulse Wave Velocity (cf PWV), Augmentation Index (AIx) and Aortic augmentation pressure (AoAP) were measured at baseline and at the end of eight weeks. The mean change in the central artery stiffness from baseline to week-8 in the Amlodipine group as compared to Cilnidipine group cf PWV -139.3±27.7 vs. -234.1±74.8 cm/s p=<0.0001, AoAP -3.8±1.5 vs. -5.6±3.3 mm of Hg p=0.008 and AIx -6.8±2.4 vs. -10.8±4.4 %, p=<0.0001 respectively. This study showed that the L/N-type calcium channel antagonist Cilnidipine has a similar antihypertensive action to Amlodipine, but is superior in improving the arterial stiffness.

ASSA14-11-05 Effects of Peridopril on Vascular Inflammation and Endothelium Function

Objective To explore the effects of peridopril on vascular inflammation and vascular endothelium function in mild to moderate essential hypertensive (EH) patients. Methods 140 EH patients were divided into peridopril group (70 cases) and conventional treatment group (70 cases). 70 cases of healthy volunteers were selected as a control group. We examined the blood express levels of high sensitivity C-reactive protein(hs-CRP), IL-6, ICAM-1, Fibrinogen C(FIB-C)and endothelium 1 (ET-1), nitric oxide (NO) levels and flow mediated dilatation (FMD) in brachial artery blood samples as well as angiotension before beginning treatment in each group, The peridopril group received a 4 mg tablet daily for 4 weeks. in addition to similar drug therapies as those in the conventional treatment group. Results All EH patients9 blood levels of hs-CRP, IL-6, ICAM-1, FIB-C and ET-1 increased significantly (all p Conclusions Peridopril tablet can inhibit vascular inflammation and protect the vascular endothelium function of EH patients. It is likely this plays an important role in the prevention of thrombotic diseases induced by hypertension.

Associations of Education with Blood Pressure in Hypertensive Patients: A Chinese Community Survey

Objective: To examine the association between education and blood pressure in hypertensive Chinese. Methods: A cross-sectional study was conducted at the health care center of a university affiliated hospital in 2008 to enroll 502 mild to moderate essential hypertensive patients. All participants completed a questionnaire addressing their sociodemographic information before they were given a routine physical check-up. Results: The baseline blood pressure was 151.87/95.76 mmHg for 277 females and 149.80/97.74 mmHg for 225 males. Only few women reported smoke (4%, n = 11) or drink alcohol (6.9%, n = 19). Over half of men smoke and drink (63.2% and 52.9% respectively). Alcohol consumption was found different among educational attainment groups in males. Correlation analyses demonstrated that education was inversely related to systolic blood pressure in female hypertensives. Conclusion: Education is associated with blood pressure in females.

Antihypertensive Efficacy and Safety of Olmesartan Medoxomil and Ramipril in Elderly Mild to Moderate Essential Hypertensive Patients With or Without Metabolic Syndrome

