The prevalence of renal artery stenosis among patients with diabetes mellitus.

BACKGROUND: Patients with diabetes mellitus (DM) have a high prevalence of atherosclerotic vascular lesions. It is therefore reasonable to assume that also the rate of renal artery stenosis (RAS) is higher. The presence of a RAS can have implications for the treatment of patients with diabetes mellitus and hypertension and renal impairment. Therefore it is important to be informed about the chance that a RAS is present among such patients. METHODS: We prospectively studied the prevalence of atherosclerotic renal artery stenosis (RAS) among patients with diabetes mellitus. Patients were included if they were diagnosed with DM and hypertension with or without impairment of renal function. If causes of renal disease other than DM or hypertension were more probable on the basis of biochemical data, then such patients were excluded. A magnetic resonance angiography (MRA) of the renal arteries was made in 54 included successive patients. PATIENT CHARACTERISTICS: mean age 59 ± 8.5 years (range 35 to 80). Eight patients had DM 1 and 46 DM 2. Mean BMI was 31.4 ± 5.6 kg/m(2). A RAS was present in 18 of the 54 (33%) patients, 3 patients had bilateral stenoses. Factors related to the presence of RAS were diastolic blood pressure, glomerular filtration rate and dyslipidaemia. CONCLUSION: In this group of diabetic patients with hypertension and or renal impairment the prevalence of RAS was 33%.

Clinical significance of low-grade renal artery stenosis.

BACKGROUND: Patients with a renal artery stenosis (RAS) >50% carry an increased risk for future cardiovascular (CV) events. Experimental literature on this topic suggests that this might as well be true for subjects with lower-grade RAS. METHODS: Recruitment in this longitudinal cohort study was conducted from 1982 to 2002 in a Dutch University Hospital. Included in this study were 301 hypertensive patients clinically suspected of having RAS. Study participants were radiologically classified as having no, a low-grade (<50% lumen narrowing) or high-grade (> or =50%) RAS. A predetermined composite CV end-point was defined as one of the following: myocardial infarction or 'objectified' angina pectoris, ischaemic stroke or death from any CV cause. Other end-points were the occurrence of CV complications, all-cause plus CV mortality and decline in renal function. RESULTS: During a median follow-up of 8.2 years, the incidence of the composite end-point totalled 79 events. After full adjustment in Cox models, a significant risk increase in high-grade [hazard ratio (HR) 2.81; P = 0.002] and low-grade RAS (HR 2.32; P = 0.038) was observed. Other end-points did not differ significantly between study groups. CONCLUSION: Hypertensive subjects with RAS of any extent, compared with hypertensives without RAS, carry a substantially increased risk for future CV events. Therefore, even in patients with low-grade RAS, aggressive pharmacological treatment strategies should be adopted as a preventive measure.

Multilayer compression bandaging in the acute phase of deep-vein thrombosis has no effect on the development of the post-thrombotic syndrome.

OBJECTIVE: The purpose of this randomized study was to evaluate the influence of immediate multilayer compression bandages before application of elastic stockings in the acute phase of deep-vein thrombosis (DVT) on development of the post-thrombotic syndrome (PTS). METHODS: Sixty-nine patients with acute symptomatic DVT were randomized to immediate bandaging (n = 34) or no bandaging (n = 35). After reduction of edema sized-to-fit elastic stockings were applied in all patients after 7-14 days. Follow-up visits and non-invasive examinations were planned after 7, 30 and 90 days and 1 year. Venous outflow resistance (VOR) was measured by strain gauge plethysmography. Thrombosis score (TS) and reflux were measured by duplex scanning. After one year patients were evaluated for clinical PTS using both the clinical scale of the CEAP classification and the Villalta score. RESULTS: Improvement of clinical symptoms and decrease of leg circumference was better on day 7 in the bandaging group, but after 1 and 3 months clinical symptoms had improved equally in both groups. In 7 patients in the no-bandaging group a bandage was applied after all because of persistent edema after 10 days. There were no differences in VOR, TS and reflux. Using the CEAP classification the incidence of PTS was 39% in patients with bandages and 42% in patients without bandages (RR 0.91, 95% CI 0.50-1.66). Using the Villalta score the incidence of PTS was resp. 29 and 33% (RR 0.87, 95% CI 0.41-1.8). There was no difference in severity of PTS. CONCLUSION: Immediate multilayer compression bandaging in the acute phase of DVT is effective in reducing edema and complaints in the first week, but has no effect on thrombus regression, valve incompetence and the development of clinical PTS after 1 year.

