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Item does not contain fulltext OBJECTIVE: To determine the separate contribution of the physician and the hospital environment to differences between home (HBP) and office BP (OBP). METHODS: For 3 consecutive days, 65 hypertensive patients measured their HBP. OBP was determined with the same device by the physician. A higher OBP than HBP was regarded as white-coat effect (WCE), whereas lower OBP than HBP was regarded masked effect. OBP was measured automatically before, during and after the presence of the physician. The physician effect was the BP rise caused by the entrance of physician. The WCE minus the physician effect was regarded the hospital's contribution to the BP differences (hospital effect). We assessed the magnitudes of the hospital effect and the physician effect in determining the WCE. Furthermore, we assessed the correlation of these BP phenomena with each other, and with clinical variables. RESULTS: The WCE consisted of 4.6/-1.7 +/- 9.9/10.9 mmHg hospital effect and of 4.4/3.4 +/- 6.6/3.3 mmHg PE. The masked effect consisted of a substantially larger hospital effect (19.6/9.4 +/- 12.7/9.5 mmHg) than physician effect (4.6/3.0 +/- 6.4/3.9 mmHg). Physician effect did not correlate with systolic or diastolic WCE or masked effect (r = -0.05 to 0.08, P > 0.39). In regression analysis, age, baseline mean arterial pressure and BMI were not significantly associated with WCE (all P values >0.4). CONCLUSION: BP differences between home and office can largely be attributed to the hospital environment rather than to the entrance of the physician. The physician-related BP effect is not related to differences of HBP and OBP.

Background: Blood pressure (BP) is one of the major vital parameters monitored in the stroke unit. The accuracy of indirect BP measurement is strongly influenced by the position of both patient and arm during the measurement. Acute stroke patients are often nursed in lateral decubitus positions. The effect of these alternating body positions in relation to affected body side on the outcome and reliability of BP readings in acute stroke patients is unknown. Methods: An automatic oscillometric BP device was used. BP was measured in both arms in the (back) supine and both lateral decubitus positions. Results: In total, 54 consecutive acute stroke patients were included. Thirty-five patients had right-sided deficits and 19 patients had left-sided deficits. Supine BP readings were similar in the right and left arms regardless of side of deficit. Measurements of BP in the lateral decubitus positions resulted in significantly lower BP readings in the uppermost arm (around 12 mm Hg in both arms) and significantly higher readings in the right lowermost arm (around 6 mm Hg) compared to the supine position. This effect seemed less pronounced when the left lowermost arm was measured. There was no relation between change of BP readings in various lateral positions and side of stroke. Conclusions: Alternating lateral decubitus positions according to nursing standards in acute stroke patients lead to a mean 18 mm Hg BP fluctuation. This may largely be explained by hydrostatic pressure effects, partly by anatomic factors in the left lowermost arm, but not by the side of stroke.

Background and Purpose— The effects of early upright positioning in the acute phase of ischemic stroke on both blood pressure and functional outcome have not been previously examined. Methods— Prospective investigation of mean arterial pressure, heart rate, and peripheral oxygen saturation in the supine, sitting, and (if achievable) active standing position 1, 2, and 3 days after an acute stroke was performed. Also investigated was the presence of a significant postural blood pressure rise and fall using orthostatic definitions and the relation to functional outcome after 3 months. Results— One hundred sixty-seven patients were included (mean age, 68.5±15.2 years; median National Institutes of Health Stroke Scale, 7). Approximately 60% of the patients were able to stand. On average the mean arterial pressure increased when patients moved from the supine to sitting (Day 1: Δ 3.9 mm Hg; P P P =0.003). Moving to the standing position was accompanied by an increase of heart rate. No difference in oxygen saturation was observed in the various positions over the period of investigation. Conclusions— We found that a significant blood pressure rise during early upright positioning in patients with acute stroke was independently associated with a favorable outcome. No contraindication to early mobilization was found in this study.

Background Screening for inter-arm difference (IAD) of blood pressure (BP) at each first visit is recommended by numerous guidelines whereas it is unclear whether the method by which IAD is measured has significant influence on the IAD value. Methods A systematic review is made of the studies reporting on double-arm measurements and the association of IAD with procedure characteristics (Medline/PubMed, Embase, and Cochrane Library). Results The mean absolute IAD was 5.4 +/- 1.7 and 3.6 +/- 1.2 mm Hg for systolic and diastolic BP, respectively. Of all subjects 14% had a systolic IAD >= 10 mm Hg, 4% a systolic IAD >= 20 mm Hg, and 7% a diastolic IAD >= 10 mm Hg. The relative risk (RR) of obtaining a systolic IAD >= 10 and 20 mm Hg and a diastolic IAD >= 10 mm Hg is higher when measuring sequentially instead of simultaneously (2.2 (95% CI: 1.4-3.6), P

Background Although blood pressure measurement is one of the most frequently performed measurements in clinical practice, there are concerns about its reliability. Serial, automated oscillometric blood pressure measurement has the potential to reduce measurement bias and white-coat effect9 Aim To study agreement of 30-minute office blood pressure measurement (OBPM) with standardised OBPM, and to compare repeatability Design and setting Method comparison study in two general practices in the Netherlands Method Thirty-minute and standardised OBPM was carried out with the same, validated device in 83 adult patients, and the procedure was repeated after 2 weeks. During 30-minute OBPM, blood pressure was measured automatically every 3 minutes, with the patient in a sitting position, alone in a quiet room. Agreement between 30-minute and standardised OBPM was assessed by Bland–Altman analysis. Repeatability of the blood pressure measurement methods after 2 weeks was expressed as the mean difference in combination with the standard deviation of difference (SDD) Results Mean 30-minute OBPM readings were 7.6/2.5 mmHg (95% confidence interval [CI] = 6.1 to 9.1/1.5 to 3.4 mmHg) lower than standardised OBPM readings. The mean difference and SDD between repeated 30-minute OBPMs (mean difference = 3/1 mmHg, 95% CI = 1 to 5/0 to 2 mmHg; SDD 9.5/5.3 mmHg) were lower than those of standardised OBPMs (mean difference = 6/2 mmHg, 95% CI = 4 to 8/1 to 4 mmHg; SDD 10.9/6.3 mmHg). Conclusion Thirty-minute OBPM resulted in lower readings than standardised OBPM and had a better repeatability. These results suggest that 30-minute OBPM better reflects the patient9s true blood pressure than standardised OBPM does.

There is an increasing interest for using telecare(TC) in the management of hypertension. A systematic review to the use of blood pressure (BP) measurement in TC has been performed (Medline/PubMed, Embase, and Cochrane Library), selecting randomized clinical trials that compared TC with usual care (UC) for hypertension management (treatment and/or coaching). Nine randomized clinical trials were selected (n=2501, 61.4±0.6 years, 42±2.7% males). Overall there was a significant larger decrease in the TC group than in the UC group for systolic (5.2±1.5 mmHg; P

Contains fulltext : 97584.pdf (Publisher’s version ) (Open Access) PURPOSE: Current office blood pressure measurement (OBPM) is often not executed according to guidelines and cannot prevent the white-coat effect. Serial, automated, oscillometric OBPM has the potential to overcome both these problems. We therefore developed a 30-minute OBPM method that we compared with daytime ambulatory blood pressure. METHODS: Patients referred to a primary care diagnostic center for 24-hour ambulatory blood pressure monitoring (ABPM) had their blood pressure measured using the same validated ABPM device for both ABPM and 30-minute OBPMs. During 30-minute OBPM, blood pressure was measured automatically every 5 minutes with the patient sitting alone in a quiet room. The mean 30-minute OBPM (based on t = 5 to t = 30 minutes) was compared with mean daytime ABPM using paired t tests and the approach described by Bland and Altman on method comparison. RESULTS: We analyzed data from 84 patients (mean age 57 years; 61% female). Systolic and diastolic blood pressures differed from 0 to 2 mm Hg (95% confidence interval, -2 to 2 mm Hg and from 0 to 3 mm Hg) between mean 30-minute OBPM and daytime ABPM, respectively. The limits of agreement were between -19 and 19 mm Hg for systolic and -10 and 13 mm Hg for diastolic blood pressures. Both 30-minute OBPM and daytime ABPM classified normotension, white-coat hypertension, masked hypertension, and sustained hypertension equally. CONCLUSIONS: The 30-minute OBPM appears to agree well with daytime ABPM and has the potential to detect white-coat and masked hypertension. This finding makes 30-minute OBPM a promising new method to determine blood pressure during diagnosis and follow-up of patients with elevated blood pressures.