Two recent identically designed trials (one Italian and one European multinational) have compared the head-to-head efficacy and safety of the angiotensin II receptor blocker olmesartan medoxomil and the angiotensin converting enzyme inhibitor ramipril, in elderly patients with essential hypertension. The aim of the present study was to assess the antihypertensive efficacy of olmesartan and ramipril in elderly patients with hypertension, with or without metabolic syndrome, by performing a pooled analysis of data from the two head-to-head trials. After a 2-week, placebo wash-out, 1,453 treated or untreated elderly hypertensive patients aged 65-89 years [with sitting office diastolic blood pressure (DBP) 90-109 mmHg and/or sitting office systolic BP (SBP) 140-179 mmHg] were randomized to 12-weeks of double-blind treatment with olmesartan 10 mg or ramipril 2.5 mg once daily. Treatment could be up-titrated to 20 and 40 mg for olmesartan, and 5 and 10 mg for ramipril, after the first 2 and 6 weeks, respectively, in patients with inadequately controlled BP (BP ≥ 140/90 mmHg for non-diabetics and ≥ 130/80 mmHg for diabetics). Office BP was measured at randomization and after 2, 6 and 12 weeks of treatment. 24-h ambulatory BP recordings were obtained at randomization and after 12 weeks. Of the 1,426 patients in the intent-to-treat analysis, 735 (51.5 %) had metabolic syndrome (olmesartan, n = 372; ramipril, n = 363). After 12 weeks of treatment, baseline-adjusted office BP reductions were greater (p < 0.05) with olmesartan (SBP 17.0 mmHg; 95% CI 18.4, 15.6; DBP 9.6 mmHg; 95% CI 10.4, 8.8) than with ramipril (SBP 14.7 mmHg; 95% CI 16.1, 13.2; DBP 8.4 mmHg; 95% CI 9.2, 7.6) in patients with metabolic syndrome. In these patients, BP normalization rates were also greater with olmesartan than with ramipril (46.0 vs. 35.8%, p < 0.01). Similarly, in patients without metabolic syndrome, the antihypertensive efficacy of olmesartan was also significantly (p < 0.05) better than that of ramipril. In the subgroup of patients with valid ambulatory BP (ABP) recordings and metabolic syndrome (olmesartan, n = 182; ramipril, n = 170), the reduction in mean 24-h ABP was greater with olmesartan (SBP 10.2 mmHg; 95% CI 11.8, 8.6; DBP 6.6 mmHg; 95% CI 7.5, 5.6) than with ramipril (SBP 8.5 mmHg; 95% CI 10.2, 6.9; DBP 4.7 mmHg; 95% CI 5.7, 3.7), with a statistically significant (p < 0.01) difference for the DBP comparison. The proportion of patients experiencing drug-related adverse events was comparable in patients with (olmesartan 2.4 % vs. ramipril 2.8 %) and without (3.5 vs. 3.7 %) metabolic syndrome. Olmesartan provides more effective BP control than ramipril in elderly hypertensive patients with and without metabolic syndrome.

The effects of peridopril on vascular inflammation and vascular endothelium function in mild- to- moderate essential hypertensive patients

ObjectiveTo explore the effects of peridopril tablet on vascular inflammation and vascular endothelium function in mild- to- moderate essential hypertensive (EH) patients.Methods100 EH patients were divided into peridopril group (50...

Collection and analysis of parameters drawn from cardiovascular system in hypertensive patients during sexual activity

ObjectiveTo study the response of cardiovascular parameters during sexual activity and analyse the cardiovascular effect of sexual activity in hypertensives as part of the study ‘Cardiovascular Effect of Sexual Activity...

Open label, Randomized, Active drug comparative, Parallel group, Multi-center, Phase IV Study to Compare the Effect of Benidipine and Losartan on Arterial Stiffness and Central Blood Pressure in Mild to Moderate Essential Hypertensive Patients (BELASCO Trial)

Open label, Randomized, Active drug comparative, Parallel group, Multi-center, Phase IV Study to Compare the Effect of Benidipine and Losartan on Arterial Stiffness and Central Blood Pressure in Mild to Moderate Essential Hypertensive Patients (BELASCO Trial)

Blood pressure levels, left ventricular mass and function are correlated with left atrial volume in mild to moderate hypertensive patients

Arterial hypertension is associated with an increased risk of atrial fibrillation (AF), and leads to a pronounced increase in morbidity and mortality. Left atrial volume (LAV) is an important prognostic marker in the older populations. The aim of our study was to identify the clinical and echocardiographic determinants of LAV in middle-aged (<70 years old) essential hypertensive patients.We evaluated cardiac structure and function in 458 patients, 394 treated and untreated mild to moderate essential hypertensives patients (mean+/-s.d. age 48.4+/-11.1 years) with no associated clinical condition and 64 normotensive control participants (age 45.7+/-12.8 years; P=0.12). A multivariate analysis was performed to calculate the relative weight of each of the variables considered able to predict LAV. The LAV index (LAVi) was significantly increased in the essential hypertensive group vs the control group and was significantly dependent on blood pressure levels (SBP and DBP, P<0.05 for both) and body mass index (BMI) (P<0.0001). Considering the left ventricular (LV) variables, the LV mass index (LVMI) (R(2)=0.19, P<0.001) and LAV were increased in essential hypertensive patients with left ventricular hypertrophy (LVH), and patients with enlarged LAV showed lower systolic and diastolic function and an increased LVMI. The LAVi is dependent on blood pressure levels and anthropometric variables (age and BMI). Further structural (LVMI) and functional (systolic and diastolic) variables are related to the LAVi; LVMI is the most important variable associated with LAV in mild to moderate essential hypertensive adult patients. These findings highlight the importance of left atrium evaluation in adult, relatively young, essential hypertensive patients.

