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Hyperemia
Kinds of Hyperemia Selected AbstractsAltered coronary vasomotor function in young patients with systemic lupus erythematosusARTHRITIS & RHEUMATISM, Issue 6 2007Kumiko Hirata Objective Accelerated atherosclerosis is an important cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Altered coronary microvascular function may act as a marker of changes that predispose to the development of significant coronary vascular disease. The purpose of this study was to compare coronary flow reserve (CFR) in a group of premenopausal women with SLE and a group of age-, sex-, and race-matched healthy control subjects. Methods Coronary flow velocity in 18 premenopausal women with SLE (mean ± SD age 29.4 ± 5.9 years) and 19 matched healthy controls (mean ± SD age 28.2 ± 4.3 years) was assessed by transthoracic Doppler echocardiography after an overnight fast. The CFR was calculated as the ratio of hyperemic to baseline coronary blood flow velocity in the left anterior descending coronary artery. Hyperemia was induced by intravenous administration of adenosine triphosphate. Results The mean ± SD duration of SLE was 8.2 ± 7.2 years (range 0.25,25 years), and the mean ± SD score on the Systemic Lupus Erythematosus Disease Activity Index was 11.0 ± 5.3 (range 4.0,21.0). Adequate recordings of flow velocity in the left anterior descending artery under both conditions were obtained using an ultrasound procedure in all study subjects. CFR was significantly lower in SLE patients as compared with control subjects (mean ± SD 3.4 ± 0.8 versus 4.5 ± 0.5; P < 0.0001). Conclusion These findings provide evidence that coronary vasomotor function is impaired in patients with SLE and support the notion that many of these young patients have subclinical coronary artery disease. [source] Bimatoprost: Mechanism of Ocular Surface Hyperemia Associated with Topical TherapyCARDIOVASCULAR THERAPEUTICS, Issue 3 2005June Chen ABSTRACT Bimatoprost is a safe and well-tolerated intraocular pressure (IOP) lowering drug that was approved in the United States in 2001 for the treatment of glaucoma and ocular hypertension. It is highly efficacious and produces greater mean reductions in IOP than other currently available antiglaucoma drugs. Conjunctival hyperemia is a common side effect of bimatoprost, but the hyperemia is typically mild and transient. No association has been found between signs of inflammation and the presence of hyperemia in bimatoprost-treated patients. Preclinical studies have elucidated the pharmacological mechanism of bimatoprost-related hyperemia and have examined the possible involvement of inflammation. Bimatoprost, as well as the free acid of latanoprost, elicited endothelium-de-pendent vasorelaxation in the rabbit jugular vein preparation, a quantitative in vitro model for ocular surface hyperemia (OSH). The vasorelaxant responses to either bimatoprost or latanoprost free acid were significantly inhibited by L-NAME, a nitric oxide synthase inhibitor. Similarly, the in vivo OSH responses to topically applied bimatoprost or latanoprost in dog eyes were significantly inhibited by L-NAME. As predicted, prostaglandin E2 (PGE2)-induced conjunctival hyperemia was not inhibited by L-NAME, since PGE2 has a direct relaxant effect on the vascular smooth muscle. In-life observations and histopatho-logical assessment of ocular surface tissues following bimatoprost treatment were performed for multiple-dose one month, 6 month, or 12 month safety studies in rabbits, dogs, and non-human primates. Results of these studies showed no evidence of bimatoprost-re-lated inflammation in the ocular surface tissues. In summary, OSH related to bimatoprost treatment in laboratory animals occurs by endothelial-derived nitric oxide-mediated vasodilatation and is not associated with inflammation. These studies suggest that conjunctival hyperemia, a side effect of bimatoprost treatment, results from non-inflammatory, pharmacologically based vasodilatation. [source] Usefulness of translesional pressure gradient and pharmacological provocation for the assessment of intermediate renal artery diseaseCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2006Noah J. Jones MD Abstract Objective: We sought to determine the hemodynamic significance of intermediate RAS by measuring translesional systolic pressure gradients (TSPG), using a pressure-sensing guidewire at baseline and after acetylcholine (ACh) induced hyperemia, following selective renal artery angiography. Background: Renal artery stenosis (RAS) is a cause of reversible hypertension and nephropathy. Stenting effectively relieves RAS, however improvement in blood pressure control or renal function is variable and unpredictable. Hemodynamic significance is usually present with RAS when diameter stenosis is >75%, but is less predictable in intermediate (30%,75%) RAS. Methods: Twenty-two patients (26 renal arteries) with uncontrolled hypertension underwent invasive hemodynamic assessment because of intermediate RAS, defined as radiocontrast angiographic diameter stenosis (DS) between 30% and 75% (quantitative DS was measured prospectively). Translesional pressure gradients were measured using a 0.014" pressure-sensing wire. Hyperemia was induced by administration of intrarenal ACh. Results: Visual and measured angiographic lesion severity did not correlate with TSPG either at baseline (visual DS, R2 = 0.091, P = 0.13; measured DS, R2 = 0.124, P = 0.07) or with hyperemia (visual DS, R2 = 0.057, P = 0.24; measured DS, R2 = 0.101, P = 0.12). Baseline and maximal hyperemic gradient did correlate (R2 = 0.567; P < 0.05). Pharmacological provocation produced a significant increase in TSPG (mean; baseline, 18 ± 21 vs. hyperemia, 34 ± 41 mm Hg; P < 0.05). A hemodynamically significant lesion (TSPG > 20 mm Hg) was found in 14/26 (54%) arteries (13 patients); 13 (60%) patients subsequently underwent renal artery stenting for hemodynamically significant RAS. At follow-up (at least 30 days), there was a significant decrease in systolic blood pressure (mean; 167 ± 24 vs. 134 ± 19 mm Hg; P < 0.001). Conclusions: Intrarenal administration of ACh induces hyperemia and can be used to unmask resistive renal artery lesions. Gradient measurement and induced hyperemia may be warranted in the invasive assessment of intermediate renal artery stenoses, rather than relying on stenosis severity alone. Further study is needed to determine whether translesional pressure gradients and pharmacological provocation predict clinical benefit after renal artery stenting. © 2006 Wiley-Liss, Inc. [source] Effect of Chronic Sustained-Release Dipyridamole on Myocardial Blood Flow and Left Ventricular Function in Patients With Ischemic CardiomyopathyCONGESTIVE HEART FAILURE, Issue 3 2007Mateen Akhtar MD Dipyridamole increases adenosine levels and augments coronary collateralization in patients with coronary ischemia. This pilot study tested whether a 6-month course of sustained-release dipyridamole/aspirin improves coronary flow reserve and left ventricular systolic function in patients with ischemic cardiomyopathy. Six outpatients with coronary artery disease and left ventricular ejection fraction (LVEF) <40% were treated with sustained-release dipyridamole 200 mg/aspirin 25 mg twice daily for 6 months. Myocardial function and perfusion, including coronary sinus flow at rest and during intravenous dipyridamole-induced hyperemia, were measured using velocity-encoded cine magnetic resonance stress perfusion studies at baseline, 3 months, and 6 months. There was no change in heart failure or angina class at 6 months. LVEF increased by 39%±64% (31.0%±13.3% at baseline vs 38.3%±10.7% at 6 months; P=.01), hyperemic coronary sinus flow increased more than 2-fold (219.6±121.3 mL/min vs 509.4±349.3 mL/min; P=.01), and stress-induced relative myocardial perfusion increased by 35%±13% (9.4%±3.4% vs 13.9%±8.5%; P=.004). Sustained-release dipyridamole improved hyperemic myocardial blood flow and left ventricular systolic function in patients with ischemic cardiomyopathy. [source] Noninvasive Assessment of Coronary Flow Reserve in the Left Anterior Descending Artery by Transthoracic Echocardiography before and after StentingECHOCARDIOGRAPHY, Issue 8 2007Elie Chammas M.D., F.E.S.C. Background: Noninvasive assessment of coronary flow reserve in the left anterior descending artery (LAD) by transthoracic Doppler echocardiography (TTDE) has been already validated as a new method for determining the degree of stenosis over the proximal flow. Objectives: The aim of the study is to determine, by TTDE, the feasibility and the value of the coronary flow reserve (CFR) (defined as the maximal increase in coronary blood flow above its basal pressure for a given perfusion pressure when coronary circulation is maximally dilated) in the mid-to-distal LAD before and after percutaneous angioplasty and to demonstrate