Variability in blood pressure and arterial hypertension

Blood pressure variability in hypertension is an independent risk factor of cardiovascular complications, especially of stroke. Antihypertensive drugs/classes with powerful antihypertensive effect and suppression of blood pressure variability might have additional impact on the cardiovascular risk in clinical practice. Current evidence suggests that calcium channel blockers (CCB) decrease blood pressure variability more than all other antihypertensive classes. Combination of CCB with ACE-inhibitors suppresses blood pressure variability more than diuretics plus beta-blockers. Within-visit blood pressure variability (measured as coefficient of standard deviation) seems to be relatively simple and strong predictor of stroke and cardiovascular events.     

Effectiveness of the treatment of arterial hypertension in a specialized service. An audit using the automatic measurement of arterial blood pressure

The ineluctable fade out of mercury sphingomanometer pressure device involve the necessity in using automatic blood pressure systems. In parallel the recent PHARE II study witness of a lack in the control of hypertension in general practice. In the basis of an automatic blood pressure device measure, we had try to know the efficiency of blood pressure contr?l (BPC) in a specialised consultation. METHOD: 100 patients with essential systolo-diastolic hypertension (HTA) were screened. An independent physician measured the blood pressure level with an OMRON 705 CP device 3 times. The acceptable BPC was considered less than 160/95 mmHg and the optimal BPC less than 140/90 mmHg. There was 70 man, 30 female (mean age = 67 year old). The initial mean blood pressure was 169/104 mmHg. RESULTS: The final blood pressure measured was 137/80 mmHg. The percentage of patients who have an acceptable contr?l (< 160/95) was 91% and an optimal contr?l (< 140/90) 66%. 12% of these 66 maintain a height cardio-vascular risk. The mean number of medication used was 2 and it's paradoxally not differ between the optimal blood pressure control group and the other patients who need probably an intensive medication. In conclusion these study shows us the importance in understanding our patients particularity in order to increase the treatment efficiency.     

Beyond blood pressure reduction in the treatment of arterial hypertension. Clinical implications of the LIFE study

To date, blood-pressure lowering has been the main therapeutic objective in patients with arterial hypertension, regardless of the drug used, except for drugs selected for accompanying conditions. The LIFE study, carried out in 9,193 high-risk hypertensive patients (with ECG criteria of left ventricular hypertrophy), has shown that a therapeutic regimen based on losartan combined with a thiazide was accompanied by a significant reduction in the risk of cardiovascular complications in more than 90% of patients compared with atenolol and a thiazide over a mean follow-up period of 4.8 years. The incidence of the primary endpoints (cardiovascular death, stroke, and myocardial infarction) was 11% in the losartan group and 13% in the atenolol group (13% relative risk reduction, p = 0.021). Losartan therapy was associated with more benefits in stroke risk reduction and in the development of new cases of diabetes. In the analysis of the subgroup of 1,195 patients with hypertension and diabetes included in the LIFE study, losartan had a special prognostic benefit. One of the cardiovascular events included as a primary endpoint was observed in 18% of the losartan-treated patients and in 23% of the atenolol-treated patients (24% relative risk reduction, p = 0.031).The LIFE trial showed that losartan produced better cardiovascular protection than atenolol, a similar blood pressure reduction, and was better tolerated. This drug seems to confer extra cardiovascular protection in addition to reducing blood pressure.     

Automated blood pressure measurement for diagnosing hypertension

Guidelines for the management of hypertension have started to include home blood pressure (BP) and 24-h ambulatory BP monitoring as preferred methods for diagnosing hypertension. The next step will be to incorporate automated office BP measurement into the algorithm for diagnosing hypertension. Recent studies support this approach with automated office BP readings being closely correlated with the ambulatory BP.     

Role of leptin in blood pressure regulation and arterial hypertension

Leptin is a 16-kDa protein secreted by white adipose tissue that is primarily involved in the regulation of food intake and energy expenditure. Plasma leptin concentration is proportional to the amount of adipose tissue and is markedly increased in obese individuals. Recent studies suggest that leptin is involved in cardiovascular complications of obesity, including arterial hypertension. Acutely administered leptin has no effect on blood pressure, probably because it concomitantly stimulates the sympathetic nervous system and counteracting depressor mechanisms such as natriuresis and nitric oxide (NO)-dependent vasorelaxation. By contrast, chronic hyperleptinemia increases blood pressure because these acute depressor effects are impaired and/or additional sympathetic nervous system-independent pressor effects appear, such as oxidative stress, NO deficiency, enhanced renal Na reabsorption and overproduction of endothelin. Although the cause-effect relationship between leptin and high blood pressure in humans has not been demonstrated directly, many clinical studies have shown elevated plasma leptin in patients with essential hypertension and a significant positive correlation between leptin and blood pressure independent of body adiposity both in normotensive and in hypertensive individuals. In addition, leptin may contribute to end-organ damage in hypertensive individuals such as left ventricular hypertrophy, retinopathy and nephropathy, independent of regulating blood pressure. Here, current knowledge about the role of leptin in the regulation of blood pressure and in the pathogenesis of arterial hypertension is presented.     