Randomized, Double-blinded Trial Evaluation of Valsartan/Hydrochlorothiazide Combination Therapy in Mild to Moderate Essential Hypertension in North-east China

In this randomized, double-blind study, 126 mild to moderate essential hypertensive patients from northern China were studied to determine the efficacy and safety of a combination therapy of valsartan and hydrochlorothiazide. Patients were randomized to the V80/H12.5 (80 mg valsartan/12.5 mg hydrochlorothiazide) group or the V80 (80 mg valsartan) group. Six weeks after treatment, the mean decrease from baseline in mean sitting systolic blood pressure (MSSBP) was significantly higher in the V80/H12.5 group than the V80 group, but there was no difference in the change of mean sitting diastolic blood pressure (MSDBP) in the two groups. Overall, 80.33% and 70.97% had a controlled response (normalized MSDBP), and 85.25% and 77.42% had a diastolic response (normalized MSDBP or > 10 mmHg reduction in MSDBP) in the V80/H12.5 and V80 groups, respectively (not significantly different). The incidence of adverse events was also similar between the two groups. The combination of 80 mg valsartan/12.5 mg hydrochlorothiazide was efficacious and well tolerated in mild and moderate essential hypertensive patients.

Multifocal Electroretinogram in Mild to Moderate Essential Hypertension

Purpose. To investigate the local retinal dysfunctions in mild to moderate essential hypertensive patients by using multifocal electroretinogram (mfERG). Methods. Thirty-one patients with stage 1 or stage 2 hypertension (HT) and 31 age- and sex-matched healthy normotensive (NT) subjects were included. Fourteen of the patients had stage 1 and 17 had stage 2 hypertension. Twenty had grade 1 and 11 had grade 2 hypertensive retinopathy. The local retinal functions from the fovea to the peripheral 30 degrees were evaluated by multifocal electroretinogram by dividing this area to central hexagonal area (CH) and four concentric rings around the central hexagon (Rings 1–4). The amplitude and the implicit times of the positive peak (P1) and the negative peak (N1) of the responses were compared between the control subjects and hypertensive patients. Only the right eyes were included. The differences between the hypertensive patients and control subjects were investigated using independent samples t test, and the differences between grade 1 and grade 2 hypertensive retinopathy and stage 1 and stage 2 hypertension were investigated using Mann-Whitney U test. Results. P1 amplitudes in CH (HT: 129.0 ± 29.5, NT: 149.1 ± 45.5, p = 0.043) and in Ring 3 (HT: 37.0 ± 8.0, NT: 41.7 ± 7.8, p = 0.024) and N1 amplitude in Ring 1 (HT: 26.8 ± 7.4, NT: 30.8 ± 7.8, p = 0.048) in the hypertensive patients was significantly reduced when compared to healthy normotensive subjects. There was no significant difference in terms of P1 and N1 implicit times. There was also no significant difference between the patients with stage 1 or stage 2 hypertension and patients with grade 1 or grade 2 hypertensive retinopathy. Conclusion. Hypertensive subjects have local retinal dysfunctions with respect to healthy controls. This result probably originated from retinal ischemia due to changes in retinal and/or choroidal circulation in systemic arterial hypertension.

Different relation between 24-h blood pressure and distensibility at different peripheral arteries. Data from the European Lacidipine Study on Atherosclerosis (ELSA)

The European Lacidipine Study on Atherosclerosis (ELSA) has been planned to investigate the effect of reduction in office and ambulatory blood pressure by lacidipine versus atenolol on carotid artery wall thickness in mild to moderate essential hypertensive patients with no metabolic abnormalities. One prespecified sub-study of ELSA focused on measurements of arterial distensibility in the carotid as well as in the radial artery to determine the relationship of functional arterial properties with office versus ambulatory blood pressure (BP) values as well as the correspondence between functional and structural arterial alterations. The sub-study was conducted on 124 patients recruited in four centres (Monza-Milan, Paris, Grenoble and Glasgow). BP was measured both by a mercury sphygmomanometer and by 24-h ambulatory monitoring. Common carotid artery wall thickness was measured by certified sonographers as described in the main study. Common carotid and radial artery distensibility were obtained by echotracking techniques, which allowed to relate changes in arterial diameter with systo-diastolic BP changes. Carotid artery wall distensibility showed (1) a negative correlation with office and more so 24-h average systolic BP (r = -0.45 and -0.58, P < 0.008 and 0.001) but not with office or 24-h diastolic BP) and (2) a negative correlation with the corresponding wall thickness (r = -0.47, P < 0.005). In contrast, at the radial artery level distensibility and thickness showed no correlation with each other and with BP. Carotid (but not radial) artery distensibility also correlated with ambulatory systolic BP variability but the correlation was lost after adjustment for age and mean BP values. These data suggest that stiffening of large elastic artery is reflected more by ambulatory than office BP elevations, systolic BP being much more important than diastolic. Alterations of large elastic arteries function is related to structural wall changes. Functional and structural properties of middle-size muscle arteries are independent of BP.

