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Brachial Artery (brachial + artery)

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Medical Sciences	93%

Distribution within Medical Sciences

Cardiovascular Disease	23%
General & Internal Medicine	18%
Diabetes	6%
Neurology	4%
11 Other Subdomains	45%

Selected Abstracts

The Effect of Angiotensin II Type-1 Receptor Gene Polymorphisms on Doppler Blood Flow Parameters of Carotid and Brachial Arteries in Patients with Myocardial Infarction

ECHOCARDIOGRAPHY, Issue 7 2006
Onder Ozturk M.D.
Background: Genetic influence on Doppler blood flow parameters of carotid and brachial arteries (BA) is uncertain. We investigated the relationship between the angiotensin II type-1 receptor (AT1R) gene polymorphism and the blood flow characteristics of common carotid arteries (CCA) and BA by color Doppler ultrasound (CDUS) in patients with a first anterior acute myocardial infarction (AMI). Methods and Results: Sixty-seven patients (15 women and 52 men), aged 25,77 years, with anterior AMI were studied. The AT1R genotypes were established. Based on the polymorphism of the AT1R, they were classified into three groups: AT1R AA genotype (Group1, n = 42 patients), AT1R AC genotype (Group 2, n = 17 patients), and AT1R CC genotype (Group 3, n = 8 patients). Peak-systolic velocity (PSV) and end-diastolic velocity (EDV) of right and left CCA, PSV of right BA, and intimal-medial thickness (IMT) of both CCA were measured by CDUS. All results evaluated statistically. The AT1R genotypes were distributed as follows: 63% AA, 25% AC, and 12% CC. PSV of BA and both CCA were higher in patients with CC and AC than AA (P < 0.05). Also, IMT of both CCA were also higher in the same groups (P < 0.05). Conclusions: Our results suggest that AT1R gene polymorphism influences Doppler blood flow parameters of both BA and CCA, and IMT of CCA. Although further studies are required. [source]

Interobserver and Intraobserver Variability of Flow-Mediated Vasodilatation of the Brachial Artery

ECHOCARDIOGRAPHY, Issue 1 2008
Iana Simova M.D.
Flow-mediated endothelial-dependent vasodilatation (FMD) of the brachial artery is a method capable of detecting endothelial dysfunction. In order to implement this method in future clinical research studies, its reproducibility and precision have to be assessed. The aim of the study is to evaluate the inter- and intraobserver variability of FMD performed in our department. We investigate 40 patients. FMD is measured by two independent observers to test the interobserver variability, and repeated by the first observer to test the intraobserver variability. We compare the baseline and post-ischemic diameter of the brachial artery and the percent dilatation. The correlation coefficients for these comparisons are high (>0.92) with a significance of less than 0.001. The inter- and intraobserver variability is further tested comparing the mean values of the baseline and post ischemic diameter of the brachial artery and the percent dilatation. The absolute values of the mean paired differences and the standard deviations (SDs) of the differences are 0.02850 ± 0.05942, P = 0.004, 0.01175 ± 0.08177, P = 0.369 and 0.28375 ± 1.61561, P = 0.273, respectively for the interobserver variability and 0.00475 ± 0.04663, P = 0.523, 0.00050 ± 0.05267, P = 0.952 and 0.15725 ± 1.19922, P = 0.412, respectively for the intraobserver variability. It can be concluded that the inter- and intraobserver variability for FMD performed in our department is acceptable. FMD can be performed precisely and accurately, with a satisfactory reproducibility and can be safely and reliably implemented in future clinical research studies. [source]

Statin therapy improves brachial artery vasodilator function in patients with Type 1 diabetes and microalbuminuria

DIABETIC MEDICINE, Issue 3 2005
G. K. Dogra
Abstract Aims Type 1 diabetes mellitus patients with microalbuminuria have endothelial dysfunction associated with the degree of albuminuria but not with LDL-cholesterol levels. Lipid-lowering agents such as statins may still be of benefit as they can correct endothelial dysfunction by both lipid and non-lipid mechanisms. We therefore examined the effects of atorvastatin on brachial artery endothelial dysfunction in these patients. Methods In a double-blind, randomized crossover study, 16 Type 1 diabetes mellitus patients with microalbuminuria received 6 weeks of atorvastatin 40 mg/day or placebo, separated by a 4-week washout. Brachial artery, endothelium-dependent, flow-mediated dilatation (FMD) and endothelium-independent, glyceryl trinitrate-mediated dilatation (GTNMD) were measured. Results Compared with placebo, atorvastatin produced a significant decrease in apolipoprotein B (34.2%), LDL-cholesterol (44.1%) (all P < 0.001), and oxidized-LDL (35.7%, P = 0.03). There was a non-significant increase in plasma cGMP (P = 0.13) on atorvastatin. FMD and GTNMD increased significantly on atorvastatin (FMD: atorvastatin +1.8 ± 0.4%; placebo +0.2 ± 0.4%, P = 0.007); (GTNMD: atorvastatin +1.3 ± 0.9%; placebo ,1.2 ± 0.6%, P = 0.04). An increase in cGMP was independently correlated with an increase in FMD on atorvastatin (adjusted R2 0.41, P = 0.02). Conclusion Atorvastatin improves endothelium-dependent and independent vasodilator function of the brachial artery in Type 1 diabetes mellitus patients with microalbuminuria. This may relate to pleiotropic effects of statins, in particular reduced oxidative stress and increased availability of nitric oxide. [source]