OBJECTIVE: The goal of this review study is to summarize 30 years of research on cut-off limits for the self-measured blood pressure. METHODS: We reviewed two meta-analyses, several prospective outcome studies in populations and hypertensive patients, studies in pregnant women, three clinical trials and the thresholds proposed in earlier and current hypertension guidelines. RESULTS: In line with existing guidelines, prospective studies support that levels of the self-measured blood pressure at home of greater than or equal to 135 mmHg systolic or greater than or equal to 85 mmHg diastolic indicate hypertension. Circumstantial data suggest that levels of the self-measured blood pressure below 120/80 and 130/85 mmHg are optimal and normal, respectively. Therapeutic targets of the self-measured blood pressure to be attained on antihypertensive drug treatment are currently unknown, but should logically be lower (

The ambulatory arterial stiffness index (AASI) is derived from 24-hour ambulatory blood pressure recordings. We investigated whether the goodness-of-fit of the AASI regression line in individual subjects ( r 2 ) impacts on the association of AASI with established determinants of the relation between diastolic and systolic blood pressures. We constructed the International Database on the Ambulatory Blood Pressure in Relation to Cardiovascular Outcomes (7604 participants from 6 countries). AASI was unity minus the regression slope of diastolic on systolic blood pressure in individual 24-hour ambulatory recordings. AASI correlated positively with age and 24-hour mean arterial pressure and negatively with body height and 24-hour heart rate. The single correlation coefficients and the mutually adjusted partial regression coefficients of AASI with age, height, 24-hour mean pressure, and 24-hour heart rate increased from the lowest to the highest quartile of r 2 . These findings were consistent in dippers and nondippers (night:day ratio of systolic pressure ≥0.90), women and men, and in Europeans, Asians, and South Americans. The cumulative z score for the association of AASI with these determinants of the relation between diastolic and systolic blood pressures increased curvilinearly with r 2 , with most of the improvement in the association occurring above the 20th percentile of r 2 (0.36). In conclusion, a better fit of the AASI regression line enhances the statistical power of analyses involving AASI as marker of arterial stiffness. An r 2 value of 0.36 might be a threshold in sensitivity analyses to improve the stratification of cardiovascular risk.

It is still uncertain whether one can safely base treatment decisions on self-measurement of blood pressure. In the present study, we investigated whether antihypertensive treatment based on self-measurement of blood pressure leads to the use of less medication without the loss of blood pressure control. We randomly assigned 430 hypertensive patients to receive treatment either on the basis of self-measured pressures (n=216) or office pressures (OPs; n=214). During 1-year follow-up, blood pressure was measured by office measurement (10 visits), ambulatory monitoring (start and end), and self-measurement (8 times, self-pressure group only). In addition, drug use, associated costs, and degree of target organ damage (echocardiography and microalbuminuria) were assessed. The self-pressure group used less medication than the OP group (1.47 versus 2.48 drug steps; P P P =0.25/0.20), in changes in left ventricular mass index (−6.5 g/m 2 versus −5.6 g/m 2 ; P =0.72), or in median urinary microalbumin concentration (−1.7 versus −1.5 mg per 24 hours; P =0.87). Nevertheless, 24-hour ambulatory blood pressure values at the end of the trial were higher in the self-pressure than in the OP group: 125.9 versus 123.8 mm Hg ( P P

Item does not contain fulltext OBJECTIVE: To establish whether the results of blood pressure (BP) measurements are affected by wearing clothing underneath the BP cuff during measurement. METHODS: Normotensive and hypertensive patients (n=133; 65 men) of an outpatient clinic participated in this study. BP was measured according to a rigorous protocol with a validated oscillometric device under three conditions: with one layer of own clothing (OC) underneath the cuff, with one layer of standardized clothing (SC) underneath the cuff, and with the cuff on a bare arm (BA), in a randomized order. Patients were seated on a chair with their right arm on the table and their feet flat on the floor during BP measurement. RESULTS: The mean BP values (+/-SEM) measured during BA, OC, and SC were, respectively, 132.8+/-1.3, 132.3+/-1.4, and 133.2+/-1.4 mmHg for systolic blood pressure (SBP), 78.3+/-0.9, 78.3+/-0.9, and 78.5+/-0.9 mmHg for diastolic blood pressure (DBP), and 90.3+/-1.0, 90.0+/-1.0, and 91.5+/-1.0 mmHg for mean arterial blood pressure (MAP). The differences in SBP, DBP, and MAP between BA, OC, and SC measurements were not statistically significant, but there was considerable intraindividual variation in SBP deviations of more than 5 mmHg between BA versus OC and SC. There was no significant order effect of the three conditions. The absence of differences between BA, OC, and SC was not determined by age, sex, BMI, and arm circumference. CONCLUSION: We could not find differences in MAP, SBP, and DBP between the bare and clothed arms, but intraindividual variation of SBP between the three conditions is not negligible. Despite this caveat, these data suggest that in an outpatient clinic, BP can be measured reliably with one layer of clothing underneath the cuff. This is timesaving and more comfortable for patients.

Contains fulltext : 51044.pdf (Publisher’s version ) (Closed access) OBJECTIVE: Determining the influence of the position of the arm on blood pressure measurement in the sitting position. METHODS: Blood pressure of 128 individuals (the majority being treated hypertensive patients) visiting the outpatient clinic was measured simultaneously on both arms with arms in two different positions. First, both arms were placed at the chair support level and blood pressure was measured three times on both arms after 10 min of rest. Subsequently, while still remaining in the same sitting position, five blood pressure measurements were made simultaneously at both arms with one arm placed on the desk and one arm placed and supported at heart level (mid-sternal). The arm placed at heart level served as the reference arm. The choice of which arm was placed at desk level and which arm was placed at heart level was randomized. RESULTS: Both at desk level and at chair support level, mean (+/-SD) systolic and diastolic blood pressures were higher than blood pressure at heart level by 6.1/5.7+/-4.6/3.1 and 9.3/9.4+/-5.4/3.4 mmHg, respectively. The effect of the height differences between the arm positions on the blood pressure readings was smaller than predicted (0.49 mmHg/cm systolic and 0.47 mmHg/cm diastolic). No significant correlation was found between blood pressure difference in the different arm positions (desk and heart level) and age, sex, weight or baseline blood pressure. CONCLUSIONS: Different arm positions below heart level have significant effects on blood pressure readings. The leading guidelines about arm position during blood pressure measurement are not in accordance with the arm position used in the Framingham study, the most frequently used study for risk estimations.

BACKGROUND In validation studies reporting on the accuracy of blood pressure measuring devices (ambulatory and non-ambulatory systems), it is frequently stated that the accuracy of blood pressure devices seems to decrease at increasing blood pressure levels. This has been shown for several ambulatory devices in the past. Whether more recently validated devices are less accurate at increasing blood pressure levels is unknown, however. OBJECTIVES We therefore retrospectively searched the literature for studies performed between 1993 and 2003, reporting on the accuracy of blood pressure measuring devices over different blood pressure levels. When needed, additional information from the authors was requested. METHODS In total, 30 studies were selected. Of these, the studies reporting on the accuracy of 14 different ambulatory and nine different non-ambulatory devices were useful. For both ambulatory and non-ambulatory devices, accuracy appeared to decrease at increasing blood pressure levels. This was particularly shown for systolic blood pressure. RESULTS We speculate whether this finding is due to the oscillometric method of blood pressure measurement. Another explanation may exist, however. Blood pressure variability increases with higher blood pressure. Further, the British Hypertension Society protocol 1993 uses sequential measurements. This may be the reason that, owing to the increased blood pressure variability, the accuracy of most devices tends to decrease at higher blood pressure levels. Consequently, the accuracy of blood pressure measuring devices may be underestimated at higher blood pressure levels. CONCLUSION Currently used automated blood pressure measurement devices seem to be less accurate at increasing blood pressure levels. It is important to be aware of this phenomenon when treating hypertensive patients. The reported decrease in accuracy, however, may well be explained by the increasing blood pressure variability at increasing blood pressure and the use of sequential measurements. If this is the case, then the accuracy of these devices is perhaps underestimated.

