首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 36 毫秒
1.
International guidelines recommend that antihypertensive drug therapy should normalize not only diastolic (DBP) but also systolic blood pressure (SBP). Therapeutic trials based on cardiovascular mortality have recently shown that SBP reduction requires normalization of both large artery stiffness and wave reflections. The aim of the present study was to compare the antihypertensive effects of the very-low-dose combination indapamide (0.625 mg) and perindopril (2 mg) (Per/Ind) with the beta-blocking agent atenolol (50 mg) to determine whether Per/Ind decreases SBP and pulse pressure (PP) more than does atenolol and, if so, whether this decrease is predominantly due to reduction of aortic pulse wave velocity (PWV) (automatic measurements) and reduction of wave reflections (pulse wave analysis, applanation tonometry). In a double-blind randomized study, 471 patients with essential hypertension were followed for 12 months. For the same DBP reduction, Per/Ind decreased brachial SBP (-6.02 mm Hg; 95% confidence interval, -8.90 to -3.14) and PP (-5.57; 95% confidence interval, -7.70 to -3.44) significantly more than did atenolol. This difference was significantly more pronounced for the carotid artery than for the brachial artery. Whereas the 2 antihypertensive agents decreased PWV to a similar degree, only Per/Ind significantly attenuated carotid wave reflections, resulting in a selective decrease in SBP and PP. The very-low-dose combination Per/Ind normalizes SBP, PP, and arterial function to a significantly larger extent than does atenolol, a hemodynamic profile that is known to improve survival in hypertensive populations with high cardiovascular risk.  相似文献   

2.
OBJECTIVE: In hypertension, blockade of the renin-angiotensin system reduces left ventricular mass (LVM) independently of brachial systolic (S), diastolic (D), and mean (M) blood pressure (BP). From central to peripheral arteries, MBP and DBP are practically unchanged, whereas SBP and pulse pressure (PP) increase significantly. The objective was to determine whether changes in LVM under drug treatment was preferentially associated with changes in central or brachial SBP and PP. DESIGN: A substudy of 146 subjects was selected from 469 hypertensive patients submitted to a double-blind randomized trial comparing the combination of perindopril (2 mg; Per) and indapamide (0.625 mg; Ind) with atenolol (50 mg, one tablet per day). MAIN OUTCOME MEASURES: Before and after 1 year of treatment: LVM (echocardiography) in 146 subjects and, in 52 of them, central (carotid) BP and timing of wave reflections (tonometry). RESULTS: LVM changes were significantly associated with antihypertensive treatment, with lower LVM with Per/Ind than with atenolol. Changes in SBP and PP, but not in MBP and DBP, were more significantly associated with Per/Ind than with atenolol, with more pronounced effects using central than brachial measurements, and a longer delay in central return of wave reflections under Per/Ind. In the sampling of 52 patients with tonometry, the change in LVM between the two drug regimens was significantly linked to central, but not brachial, PP change. CONCLUSIONS: This observational study shows a lower LVM under Per/Ind than under atenolol. The greater change in LVM on Per/Ind was linked to central and not brachial blood pressure.  相似文献   

3.
BACKGROUND : Dose-ranging of antihypertensive agents have been done to optimize diastolic blood pressure (DBP) reduction, but with little information on systolic (SBP), mean (MBP), or pulse (PP) pressures. A low-dose combination of perindopril (Per) and indapamide (Ind) has been shown to reduce more SBP than atenolol for the same DBP reduction. However, the possible influence of gender on this finding has never been tested. PURPOSE : A database of five randomized, double-blind, dose-ranging studies was established to determine the optimal dose of the Per/Ind combination in hypertensive men and women. A total of 2907 patients were treated by either placebo or various combinations associating Per (2, 4, 8 mg) and Ind (0.625, 1.25, 2.5 mg). RESULTS : In the overall population, there was a significant dose-response relationship (P < 0.001) for doubling the dose of Per 2/Ind 0.625 mg up to Per 8/Ind 2.5 mg with a progressive fall in SBP, DBP, MBP. When men and women were analyzed by dose, SBP, DBP and MBP (but not PP) decreased significantly more in women than in men until the Per 4/Ind 1.25 dosage was reached. Thereafter, with higher dosages, generating a slight but significant hypokalemia, the finding was reversed, resulting in a gender interaction in the overall population. CONCLUSION : In hypertensive subjects, the low-dose combinations Per 2/Ind 0.625 and Per 4/Ind 1.25 are the most effective in reducing blood pressure and avoiding hypokalemia. This effect is more pronounced in women, in which increased SBP and PP are predominant hemodynamic features.  相似文献   