ENDOTHELIAL FUNCTION OF CONDUIT AND RESISTANCE ARTERIES IN NEPHROTIC RANGE PROTEINURIA

NEPHROLOGY, Issue 3 2000
G. Dogra
OBJECTIVE: To test the hypothesis that endothelial dysfunction occurs in nephrotic range proteinuria primarily as a consequence of dyslipidaemia. METHODS: Brachial artery and forearm microcirculatory endothelial function was compared among patients with nephrotic range proteinuria (NRP, n = 14 ), primary hyperlipidaemia (HL, n = 15) and normal controls (NC, n = 16). Endothelial function was studied by measuring post-ischaemic flow-mediated dilatation (FMD) of the brachial artery using high resolution ultrasonography. Endothelium-independent, glyceryl trinitrate (GTN) mediated brachial artery vasodilatation was also measured. Basal and post-ischaemic blood flow of the forearm microcirculation was measured using venous-occlusion strain gauge plethysmography. RESULTS: Serum creatinine was similar among groups. The proteinuric group had a mean albumin of 27.6g/L(1.8) and 24-hour urinary protein excretion of 6.3g(1.3). Plasma lipids and lipoproteins were not statistically different between the NRP and HL groups. Brachial artery FMD was significantly lower in the NRP and HL groups compared with the controls (NRP 4.7%(1.3)*, HL 4.9%(0.7)* and NC 8.3%(0.6), *p = 0.012 vs. NC); GTN mediated dilatation and basal and post-ischaemic forearm blood flow were not statistically different among the three groups. CONCLUSION: Patients with nephrotic range proteinuria have endothelial dysfunction of conduit arteries in the peripheral circulation, similar to that observed in patients with primary hyperlipidaemia. This suggests dyslipoproteinaemia is the principal cause of endothelial dysfunction of conduit arteries in nephrotic range proteinuria. Confirmation of this should be sought with an intervention trial of lipid-regulating therapy. [source]

Screening for atherosclerosis in patients with rheumatoid arthritis: Comparison of two in vivo tests of vascular function

ARTHRITIS & RHEUMATISM, Issue 1 2003
S. Van Doornum
Objective Inflammation appears to play a central role in atherosclerosis, and endothelial damage mediated by systemic inflammation may contribute to the increased cardiovascular mortality in rheumatoid arthritis (RA). Brachial artery flow-mediated dilatation (FMD) and pulse wave analysis (PWA) are measures of vascular function. The aim of this study was to determine if FMD and PWA are abnormal in patients with RA. Methods Twenty-five RA patients and 25 matched healthy controls were studied. All were free of traditional cardiovascular risk factors. FMD was measured in all subjects. PWA was performed in 18 RA patients and 18 controls, with results expressed as large and small artery compliance (C1 and C2). Modified Sharp scores were calculated in 13 RA patients. Results Results (mean ± SD) in RA patients and controls, respectively, were as follows: FMD 107.6 ± 4.6% versus 108.5 ± 4.1% (P = 0.49), C1 14.8 ± 2.8 ml/mm Hg × 10 versus 17.9 ± 3.1 ml/mm Hg × 10 (P = 0.0033), C2 4.5 ± 2.3 ml/mm Hg × 100 versus 7.7 ± 3.7 ml/mm Hg × 100 (P = 0.0039). There was an inverse correlation between C2 and modified Sharp scores in the RA patients (Spearman's rho ,0.69, P = 0.0085). Conclusion FMD was normal in these RA patients, whereas arterial compliance was markedly reduced. PWA appears to be a more sensitive measure of vascular dysfunction than FMD in RA and may be the preferred surrogate marker of vascular dysfunction in longitudinal studies of RA patients. The inverse correlation between C2 and the modified Sharp score, a measure that reflects disease activity over time, supports the notion that chronic inflammation plays a role in RA-associated atherosclerosis. [source]

The effects of lipid-lowering drug therapy on cardiovascular responsiveness in type 2 diabetic patients

DIABETES OBESITY & METABOLISM, Issue 1 2006
Laurence Guy HowesArticle first published online: 18 MAR 200
Type 2 diabetes is associated with a high prevalence of dyslipidaemia and a high incidence of cardiovascular disease. Lipid lowering therapy with HMG Co-A reductase inhibitors (statins) reduce the risk of cardiovascular events in type 2 diabetic and non-diabetic patients, effects which are believed to be partly due to improvements in vascular function. The aetiology of abnormal vascular function in type 2 diabetics is likely to be multifactorial and the pattern of vascular dysfunction in type 2 diabetes may differ from that which occurs in non-diabetic patients with dyslipidaemia. Abnormalities in endothelium derived hyperpolarising factor (EDHF) mediated vasodilation in resistance vessels may be more prominent in both type 1 and type 2 diabetes than in non-diabetic patients with endothelial dysfunction. The effects of lipid lowering therapy on vascular responsiveness may differ in type 2 diabetic patients from those found in non-diabetic patients. Statin therapy does not appear to improve responses to endothelial dependent vasodilators in type 2 diabetics, but may alter the ratio between nitric oxide (NO) and EDHF mediated responses. Fibrate therapy improves flow mediated dilation of brachial arteries in type 2 diabetic patients, but only appears to improve endothelium dependant vasodilator responses in resistance vessels when given in conjunction with co-enzyme Q. [source]