Contains fulltext : 48523.pdf (Publisher’s version ) (Closed access) The ability to predict severity of the post-thrombotic syndrome (PTS) early after acute deep-vein thrombosis (DVT) is limited. The aim of our study was to examine the incidence of PTS prospectively and to evaluate the predictive value of non-invasive venous examinations shortly after DVT for the development of PTS. In 93 patients with DVT thrombosis score (TS), reflux, venous outflow resistance (VOR) and calf muscle pump dysfunction (CMP) were examined prospectively. After one, two and six years patients were evaluated for PTS using the clinical scale of the CEAP-classification (PTS present > or = 3 on a scale from 0 to 6). Area under the curves (AUC) were used to evaluate the predictive value of the non-invasive examinations at one and three months after diagnosis of DVT for future PTS. The cumulative incidence of PTS increased from 49% (32/65) after one year to 55% (36/65) and 56% (27/48) after two and six years, whereas the incidence of patients with PTS class 4 progressed from 20% after two years to 33% after six years. The prognostic value to predict PTS was highest for the combination of TS, VOR and reflux measured three months after diagnosis and showed an AUC of 0.77 (0.65-0.90) for PTS after one year. In conclusion, the incidence of PTS after DVT did not increase significantly after one year, whereas during longer follow-up the severity of PTS rose in patients with PTS. Moreover, measurement of TS, VOR and reflux three months after DVT could predict, with reasonable accuracy, the risk of PTS after one year of follow-up.

Progressive atherosclerosis followed by plaque rupture is the leading cause of acute cardiovascular events. Inhibition of platelet aggregation by acetylsalicylic acid (aspirin) reduces recurrent cardiovascular events in secondary prevention trials. By extracting data from available randomized trials that examined aspirin prevention in persons without previously known cardiovascular disease, we evaluated the use of aspirin as a primary prevention measure. Using the raw data presented in the source publication on death, fatal and nonfatal myocardial infarctions, and cerebrovascular accidents, all relative and absolute risk reductions were recalculated with confidence intervals. In healthy men above 45 years of age, men with an increased cardiovascular risk profile, and persons with diabetes mellitus or hypertension, the use of aspirin reduces the incidence of myocardial infarction and has a neutral effect on cerebrovascular events. The protective effect of aspirin is apparently most prominent in those persons with an increased risk of manifest atherosclerotic vascular disease. Notwithstanding these results, for each patient it remains essential to balance the cardiovascular risk profile against the small increased risk of bleeding complications when prescribing aspirin.

Item does not contain fulltext OBJECTIVE: To assess the effect of crossing legs at the knee level on wave reflection, as measured by the augmentation index. METHODS: Forty-two participants crossed their legs at the knee level (popliteal fossa over the suprapatellar bursa) in the sitting position for 12 min. One trained investigator performed the measurements before, during, and after leg crossing. We used the SphygmoCor to measure the augmentation index at the radial artery and an oscillometric device to measure blood pressure (BP) at the upper arm. We calculated the differences between the uncrossed and the crossed position for the augmentation index normalized for heart rate, peripheral BP, and central BP. RESULTS: Both peripheral systolic BP 2.5 +/- 6.5 (mean +/- SD) mmHg (0.5-4.6) (95% confidence interval) and peripheral diastolic BP 1.7 +/- 3.8 mmHg (0.5-2.9) increased during leg crossing compared with the uncrossed position. In addition, central systolic BP 2.8 +/- 5.8 (0.9-4.6) and central diastolic BP 1.8 +/- 3.9 (0.5-3.0) increased, whereas no significant change in the augmentation index was observed. CONCLUSION: Our results indicate that the increase in BP during leg crossing cannot be explained by wave reflection. We found no change in the augmentation index during leg crossing at the knee level. Central BP and peripheral BP are equally influenced by leg crossing.

1. The selective carbonic anhydrase inhibitor acetazolamide is known to increase blood flow in several organs. Acetazolamide directly dilates isolated resistance arteries associated with activation of calcium-activated potassium (K(Ca)) channels. We examined both the presence and mechanism of the direct vascular action of acetazolamide in vivo in humans. 2. Forearm vasodilator responses of 30 healthy volunteers to infusion of placebo and increasing doses of acetazolamide (1-3-10 mg min(-1) dl(-1)) into the brachial artery were recorded by venous occlusion plethysmography, before and after local administration of L-NMMA (0.2 mg min(-1) dl(-1), an inhibitor of NO-synthase, n=6), indomethacin (5.0 microg min(-1) dl(-1), an inhibitor of prostaglandin synthesis, n=6), glibenclamide (10 microg min(-1) dl(-1), an inhibitor of K(ATP) channels, n=6), tetraethylammonium (0.1 mg min(-1) dl(-1), an inhibitor of K(Ca) channels, n=6) or placebo (NaCl 0.9%, n=6). Lower dosages of acetazolamide did not affect vascular tone (n=6). 3. Acetazolamide infusions increased forearm blood flow from 2.41+/-0.17 to 2.99+/-0.18, 4.09+/-0.26 and 6.77+/-0.49 ml min(-1) dl(-1) in the infused forearm (P

The objective of this study was to determine the factors that influence diastolic blood pressure (DBP) and the incidence of hypertension. In 1977, DBP and cardiovascular risk factors were measured in 7092 men and women. In 1995, 2335 subjects participated at a second screening. Those patients already under hypertension treatment in 1977 were excluded. The DBP tracking was studied in subjects not under hypertension treatment during the study. Hypertension was defined on two ways in the analysis: under current hypertension treatment or a DBP > 95 mmHg measured at rescreening in 1995. Forty-seven percent of the subjects with a DBP 95 mmHg), 64% were still in that category in 1995. Baseline DBP in 1977 had the highest predictive value for future DBP. Weight gain over the years increased the risk for future hypertension: in contrast, there was no risk at a low DBP without weight gain. There is no need for regular check-ups for those patients with a low DBP who experience no weight gain. Borderline DBP (85-95 mmHg), together with weight gain, increases the risk of development of hypertension. The risk was especially high for men in the lower socioeconomic class.

Despite the many studies on venous haemodynamics using duplex, only a few evaluated the normal values, variability and reproducibility. Therefore, the range and variability of venous diameter, compressibility, flow and reflux were measured. To obtain normal values, 42 healthy individuals (42 limbs, 714 vein segments) with no history of venous disease were scanned by duplex. To determine the reproducibility the intra-observer variability was measured in 11 healthy individuals (187 vein segments) and the inter-observer variability in 15 healthy individuals (255 vein segments) and 13 patients (169 vein segments) previously diagnosed with deep venous thrombosis. Of the 714 normal vein segments, 708 (99%) were traceable, including the crural veins. Of the traceable vein segments, 675 (95%) were compressible and in 696 (98%) flow was present. Of the 42 common femoral vein segments, in 25 (60%) the reflux duration exceeded 1.0 s, but in the other proximal vein segments the reflux duration was less than 1.0 s (95% confidence interval 3.0–10.0). With the exception of the distal long saphenous vein, in the distal vein segments the reflux duration was less than 0.5 s (95% confidence interval 3.5–8.2). The coefficient of variation of the diameter measurements ranged from 14 to 50% and that of the reflux measurements from 28 to 60%. The κ-coefficient of the inter-observer variability in the classification of compressibility measurements in the patients was 0.77 and that of the reflux measurements was 0.86. This study shows that almost all veins were compressible in healthy individuals, except the distal femoral veins. In healthy individuals the duration of reflux of the proximal veins was less than 1.0 s and in the distal veins it was less than 0.5 s. The inter-observer variability of the reflux and compressibility measurements in the patients was good.

In this prospective study we examined the value of magnetic resonance angiography (MRA) in the imaging of the proximal renal arteries, with the main aim of detecting renal arterial stenosis, as compared with intraarterial digital subtraction angiography. The study was done among a group of 38 hypertensive patients seen in the outpatient department of the department of medicine of our university hospital. In all patients a magnetic resonance angiography and an intraarterial subtraction angiography of the renal arteries was made, and the outcomes of the investigations were compared. Clinical and biochemical data of the patients also were analyzed in relation to the presence or absence of a stenosis. In one patient, MRA resulted in technical failure because of unsuspected claustrophobia. Of the remaining 37 patients, 14 had renal artery stenosis. Of 12 patients in whom the stenoses were >50% of luminal surface on intraarterial digital subtraction angiography, eight were unilateral and four bilateral. All these stenoses were recognized by magnetic resonance angiography. There was also one false positive result by magnetic resonance. Thus, for the identification of stenoses >50%, magnetic resonance has a sensitivity of 100% and a specificity of 96%. Of the 12 accessory renal arteries seen on digital subtraction angiography, only three were identified by magnetic resonance angiography. We conclude that magnetic resonance angiography has great accuracy in depicting the main renal arteries and detecting clinically significant renal artery stenosis; however, the identification of accessory renal arteries is suboptimal and should be improved.