Transvascular albumin leakage and forearm vasodilatation to acetylcholine in essential hypertension

The impact of hypertension on microvascular permeability and nitric oxide-mediated endothelial vasomotion in humans has been studied by measuring either the transcapillary albumin escape rate (TERalb, a measure of permeability through systemic capillary endothelium where most of the albumin permeation takes place) and forearm vasodilatation to locally infused acetylcholine (used as a probe for the nitric oxide-releasing potential of arteriolar endothelial cells). It is unknown, however, how the two parameters relate to each other in the same hypertensive subject. This piece of evidence may enhance our understanding about the relative effect of hypertension on two biological functions (ie, permeability and nitric oxide-mediated vasomotion), both dependent on vascular endothelium, and also may allow to appreciate in greater detail the profile of parameters frequently used as markers of microvascular dysfunction in human hypertension. For these reasons, TERalb (the 1-h decline rate of intravenous 125I-albumin) and forearm vasodilatation (strain gauge venous plethysmography) to graded intraarterial acetylcholine infusion were measured in 44 never-treated men with uncomplicated essential hypertension, and 15 male normotensive controls with comparable age, lipids, and proportion of current smokers. TERalb was increased in patients, whereas acetylcholine-mediated vasodilatation did not differ significantly between the two groups, indicating a heterogeneous impact of elevated blood pressure on capillary permeability and endothelial vasomotion in still uncomplicated mild to moderate essential hypertensive patients. The dissociation between TERalb and forearm responsiveness to acetylcholine also demonstrates that different endothelial-dependent biologic parameters do not behave uniformly in human hypertension.

Use of electronic pill boxes to assess risk of poor treatment compliance: Results of a large-scale trial

The objective of the present study was to determine the predictive factors of treatment compliance in hypertensive patients. This was an open large-scale multicenter study where mild to moderate essential hypertensive patients received trandolapril (2 mg) once daily for 30 to 60 days in addition to their usual treatment. Trandolapril was packed in electronic pill boxes that registered date and time of each opening. The main compliance parameters were the percentage of missed doses, the percentage of delayed doses, and the percentage of correct dosing periods. Predictive factors of poor compliance (correct dosing periods <80%) were determined using a multivariate stepwise logistic regression analysis. Two thousand one hundred seventy-three patients aged 60 ± 12 years were analyzed. Of the total patients 37% were poor compliers; 29% of patients forgot more than 10% of doses and 36% of patients delayed more than 10% of doses. Ranked predictive factors of poor compliance were: age <60 years (odds ratio [OR], 1.80 [1.49 to 2.17], P = .0001), the Paris area (OR, 1.70 [1.32 to 2.19], P = .0001), smokers (OR, 1.65 [1.29 to 2.11], P = .0001), monotherapy (OR, 1.40 [1.14 to 1.72], P = .0012), and baseline diastolic blood pressure ≥100 mm Hg (OR, 1.21 [1.01 to 1.46], P = .044). Therefore, we conclude that young hypertensives, large city dwellers, and smokers are more likely to be poor compliers. The presence of some of these characteristics might incite the physician either to encourage patient compliance or to prescribe antihypertensive drugs that have an effect that persists even beyond 24 h.

Distribution of 24-H ambulatory diastolic BP and heart rate in six decades of mild to moderate essential hypertensive patients

Distribution of 24-H ambulatory diastolic BP and heart rate in six decades of mild to moderate essential hypertensive patients

Effect of chronic angiotensin converting enzyme inhibition on sympathetic nerve traffic and baroreflex control of the circulation in essential hypertension.