The Effect of Angiotensin II Type-1 Receptor Gene Polymorphisms on Doppler Blood Flow Parameters of Carotid and Brachial Arteries in Patients with Myocardial Infarction

Plasma 5-Hydroxytryptamine (5-HT) in Migraine During an Attack-Free Period

HEADACHE, Issue 4 2006
Eiichiro Nagata MD
Objective.,We measured the plasma 5-HT, 5-hydroxytryptophan (5-HTP), and tryptophan levels in controls, migraine patients with aura (MWA), and migraine patients without aura (MWoA) during an attack-free period. Background.,Serotonin (5-hydroxytryptamine, 5-HT) has been implicated in the pathophysiology of migraine. The precise relationship between 5-HT and migraine, however, remains unclear. Methods.,Blood samples in controls, MWA, and MWoA patients during an attack-free period were collected from brachial arteries and analyzed using HPLC. Results.,The plasma tryptophan and 5-HTP levels were not significantly different between the controls and migraine patients (either MWA or MWoA). However, the plasma 5-HT level in the MWA patients was significantly lower than that in the controls and MWoA patients. Conclusions.,The present data suggest that reduced levels of 5-HT in MWA may result from either a dysfunction in the enzymes involved in serotonin biosynthesis or a dysfunction in 5-HT release or uptake from platelets and lymphocytes. These findings indicate the existence of a serotonin metabolism dysfunction in MWA patients that may differ from the state of serotonin metabolism in MWoA patients. [source]

Microsurgical reconstruction of brachial artery injuries in displaced supracondylar fracture humerus in children

MICROSURGERY, Issue 7 2006
Hassan H. Noaman M.D.
Between March 2000 and March 2005, 840 children with grade III supracondylar humeral fractures presented for treatment, consecutively at our hospital. One hundred twenty had absent or diminished (detected by Doppler but not palpable) radial pulse on initial examination. Eighty-nine of these 120 children recovered pulse (palpable) after closed reduction and percutaneous pinning of the fracture. The remaining 31 children had persistent absent radial pulse. Twenty-two of the 31 children had median nerve signs. Each of these 31 children was explored. The intraoperative findings were intact median nerve in all cases (neuropraxia), traumatic aneurysm with thrombus formation in 17 cases, complete injury of the brachial artery in 8 cases (loss of continuity), thrombosis in 3 cases, partial tear in 2 cases, and brachial artery entrapment in the fracture site in 1 case. Microsurgical reconstruction of the 31 brachial arteries was done as the following: reversed vein graft for 8 cases, excision and repair in 17 cases, partial repair in 2 cases, thrombectomy in 3 cases, and release of the brachial artery from the fracture site in 1 case. The average follow up was 26 months range (6,60) months. All children had excellent to good functional and cosmetic outcome except one who had Volkman's ischemic contracture, treated later by free functioning gracilis muscle transfer. © 2006 Wiley-Liss, Inc. Microsurgery, 2006. [source]

Testing Endothelial Function of Brachial and Cavernous Arteries in Patients with Erectile Dysfunction

THE JOURNAL OF SEXUAL MEDICINE, Issue 2 2006
Evsey Mazo MD
ABSTRACT Introduction., There is considerable clinical and scientific evidence that endothelial dysfunction may be an important clinical link connecting erectile dysfunction (ED) with cardiovascular diseases. Aims., To modify the method of assessment of endothelial function of cavernosal arteries, to develop a new algorithm for evaluating its results, and to investigate the relationship between postocclusive changes in the diameter of brachial and cavernous arteries. Methods., The study participants were 212 patients presenting to our department complaining of ED and 40 healthy volunteers without sexual problems, which formed the control group. All patients with ED underwent complex evaluation and ultrasound assessment of postocclusive changes in the diameter of cavernosal arteries modified by us and standard ultrasound assessment of endothelium-dependent flow-mediated dilation of the brachial artery. Main Outcome Measures., As the main outcome measure, the percent of increase of the cavernosal arteries diameter (PICAD) was recorded. Results., In the patients with arteriogenic ED, PICAD values were significantly less than in other groups (P < 0.001 for pairs of comparison). At the same time there were no differences between the control group and groups of patients with psychogenic and organic nonarterial ED. The sensitivity and specificity of a PICAD value of 50% in diagnosis of arteriogenic ED were 100% and 98.2%, respectively. In all groups and in the entire sample of patients studied we did not find a correlation between PICAD and postocclusive changes in the diameter of brachial arteries. Conclusion., The method of ultrasound assessment of postocclusive changes in the diameter of cavernosal arteries is, reliable and, a, highly informative tool for diagnosis of arteriogenic ED. It cannot be substituted by techni-cally simpler method of ultrasound examination of brachial arteries, while results of the latter could help to define the necessity of performing an examination of cavernous arteries. Mazo E, Gamidov S, Anranovich S, and Iremashvili V. Testing endothelial function of brachial and cavernous arteries in patients with erectile dysfunction. J Sex Med 2006;3:323,330. [source]

Statin therapy improves brachial artery vasodilator function in patients with Type 1 diabetes and microalbuminuria

Association between Endothelial Function and Chronotropic Incompetence in Subjects with Chronic Heart Failure Receiving Optimal Medical Therapy