Summary: in this; study we examined the effects of long-term treatment of 19 patients with primary hypertension with the sr adrenoceptor antagonist atenolol on norepinephrine and epi­ nephrine kinetics, at rest and during sympathoadrenal stimula­ tion by lower body negative pressure. Norepinephrine and epinephrine kinetics were measured by using the radioisotopedi luti on technique by steady-state infusion of tritiated norepi­ nephrine and epinephrine. The patients were studied before and at the end of 3 months of treatment with atenolol (50 or 100 mg daily). A control group of four normotensive subjects was stud­ ied before and after 3 months without any drug treatment. In this group, only arterial blood samples were collected without infu­ sion of the tritiated catecholamines. Atenolol decreased blood pressure and heart rate, but forearm vascular resistance was not affected by atenolol. During atenolol, baseline arterial plasma epinephrine decreased from 0.23 ± O.02 to U.17 ± O.Oi nM (p < 0,05), and this was accompanied by a decrease in total body ep­ inephrine spillover from 0,50 ± 0.05 to 0.35 ± 0.04 nmol/min (p < 0.05), In the control group, arterial plasma epinephrine had not decreased after 3 months. In addition, the increment of arterial plasma epinephrine during lower body negative pressure at-40 mm Hg was attenuated during atenolol. Atenolol had no effect on total body and forearm norepinephrine spillover rates, either at rest or during lower body negative pressure. Clearance ivtes of epinephrine and norepinephrine were not significantly ef­ fected by atenolol. These results suggest that treatment of pa­ tients with primary hypertension with the s j-adrenoceptor blocker atenolol inhibits the adrenomedullary secretion of epi­ nephrine, but it does not affect the biochemical indices of sympathoneural activity, It remains speculative whether this selec­ tive effect of atenolol on epinephrine secretion contributes to its hypotensive action and to its cardioprotective effects in the long term. KeyWords: s (-Adrenergic— Sympathoadrenal activity— Hypertension— Catecholamines.

1. This review focuses on the extracellular actions of ATP and adenosine, and in particular their role in cardiovascular regulation. 2. ATP serves as a co-transmitter within the sympathetic nervous system, and is also released from endothelium and aggregating thrombocytes. ATP acts on P2x purinoceptors on vascular smooth muscle cells to induce vasoconstriction. Stimulation of P2y purinoceptors on endothelial cells releases endothelium-derived relaxing factors and causes vasodilatation. This dual action of ATP may have pathophysiological importance by inducing vasospasm at sites of impaired endothelial function and thrombus formation. 3. Adenosine is generated by enzymic degradation of ATP. Its formation is enhanced during ischaemia. Adenosine inhibits noradrenaline release from sympathetic nerve endings, causes vasodilatation via endothelium-dependent and endothelium-independent actions, has important anti-arrhythmic properties and prevents deleterious sequelae of ischaemia. In humans, adenosine evokes a sympatho-excitatory reflex mediated by chemically sensitive receptors and afferent nerves in the kidney, heart and forearm. This reflex may be active during exercise and ischaemia and, because of its potential adverse consequences, it should be considered when developing new therapies to potentiate the anti-ischaemic actions of endogenous adenosine in humans. Adenosine appears to mediate ischaemia-induced pain; a reduced sensitivity to adenosine may underlie silent ischaemia. 4. New drugs that interact with adenosine formation or degradation or with adenosine receptors are under development. These have potential therapeutic application in the treatment of ischaemia and other circulatory disorders.

Systemic hyperinsulinemia induces vasodilation in human skeletal muscle. This vasodilation contributes to insulin-stimulated glucose uptake and has been found to be reduced in various insulin-resistant states. The mechanism of the effect of insulin on vascular tone is not completely understood. We hypothesized that activation of the sodium-potassium pump (Na + ,K + -ATPase) located in endothelial or smooth muscle cells would be involved in the insulin-mediated vasodilation. Therefore, in 24 healthy, nonsmoking, nonobese, normotensive volunteers, we infused ouabain, a specific inhibitor of Na + ,K + -ATPase, into the brachial artery before and during euglycemic hyperinsulinemia. As expected, insulin (systemic concentrations, approximately 700 [low] and 1400 [high] pmol·L −1 ) induced vasodilation in the control arm (forearm blood flow [FBF, plethysmography] from 1.6±0.2 to 2.1±0.4 mL·dL −1 ·min −1 [low insulin] and from 1.6±0.2 to 2.1±0.2 [high insulin], P −1 ·min −1 [low] and from 1.3±0.1 to 1.3±0.1 [high], P =NS). Ouabain-induced increases in forearm potassium release were partly reversed by insulin. To investigate whether the mechanism of action could be at the endothelial level, we infused N G -monomethyl- l -arginine (L-NMMA), an inhibitor of endothelial nitric oxide synthase (0.05, 0.1, and 0.2 mg·dL −1 ·min −1 ) intra-arterially in 12 subjects and induced a clear dose-dependent decrease of FBF from 1.7±0.2 to 1.2±0.1 mL·dL −1 ·min −1 ( P −1 ·min −1 , n=6, P =.66). These results demonstrate that insulin induces vasodilation by stimulation of Na + ,K + -ATPase. This activation of Na + ,K + -ATPase could occur at the level of the endothelium rather than that of vascular smooth muscle and contributes to the endothelium-dependent vasodilator response to insulin.

Summary: The relation betw een insulin resistance/ hyperinsulinemia and cardiovascular disease may be re­ lated to one of the cardiovascular effects of insulin. In acute experiments in humans, systemic euglycemic hy- perinsulinemia induced vasodilation in skeletal muscle. Furthermore, the sympathetic nervous system is acti­ vated, although this does not lead to increase in blood pressure (BP). We hypothesized that insulin could induce vasodilation either by reduction of a- or by augmentation of p-adrenergic responsiveness. The effect of insulin in­ fusion into the brachial artery (regional forearm hyperin­ sulinemia; venous insulin concentration —500 pM) on forearm blood flow (FBF: plethysmography) was studied. Responses to the a-adrenoceptor-mediated vasoconstric­ tor norepinephrine (NE: once with and once without the p- adrenoceptor antagonist propranolol, 2 x n = 12; 9 par­ ticipated in both), and to the p-adrenoceptor-mediated vasodilator isoproterenol (n = 12 ) were measured before and during local hyperinsulinemia. Time/control studies (n = 6) were performed. Insulin alone induced vasodila­ tion, as indicated by an increase in FBF'ratio (infused/ control arm) from 1 .2 ± 0 .1 to 1 .6 ± 0 .2 , p = 0.009. Increasing dosages of N E (1.25 to 240 ng * d l ' 1 • m l ' 1) induced vasoconstriction that was more pronounced dur­ ing concomitant propranolol infusion (p < 0 .0 0 1 ), indicat­ ing a dose-dependent vasodilatory component in the ef­ fect of NE. Isoproterenol (ISO 0.03 to 10 ng * dl~* ' ini'"1), a pure p-adrenoceptor agonist, induced vasodilation. The percentage changes of FBF-ratio during NE + propran­ olol were similar and not significantly different before and during hyperinsulinemia. The same was true of the re­ sponse to N E alone and the response to ISO. Neither was the intrinsic p-agonist component of N E influenced by insulin. Repeated NE infusion showed no time- or vehicle effect. We conclude that regional hyperinsulinemia in the physiological range induces local vasodilation in the skel­ etal muscle vascular bed, but this vasodilation is not me­ diated through modulation of a- or p-adrenergic respon­ siven ess. Key Words: Insulin— a-A d ren ocep tor— p- Adrenoceptor— V as odilation.

An HPLC separation method combined with fluorometric detection was extended to enable simultaneous assessment of plasma 3H-labeled and endogenous epinephrine (E) and norepinephrine (NE). Forearm fractional extraction (FFE) of 3H-labeled E and NE and of endogenous E was measured in 40 healthy volunteers who were receiving a continuous infusion of 3H-labeled E and NE. Concentrations of arterial and venous E were 26.8 +/- 1.95 (mean +/- SE) and 6.8 +/- 0.75 ng/L, respectively. Arterial and venous NE and dopamine (DA) were also measured, with respective values of 140.7 +/- 8.5 and 192.1 +/- 15.1 for NE, and 13.1 +/- 0.78 and 11.3 +/- 0.70 ng/L for DA. The FFE of 3H-labeled E was slightly but significantly higher (0.790 +/- 0.016) than the that of either 3H-labeled NE or endogenous E (0.748 +/- 0.0146 and 0.745 +/- 0.0185, respectively; P < 0.001), the correlations being highly significant (r = 0.80, P < 0.001) in both cases. The small difference between the FFE of E and of 3H-labeled E allows the calculation of the apparent spillover of E. However, this spillover was negligible compared with forearm NE spillover (0.0112 +/- 0.0031 vs 1.369 +/- 0.128 ng/L per minute. The high sensitivity of this measurement of venous E widens the possibilities for studying E kinetics under physiological conditions.