Human studies have shown that the blood pressure lowering effects of angiotensin converting enzyme inhibitors are accompanied by a reduction in plasma norepinephrine levels. Whether this is due to central or peripheral mechanisms is unknown, however. To evaluate the effects of chronic interference with the renin-angiotensin system on sympathetic nerve traffic and baroreflex control of vagal and adrenergic cardiovascular drive. In 18 untreated mild to moderate essential hypertensive patients aged 48.5+/-1.9 years (mean+/-SEM), we measured mean arterial pressure (Finapres), heart rate (electrocardiogram), plasma renin activity (radioimmunoassay), plasma norepinephrine (high-performance liquid chromatography) and postganglionic muscle sympathetic nerve activity (microneurography at a peroneal nerve). In nine patients, measurements were performed before and after 2 months of oral administration of lisinopril (10 mg/day), while in the remaining nine patients they were performed before and after a 2 month observation period, without the drug administration. Measurements were performed at rest and during baroreflex stimulation and deactivation elicited by stepwise intravenous infusions of phenylephrine and nitroprusside, respectively. Lisinopril induced a marked increase in plasma renin activity (from 1.1+/-0.2 to 6.4+/-1.3 ng/ml per h, P< 0.01) and a reduction in mean arterial pressure (from 109.6+/-3.1 to 98.7+/-2.9 mmHg, P < 0.01) without affecting the heart rate. Plasma norepinephrine and muscle sympathetic nerve activity values were not significantly different before and after lisinopril treatment (plasma norepinephrine values changed from 290.4+/-39.2 to 308.1+/-67.1 pg/ml; muscle sympathetic nerve activity changed from 56.4+/-5.3 to 50.6+/-6.6 bursts/100 heart beats). Neither the sympathoinhibitory nor the sympathoexcitatory responses to phenylephrine and nitroprusside were affected by lisinopril, nor the concomitant bradycardia and tachycardia. The curves relating mean arterial pressure to heart rate and muscle sympathetic nerve activity values during baroreceptor manipulation were shifted to the left, indicating a resetting of the baroreflex to the lower blood pressure values achieved during treatment. CONCLUSIONS In essential hypertension, sympathetic nerve traffic is not affected by chronic angiotensin converting enzyme inhibitor treatment that effectively interferes with the renin-angiotensin system and lowers the elevated blood pressure. The baroreflex ability to modulate heart rate and central sympathetic outflow is also unaffected. These data argue against the existence of a central sympathoexcitatory effect of angiotensin II in this condition. They also indicate that antihypertensive treatment with an angiotensin converting enzyme inhibitor preserves autonomic reflex control, with favorable consequences for cardiovascular homeostasis.

Differential Response in Left Ventricular Mass and Arterial Resistive Index following Fosinopril Therapy

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

Proximal Tubular Function in Essential Hypertensives on Beta-blocker Therapy with Atenolol

Krusell LR, Jespersen LT, Christensen CK, Thomsen K, Pedersen OL. Proximal tubular function in essential hypertensives on beta-blocker therapy with atenolol.Renal plasma flow (RPF) and glomerular filtration rate (GFR) were measured during waterloading and constant infusion of [131I]hippuran and [125I]iothalamate in 24 mild to moderate essential hypertensive patients before and after 3.5 months treatment with atenolol. Clearances of sodium and potassium were measured 2–3 hours post-dosing and renal vascular resistance (RVR) and filtration fraction (FF) were calculated. Measurement of clearance of lithium (CLi) and uric acid (Curic acid) was employed to investigate specifically proximal tubular function.Beta-blockade with atenolol produced a borderline significant decrement in RPF but no change in GFR, RVR and FF. There was a significant reduction in CLi fractional proximal escape of sodium and water, Curic acid and an increase in absolute proximal reabsorption of sodium, indicating an inhibition of proximal tubular function. The distal tubular parameters exhibited changes tending to normalize excretion of sodium, but not water. Changes in RVR were inversely related to changes in CLi and Curic acid suggesting unopposed alfa-adrenergic stimulation to be implicated in the renal counterregulation at a proximal tubular site following long-term administration of atenolol in essential hypertension.

The Effects of Amlodipine on Left Ventricular Mass and Diastolic Function in Concentric and Eccentric Left Ventricular Hypertrophy.