[Treatment of hypertension in people over 80 years should not be discontinued]. / Behandeling van hypertensie bij mensen boven de 80 jaar niet stopzetten.

The 'Hypertension in the very elderly trial' (HYVET) was designed to answer the question whether antihypertensive treatment reduces strokes (both fatal and non-fatal strokes) without increasing total mortality. A total of 3845 patients were assigned to active treatment or placebo. About 90% had a history of hypertension, 65% of which were being treated. At the start of the study all antihypertensive treatment was stopped and the subjects were randomized to either indapamide 1.5 mg with or without perindopril 2-4 mg or to identical looking placebo. After about 2 years the trial was discontinued for ethical reasons as there was less death from any cause in the intervention group. Blood pressure decreased with 30/13 mmHg in the treatment versus 15/7 mmHg in the placebo group. There was a 30% decrease of all strokes (p = 0.06) but a significant reduction in fatal strokes (p < 0.05). Unexpected was the 21% reduction in all-cause mortality (p < 0.02). The 23% reduction in the rate of cardiovascular death was not significant (p < 0.06). Heart failure and total cardiovascular events decreased (p < 0.001). There were fewer adverse effects in the treatment group (p = 0.001). In our opinion HYVET proves that antihypertensive medication should not be stopped when patients pass the age of 80 years. However, it remains to be established whether treatment should be started in new patients who present themselves with hypertension above the age of 80 years.

Does masked hypertension exist in healthy volunteers and apparently well-controlled hypertensive patients?

BACKGROUND: Home blood pressure (HB P) measurement is considered to reflect BP during the day better than office BP (OB P). But in some patients HB P is higher than OB P. This is called masked hypertension (MH). OBJECTIVE: To examine whether MH occurs in healthy volunteers and apparently well-controlled hypertensives. METHODS: 57 treated hypertensive patients and 31 healthy volunteers (27/22 men) participated. Mean age (+/- SD ) was 61 +/- 13 and 29 +/- 13 years, respectively. Patients were instructed to measure their BP twice daily for three days (3 readings each) with the Omron 705 CP device after at least 10 minutes rest in a comfortable sitting position. In the outpatient department, OB P was measured four times, in duplicate, every ten minutes by the physician using the same device and under similar conditions. RESULTS: Mean HB P of the treated hypertensive group was 146/84 +/- 18/10 mmHg, significantly higher than OB P 136/79 +/- 19/10 (p.

The effect of arginine vasopressin on endothelin production in the human forearm vascular bed.

OBJECTIVES: To study whether arginine vasopressin (AVP) can stimulate endothelin production and/or release in vivo, in the human forearm vasculature. DESIGN: The effect of the infusion of AVP into the brachial artery on endothelin production across the human forearm vascular bed was studied in healthy male volunteers, and was compared with intra-arterial infusion of placebo. In another group the effects of AVP on endothelin production were studied after a prior infusion of L-NG-monomethyl-arginine (L-NMMA), a nitric oxide-synthase inhibitor. In a fourth group the effect of L-NMMA alone, without AVP infusion, on endothelin production was studied. METHODS: We measured the effects of AVP, placebo, L-NMMA followed by AVP and L-NMMA followed by placebo on arterial and venous endothelin concentrations in the forearm of four groups, each consisting of five healthy male volunteers. Forearm blood flow was measured by strain gauge plethysmography. The endothelin production was calculated as forearm blood flow times (venous - arterial) endothelin concentration. RESULTS: The group infused with L-NMMA followed by infusion of 8 ng AVP/min per dl forearm volume showed a significant rise in endothelin production from 1.3 (1.8) to 5.0 (2.0) pg/min/dl at 15 minutes (p<0.05, ANOVA). This rise in endothelin production was also significantly different from the endothelin production at 15 minutes in the other three groups (p<0.01, ANOVA). CONCLUSION: In healthy male volunteers intra-arterial infusion of AVP induced a rise in endothelin production in the forearm within 15 minutes, but only after prior infusion of L-NMMA. This observation suggests that the AVP-induced production of nitric oxide offsets AVP-mediated release of endothelin.