the early recovery of microvascular tone immediately after stenting. Methods: The study population consisted of 36 patients with significant isolated LAD stenosis (70,90%) identified by coronary angiography. CFR was recorded in the mid-to-distal LAD at rest and during hyperemia obtained after adenosine intravenous infusion before and after stenting. Results: Adequate visualization of the LAD was obtained in 25 out of 36 patients (70%). At rest the mean CFR was 1.5132 ± 0.33 (1.1,2.58). However, after stenting the mean CFR was significantly higher: 2.18 ± 0.55 (1.3,3.8), with P <0.01. Conclusions: CFR can be easily determined by TTE in approximately 70% of patients. Noninvasive Doppler echocardiography shows impaired CFR in patients with LAD disease. After stenting CFR is restored, demonstrating early recovery of microvascular tone. These results are comparable to those published in the same conditions. Larger series with a long-term follow-up may allow identifying patients at high risk for restenosis after stenting. [source] Evaluation of Peripheral Vascular Endothelial Function with a Portable Ultrasound DeviceECHOCARDIOGRAPHY, Issue 8 2006Alawi 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] Noninvasive Coronary Flow Velocity Reserve Measurement in the Posterior Descending Coronary Artery for Detecting Coronary Stenosis in the Right Coronary Artery Using Contrast-Enhanced Transthoracic Doppler EchocardiographyECHOCARDIOGRAPHY, Issue 3 2004Hiroyuki Watanabe M.D. Background: Coronary flow velocity reserve (CFVR) measurement by transthoracic Doppler echocardiography (TTDE) has been found to be useful for assessing left anterior descending coronary artery (LAD) stenosis. However, this method has been restricted only for the LAD. The purpose of this study was to detect severe right coronary artery (RCA) stenosis by CFVR measurement using contrast-enhanced TTDE. Methods: In 60 consecutive patients with angina pectoris (mean (SD) age: 60 (11), 18 women), coronary flow velocities in the RCA were recorded in the postero-descending coronary artery by contrast-enhanced TTDE at rest and during hyperemia induced by intravenous infusion of adenosine triphosphate (140 mcg/ml/kg). CFVR was calculated as the ratio of hyperemic to basal peak and mean diastolic flow velocity. CFVR measurements by TTDE were compared with the results of coronary angiography performed within 1 week. Results: Coronary flow velocity was successfully recorded in 49 (82%) of the 60 patients with contrast agent. CFVR (mean (SD)) was 1.4 (0.4) in patients with, and 2.6 (0.6) in patients without significant stenosis in the RCA (%diameter stenosis > 75%, P < 0.001). Using the cutoff value 2.0 for CFVR in the RCA, its sensitivity and specificity in detecting significant stenosis in the RCA were 88% and 91%, respectively. Conclusion: CFVR measurement in the postero-descending coronary artery by contrast enhanced TTDE is a new, noninvasive method to detect significant stenosis in the RCA. (ECHOCARDIOGRAPHY, Volume 21, April 2004) [source] Noninvasive Assessment of Significant Right Coronary Artery Stenosis Based on Coronary Flow Velocity Reserve in the Right Coronary Artery by Transthoracic Doppler EchocardiographyECHOCARDIOGRAPHY, Issue 6 2003M.D., Yoshiki Ueno Background: Coronary flow velocity reserve (CFVR) measured by transthoracic Doppler echocardiography (TTDE) has been reported to be useful for the noninvasive assessment of coronary stenosis in the left anterior descending artery. However, the measurement of CFVR in the right coronary artery by TTDE has not yet been validated in a clinical study. Objective: The aim of this study was to evaluate whether CFVR by TTDE can detect significant stenosis in the right coronary artery. Methods: We studied 50 patients who underwent coronary angiography. Coronary flow velocity in the posterior descending branch of the right coronary artery (PD) was measured by TTDE both at baseline and during hyperemia induced by the intravenous infusion of adenosine triphosphate. CFVR was calculated as the hyperemia/baseline (average diastolic peak velocity). Results: Adequate spectral Doppler recordings in the PD were obtained in 36 patients including 26 patients who were given an echocardiographic contrast agent to improve Doppler spectral signals. The study population was divided into 2 groups with (Group A;n = 11) and without (Group B;n = 25) significant stenosis in the right coronary artery. CFVR in Group