BACKGROUND: The effects of the antihypertensive therapy with amlodipine (5-10 mg/day) on left ventricular mass and diastolic function were examined in 30 mild to moderate essential hypertensive patients who have left ventricular hypertrophy (LVH) and diastolic dysfunction. METHODS AND RESULTS: Each patient's left ventricular mass was measured, and left ventricular diastolic function was assessed by echocardiographic Doppler examination at entry, and at 3 and 6 months after the initiation of the treatment. Amlodipine reduced both blood pressure (from 164 +/- 14/104 +/- 6 mmHg to 134 +/- 9/83 +/- 4 mmHg) and left ventricular mass index (from 160 +/- 30 g/m(2) to 137 +/- 26 g/m(2)) significantly at 3 months and both parameters maintained at these levels for 6 months. When the patients were classified according to the type of the LVH, a significant regression in left ventricular mass index was seen only in the patients who had concentric LVH was a relative wall thickness >/=0.44 (n = 16), but not in the eccentric LVH group (n = 14), although both groups were not significantly different from each other regarding the basal hemodynamic parameters, baseline left ventricular mass index and the decrease in blood pressure in response to amlodipine treatment. The mitral inflow E/A ratio did not show any significant change in either group. CONCLUSIONS: Amlodipine produced significant regression in LVH only in the patients with concentric LVH, but not those with eccentric LVH, while it did not change the diastolic dysfunction. Therefore, the type of LVH seems to be an important feature in determining the effects of antihypertensive treatment on left ventricular mass index.

Effects of aging on 24-h dynamic baroreceptor control of heart rate in ambulant subjects

The effects of aging on the dynamic modulation of baroreflex sensitivity over 24 h was assessed in eight elderly (mean age +/- SD, 63.9 +/- 3.2 yr) and in eight young (23.9 +/- 6.1 yr) mild or moderate essential hypertensive patients, who were subject to a 24-h intra-arterial (Oxford technique) blood pressure recording in ambulatory conditions. The sensitivity of baroreflex control of the heart rate was dynamically assessed by quantifying 1) the slope of the regression line between pulse interval (the reciprocal of heart rate) and systolic blood pressure changes over spontaneously occurring hypertension-bradycardia or hypotension-tachycardia sequences (time domain analysis) and 2) the ratio between spectral-powers of pulse interval and systolic blood pressure around 0.1 Hz (alpha-coefficient: frequency domain analysis). The 24-h average sequence slope was lower in old than in young individuals (4.4 +/- 0.5 vs. 9.9 +/- 1.3 and 4.8 +/- 0.7 vs. 8.4 +/- 1.4 ms/mmHg for hypertension-bradycardia and hypotension-tachycardia sequences, respectively; P < 0.05 for both). Similar results were obtained by using the alpha-coefficient approach. The marked nighttime increase in baroreflex sensitivity observed in young individuals was much less evident in the elderly. Thus 24-h baroreflex sensitivity is markedly impaired by aging. The impairment becomes manifest also as an inability to increase baroreflex sensitivity at night.

Forearm blood flow reserve and cardiac and renal indexes of pressure load in normotensive and hypertensive individuals.

In response to hypertension, arterioles remodel their structure, the heart develops myocardial hypertrophy, and the kidney reduces creatinine clearance and increases albuminuria. To better understand the interrelations among the target organs involved in hypertension, we evaluated minimal forearm vascular resistances--a hemodynamic index of arteriolar structure derived from mean blood pressure and maximal postischemic forearm blood flow--the echocardiographic indexes of cardiac structure, and urinary albumin excretion and creatinine clearance in 29 male mild to moderate non-macroalbuminuric essential hypertensive patients on no drugs and 11 age- and sex-matched normotensive control subjects. Minimal forearm resistances were elevated in hypertensive patients and correlated with left ventricular mass, wall thickness, and mean arterial pressure. Patients with abnormal minimal forearm resistances (2 SD above normal) were characterized by higher pressure, greater wall thickness, lower creatinine clearance, and higher albumin excretion, suggesting that maximal forearm flow capacity does relate to the hemodynamic load exerted on both the kidney and heart. However, the correlation with cardiac structure and mean arterial pressure explained only part of the variability of minimal forearm resistances. Furthermore, no correlation among these parameters was found when hypertensive patients were evaluated separately from normotensive subjects, possibly because of heterogeneous factors active on arteriolar structure and unrelated to the pressor load. Overall, the data suggest that the development of abnormal minimal forearm resistances in the course of the hypertensive process is related to the pressor load, but its details need further understanding.