Two years of smoking cessation does not reduce arterial wall thickness and stiffness.

BACKGROUND: Smoking cessation rapidly reduces cardiovascular risk. The pathophysiological mechanisms involved are still being debated. We measured structural and functional arterial wall properties of the femoral and carotid arteries after smoking cessation to investigate their possible role in cardiovascular risk reduction. METHODS: Out of 127 smokers, 33 proved to stop smoking for two years. They were compared with 50 nonsmokers and 55 persistent smokers in a prospective study. Cross-sectional compliance and distensibility coefficients as well as intima-media thickness of both carotid arteries and of the right common femoral artery were measured ultrasonographically at baseline and 3, 6, 12 and 24 months after smoking cessation. The nonsmoking and persistent smokers group were measured twice at an interval of 24 months. RESULTS: Persistent smoking and two years of smoking cessation did not affect cross-sectional compliance and distensibility coefficients. Although at baseline intimal-medial layers were thicker in smokers, the change over time in intima-media thickness did not differ significantly between all three groups. CONCLUSION: Two years of smoking cessation was not accompanied by a slower progression or a regression in intima-media thickness nor by an improved cross-sectional compliance or distensiblity coefficient. Nevertheless, smoking cessation should be recommended as it reduces cardiovascular risk rapidly after smoking cessation.

The StethoDop: a Doppler stethoscope attachment for investigation of arterial and venous insufficiency of the lower extremities.

BACKGROUND: The aim of the current study was to investigate whether the StethoDop can serve as a valid and reproducible instrument for measuring the ankle-brachial index (ABI) and assessing venous reflux, even when used by inexperienced investigators, in comparison with the classic Doppler. METHODS: I) During four weeks, four ankle-brachial index (ABI) measurements were performed on 44 patients: one measurement with the classic Doppler by an experienced investigator, one with the classic Doppler by an inexperienced investigator and two measurements with the StethoDop by the inexperienced investigator. II) 36 patients were screened for venous insufficiency by detecting venous reflux with the StethoDop and classic Doppler at the saphenofemoral and saphenopoplitial junctions by an inexperienced investigator. The results were compared with the results of the duplex as gold standard and with the results of the examination by an experienced dermatologist with the classic Doppler. RESULTS: I) The confidence interval of ABI measurement for both the classic Doppler and the StethoDop by the inexperienced investigator was within an acceptable +/- 0.21 interval of significant change. II) For venous reflux determination, the overall sensitivity and specificity of the StethoDop were comparable with the sensitivity and specificity of the classic Doppler: sensitivity 76.0 and 75.0%, specificity 94.8 and 94.2%, respectively. The positive predictive value of the StethoDop, compared with the duplex, was 87.5%; the negative predictive value was 90.0%. CONCLUSION: I) For ABI measurement, the StethoDop is a valid instrument with reproducible results, even when used by inexperienced investigators. II) For venous reflux determination, the StethoDop is a valid screening instrument for venous insufficiency. However, as with determination with the classic Doppler, the reflux assessment by StethoDop gives no information about the deep veins and may miss up to 24% of apparent reflux.

Both body and arm position significantly influence blood pressure measurement.