ECHOCARDIOGRAPHY, Issue 3 2010
M.D., Timothy J. Vittorio M.S.
Objective: Impairment of flow-mediated, endothelium-dependent vasodilatation (FMD) of the brachial artery identifies peripheral endothelial dysfunction in subjects with chronic congestive heart failure (CHF) and is associated with increased morbidity and mortality. To further elucidate the interaction of peripheral and central mechanisms in the syndrome of CHF, we examined the association between endothelial function and chronotropic incompetence, an emerging prognostic marker in CHF. Methods: Thirty subjects with stable New York Heart Association (NYHA) functional class II,III CHF were studied. A vascular ultrasound study was performed to measure brachial artery FMD. The percentage of age-adjusted maximal predicted heart rate (MPHR) reached during cardiopulmonary exercise tolerance testing (CPETT) was used to assess the degree of chronotropic competence. All patients received ACE inhibitors and ,-adrenoceptor blockers. Results: Brachial artery FMD averaged 1.3 ± 2.4% and age-adjusted % MPHR 74.1 ± 11.7%. FMD correlated with % MPHR among all patients (r = 0.60, P = 0.01). FMD and resting heart rate (RHR) did not significantly correlate (r = 0.13, P = 0.55). Conclusions: FMD, a measure of peripheral endothelial dysfunction, and % MPHR, a central determinant of cardiac output, are moderately correlated in heart failure patients receiving optimal medical therapy. Whether a cause-effect relationship underlies this association remains to be investigated. (Echocardiography 2010;27:294-299) [source]

The Relation between the Color M-Mode Propagation Velocity of the Descending Aorta and Coronary and Carotid Atherosclerosis and Flow-Mediated Dilatation

ECHOCARDIOGRAPHY, Issue 3 2010
Yilmaz Gunes M.D.
Background: To improve clinical outcomes, noninvasive imaging modalities have been proposed to measure and monitor atherosclerosis. Common carotid intima-media thickness (CIMT) and brachial artery flow-mediated dilatation (FMD) have correlated with coronary atherosclerosis. Recently, the color M-mode-derived propagation velocity of descending thoracic aorta (AVP) was shown to be associated with coronary artery disease (CAD). Methods: CIMT, FMD, and AVP were measured in 92 patients with CAD and 70 patients having normal coronary arteries (NCA) detected by coronary angiography. Patients with acute myocardial infarction, renal failure or hepatic failure, aneurysm of aorta, severe valvular heart disease, left ventricular ejection fraction <40%, atrial fibrillation, frequent premature beats, left bundle branch block, and inadequate echocardiographic image quality were excluded. Results: Compared to patients with normal coronary arteries, patients having CAD had significantly lower AVP (29.9 ± 8.1 vs. 47.5 ± 16.8 cm/sec, P < 0.001) and FMD (5.3 ± 1.9 vs. 11.4 ± 5.8%, P < 0.001) and higher CIMT (0.94 ± 0.05 vs. 0.83 ± 0.14 mm, P < 0.001) measurements. There were significant correlations between AVP and CIMT (r =,0.691, P < 0.001), AVP and FMD (r = 0.514, P < 0.001) and FMD and CIMT (r =,0.530, P < 0.001). Conclusions: The transthoracic echocardiographic determination of the color M-mode propagation velocity of the descending aorta is a simple practical method and correlates well with the presence of carotid and coronary atherosclerosis and brachial endothelial function. (Echocardiography 2010;27:300-305) [source]

Interobserver and Intraobserver Variability of Flow-Mediated Vasodilatation of the Brachial Artery

Evaluation of Peripheral Vascular Endothelial Function with a Portable Ultrasound Device

ECHOCARDIOGRAPHY, Issue 8 2006
Alawi A. Alsheikh-Ali M.D.
Endothelial function can be assessed noninvasively by imaging the brachial artery with ultrasound before and during reactive hyperemia. However, the standard ultrasound equipment typically used for this purpose is limited by size and expense of the machinery. In this study, we compared the ability of a portable ultrasound device to standard ultrasound equipment to visualize the brachial artery for purposes of assessing peripheral vascular endothelial function. The portable device provided comparable imaging of the brachial artery at rest and during hyperemia to that of standard ultrasound technology. These findings support the feasibility of noninvasive evaluation of peripheral endothelial function in the ambulatory setting. [source]

CD31+/Annexin V+ microparticles in healthy offsprings of patients with coronary artery disease

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 1 2009
D. Bulut
ABSTRACT Background, First-degree relatives of patients with premature coronary artery disease (CAD) develop endothelial dysfunction even in the case they are apparently healthy. In this study we wanted to clarify whether reduced blood levels of circulating endothelial progenitor cells (EPCs), an endogenous repair mechanism to replace dysfunctional endothelium, or elevated endothelial-derived microparticles (EMPs), an indicator and a mediator of increased endothelial cell damage/apoptosis, are an initial step in the pathogenesis of endothelial dysfunction in genetically predisposed subjects. Materials and methods, Fifty-six healthy young men (aged 23 to 31 years) from a fire brigade were enrolled, of which 20 subjects had a positive family history (FH) for premature CAD. Subjects with or without a positive FH did not differ with respect to age, body mass index, risk factors and C-reactive protein. Endothelial function was assessed by hyperaemia-mediated relaxation of the brachial artery, blood levels of EPCs (VEGFR2+CD34+ cells) and number of EMPs (CD31+(bright)/Annexin V+ particles) were analysed by flow cytometry. Results, Hyperaemia-mediated relaxation of the brachial artery was similar in both groups, and the blood levels of EPCs were comparable. However, the number of EMPs were significantly increased in subjects with a positive FH compared to those with a negative FH (neg. FH: 55·31 ± 4·88 vs. pos. FH: 70·37 ± 6·32 particles µL,1 platelet poor plasma; P < 0·05). Number of EMPs correlate inversely with the FMD response. Conclusions, These results suggest that increased plasma levels of EMPs may be an initial step in the development of endothelial dysfunction in genetically predisposed subjects. [source]