In 6 healthy male volunteers a placebo-controlled, double-blind, randomized , crossover trial was done to assess the ejject of 1, 2, 4, and 6 mg o/ draflazine, a specific nucleoside transport inhibitor, on ventilation. Draflazine increased thoracic excursions dose-dependent ly by maximally (median with 95% confidence interval) 114.0% (38.3-184.8%) with­ out affecting breathing rate. Ex vivo adenosine transport was inhibited by 0% (0-1% ) after placebo, and 70% (59-74%), 81% (76-85%), 90% (86-93%), and 93% (90-96% ) after the 4 increasing draflazine dosages, respectively (P < ,05 for each draflazine dosage ver­ sus placebo]. These results indicate that endogenously released adenosine m ay play a role in the regulation of ventilation.

In this study, we investigated the vasoactive effects of the alkylxanthine pentoxifylline and its interaction with the nucleoside adenosine in the forearm skeletal muscle vascular bed of 18 normotensive healthy volunteers. Pentoxifylline infusion into the brachial artery in dosages of 100, 300, and 1,000 micrograms/100 ml forearm volume (FAV)/min, induced increments of forearm blood flow (FBF) of 41 +/- 6, 125 +/- 22, and 295 +/- 57%, respectively (n = 12). Calculated forearm vascular resistance (FVR) showed a dose-dependent decrease during pentoxifylline infusion. Concomitant administration of caffeine (100 micrograms/100 ml/min), an adenosine antagonist, did not attenuate the vasodilator response to pentoxifylline (n = 6). Intraarterial (i.a.) infusion of adenosine alone (0.75, 1.5, 3.0, and 4.5 micrograms/100 ml/min) induced a dose-dependent forearm vasodilator response. Concomitant infusion of pentoxifylline (100 micrograms/100 ml/min) did not cause a convincing potentiation of the forearm vasodilator effect of adenosine. This study demonstrates that pentoxifylline induces vasodilation in human forearm skeletal muscle vascular bed of healthy young volunteers. This vasodilator response occurred at concentrations that are probably much higher than those achieved with oral treatment with pentoxifylline. Our data further suggest that pentoxifylline-induced vasodilation is not mediated by adenosine receptor stimulation, but may result from inhibition of the enzyme phosphodiesterase (PDE).

Objective: To compare the sensitivity to atrial natriuretic peptide (ANP) in young and elderly subjects. Design: Double-blind, random-order, placebo-controlled study using two different rates of ANP infusion. Subjects: Eight healthy young (23 ± 3 years, mean ± SD) and eight healthy elderly (76 ± 4 years) subjects recruited from the general population. Measurement: Plasma cyclic guanosine monophosphate (cGMP, the second messenger of ANP) levels reflecting the sensitivity of biologically active ANP receptors. Results: Baseline ANP levels were higher and rose to a greater extent in the elderly both during low- (0.25 μg/min) and high-dose (2.0 μg/min) infusion of ANP. Plasma levels of cGMP rose in proportion to the increase in ANP. When the rise in cGMP levels was related to the increase in ANP levels (expressed as nmol/L per 100 pg/mL ANP increase), no difference was found between young and elderly subjects. Conclusion: The ability of elderly subjects to increase cGMP in response to exogenous ANP is similar to that of young subjects. This may reflect a similar sensitivity of the target organs towards ANP. However, because of lower clearance in the elderly, a similar dose of ANP results in a greater elevation of ANP and cGMP levels and hence induces a greater effect.

In a placebo-controlled, double-blind randomized design, we investigated the cardiovascular interaction between caffeine (250 mg intravenously) and nicotine (4 mg chewing gum) in 10 healthy volunteers, both under baseline conditions and during physical and mental stress (standing up and mental arithmetic). Caffeine alone induced a significant increase in blood pressure associated with a decrease in heart rate, whereas nicotine alone increased both blood pressure and heart rate. The combination of caffeine and nicotine increased systolic and diastolic blood pressure by 10.8 +/- 2.0 and 12.4 +/- 1.9 mm Hg, respectively. This pressor response did not differ significantly from the calculated additive effects of caffeine and nicotine on blood pressure, measuring 12.9 +/- 2.0 and 14.2 +/- 2.1 mm Hg, respectively. Heart rate and forearm blood flow also showed a similar response when the combination of caffeine and nicotine was compared with the calculated sum. During physical stress (standing up), blood pressure, heart rate, and plasma catecholamines increased in the placebo test. The pressor response to standing up was less pronounced after the combination of caffeine and nicotine compared with the sum of the separate effects (combination versus sum: delta diastolic blood pressure, 24.7 +/- 1.9 versus 35.2 +/- 2.6 mm Hg [p < 0.01]; delta mean arterial pressure, 22.1 +/- 2.0 mm Hg versus 28.6 +/- 1.6 mm Hg [p < 0.05]). The plasma catecholamine response did not differ between the combination and the sum of both drugs. During mental arithmetic, blood pressure, heart rate, and forearm blood flow increased in the placebo test. The forearm vasodilator response to mental stress was attenuated by the combination of caffeine and nicotine compared with the sum of both drugs (combination versus sum: delta forearm blood flow, -0.1 +/- 0.3 versus 1.4 +/- 0.5 ml/100 ml/min [p < 0.05]). We conclude that the combined administration of caffeine and nicotine shows additive effects on cardiovascular parameters during baseline conditions but less than additive effects during sympathoadrenal stimulation.

1. Cigarette smoking is one of the major risk factors for the development of atherosclerosis. It is not clear, however, whether chronic cigarette smoking impairs the normal physiological function of the endothelium before the development of morphological vascular lesions. To test this, we investigated endothelium-dependent vascular relaxation in young habitual smoking subjects. 2. In 11 non-smokers and 10 habitual smokers we measured the changes in bilateral forearm blood flow, arterial blood pressure and forearm vascular resistance (ratio between mean arterial blood pressure and forearm blood flow) during three interventions: postocclusive forearm hyperaemia, intrabrachial infusion of methacholine which causes vasodilatation by stimulating the release of endothelium-dependent relaxing factor, and intrabrachial infusion of sodium nitroprusside which causes vasodilatation independently from the endothelium by a direct effect on the vascular smooth muscle wall. 3. During infusion of the highest dose of methacholine, forearm vascular resistance decreased by 91.7 ± 1.4% in the smokers and by 89.9 ± 1.8% in the non-smokers. During infusion of sodium nitroprusside, forearm vascular resistance decreased by 80.0 ± 3.8% in the smokers as compared with 80.7 ± 6.1% in the non-smokers. There was no difference in basal forearm vascular resistance or in post-ischaemic reactive hyperaemia between smokers and non-smokers. Thus, vasodilatation induced by both methacholine and sodium nitroprusside was not significantly different between smokers and non-smokers. 4. We conclude that in young habitual cigarette smokers the endothelium-dependent vasodilatation in the forearm seems to be preserved, suggesting that habitual smoking does not result in permanent endothelial dysfunction in the human forearm.

Introduction. Renovascular hypertension (RVH) is defined as the elevation of arterial pressure precipitated by a hemodynamically significant stenosis of a renal artery or arteries (that is, stenosis caliber greater than 75% of the vessel lumen or than 50% with post-stenotic dilation). When the lesion affects both renal arteries or a single functioning kidney and is accompanied by renal failure (plasma creatinine concentration above 1.5 mg/dl), it is called ischemic nephropathy (1,2). The rate of renovascular hypertension (RVH) is less than 1% when a mild-moderate hypertension population is assessed but this increases according to the severity of the hypertension and population age (3). In 4,429 patients with arterial hypertension, Anderson et al. (4) found a prevalence of 3.1%, (2.7% attributed to atherosclerosis and 0.4% to fibromuscular dysplasia). Screening test. Signs and symptoms which point to RVH are: sudden onset of hypertension, especially in young ages subjects a particularly in women (due to fibrodysplastic lesion); the existence of severe hypertension in males over 60 years, with signs of atherosclerosis in other vascular territories (5-7); hypertension and abdominal bruit; grade III retinopathy in 25%-40% of the patients (8), elevation of serum creatinine after the administration of angiotensin converting enzyme (ACE) inhibitor (9-10); episodes of cardiac failure and acute pulmonary edema (11); hypertension refractory to treatment with >3 antihypertensive drugs. In all of these patients, the existence of RVH should be suspected. Although the renal arteriography is the "gold standard" for the diagnosis of RVH, it is an invasive method with possible complications so several non-invasive procedures can be used for the first diagnostic approximation. Those procedures which are used the most are the: i Renal scintigraphy following ACE inhibitor: Its sensitivity and specificity is 78% - 90% and 88% - 95% respectively (12-14), which decreases when there is bilateral lesion and renal insufficiency.