The position of both the body and the arm during indirect blood pressure (BP) measurement is often neglected. The aim of the present study was to test the influence of the position of the patient on BP readings: (1) sitting with the arms supported precisely at the right atrium level and (2) supine: (a) with the arms precisely at the right atrium level and (b) with the arms on the examination bed. In a first group of 57 hypertensive patients, two sessions of BP and heart rate (HR) measurements were performed in two positions: sitting and supine with the arms supported precisely at right atrium level in both positions. BP was measured simultaneously at both arms, with a Hawksley Random Zero sphygmomanometer at the right arm, and with an automated oscillometric device (Bosomat) at the left arm. BP and HR readings obtained in the two positions were then compared. In a second group of 25 normo- and hypertensive persons, two sessions of BP and HR readings were performed in supine with the arms in two different arm positions: (a) the arm placed precisely at right atrium level and (b) the other arm on the examination bed. The measurements were performed at both arms with two automated devices (Bosomat). The readings taken in the two positions were compared. Both systolic BP (SBP; by 9.5 +/- 9.0 (standard deviation, s.d.); right arm) and diastolic BP (DBP; by 4.8 +/- 6.0 mmHg; right arm) were significantly higher in the supine than in the sitting position. When the two different arm positions (body continously supine) were compared in the second part of the study, significantly higher SBP (by 4.6 +/- 6.1 mmHg) and DBP (by 3.9 +/- 2.8 mmHg) were obtained when the arm of the patient was placed on the bed (below the right atrium level), than when the arm was placed at the level of the right atrium. BP readings in sitting and supine positions are not the same. When according to guidelines the arm of the patient is meticulously placed at the right atrium level in both positions, the difference is even greater than when the arm rests on the desk or on the arm support of the chair. Moreover, in the supine position small but significant differences in BP are measured between arm on a 5 cm-high pillow and arm on the bed. In every study reporting BP values, the position of both the body and especially the arm should be precisely mentioned.

Home versus Office blood pressure MEasurements: Reduction of Unnecessary treatment Study: rationale and study design of the HOMERUS trial.

The Home versus Office MEasurements, Reduction of Unnecessary treatment Study (HOMERUS) is a multicentre prospective study, primarily designed to examine in subjects with mild to moderate hypertension whether treatment decisions based on home blood pressure measurements can lead to reduction in the use of antihypertensive drugs and the associated costs, compared to office blood pressure measurements. After inclusion, 360 patients are randomized to two groups. In one group, antihypertensive therapy is based on blood pressure measured in the outpatient clinic: the office pressure (OP) group. In the other group, antihypertensive therapy is based on home blood pressure measurements: the self-pressure (SP) group. All readings, both in OP and in SP, are obtained with the same validated oscillometric device, the Omron 705 CP. Treatment decisions are taken by an independent physician at the coordinating centre, who is unaware whether the patient belongs to the SP or OP group. Following a standardized treatment schedule, blood pressure is targeted at 120-139 mmHg for systolic and 80-89 mmHg for diastolic pressure. Patients are followed for 1 year. At the start and at the end of the study, ambulatory blood pressure measurements are obtained as a reference. Microalbuminuria and echocardiography are assessed to evaluate the possible development of target organ damage. It is expected that, at the end of the trial, patients in both groups will have the same blood pressure, at the expense of more medication in the OP group. Therefore, a cost-minimization analysis will be performed first. If short-term effects appear not to be comparable for OP and SP, a cost-effectiveness analysis will be performed to assess the value of the SP strategy in comparison to standard practice. In addition, medication compliance is recorded within random subgroups of the SP and OP groups by means of Medication Event Monitoring System (MEMS) V TrackCaps.

Home blood pressure measurement with oscillometric upper-arm devices.

The market for automated blood pressure measuring devices is growing rapidly. Many patients want to buy a device for blood pressure measurement at home and ask their physician for advice about which one to choose. In this article an overview is given of the different devices available for blood pressure measurement and possible pitfalls in the interpretation of measurements taken at home are pointed out. A second article will specifically address those devices that are used to take blood pressure measurements at the wrist.

Oscillometric wrist blood pressure measuring devices.

Devices measuring blood pressure oscillometrically at the wrist are becoming more and more popular. These devices are small, easy to handle and can measure blood pressure without the need to undress. However, few of the wrist devices have been validated properly, i.e. according to internationally accepted protocols. In this article current literature on wrist blood pressure measuring devices is presented. The importance of positioning the wrist at heart level for accurate measurements is stressed.