Atorvastatin therapy improves exercise oxygen uptake kinetics in post-myocardial infarction patients

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 6 2007
M. Guazzi
Abstract Background Statins represent a modern mainstay of the drug treatment of coronary artery disease and acute coronary syndromes. Reduced aerobic work performance and slowed VO2 kinetics are established features of the clinical picture of post-myocardial infarction (MI) patients. We tested the hypothesis that statin therapy improves VO2 exercise performance in normocholesterolaemic post-MI patients. Materials and methods, According to a double-blinded, randomized, crossover and placebo-controlled study design, in 18 patients with uncomplicated recent (3 days) MI we investigated the effects of atorvastatin (20 mg day,1) on gas exchange kinetics by calculating VO2 effective time constant (tau) during a 50-watt constant workload exercise, brachial artery flow-mediated dilatation (FMD) as an index of endothelial function, left ventricular function (echocardiography) and C-reactive protein (CRP, as an index of inflammation). Atorvastatin or placebo was given for 3 months each. Results, Atorvastatin therapy significantly improved exercise VO2 tau and FMD, and reduced CRP levels. We did not observe changes in cardiac contractile function and relaxation properties during all study periods in either group. Conclusions, In post-MI patients exercise performance is a potential additional target of benefits related to statin therapy. Endothelial function improvement is very likely implicated in this newly described therapeutic property. [source]

Endothelial dysfunction in Buerger's disease and its relation to markers of inflammation

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 6 2006
M. Joras
Abstract Background, Buerger's disease (BD) is a segmental occlusive vascular disease. The aim of this study was to detect functional changes in brachial artery and asymptomatic morphological changes in extra-cranial carotid arteries not affected by the disease process and to assess markers of inflammation and endothelial damage. Materials and methods, Fourteen patients in the remission phase of BD and the same number of age- and sex-matched healthy controls were included in the study. The capability of endothelium-dependent (flow-mediated) and endothelium-independent dilation of the brachial artery and intima-media thickness of the carotid arteries were measured using high-resolution ultrasound. Laboratory parameters of endogenous fibrinolytic activity, inflammation and endothelial dysfunction were also measured. Results, Patients with BD had a diminished capability of endothelium-dependent vasodilation and higher levels of some circulating markers of inflammation, such as leukocytes, C-reactive protein, intercellular adhesion molecule-1 and E-selectin. Intercellular adhesion molecule-1 levels were related to some of the inflammatory markers (sedimentation rate, C-reactive protein, ,2-globulins and fibrinogen), while E-selectin was correlated with decreased endogenous blood fibrinolytic activity. Endothelium-dependent vasodilation was in negative correlation with the relative share of neutrophil granulocytes. There were no significant differences in intima-media thickness between patients with BD and controls. Conclusions, Our study has expressed generalized functional arterial disorder in patients with BD not accompanied by any measurable morphological changes of the carotid arterial wall. Functional deterioration of brachial artery could be related to increased levels of various inflammatory markers , the process which is most probably the basic pathogenetic mechanism of the disease. [source]

Comparison of in vivo effects of nitroglycerin and insulin on the aortic pressure waveform

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 1 2004
J. Westerbacka
Abstract Background, Individuals whose platelets are resistant to the antiaggregatory effects of insulin in vitro are also resistant to the antiaggregatory effects of nitroglycerin (GTN). We have previously shown that insulin acutely diminishes central wave reflection in large arteries and that this action of insulin is blunted in insulin-resistant subjects. However, as yet, no studies have compared the haemodynamic effects of insulin and GTN on large arterial function in the same group of subjects. The aim of this study was to determine whether resistance to the haemodynamic effects of insulin is a defect specific to insulin or whether individuals resistant to the vascular actions of insulin are also resistant to GTN. Design and results, Dose,response characteristics of insulin and GTN on the aortic waveform were determined using applanation tonometry and pulse wave analysis (PWA) in seven healthy men (age 26 ± 1 year, BMI 25 ± 2 kg m,2). Three doses of sublingual GTN (500 µg for 1, 3 or 5 min) and insulin (0·5, 1 or 2 mU kg,1 min,1 for 120 min) were administered on three separate occasions. Both agents dose-dependently decreased central pulse pressure and the augmentation index (AIx) without changing brachial artery blood pressure. We next compared responses to insulin (2 mU kg,1 min,1 for 120 min) and sublingual GTN (500 µg for 5 min) in 20 nondiabetic subjects (age 50 ± 2 year, BMI 21·0,36·3 kg m,2). Again, both agents significantly decreased AIx. Although the vascular effects of insulin and GTN vascular were positively correlated [Spearman's r = 0·92 (95% confidence interval 0·81,0·97), P < 0·0001], the time-course for the action GTN was faster than that of insulin. Brachial systolic blood pressure remained unchanged during the insulin infusion (122 ± 3 vs. 121 ± 3 mmHg, 0 vs. 120 min) but aortic systolic blood pressure decreased significantly by 30 min (111 ± 3 vs. 107 ± 3 mmHg, 0 vs. 30 min, P < 0·01). Similarly, GTN decreased aortic systolic blood pressure from 119 ± 4 to maximally 112 ± 3 mmHg (P < 0·001) without significantly decreasing systolic blood pressure in the brachial artery. Conclusions, The effects of insulin and GTN on large arterial haemodynamics are dose-dependent and significantly correlated. The exact mechanisms and sites of action of insulin and GTN in subjects with insulin resistance remain to be established. [source]