4.
BACKGROUND: International recommendations have classified brachial blood pressure (BP) in subgroups enabling better cardiovascular risk stratification. Central BP is an independent predictor of cardiovascular risk, differing from brachial BP through the predominant influence of arterial stiffness and wave reflections. Central BP has never been studied in relation to international guidelines for brachial BP classification. METHODS: In 580 chronically treated hypertensive subjects we measured: carotid-femoral pulse wave velocity (PWV), carotid artery augmentation index (AI) and carotid blood pressures, using applanation tonometry and pulse wave analysis, and using brachial BP for carotid pressure wave calibration. RESULTS: For each given brachial value, carotid systolic blood pressure (SBP) and PP were significantly lower than the corresponding brachial SBP and PP. This pressure amplification was significantly lower in the 'optimal' and 'normal' BP ranges (6.8-7.4 mmHg) than in the higher BP ranges (10.1-11.3 mmHg), mainly depending on heart rate (HR) and PWV levels. PWV gradually increased as a function of brachial BP classification and was a significant predictor of this classification independently of age, drug treatment, atherosclerotic lesions and even mean BP. Finally, PWV was a highly sensitive marker of the effective BP control throughout all decades of age. CONCLUSION: Under chronic antihypertensive therapy, central BP does not strictly parallel the corresponding brachial BP classification, depending on differences in aortic stiffness and HR. Whether aortic PWV might predict the brachial BP classification and/or the presence of effective BP control, as suggested in this study, needs further confirmation.  相似文献   

5.
A comparison of atenolol and nebivolol in isolated systolic hypertension   总被引:1,自引:0,他引:1  
OBJECTIVES: Some beta-blockers are less effective in reducing central blood pressure than other antihypertensive drugs, which may explain the higher rate of events in subjects randomized to atenolol in recent trials. We hypothesized that nebivolol, a mixed beta-blocker/nitro-vasodilator, would be more effective than atenolol in reducing central blood pressure and augmentation index (AIx). The aim of the present study was to test this in a double-blind, randomized, cross-over study, in a cohort of subjects with isolated systolic hypertension. METHODS: Following a 2-week placebo run-in, 16 never-treated hypertensive subjects received atenolol (50 mg), nebivolol (5 mg) and placebo, each for 5 weeks, in a random order. Seated brachial blood pressure and heart rate were measured. Aortic blood pressure, AIx and pulse wave velocity (PWV) were assessed non-invasively. RESULTS: The placebo-corrected fall in brachial pressure was similar between nebivolol and atenolol, as was the reduction in PWV (mean change +/- SEM: -1.0 +/- 0.3 and -1.2 +/- 0.2 m/s; P = 0.2). However, there was less reduction in heart rate (-19 +/- 2 versus -23 +/- 2 beats/min; P < 0.01) and increase in AIx (+6 +/- 1 versus +10 +/- 1%; P = 0.04), following nebivolol. Aortic pulse pressure was significantly lower (50 +/- 2 versus 54 +/- 2 mmHg; P = 0.02) after nebivolol. N-terminal pro-B-type natriuretic peptide (proBNP) rose on both drugs (100 +/- 33 versus 75 +/- 80 pg/ml; P < 0.01 for both, NS for comparison). CONCLUSIONS: Nebivolol and atenolol have similar effects on brachial blood pressure and aortic stiffness. However, nebivolol reduces aortic pulse pressure more than atenolol, which may be related to a less pronounced rise in AIx and bradycardia. Whether this will translate into differences in clinical outcome requires further investigation.  相似文献   