Effect of bisoprolol on blood pressure and arterial hemodynamics in systemic hypertension.

Blood pressure, heart rate, common carotid and brachial arterial hemodynamics using pulsed Doppler flowmetry and pulse wave velocity determinations were evaluated using a double-blind crossover design versus placebo in 14 patients with sustained essential hypertension treated by the selective beta 1 blocking agent bisoprolol. Blood pressure and heart rate significantly decreased after bisoprolol, whereas no significant change occurred in the diameter, the blood flow and in the vascular resistance of the carotid and brachial circulations. Pulse wave velocity significantly decreased in the brachioradial and the carotid femoral areas. The decrease in the latter was -1.6 +/- 0.8 m/s with bisoprolol and -0.06 +/- 0.80 m/s with placebo (p = 0.001). Brachial artery compliance significantly increased from 117 +/- 49 to 205 +/- 84 cm4 x dynes-1 x 10(9) (p = 0.001), indicating that the antihypertensive effect of beta 1 blockade is associated with an improvement in the viscoelastic properties of the brachial artery wall.     

血压、脉压水平及高血压病程对高血压患者动脉僵硬度的影响

目的探讨血压、脉压水平及高血压病程对高血压患者动脉僵硬度的影响。方法从上海市宝山区6家社区卫生中心及本院入选1026例高血压患者,收集相关病史信息,检测其颈-股动脉(C-F)、颈-桡动脉(C-R)、颈-足背动脉(C-D)脉搏波传导速度(PWV),672例患者在随访1年后复测PWV。从血压、脉压、高血压病程3者的不同水平进行分组比较及随访前后对照分析。结果 (1)1、2、3级高血压患者的C-FPWV随血压水平的增高而增快,分别为(12.61±2.76)m/s,(14.35±3.41)m/s,(15.50±2.93)m/s(均为P<0.01)。1级高血压组较2级、3级高血压组C-FPWV差异有统计学意义(均为P<0.01)。(2)随访前后C-FPWV在1级和2级高血压组分别为(12.73±2.91)m/s和(13.39±3.25)m/s,(13.96±3.07)m/s和(14.75±4.10)m/s,差异有统计学意义,而在3级高血压组差异无统计学意义。(3)脉压<40 mm Hg,40～60 mm Hg,≥60 mm Hg 3组C-FPWV随脉压的增大而增快,分别为(11.95±2.60)m/s,(12.94±2.85)m/s,(14.89±3.22)m/s(均为P<0.01)。随访1年后3组的C-FPWV分别较前增快0.70 m/s,0.65 m/s,0.85 m/s,差异均有统计学意义。(4)高血压病程<5年、5～10年、≥10年3组C-FPWV分别为(12.77±2.75)m/s,(12.85±3.07)m/s,(13.76±3.05)m/s,3组比较差异有统计学意义(均为P<0.01),病程越长,C-FPWV越快。结论(1)C-FPWV较C-RPWV、C-DPWV更能反映动脉僵硬度的变化。(2)C-FPWV随血压、脉压水平的增高及高血压病程的延长而增快,3者均为动脉僵硬度的重要影响因素。     

Long-term automatic blood pressure measurement in clinical management

Blood pressure control in arterial hypertension, as has been shown in randomized studies in 43,000 patients, based on a reduction of diastolic blood pressure of 5.8 mm Hg associated with a 40% reduction in stroke, is of substantial prognostic importance. Cardiac events were reduced insignificantly by 9%. Major problems with treatment are the limited acceptance of a lifelong therapy--in the Munich High Blood Pressure Study from 1982 well controlled and effective treatment was found in only 22% of the men and 16% of the women--uncertainty with regard to the indication and the question of whether the observed blood pressure elevation is situational or persistent in particular, in view of one study reporting that after three years of placebo in 48% of patients entered with diastolic values between 95 and 105 mm Hg, the blood pressure was found to lie in the normal range. Blood pressure determinations by the patients themselves may reflect resting values throughout the day but blood pressure fluctuations which can be substantial, can only be detected by ambulatory monitoring. The aim of this study, in addition to assessment of the reliability of the system employed, was to compare the response of the monitored blood pressure in patients with various stages of hypertension and in normal subjects at rest and during physical exertion to identify more accurately those in need of antihypertensive treatment. For ambulatory blood pressure monitoring, the SpaceLabs Model ICR 5200 was used. If Korotkoff sounds are not detected, the unit switches to oscillatory measuring. The storage capacity accommodates 200 measurements of systolic, diastolic and mean arterial pressure, heart rate and time of measurement.(ABSTRACT TRUNCATED AT 250 WORDS)     