Short-term cortisol infusion in the brachial artery, with and without inhibiting 11,-hydroxysteroid dehydrogenase, does not alter forearm vascular resistance in normotensive and hypertensive subjects

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2002
S. H. M. Van Uum
Abstract Background Vascular tone is increased in primary hypertension, and glucocorticoids affect vascular tone. Local cortisol availability is modulated by activity of 11,-hydroxysteroid dehydrogenase (11,-HSD). As this activity may be decreased in patients with primary hypertension, vascular sensitivity to cortisol may be increased in these patients. We studied the acute effect of cortisol on forearm vascular resistance (FVR) by infusing cortisol directly into the brachial artery, both with and without inhibition of 11,-HSD, in normotensive and hypertensive subjects. Design Twenty normotensive volunteers and 20 patients with primary hypertension participated in the study. After a 10-min infusion of vehicle (glucose 5%), cortisol was infused into the brachial artery in three stepwise increasing doses (3·5, 10·5 and 35 µg per 100 mL of forearm volume), each for 10 min. Next, the participants received placebo or 500 mg glycyrrhetinic acid (GA) orally, and 150 min later the same infusion schedule was repeated. Forearm vascular resistance was measured during the last 5 min of the infused vehicle and of each dose. Arterial and forearm venous plasma samples for measurement of cortisol and cortisone were taken at the end of the infusions of glucose 5% and the highest cortisol dose. Results In both normotensive and hypertensive subjects, neither the infusion of cortisol nor the administration of GA changed FVR. Also 2 h after the cortisol infusion there remained no change in FVR in both the normotensive and hypertensive groups who received placebo. Following the infusion of the highest cortisol dose, total plasma cortisone levels in the venous plasma were decreased compared with levels in the arterial plasma (36 ± 3 and 49 ± 4 nmol L,1, respectively, P < 0·05). The protein-bound venous cortisone was 37·1 ± 4·8 nmol L,1 during the vehicle compared with 23·9 ± 3·7 nmol L,1 during the cortisol infusion (P < 0·01), whereas the free cortisone level was not altered by the cortisol infusion. Conclusions In both normotensive and hypertensive subjects, high-dose cortisol infusion both with and without 11,-HSD inhibition did not change FVR either immediately or after 2 h. We could not demonstrate in vivo 11,-HSD activity in the forearm vascular tissues. When binding of cortisone to CBG is changed, e.g. during cortisol infusion, arterio-venous changes in cortisone cannot reliably be used to assess (alterations in) local 11,-HSD activity. [source]

Endothelial dysfunction in patients with ulcerative colitis

INFLAMMATORY BOWEL DISEASES, Issue 3 2006
Dr. Orhan Kocaman MD
Abstract Background: Human intestinal microvessels from chronically inflamed ulcerative colitis (UC) show microvascular endothelial dysfunction. Whether generalized endothelial dysfunction could associate with UC has not been explored yet. Our aim was to assess the endothelial function in the patients with different UC activity and to hypothesize about the relationship of endothelial function to activity-related extraintestinal complications (AREC) of UC. Methods: Twelve patients with mild UC, 14 patients with moderate UC, 16 patients with severe UC, and 24 healthy subjects were included in the study. The activity of UC is calculated according to the Seo Index. Endothelial functions of the brachial artery were evaluated by using high-resolution vascular ultrasound. Endothelial-dependent dilatation (EDD) was assessed by establishing reactive hyperemia and endothelial-independent dilatation (EID) was determined by using sublingual isosorbide dinitrate. Results: EDD was significantly worse in patients with severe UC as compared with patients with mild UC (8.7 ± 1.6% versus 17.3 ± 5.6%, P < 0.05) and even in patients with moderate UC as compared with patients with mild UC (13.1 ± 3.2% versus 17.3 ± 5.6%, P < 0.05). EDD was not significantly worse in patients with mild UC as compared with healthy subjects (17.3 ± 5.6% versus 18.1 ± 8.1%, P > 0.05). EID was significantly worse in patients with severe UC compared with patients with moderate UC (10.5 ± 2.9% versus 13.4 ± 3.7%, P < 0.05) and even in patients with mild UC compared with healthy subjects (20 ± 6.7% versus 31.1 ± 12.6%, P < 0.05). EDD and EID were significantly worse in patients with AREC compared with patients with no AREC (9.5 ± 2.5% versus 14.9 ± 5.1%, P < 0.05; 11.6 ± 4.3% versus 16 ± 6.1%, P < 0.05, respectively). Conclusions: Increased activity of UC is associated with significant endothelial dysfunction, which may relate to the pathophysiology of AREC of UC. [source]

Effects of improved glycaemic control on endothelial function in patients with type 2 diabetes