6.
BACKGROUND: There is conflicting information with regard to the effect of beta-blockers on arterial stiffness and wave reflection. We compared a vasodilating beta-blocker, nebivolol, with atenolol. METHODS: We randomized 40 subjects with untreated hypertension (mean +/- s.e.m. systolic/diastolic blood pressure (BP) of 160 +/- 3/98 +/- 1 mm Hg, age 49 +/- 1 years) 16 of whom were women, to atenolol 50 mg or nebivolol 5 mg daily for 4 weeks. Arterial stiffness was assessed in terms of carotid-femoral pulse wave velocity (PWV, Complior) and arterial wave reflection (augmentation index (AIx) by applanation tonometry, Sphygmocor). RESULTS: Both beta-blockers produced an equal reduction in brachial BP but aortic pulse pressure (PP) was reduced to a greater extent by nebivolol (P < 0.05). PWV was decreased significantly by both therapies (nebivolol: from 11.5 +/- 0.5 to 9.9 +/- 0.5 m/s; atenolol: from 11.1 +/- 0.4 to 9.8 +/- 0.4 m/s; P < 0.01) but only nebivolol significantly reduced AIx (from 35 +/- 5 to 28 +/- 2%, P < 0.05). In addition, whereas PP amplification (PP, mm Hg) decreased with atenolol therapy (from 10 +/- 1 to 7 +/- 1, P < 0.01), it increased with nebivolol therapy (from 8 +/- 1 to 14 +/- 3, P < 0.01). Atenolol reduced heart rate to a greater extent than nebivolol did (14 +/- 3/min reduction by atenolol vs. 8 +/- 2/min reduction by nebivolol, P < 0.05). There was no difference between the two treatments in respect of the effect on transit time. CONCLUSION: The beta-blockers, atenolol and nebivolol, have a similar effect in reducing arterial stiffness in the large elastic aorta, largely secondary to BP reduction. Nebivolol, in contrast to atenolol, has an effect on small muscular arteries, increasing PP amplification and reducing wave reflection, possibly because of increased levels of nitric oxide (NO). Such ancillary properties may impart important distinct hemodynamic effects, and therefore beta-blockers cannot be regarded as a homogeneous group.  相似文献   

7.
OBJECTIVES: The ESH2003 report (J Hypertens 2003, 21:1011-1053) has classified brachial blood pressure into six groups reflecting the consistently increasing cardiovascular risk caused by high blood pressure. Chronically treated hypertensive individuals with well-controlled blood pressure retain higher cardiovascular risk than normotensive untreated individuals. Differences between these groups in arterial stiffness, pressure wave reflections and central blood pressure, which are all predictors of cardiovascular risk independently of peripheral blood pressure, have never been studied. METHODS: A cohort of 216 treated subjects with controlled hypertension was compared with 105 never-treated normotensive controls, according to the ESH2003 blood pressure groups. Aortic stiffness (pulse wave velocity; PWV), carotid wave reflections (augmentation index; AI) and carotid pressures were measured non-invasively, by pulse wave analysis. Systolic blood pressure (SBP) and pulse pressure (PP) amplification between brachial and carotid arteries were estimated. RESULTS: The distribution of subjects in each subgroup of the untreated and treated populations was: 'optimal', 21 versus 43; 'normal', 44 versus 77; 'borderline', 40 versus 96. Brachial blood pressure, carotid SBP and PP did not differ between the two populations, but a constant interaction between blood pressure classification and treatment effect on PWV, AI and blood pressure amplification was found. Compared with untreated subjects, treated subjects had higher AI and lower blood pressure amplification (in the optimal group) and higher PWV (in the borderline group). CONCLUSION: 'Optimal' to 'borderline' blood pressure control in chronically treated hypertensive individuals is associated with impaired properties of the large and small arteries. These results suggest that antihypertensive treatment strategies with more beneficial effects on arterial properties are needed.  相似文献   

8.
The VASOTENS Registry is an international telehealth‐based repository of 24‐hour ambulatory blood pressure monitorings (ABPM) obtained through an oscillometric upper‐arm BP monitor allowing combined estimation of some vascular biomarkers. The present paper reports the results obtained in 1200 participants according to different categories of CV risk. Individual readings were averaged for each recording and 24‐hour mean of brachial and aortic systolic (SBP) and diastolic blood pressure (DBP), pulse wave velocity (PWV), and augmentation index (AIx) obtained. Peripheral and central BP, PWV and AIx values were increased in older participants (SBP only) and in case of hypertension (SBP and DBP). BP was lower and PWV and AIx higher in females. PWV was increased and BP unchanged in case of metabolic syndrome. Our results suggest that ambulatory pulse wave analysis in a daily life setting may help evaluate vascular health of individuals at risk for CV disease.  相似文献   