Item does not contain fulltext OBJECTIVE: To show that different methods of data analysis affect the grading that blood pressure measuring devices achieve according to the British Hypertension Society (BHS)-protocol. METHODS: Based on the somewhat unclear description of the exact method of data analysis in the BHS-protocol four different methods can be discerned. The effect on the grading-results is calculated for these four different options. RESULTS AND CONCLUSIONS: It is shown that using these four different options the achieved grade can range for diastolic blood pressure from C (option 1) to almost A (option 4) and for systolic blood pressure from D (option 1) to B (option 4). Different researchers may well have used different methods. Option 1 is the method that should be used. Also it is stated that the systematic error and the standard deviation of differences (SDD) are measures that give more insight to describe a device's performance. Calculating the grades after correction for the systematic error shows its influence and that of the SDD on the reported accuracy of a blood pressure measuring device.

To the Editor: We welcomed the article from Myers et al1 on automated office blood pressure (AOBP) measurement. It is well known that the differences between routine blood pressure (BP) measurements taken by health professionals in daily practice and BP measurements taken by well-trained observers within the framework of scientific studies are impressive. Because of this, routine BP measurement is of limited value. The studies on AOBP open the way in realizing a valid BP …

In a double-blind, randomized, placebo-controlled study, the authors investigated the effects of different beta-adrenoceptor blocking drugs on the peripheral circulation. A single intravenous injection of the nonselective beta-blocker propranolol (0.20 mg/kg), the beta 1-selective adrenoceptor blocker metoprolol (0.25 mg/kg), and the nonselective beta-blocker with partial agonistic activity (PAA) pindolol (0.04 mg/kg) and of placebo (saline) was given to eight patients with a primary Raynaud's phenomenon and to nine untreated patients with primary hypertension. The authors measured finger skin temperature (FST), and laser Doppler estimated finger skin blood flux (LDF) before, during, and after a standardized finger cooling test, performed 25 minutes after the administration of the drugs. In both patients groups propranolol, metoprolol, and pindolol had no significant effect on FST and LDF in the first 25 minutes after administration both in comparison to baseline value and to placebo. Also, no significant differences were found in the recoveries of FST and LDF after cold challenge between all drugs and placebo in both groups. The authors conclude that no adverse effect of any type of beta-adrenoceptor blocker in comparison to placebo could be detected after a single administration on both the baseline finger skin perfusion and the recovery after cold-induced vasoconstriction. In addition, the authors could not demonstrate a favorable effect of beta 1-selectivity or PAA in comparison to a nonselective beta-adrenoceptor blocker without PAA, in any group.

OBJECTIVE: Studies directly comparing the associations of intima-media thickness with blood pressure (BP) on manual sphygmomanometric blood pressure measurement (SBPM) and 24-h ambulatory blood pressure measurement (ABPM) are scarce and have a cross-sectional design. METHODS: At baseline, we measured systolic and diastolic blood pressures, pulse pressure, and mean arterial pressure in 532 randomly recruited patients (women, 48.3%; mean age, 38.9 years) by SBPM and ABPM. SBPM was the average of five consecutive readings obtained by trained observers at the patients' homes. We measured carotid intima-media thickness (CIMT) and femoral intima-media thickness (FIMT) by a wall-tracking ultrasound system, 26 months (median) after BP measurement (interquartile range, 21-29 months). We adjusted all analyses for observer, sex, age, BMI, smoking, and total/high-density lipoprotein-cholesterol ratio. RESULTS: The multivariable-adjusted associations of CIMT and FIMT with all BP components on SBPM were not significant (P >or= 0.12). In multivariable-adjusted models, CIMT increased with 24-h systolic blood pressure (effect size per SD increase, +0.131 mm; P = 0.003) and 24-h pulse pressure (+0.139 mm; P = 0.001), whereas FIMT increased with 24-h diastolic blood pressure (+0.091 mm; P = 0.03) and 24-h mean arterial pressure (+0.090 mm; P = 0.04). Models including the ambulatory blood pressure components additionally adjusted for SBPM and more covariables than those listed above were confirmatory. CONCLUSION: In a general population, BP on ABPM predicts CIMT and FIMT over and beyond highly standardized SBPM. At the elastic carotid artery, CIMT increased predominantly with the pulsatile component of BP, whereas at the muscular femoral artery, FIMT increased with the steady component of BP. ispartof: Journal of Hypertension vol:27 issue:4 pages:813-821 ispartof: location:Netherlands status: published

The aim of this study was to investigate whether caffeine stimulates selectively renal vein renin levels at the side of unilateral stenosis in patients with renovascular hypertension. In this study seven of the involved patients had renal arterial stenosis and four had no stenosis. Four of the seven patients with a stenosis had retrospectively-proven renovascular hypertension. Renal vein renin sampling was performed before and after intravenous administration of caffeine. Caffeine did not induce any consistent effect on plasma renin activity in the renal veins, either on the stenotic side or on the contralateral side in patients with renovascular hypertension. There were no consistent caffeine mediated changes in systemic plasma renin activity.

1. α2-Adrenoceptors on platelet membranes and β2-adrenoceptors on lymphocytes were studied in 24 patients with primary Raynaud's phenomenon and in 24 age- and sex-matched control subjects. In two subgroups, a standardized mental arithmetic test and a finger-cooling test were performed. 2. Baseline blood pressure, heart rate and forearm blood flow did not differ between the two groups. 3. Baseline skin microcirculation (laser Doppler flux) was decreased in primary Raynaud's phenomenon (19 ± 15 arbitrary units) compared with control subjects (33 ± 14 arbitrary units) (P 4. Baseline plasma noradrenaline concentration (2.0011.44 versus 1.16 ± 0.36 nmol/l) and α2-adrenoceptor density (301 ± 119 versus 210 ± 82 fmol/mg) were increased in patients with primary Raynaud's phenomenon in comparison with the control subjects. The α2-adrenoceptor density/β2-adrenoceptor density ratio in patients with primary Raynaud's phenomenon was, with a value of 0.37 ± 0.04, higher than in the control subjects, where a value of 0.25 ± 0.02 was measured (P 5. Whereas during the finger-cooling test no differences were seen in the responses of the parameters measured, the mental arithmetic test induced an increase in laser Doppler flux in patients with primary Raynaud's phenomenon and a decrease in the control group. The increase of plasma noradrenaline concentration during the mental arithmetic test was only statistically significant in the control group. 6. The results are discussed in relation to the two common theories concerning the aetiology of primary Raynaud's phenomenon: a local vascular defect and a primary sympathetic hyperfunction.