INTERNAL MEDICINE JOURNAL, Issue 6 2001
W. Bagg
Abstract Background: Patients with type 2 diabetes have abnormal endothelial function but it is not certain whether improvements in glycaemic control will improve endothelial function. Aims: To examine the effects of short-term improved glycaemic control on endothelial function in patients with inadequately regulated type 2 diabetes mellitus. Methods: Forty-three patients with type 2 diabetes and glycosylated haemoglobin (HbA1c) > 8.9% were randomized to either improved glycaemic control (IC) n = 21 or usual glycaemic control (UC) n = 22 for 20 weeks. Using high-resolution B-mode ultrasound, brachial artery flow-mediated dilatation (FMD) and glyceryl trinitrate-mediated dilatation (GTN-D) were measured at baseline and 20 weeks later. Results: After 20 weeks, HbA1c was significantly lower in IC versus UC (IC 8.02 ± 0.25% versus UC 10.23 ± 0.23%, P < 0.0001) but changes in FMD and GTN-D were not different between the groups (FMD at baseline and week 20 IC 5.1 ± 0.56% versus 4.9 ± 0.56% and UC 4.2 ± 0.51% versus 3.1 ± 0.51%; P = 0.23: GTN-D IC 12.8 ± 1.34% versus 10.4 ± 1.32% and UC 13.7 ± 1.2% versus 12.7 ± 1.23%; P = 0.39). In the IC group weight increased by 3.2 ± 0.8 kg after 20 weeks compared to 0.02 ± 0.70 kg in UC (P = 0.003). Blood pressure and serum lipid concentrations did not change in either group. Conclusions: Short-term reduction of HbA1c levels did not appear to affect endothelial function in patients with type 2 diabetes and previously poorly regulated glycaemic control. (Intern Med J 2001; 31: 322,328) [source]

Paradoxical Vasodilation During Lower Body Negative Pressure in Patients with Vasodepressor Carotid Sinus Syndrome

JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 6 2003
Arduino A. Mangoni MD
OBJECTIVES: To elucidate the pathophysiological mechanism of the vasodepressor form (VD) of carotid sinus syndrome (CSS) by maneuvers designed to induce generalized sympathetic activation after baroreceptor unloading (lower body negative pressure, LBNP) or direct peripheral adrenoreceptor stimulation via local administration of norepinephrine (NA). DESIGN: Subjects were identified with VD of CSS through diagnostic testing. SETTING: Research laboratory. PARTICIPANTS: Eleven young controls (YC) (mean age ± standard error of mean = 22.8 ± 0.7), eight elderly controls (EC) (72.6 ± 0.6), and eight elderly patients with VD (78.7 ± 1.7). MEASUREMENTS: Forearm arterial blood flow (FABF) was measured in the left and right arms by venous occlusion plethysmography. Measurements were performed during baseline conditions, LBNP (,20 mmHg), and intra-arterial NA infusion in the left brachial artery at three progressively increasing rates (60, 120, and 240 pmol/min). RESULTS: During LBNP, FABF significantly decreased in YC (baseline 3.61 ± 0.30 vs ,20 mmHg 2.96 ± 0.24 mL/100 g/min, P = .030) and EC (4.05 ± 0.74 vs 3.69 ± 0.65 mL/100 g/min, P = .033) but increased in elderly patients with VD (3.65 ± 0.60 vs 4.54 ± 0.80 mL/100 g/min, P = .020). During NA infusion, a significant forearm vasoconstriction occurred in YC (FABF left:right ratio 1.00 ± 0.05 at baseline; 0.81 ± 0.08 at 60 pmol/min, P = .034; 0.81 ± 0.05 at 120 pmol/min, P < .001; 0.72 ± 0.04 at 240 pmol/min, P < .001), whereas no significant FABF changes were observed in EC (1.04 ± 0.06; 0.96 ± 0.07, P = .655; 0.89 ± 0.10, P = .401; 0.94 ± 0.10, P = .590) or elderly patients with VD (1.04 ± 0.06; 1.16 ±0 .10, P = .117; 1.04 ± 0.08, P = .602; 1.11 ± 0.10, P = .305). CONCLUSION: VD of CSS is associated with a paradoxical vasodilatation during LBNP and an impairment of peripheral ,-adrenergic responsiveness, which may be age-related. [source]

Coarctation of the Aorta: A Secondary Cause of Hypertension

JOURNAL OF CLINICAL HYPERTENSION, Issue 6 2004
L. Michael Prisant MD
Coarctation of the aorta is a constriction of the aorta located near the ligamentum arteriosum and the origins of the left subclavian artery. This condition may be associated with other congenital disease. The mean age of death for persons with this condition is 34 years if untreated, and is usually due to heart failure, aortic dissection or rupture, endocarditis, endarteritis, cerebral hemorrhage, ischemic heart disease, or concomitant aortic valve disease in uncomplicated cases. Symptoms may not be present in adults. Diminished and delayed pulses in the right femoral artery compared with the right radial or brachial artery are an important clue to the presence of a coarctation of the aorta, as are the presence of a systolic murmur over the anterior chest, bruits over the back, and visible notching of the posterior ribs on a chest x-ray. In many cases a diagnosis can be made with these findings. Two-dimensional echocardiography with Doppler interrogation is used to confirm the diagnosis. Surgical repair and percutaneous intervention are used to repair the coarctation; however, hypertension may not abate. Because late complications including recoarctation, hypertension, aortic aneurysm formation and rupture, sudden death, ischemic heart disease, heart failure, and cerebrovascular accidents may occur, careful follow-up is required. [source]

Raloxifene, conjugated oestrogen and endothelial function in postmenopausal women