9.
目的:探讨高血压病患者脉搏波传导速度(PWV)与动态血压(ABPM)各指标的相关性。方法:对200例高血压病患者按年龄分为非老年高血压患者(年龄60岁)和老年高血压患者(年龄≥60岁)两组;每组中再按PWV正常值分为9 m/s和≥9 m/s两组。收集相关临床资料,测量身高、体质量、腰围、臀围,检测PWV和ABPM,计算24 h平均脉压(PP)、脉压指数(PPI)、体质量指数(BMI)、腰臀比(WHR),分析ABPM的各值及其他有关因素与PWV的相关性。结果:与非老年高血压病患者比较:老年高血压病患者WHR、PP、PPI、PWV显著升高(P0.05,P0.01);这两组中PWV≥9 m/s的患者,SBP、DBP、PP、PPI均高于同组内PWV9 m/s的患者,组内比较有显著差异性(P0.05,P0.01);经Pearson相关分析:PPI与PWV相关系数r值(0.501)大于SBP、DBP、PP的r值(0.398、-0.251、0.418)。结论:高血压病患者PPI与PWV密切相关,在反映大动脉硬化程度上PPI优于动态血压其他指标。  相似文献   

10.
BACKGROUND: Circadian blood pressure (BP) measurements provide more information on hypertensive complications than office BP measurements. The purpose of this study was to analyze the efficacy of the first-line combination of perindopril 2 mg plus indapamide 0.625 mg versus atenolol 50 mg on BP parameters and variability over 24 h in patients with hypertension. METHODS: A double-blind, randomized, controlled, 12-month study comparing perindopril/indapamide and atenolol was performed in 201 patients (age 55.0 years) with uncomplicated sustained essential hypertension. Ambulatory BP measurements (ABPM) were done every 15 min over 24 h. RESULTS: After 1 year of treatment, the decrease in systolic BP was significantly greater for perindopril/indapamide than for atenolol during the entire 24-h period (-13.8 v -9.2 mm Hg), the daytime and the nighttime periods (P <.01). Diastolic blood pressure (DBP) variations were comparable for the two groups (-7.2 v -8.3 mm Hg, NS). Pulse pressure (PP) reduction was also significantly greater for perindopril/indapamide than for atenolol (for the whole 24 h, -6.6 v -0.9 mm Hg, P <.001). The through to peak (T/P) BP ratio and the smoothness index were comparable in the two groups for DBP. For systolic blood pressure (SBP), higher values of the T/P ratio (0.80 v 0.59) and the smoothness index (1.45 v 0.98; P <.02) were achieved for the perindopril/indapamide combination than for atenolol. CONCLUSIONS: The perindopril/indapamide first-line combination decreased SBP and PP more effectively than atenolol. Moreover, the BP control effect was smooth and consistent throughout the 24-h dosing interval and BP reduction variability was lower than the one induced by atenolol.  相似文献   

11.
OBJECTIVE: Increased arterial stiffness is a determinant of cardiovascular mortality. Pulse wave velocity (PWV) is a direct measure of arterial stiffness. Aortic augmentation index (AI) and pulse pressure (PP) are surrogate measures of arterial stiffness. Both PWV, AI and PP increase with cardiovascular risk factors. The aim of this study was to test the validity of AI and PP as surrogate measures of arterial stiffness compared with PWV, during beta-adrenergic stimulation with Isoprenaline (Iso). DESIGN AND METHODS: A total of 41 healthy volunteers entered a randomized, double-blind, placebo-controlled, cross-over study. In random order, subjects were given intravenous infusion in equal volume of Iso 8 microg/kg per min (dissolved in glucose 5%) and placebo (glucose 5%). A wash-out period of 25 min was observed between the infusions. Measurements included blood pressure (BP), heart rate (HR), PWV, and AI. PWV were determined using complior (Complior, Artech-Medical, Paris, France). AI and aortic PP were obtained from pulse wave analysis of radial applanation tonometry, using transfer function (SphygmoCor Windows software). RESULTS: Baseline AI increased (P < 0.05) with aging, a lower height and a larger diastolic BP (DBP). Iso increased (P < 0.0001) HR, brachial SBP, brachial and aortic PP as compared with placebo. In contrast, Iso decreased (P < 0.05) AI, brachial DBP, peripheral PWV, but not aortic PWV. Decrease of AI induced by Iso was not related to PWV. In stepwise multiple regression changes in HR, brachial SBP and DBP were independent determinants of AI response to Iso (r = 0.78, P < 0.0001). CONCLUSIONS: Our findings show that AI and PP fail as surrogate measures of arterial stiffness during beta-adrenergic stimulation.  相似文献   