BACKGROUND: We studied the repeatability of the ambulatory arterial stiffness index (AASI), which can be computed from 24-h blood pressure (BP) recordings as unity minus the regression slope of diastolic on systolic BP. METHODS: One hundred and fifty-two hypertensive outpatients recruited in Nijmegen (mean age = 46.2 years; 76.3% with systolic and diastolic hypertension) and 145 patients enrolled in the Systolic Hypertension in Europe (Syst-Eur) trial (71.0 years) underwent 24-h BP monitoring at a median interval of 8 and 31 days, respectively. We used the repeatability coefficient, which is twice the SD of the within-participant differences between repeat recordings, and expressed it as a percentage of four times the SD of the mean of the paired measurements. RESULTS: Mean AASI (crude or derived by time-weighted or robust regression) and 24-h pulse pressure (PP) were similar on repeat recordings in both cohorts. In Nijmegen patients, repeatability coefficients of AASI and PP were approximately 50%. In Syst-Eur trial patients, repeatability coefficient was approximately 60% for AASI and approximately 40% for PP. For comparison, repeatability coefficients for 24-h systolic and diastolic BP were approximately 30%. Differences in AASI between paired recordings were correlated with differences in the goodness of fit (r2) of the AASI regression line as well as with differences in the night-to-day BP ratio. However, in sensitivity analyses stratified for type of hypertension, r2, or dipping status, repeatability coefficients for AASI did not widely depart from 50 to 60% range. CONCLUSION: Estimates of mean AASI were not different between repeat recordings, and repeatability coefficients were within the 50-60% range. ispartof: Journal of Hypertension vol:26 issue:10 pages:1993-2000 ispartof: location:Netherlands status: published

Contains fulltext : 70451.pdf (Publisher’s version ) (Closed access) WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: Insufficient drug adherence is an important reason for inadequate blood pressure control. Currently, methods that measure drug adherence objectively are lacking. Objective methods are needed to help improve blood pressure control and outcome in hypertensive patients. WHAT THIS STUDY ADDS: Potassium bromide added to antihypertensive drugs can be used to monitor drug adherence in individual patients. However, although this method is objective, it is rather time-, cost- and work-consuming. AIMS Adherence to antihypertensive medication is essential for adequate long-term control of blood pressure (BP). This study investigated different methods of measuring adherence in hypertensive patients. METHODS: Patients were included if BP was insufficiently controlled on monotherapy. After a placebo period patients were treated with trandolapril 2 mg/verapamil SR 180 mg (TV). BP was determined using a mercury sphygmomanometer and ambulatory BP monitoring. Adherence was measured by capsule counting, electronic registration of pill-box openings and by measuring serum bromide concentrations. Potassium bromide was added to each TV capsule. RESULTS: Thirty patients participated in the study. Treatment with TV significantly lowered office BP and ambulatory BP. Results for electronic monitoring and adherence based on bromide measurements were comparable. Adherence was slightly higher when assessed by capsule counting. CONCLUSIONS: Measuring serum bromide concentrations may be suitable for assessment of adherence to drug therapy giving comparable results to electronic monitoring. Using capsule counting, electronic monitoring and measurement of bromide concentrations, nonadherent patients were identified.

Contains fulltext : 69385.pdf (Publisher’s version ) (Closed access) OBJECTIVE: To determine which physiological mechanism is responsible for the blood pressure increase during leg crossing at knee-level in the sitting position. METHODS: Finger blood pressure was measured with the Finometer in 102 participants (47 men) before and during leg crossing: 24 treated hypertensive patients, 50 diabetic individuals (25 with and 25 without antihypertensive medication) and 28 healthy volunteers. Mean age, 53 +/- 15 years (range 21-82 years). All participants crossed their legs at knee-level, with the upper part of the popliteal fossa on the suprapatellar bursa, in the sitting position. Differences in mean blood pressure, cardiac output, stroke volume, heart rate and total peripheral resistance were assessed with legs crossed versus legs uncrossed. RESULTS: Mean blood pressure [+3.3 +/- 5.5 mmHg; 95% confidence interval (CI) = 2.7-3.8], stroke volume (+7.6 +/- 5.4 ml; 95% CI = 6.7-8.6) and cardiac output (+0.4 +/- 0.9 l/min; 95% CI = 0.3-0.5) were significantly higher with legs crossed than in the uncrossed position, while the heart rate (-1.8 +/- 3.9 beats/min; 95% CI = -2.2 to -1.4) was significantly lower. Total peripheral resistance did not differ significantly (-0.01 +/- 0.16 AU; 95% CI = -0.03 to 0.00). The largest differences occurred in the hypertensive diabetic individuals, the smallest in the healthy volunteers. The changes were similar in men and women. There were no significant correlations in the total group between the differences of the hemodynamic variables and sex, age, body mass index or leg circumference. CONCLUSION: The study shows that higher blood pressure with legs in the crossed position is due to higher cardiac output and not to a higher total peripheral resistance.

Because levels of plasma atrial natriuretic factor (ANF) increase with advancing age, a diminished hemodynamic responsiveness to ANF in the elderly has been hypothesized in the literature. Therefore hemodynamic effects after two infusion rates (0.25 and 2.0 μg/min) of atrial natriuretic factor (99-126) were investigated in young (n = 8) and elderly (n = 9) volunteers in a double-blind, randomized, and placebo-controlled protocol. After low-rate infusion, ANF concentrations increased to the upper normal range, and only minor effects were observed. In contrast, high-rate infusion resulted in a decrease in blood pressure and forearm vascular resistance, whereas an increase in heart rate was observed in both groups. Between young and elderly subjects, a significant difference was observed in the ANF-induced decrease in systolic blood pressure (mean ± SD, − 4% ± 4% versus − 12% ± 7%, p < 0.05) and mean arterial pressure (− 6% ± 5% versus −11% ± 4%, p < 0.05) during the high rate infusion. When compared with the concentrations of the young subjects, the ANF concentrations reached at both ANF dosages were higher in the elderly subjects; this was the result of a diminished ANF clearance in the elderly subjects. After correction of the changes of systolic blood pressure and mean arterial pressure for the higher ANF levels reached within this elderly group, no difference between young and elderly subjects remained. We conclude that a diminished cardiovascular responsiveness to ANF with advancing age could not be demonstrated. In contrast, the high-rate infusion of ANF induced an increased hemodynamic response in the elderly subjects, but this seems to be the result of the higher ANF levels reached within this group. Clinical Pharmacology and Therapeutics (1990) 48, 179–188; doi:10.1038/clpt.1990.133

Background: Masked hypertension (MH) is defined as a normal blood pressure in the physician's office and an elevated blood pressure when measured out-of-office. The cause of MH may be termed the masked hypertension effect (MHE), and is not restricted to blood-pressure (BP) values around the thresholds for normal BP. We investigated the prevalence and persistence of MH and MHE in patients who were being treated for high BP and who had been followed for a period of 1 year.Methods: One hundred and sixty-one treated hypertensive patients underwent office blood-pressure measurements (OBPMs) at seven visits and self-performed blood-pressure measurements (SBPMs) for I week before each visit over a period of 1 year. All measurements were performed with the same type of automatic device. At each visit. MH was determined according to the European Society of Hypertension definition (OBPM, = 135 mm Hg or 85 mm Hg). In addition, we determined prevalences of MHE at 5/3 mm Hg (SBPM exceeds OBPM by 5 mm Hg systolic and 3 mm Hg diastolic), and MHE at 10/6 mm Hg (SBPM exceeds OBPM by 10 mm Hg systolic and 6 mm Hg diastolic), respectively.Results: During the entire study, 50% of the patients had MH, and 40% had MHE at 5/3 mm Hg at least once. At four sequential OBPM visits, 2% consistently had MH, and 3% had MHE at 5/3 mm Hg or MHE at 10/6 mm Hg. The prevalence of MH increased with lower OBPM levels but remained rather constant for MHE at 5/3 mm Hg and MHE at 10/6 mm Hg. The persistence of MH and the MHE over time in individual patients was low.Conclusions: We conclude that MH and MHE at 5/3 mm Hg and MHE at 10/6 mm Hg commonly occur in treated patients, but are not persistent phenomena and probably result from an accidentally low OBPM value on one particular occasion. Am J Hypertens 2007;20: 1258-1265 (c) 2007 American Journal of Hypertension, Ltd.

Contains fulltext : 52290.pdf (Publisher’s version ) (Closed access) Masked hypertension (blood pressure that is normal in the physicians' office but elevated elsewhere) is a common phenomenon as prevalence among studies varies from 8 to 45% and is seen at all ages. large discrepancies, however, exist between studies that have dealt with masked hypertension. It is of high clinical importance as it is associated with higher target organ damage as compared with sustained normotension. Therefore more research should be determined. This paper provides an overview of current literature to improve knowledge about masked hypertension and about the cause of this phenomenon. In addition it provides some questions, which need to be answered for performing appropriate research into this subject in future.