JOURNAL OF INTERNAL MEDICINE, Issue 1 2003
E. J. J. Duschek
Abstract., Duschek EJJ, Stehouwer CDA, de Valk-de Roo GW, Schalkwijk CG, Lambert J, Netelenbos C (VU University Medical Center, Amsterdam; Sophia Hospital, Zwolle; The Netherlands). Raloxifene, conjugated oestrogen and endothelial function in postmenopausal women. J Intern Med 2003; 254: 85,94. Objectives., To study the long-term effects of raloxifene, a potential designer oestrogen, and oestrogen monotherapy on endothelial function in healthy postmenopausal women. Design., A 2-year double-blind, randomized and placebo-controlled study in an Academic Medical Center. Fifty-six hysterectomized but otherwise healthy postmenopausal women randomly received raloxifene hydrochloride 60 mg day,1 (n = 15) or 150 mg day,1 (n = 13), conjugated equine oestrogen (CEE) 0.625 mg day,1 (n = 15), or placebo (n = 13). Main outcome measures., Endothelial function as estimated from brachial artery flow-mediated, endothelium-dependent vasodilation and nitroglycerine-induced endothelium-independent vasodilation, and plasma levels of the endothelium-derived regulatory proteins, von Willebrand factor (vWF) and endothelin (ET). Results., Raloxifene 60 mg did not significantly affect endothelial function. As compared with placebo, at 6 months of therapy, raloxifene 150 mg and CEE were associated with a mean increase in vWF of 25.5% point (95% CI 3.6,47.3) and 26.6% point (95% CI 6.9,46.3), respectively. At 24 months of therapy, raloxifene 150 mg was associated with a mean decrease in ET of 0.96 pg mL,1 (95% CI ,1.57 to ,0.36). Raloxifene nor CEE significantly affected endothelium-dependent and/or -independent vasodilation. Conclusions., Our results suggest that long-term therapy with raloxifene or oral CEE does not affect endothelium-dependent vasodilation in healthy postmenopausal women. Raloxifene 150 mg day,1 might have both positive and negative effects on endothelium. The clinical significance of these findings remains to be investigated. [source]

Real-Time Contrast Imaging: A New Method to Monitor Capillary Recruitment in Human Forearm Skeletal Muscle

MICROCIRCULATION, Issue 3 2008
Alexandra H. Mulder
ABSTRACT Objective: Muscle capillary perfusion can be measured by contrast-enhanced ultrasound. We examined whether a less time-consuming ultrasound technique, called "real-time imaging," could be used to measure capillary recruitment in human forearm skeletal muscle. Methods: We measured microvascular blood volume and microvascular flow velocity using bolus injections of contrast microbubbles after forearm muscle exercise and a two-hour infusion of insulin into the brachial artery (both associated with capillary recruitment) and after sodium nitroprusside infusion (no changes in flow distribution). Results: After an intravenous bolus injection of the contrast agent, the steady-state concentration of contrast agent in forearm muscle lasted long enough (approximately 190 seconds) for the duration of the measurements (which take 70,80 seconds), rendering the continuous infusion of microbubbles unnecessary. Microvascular blood-volume measurements showed a good short-time reproducibility and a good reproducibility after repositioning of the forearm. Reproducibility of microvascular flow velocity was too low. Exercise and insulin infusion both increased microvascular blood volume, consistent with capillary recruitment. Sodium nitroprusside had no effect. Conclusion: Real-time contrast imaging, after bolus injections of an ultrasound contrast agent, provides reliable information about capillary recruitment in human forearm skeletal muscle, and may offer a valuable tool in studying human (patho)physiology. [source]

Microsurgical reconstruction of brachial artery injuries in displaced supracondylar fracture humerus in children

ENDOTHELIAL FUNCTION OF CONDUIT AND RESISTANCE ARTERIES IN NEPHROTIC RANGE PROTEINURIA

Is Helicobacter pylori related to endothelial dysfunction during childhood?

PEDIATRICS INTERNATIONAL, Issue 2 2008
Senol Coskun
Abstract Background: Helicobacter pylori infection has been proposed to have a role in the development of atherosclerosis preceded by endothelial dysfunction. The aim of the present study was to determine if a relationship exists between H. pylori infection in childhood and endothelial dysfunction and level of high-sensitivity C-reactive protein (hsCRP). Methods: Between October 2003 and November 2004, 28 subjects who were anti- H. pylori IgG-positive and 25 who were anti- H. pylori IgG-negative were included in the study. Mean ages of the H. pylori -positive and negative groups were not significantly different. Endothelial functions were evaluated on Doppler ultrasonography of the brachial artery. Percent ratio of the change in systolic diameter during hyperemic phase to the basal diameter was evaluated. Each subject's serum was tested for hsCRP, homocysteine and lipids. Results: Percent ratio of the change in systolic diameters during hyperemic phase to the basal diameter was not significantly different between the H. pylori -negative and -positive groups (P > 0.29). Mean levels of hsCRP were also not significantly different (1.48 ± 1.8 g/dL vs 2.35 ± 3.33 g/dL; P > 0.24). Similarly, serum levels of lipids and homocysteine were not significantly different (P > 0.05 for all lipids). Conclusions: Non-invasive techniques used in the present study were not indicative of early findings of atherosclerosis in H. pylori infection during childhood. Further studies are required to evaluate the relationship between early endothelial dysfunction and H. pylori infection in children with cardiovascular risk factors. [source]