12.
BACKGROUND: Aortic pressure waveforms are calculated non-invasively by applying generalized transfer functions (GTF) to tonometric radial pressure waveforms. Input errors mainly during acquisition and calibration of tonometric pressures are "transferred" to aortic pressure calculation. The present study aimed to quantify the proportion of specific input errors which is "transferred" by the GTFs in a wide range of hemodynamic conditions and for different error combinations in brachial systolic (SBP) and diastolic (DBP) blood pressure measurements. METHODS: Aortic pulse wave analysis was performed in 103 subjects (52 normotensive and 51 untreated hypertensive) by the SphygmoCor System. Each pressure waveform was initially calibrated by sphygmomanometrical brachial pressures. Isolated, parallel and reverse errors in brachial SBP/DBP from -10 to +10 mmHg were simulated, by recalibration of the recorded radial pressure waveforms, inducing specific "errors" of GTF-input values. For every recalculated aortic SBP and DBP, the difference from the initial estimated value was considered to represent the "transferred error" to the aortic pressure estimation. RESULTS: Parallel errors by +/-5 mmHg in both SBP and DBP resulted to an identical change in GTF-derived aortic pressures, as expected. When an overestimation in SBP by 5 mmHg and an underestimation in DBP by -5 mmHg occurred (reverse errors), almost 56% of this error (approximately 2.8 mmHg) was transferred. An isolated error in brachial SBP by +/-5 mmHg was transmitted by 76% ( approximately 3.8 mmHg) to GTF-derived aortic SBP. In subjects with mean blood pressure>117 mmHg or with heart rates<74 bpm, a greater percent of the calibration error was transferred to GTF-derived blood pressures. CONCLUSIONS: Input errors in brachial pressure values result in a quantifiable effect on transfer function output (aortic pressures). The percent of the "error transfer" by the GTFs depends on heart rate and BP levels, which should be taken into account when applying GTFs at populations with different hemodynamic conditions.  相似文献   

13.
目的比较培哚普利和美托洛尔对轻中度高血压病患者中心动脉压与肱动脉压的影响。方法在冠状动脉造影结束后,分别同步测量145例高血压病或(和)冠心病患者升主动脉根部(直接测量法)和肱动脉(袖带加压法)的血压,其中单药降压治疗二周以上的轻中度高血压病患者分为培哚普利组(4mg/d,62例)、美托洛尔组(25mg/d,39例)。结果升主动脉收缩压高于袖带加压法测量的肱动脉收缩压9.6mmHg(P<0.01),升主动脉舒张压低于袖带加压法肱动脉舒张压2.0mmHg(P<0.01),升主动脉脉压较肱动脉脉压大11.6mmHg(P<0.01)。虽然培哚普利组和美托洛尔组袖带加压法测得的肱动脉压相同,但是培哚普利组的升主动脉收缩压低于美托洛尔组(P<0.05)。结论升主动脉压与袖带加压法测得的肱动脉压差异有非常显著意义。虽然培哚普利和美托洛尔降低肱动脉压效果相似,但培哚普利降低升主动脉收缩压较美托洛尔更显著。  相似文献   