解读2005年《中国高血压防治指南(修订版)》(四)(续)高血压治疗中收缩压与脉压的意义

3收缩压及脉压增高对靶器官的损害3.1左心室肥厚高血压引起的左心室肥厚(left ven-tricular hypertrophy,LVH)是左室壁为平衡动脉血压的升高而发生的适应性改变过程,多种血液动力学和非血液动力学因素参与了LVH的形成。前者主要是压力负荷和容量负荷,后者包括遗传因素、交感神经张力、肾素-血管紧张素系统的活性、肥胖以及血液黏稠度等。无论对于总死亡率,还是对于心血管事件的发病率和死亡率,经超声心动图诊断的LVH都是一个很强的、独立的危险因素。Benetos等对12721例血压正常者和7324例高血压患者随访19.2年发现,脉压水平升高是心血…     

The measurement of blood pressure and the detection of hypertension in children and adolescents.

Despite the publication of several expert committee guidelines for the measurement of blood pressure (BP) and the diagnosis of hypertension in children and adolescents, it was our perception and clinical experience that there still appeared to be a general lack of standardisation of BP measurement techniques and little consensus on the criteria for diagnosing hypertension. To investigate this further, we have conducted a postal survey of consultant-grade paediatricians who were members of the British Paediatric Association (BPA). A total of 1500 questionnaires were sent out and 708 analysable replies were received (47.1%). This showed that 68.6% of paediatricians routinely measured BP, at least on one occasion, in children or adolescents attending their outpatient clinics, 17.7% started at or soon after birth, 12.3% started at the age of 1 year, 20.0% at 3 years, 12.0% from 7 years of age and 3.5% from the age of 13. Only 60.5% reported that they had a choice of four or more different cuff sizes in their clinic. Forty-one percent of respondents reported that the BP was always or sometimes measured by nurses. Fifty-one percent of respondents measured diastolic BP at the phase of muffling of sound (Korotkoff phase IV), 31.9% used the disappearance of sound (phase V) whilst 15.9% claimed that they measured both end-points. The criteria for diagnosing a child as being hypertensive varied greatly; 17.9% reported that they responded to the systolic BP alone, 13.5% to the diastolic BP alone, 65.9% relied on both pressures, and 2.7% responded to either the systolic or diastolic pressure if it was raised. Furthermore, 12.9% diagnosed hypertension if the BP exceeded the 90th percentile in relation to age and 41.8% used the 95th percentile. However 45.3% of respondents employed a higher dividing line. In hospitalised children, leg blood pressures were measured routinely by 30.3%, although a further 44.0% would do so if aortic coarctation or other vascular diseases were suspected. Despite considerable variation in clinical practice, techniques and criteria, only 11.4% of clinicians would manage the patients themselves, with the remainder referring the child on to the appropriate specialist. The survey suggests a general lack of standardisation of BP measurement techniques and little consensus on the criteria for diagnosing hypertension amongst paediatricians. Simplified, shortened and updated guidelines on hypertension in paediatric practice and research are needed.     

Accuracy of telemedical home blood pressure measurement in the diagnosis of hypertension

This study was conducted to compare the accuracy of clinic blood pressure (CBP) and telemedical home blood pressure (HBP) measurement in the diagnosis of hypertension in primary care. The study subjects were 411 patients with average CBP > or =140 mmHg systolic or > or =90 mmHg diastolic, who performed telemedical HBP measurement (5 days, four times daily) and ambulatory blood pressure (ABP) monitoring in random order. Main outcome measure was the agreement of CBP and HBP with daytime ABP. CBP was much higher than daytime ABP and average HBP (P<0.001) with no difference between the latter two. The correlation between CBP and ABP was weak (systolic: r=0.499, diastolic: r=0.543), whereas strong correlations existed between HBP and ABP (systolic: r=0.847, diastolic: r=0.812). A progressive improvement in the strength of the linear regression between average HBP of single days and ABP was obtained from day 1 to day 4, with no further benefit obtained on the fifth day. The HBP readings taken at noon and in the afternoon showed significantly stronger correlations with ABP than the blood pressures measured in the morning and in the evening. In conclusion, the accuracy of telemedical HBP measurement was substantially better than that of CBP in the diagnosis of hypertension in primary care. HBP most accurately reflected ABP on the fourth day of monitoring, and the readings at noon and in the afternoon seemed to be most accurate.