To the Editor: In 2006, Li et al1 proposed the ambulatory arterial stiffness index (AASI) as a novel marker for arterial stiffness. AASI is derived from the linear relationship between systolic blood pressure and diastolic blood pressure observed using 24-hour ambulatory blood pressure monitoring. The literature published on this topic shows some large differences in the mean AASI between studies. In our opinion, these differences cannot be fully accounted for by differences in methodology and patient characteristics. The Table shows a review of important issues of methodology and …

Contains fulltext : 51446.pdf (Publisher’s version ) (Closed access) OBJECTIVE: To determine whether crossing of the legs at the knee or at the ankles during blood pressure measurement in sitting position has an effect on blood pressure. METHODS: One hundred and eleven patients, 60 women, mean age 52+/-17 years (19-80): 49 chronically treated hypertensives, 28 treated diabetics and 34 normotensives were measured by one trained investigator, with an oscillometric device (Omron 705CP) on the left arm. We looked for the difference of blood pressure with the ankle or the knee crossed versus the uncrossed position. RESULTS: Leg crossing at the knee during blood pressure measurement increased systolic blood pressure significantly by 6.7 (95% confidence interval 5.0-8.4) mmHg in the hypertensives and 7.9 (4.0-11.8) mmHg in the treated diabetics. Diastolic blood pressure increased by 2.3 (0.8-3.8) mmHg in the hypertensives and 1.7 (0.1-3.4) mmHg for the treated diabetics. Normotensive participants showed a smaller, though significant, increase of systolic blood pressure 2.7 (1.2-4.2) mmHg, but not significant for diastolic blood pressure, -0.1 (-1.5-1.3) mmHg, respectively. In all groups there was no effect of crossing the ankles on blood pressure. No differences were found between men and women. No significant correlation between the increase of the blood pressure when the knees were crossed and BMI, age or baseline blood pressure was present. CONCLUSIONS: Blood pressure increased when legs were crossed at the knee in the sitting position. No significant increase of blood pressure was found when crossing the legs at the ankles. Leg position during measurement of blood pressure should be standardized and mentioned in publications.

Contains fulltext : 50127.pdf (Publisher’s version ) (Closed access) OBJECTIVE: To investigate the prevalence and persistence of the white-coat effect (WCE) and white-coat hypertension (WCH) on multiple blood pressure measurement occasions in hypertensive patients with and without treatment. DESIGN: Essential hypertensive patients in whom we took office blood pressure measurements (OBPM) at eight visits (three readings per visit) performed self blood pressure measurements (SBPM) for 1 week prior to each visit (42 readings per week) over a period of 1 year. All measurements were performed with the same automatic device (Omron 705CP). In addition, 24-h ambulatory blood pressure monitoring (ABPM) was performed at the start and at the end of the study. At the start, patients did not use any medication but on subsequent visits they were treated on the basis of their SBPM values. WCH was defined as an OBPM-value > or = 140 and/or 90 mmHg and a SBPM or daytime ABPM value < 135/85 mmHg. This definition was used irrespective of treatment. We also determined the prevalence of a substantial WCE (OBPM 20 mmHg systolic or 10 mmHg diastolic higher than SBPM or daytime ABPM). SETTING: Patients were recruited at hospital or general practice. PATIENTS: A total of 163 mild-to-moderate essential hypertensive patients with a mean age of 56 years (56% males). RESULTS: At eight blood pressure (BP) measurement occasions, 75% of all patients had a substantial WCE at least once, while 57% had WCH at least once. One-third of the patients consistently had a substantial WCE and 14% consistently had WCH on three or more occasions The magnitude of the WCE was significantly related to the height of blood pressure in treated but not in untreated patients. CONCLUSION: In some patients, WCH or a substantial WCE occurs consistently on multiple OBPM visits. Especially in untreated patients, the magnitude of the WCE varies widely among individuals. These results support the incorporation of SBPM and/or ABPM into optimal management of hypertension, not only to prevent misdiagnosis in untreated patients but also to determine the need for adjusting antihypertensive therapy in treated subjects.

Contains fulltext : 50693.pdf (Publisher’s version ) (Open Access) CONTEXT: Cardiovascular disease is common and preventable. Primary care is the preferred setting for individual prevention and management. OBJECTIVE: This study analyzed the long-term outcome of cardiovascular risk in a family practice population. DESIGN: A longitudinal cohort analysis of cardiovascular outcome after 18 years, in participants of a randomized controlled trial (RCT) of cardiovascular prevention. In 1977, a RCT with cluster randomization at practice level assessed the effects of a 1-year preventive intervention in patients 20 to 50 years of age. Cardiovascular risk factors (smoking, body mass index, blood pressure, serum cholesterol, family history, and physical activity) were measured and intervention was a practice-nurse support for the follow-up of those at elevated risk. The control practices prescribed care as usual. Between 1994 and 1995, all participants were approached again, to analyze subsequent (cardiovascular) mortality and morbidity and their cardiovascular risk in a random sample. SETTING: The Nijmegen Academic Family Practices Network, The Netherlands. PARTICIPANTS: All participants (7092) of the 1977 screening for follow-up morbidity and mortality, 2600 for re-measurement risk factors. OUTCOME MEASURES: Cardiovascular risk factors; cardiovascular morbidity and mortality 1977-1995. RESULTS: Follow-up was achieved in 5945 participants (84%) and 2335 participated in the re-measurement (89%). No effects of the preventive intervention were found, but those initially at low risk profile were still so 18 years later. Risk of subsequent cardiovascular mortality and morbidity was related to baseline risk, but for women, the absolute risk was low in all risk strata and lower than predicted from international references. CONCLUSIONS: This study demonstrated the feasibility of family practice network research in pursuing longitudinal research. A single cardiovascular screening resulted in reliable risk assessment: those initially at low risk still were so after 18 years. Effects of a 1-year intensive intervention could no longer be demonstrated.

Contains fulltext : 51036.pdf (Publisher’s version ) (Closed access) OBJECTIVE: To determine how many self-measurements of blood pressure (BP) should be taken at home in order to obtain a reliable estimate of a patient's BP. DESIGN: Participants performed self blood pressure measurement (SBPM) for 7 days (triplicate morning and evening readings). In all of them, office blood pressure (three consecutive readings) and 24-h ambulatory blood pressure were obtained as well. Average SBPM values, obtained from several combinations of readings, were correlated with the results of ambulatory blood pressure measurement (ABPM). In addition, we assessed whether certain patient characteristics would influence such correlations. SETTING: Patients were recruited at hospital or general practice. PATIENTS: A total of 216 untreated hypertensive patients. RESULTS: The average SBPM value calculated from day 3 to day 7, omitting the first measurement of each morning and evening session, gave the best correlation with 24-h ABPM (r = 0.70). However, similar results were obtained from a SBPM value averaged from day 3 until 5 without the first measurement of each triplicate session. Overall, younger patients had significantly better correlations than older ones. Women had significantly better correlations with ABPM than men for systolic morning and daytime SBPM, whereas men had significantly better correlations for daytime and evening diastolic SBPM (P < 0.001). In addition, all correlations increased with lower systolic office blood pressure measurement (OBPM) values. CONCLUSIONS: A minimum number of 5 days of measurement is recommended to obtain a reliable estimate of a patient's usual BP. On each day, three consecutive morning and evening measurements should be performed. For calculating the average SBPM, the first 2 days and the first measurement of each triplicate measurements should be discarded. Moreover, patient characteristics may have an impact on the number of necessary self-measurements. However, because adhering to these recommendations will make SBPM a time-consuming procedure, this type of measurement should be performed only when a decision about starting or changing antihypertensive therapy is needed or in the case of special patient groups.

Contains fulltext : 49507.pdf (Publisher’s version ) (Closed access) OBJECTIVE: Several methods have been described to measure adherence to prescribed drug therapy. However, most of these have been shown to be inaccurate. Bromide is an anion that is readily absorbed in the gut and has an elimination half-life of about 12 days. In the present study, we investigated the pharmacokinetic properties of bromide with the objective to use it as a measure of drug adherence. METHODS: Three groups of each 8 healthy volunteers took 15, 24 or 30 mg potassium bromide, respectively, daily for 20 weeks. Serum concentrations of bromide were measured every two weeks. RESULTS: There was a linear relationship between the daily dosage taken and the mean increase of bromide concentration. In every group considerable inter-individual variability was seen. Correction for body weight resulted in an improved correlation between daily bromide dose and increase in concentration (r=0.78, p

Contains fulltext : 48129.pdf (Publisher’s version ) (Closed access) OBJECTIVE: To study the experiences and complaints of patients who underwent 24 h blood pressure monitoring. METHODS: Two groups of hypertensive patients of a tertiary outpatient clinic were asked to fill in a nine-item questionnaire about the side effects of ambulatory blood pressure monitoring (ABPM). The first group (n=75) used the auscultatory Oxford Medilog device (OM) and the second group (n=110) the oscillometric Spacelabs 90207 (SL). RESULTS: The OM showed significantly less error readings (OM versus SL, 9 versus 19%; P=0.005) but was also less tolerated by the subjects. Sleep disturbance was noted in 53% of the OM patients group in comparison with 18% in the SL group (P