14.
OBJECTIVES: We have earlier showed endothelium-dependent vasodilation (EDV) in forearm resistance arteries to be mainly related to diastolic blood pressure (DBP), whereas flow-mediated vasodilation (FMD) was mainly related to systolic blood pressure (SBP) when measured with a mercury sphygmomanometer in the brachial artery. Here, we investigated whether these relationships were more powerful if blood pressure was measured invasively or by transformation to central aortic blood pressure. METHODS: In the prospective study of the Vasculature in Uppsala Seniors, 1016 patients aged 70 years were evaluated by the invasive forearm technique with acetylcholine (EDV), and brachial artery ultrasound to assess FMD. Blood pressure was measured with a mercury sphygmomanometer, invasively in the brachial artery and transformed to aortic blood pressure by pulse wave analysis. RESULTS: EDV was related to DBP with a similar strength regardless of whether DBP was measured traditionally, invasively or as calculated aortic pressure. Similarly, FMD was related to SBP with similar strength regardless of whether SBP was measured traditionally, invasively or as calculated aortic pressure. Only FMD was significantly related to pulse pressure. CONCLUSION: Measurements of blood pressure invasively or by calculation of aortic blood pressure did not increase the power of the associations between blood pressure and EDV in the elderly, when compared with traditional blood pressure measurements.  相似文献   

15.
We compared dilevalol (an isomer of labetalol), 200-400 mg daily, against atenolol, 50-100 mg daily, in a double-blind, crossover, placebo-controlled trial with respect to effects on arterial distensibility (measured as pulse wave velocity [PWV]) and wave reflection (assessed from carotid pressure wave contour). Twelve patients of mean age 58 years (range 44-73 years) with essential hypertension (supine diastolic blood pressure 95-114 mm Hg) took active therapy for 12 weeks, separated by a 2-4 week placebo period. Carotid pressure waveforms were recorded noninvasively by applanation tonometry with a Millar micromanometer-tipped probe. PWV was measured between carotid and femoral arteries (aortic PWV), carotid and radial arteries (arm PWV), and femoral and pedal arteries (leg PWV). Early wave reflection was calculated from the ratio of the height of the peak of the carotid wave above its shoulder to the pulse pressure and was expressed as an augmentation index. Both drugs were equally effective in reducing brachial sphygmomanometric pressure and PWV in all three regions (active vs. placebo, p less than 0.001), but there was no significant difference between the two active therapies. However, the augmentation index (averaged during the treatment period) was significantly lower with dilevalol (19%) than with atenolol (28%, p less than 0.01), corresponding to a greater decrease of 5-8 mm Hg in carotid systolic pressure compared with the brachial artery. Although both drugs were equally effective in reducing arterial distensibility, the vasodilating action of dilevalol gave added benefit in reducing wave reflection, presumably through its vasodilatory effect on peripheral conduit arteries.  相似文献   

16.
It remains uncertain whether intensive antihypertensive therapy can normalize pulsatile hemodynamics resulting in minimized residual cardiovascular risks. In this study, office and 24‐hour ambulatory systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure, carotid‐femoral pulse wave velocity (PWV), and forward (Pf) and reflected (Pb) pressure wave from a decomposed carotid pressure wave were measured in hypertensive participants. Among them, 57 patients whose 24‐hour SBP and DBP were normalized by three or more classes of antihypertensive medications were included. Another 57 age‐ and sex‐matched normotensive participants were randomly selected from a community survey. The well‐treated hypertensive patients had similar 24‐hour SBP, lower DBP, and higher PP values. The treated patients had higher PWV (11.7±0.3 vs 8.3±0.2 m/s, P<.001), Pf, Pb, Pb/Pf, and left ventricular mass index values. After adjustment for age, sex, body mass index, and office SBP, the differences for PWV, Pb, and Pb/Pf remained significant. Hypertensive patients whose 24‐hour SBP and DBP are normalized may still have markedly increased arterial stiffness and wave reflection.  相似文献   

17.
目的 探讨厄贝沙坦联合维生素D对老年高血压患者晨峰血压及动脉僵硬度的影响.方法 选择我院2020年1月至6月期间收治的老年高血压病患者80例,随机分为对照组(40例)和观察组(40例).对照组口服厄贝沙坦片治疗,观察组在此基础上肌注维生素D3治疗.比较两组治疗前后24h平均收缩压(24h SBP)、平均舒张压(24h ...  相似文献   

18.
Aim: The mechanism underlying the stiffness of the aorta and iliofemoral artery that is required to maintain blood pressure (BP) is unclear. A new stiffness index of the aorta (aBeta) and iliac-femoral arteries (ifBeta) was defined by applying the cardio-ankle vascular index (CAVI). We compared changes in stiffness of the two arteries in response to reduced BP, due to the non-selective α adrenergic blocker phentolamine and the β 1 adrenergic blocker atenolol, in rabbits. Methods: Pressure waves at the origin (oA) and distal ends of the aorta (dA) and the distal end of the left femoral artery (fA) were recorded simultaneously using three pressure sensors in 25 anesthetized rabbits. Phentolamine (50 µg/kg/min) and atenolol (10 mg/kg/min) were infused for 2 min. The pulse wave velocity (PWV) in each artery was determined; aBeta, ifBeta, and whole Beta (aifBeta) were calculated by the following formula; Beta=2ρ/PP×ln(SBP/DBP)×PWV 2 (ρ: blood density; SBP, SBP, and PP: systolic, diastolic, and pulse pressures, respectively). Results: SBP and DBP at oA, dA, and fA decreased by the administration of phentolamine and atenolol, with and without decreased total peripheral vascular resistance. After phentramine infusion, cardiac output (CO), aBeta, and aifBeta increased, while ifBeta decreased. After infusion of atenolol, CO decreased, while aBeta, ifBeta, and aifBeta remained unchanged. Conclusion: The contradictory reactions of aBeta and ifBeta to phentolamine suggest that the stiffness of the aorta and ilio-femoral artery is regulated separately during decreased BP induced by phentolamine, but not by atenolol.  相似文献   

19.
OBJECTIVE: To assess the effects of incremental phenylephrine infusion rates and subsequent graded vasoconstriction upon the performance of the Ohmeda Finapres. DESIGN: Blood pressure in eight hypertensive patients in the finger and the brachial artery was recorded simultaneously. Systolic blood pressure (SBP), diastolic blood pressure (DPB) and mean arterial pressure (MAP) were compared as well as additional waveform characteristics like the pressure at moment of the dicrotic notch and calculation of the pulsatile-systolic areas. RESULTS: Before phenylephrine infusion SBP and DBP were higher in the finger. At maximal infusion (1.6 micrograms/kg/min) the increase in brachial SBP was significantly underestimated by Finapres. Thus, the computed sensitivities of baroreflex control for SBP differed significantly between the two measurements. Under control conditions, the shape of the finger waveform differed from the brachial-artery waveform in terms of: (1) a more peaked appearance; (2) a dicrotic notch (Pnotch) which is located at a lower percentage of pulse pressure; and (3) a larger pulsatile-systolic area. At maximal infusion rates finger Pnotch increased whilst intrabrachial Pnotch did not. In contrast, the brachial and finger pulsatile-systolic areas changed fully in parallel. CONCLUSIONS: Phenylephrine infusion caused a significant, and clinically important, underestimation of the increase in brachial SBP when assessed by Finapres, whereas MAP and DBP and pulsatile-systolic area track intra-arterial pressure reliably.  相似文献   

20.
Aortic pulse wave velocity (PWV) is a significant and independent predictor of cardiovascular disease in hypertensive subjects and in patients with end-stage renal disease, but there have been few studies on PWV in Chinese patients with essential hypertension. In this cross-sectional study, we investigated 3,156 consecutive patients (mean age: 53.7 +/- 11.58 years) of the Hypertension Division of Ruijin Hospital in Shanghai. Together with sphygmomanometric blood pressure measurements, aortic PWV was measured using a validated automatic device. PWV in patients with pulse pressure (PP) > or = 60 mmHg was significantly greater than that in patients with PP < 60 mmHg (p < 0.01). PP and PWV were positively related to age (PP: r = 0.396, p = 0.001; PWV: r = 0.531, p = 0.001). After adjustment by age and heart rate, PWV was still closely related to PP (r = 0.249, p = 0.001). At any given systolic blood pressure (SBP), PWV significantly decreased with the increase of diastolic blood pressure (DBP), whereas at any given DBP there was a significant increase of PWV with the increase of SBP. In conclusion, PWV was the major determinant of PP, and was highest in Chinese patients with isolated systolic hypertension, followed by those with systolic and diastolic hypertension, isolated diastolic hypertension, and normal blood pressure.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号