A was significantly smaller than that in Group B (1.6±0.3versus2.5±0.4; P < 0.0001). The sensitivity of a CFVR of <2.0 for predicting the presence of significant stenosis in the right coronary artery was 91%, and the specificity was 88%. Conclusions: The measurement of CFVR in the PD by TTDE is useful for the noninvasive assessment of significant stenosis in the right coronary artery. (ECHOCARDIOGRAPHY, Volume 20, August 2003) [source] A diet enriched with mackerel (Scomber scombrus),derived products improves the endothelial function in a senior population (Prevención de las Enfermedades Cardiovasculares: Estudio Santoña , PECES project)EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 3 2009J. R. De Berrazueta ABSTRACT Background, Regular consumption of fish reduces cardiovascular risks. Here, we investigate if the consumption of products with mackerel (Scomber scombrus) with 8·82 g of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) content per 100 g of product improves parameters of endothelial function in a controlled population. Materials and methods, Subjects maintained a 12-week diet with products with mackerel. The population consisted of 58 senior subjects (12 withdrawals, 25 women), aged 82·08 ± 8·13 years (Group A). Twenty-three senior subjects (13 women) on a regular diet were used as the control group (Group B). Subjects of Group A received 57 portions throughout 12 weeks (four to five portions a week of products with a mean EPA + DHA content of 2·5 g a day). A continuous follow-up and a final evaluation were performed to determine the level of consumption. Plasma samples were stored at ,70 °C for a biochemical study. Endothelial function was analysed by reactive hyperemia with a mercury strain gauge plethysmography with measurement of blood flow in the forearm, both baseline and at the end of the 12-week diet. Results, Endothelium-dependent vasodilatation significantly increased in Group A subjects (P < 0·001). No changes were found in Group B. The subgroup analyses showed that improvements were produced in Group A subjects without cardiovascular disease (P < 0·001). Nitrites/nitrates and von Willebrand factor plasma concentrations were higher in participants after the 12-week diet. Conclusions, The consumption of mackerel meat products improves endothelium-dependent, flow-mediated vasodilatation in a senior population. This finding might explain some of the cardioprotective effects of fish consumption. [source] Clinical methods for the evaluation of endothelial function , a focus on resistance arteriesFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2006Robinson Joannides Abstract Endothelial dysfunction is a key event in the pathophysiology of cardiovascular diseases and appears as a strong independent predictor of cardiovascular events. In this context, biological evaluation of endothelial circulating markers can be helpful. However, functional tests using pharmacological stimuli appear more specific for the study of resistance arteries. These methods consist in the evaluation of the endothelium-dependent changes in regional vascular flow in response to local infusion of substances that act through endothelial receptors without modification of systemic arterial pressure and in comparison with a non endothelium-dependent relaxation. Flow is measured by Doppler and intravascular ultrasound in coronary circulation, laser Doppler in skin and by venous occlusion plethysmography in peripheral muscular arteries. Similar studies can be performed ex vivo using isolated resistance arteries obtained from fat subcutaneous biopsies. In addition, other information can be obtained from reactive hyperemia and the study of the flow-mediated dilatation of conduit arteries to enable a selective and comprehensive approach of the heterogeneity of endothelial function in pathophysiology. [source] Low doses of isosorbide mononitrate attenuate the postprandial increase in portal pressure in patients with cirrhosisHEPATOLOGY, Issue 2 2003Lia Bellis Postprandial hyperemia is associated with a significant increase in portal pressure in cirrhosis, which may contribute to progressive dilation and rupture of gastroesophageal varices. In cirrhosis, an insufficient hepatic production of nitric oxide (NO) may impair the expected hepatic vasodilatory response to increased blood flow, further exaggerating the postprandial increase in portal pressure. This study was aimed at investigating whether low doses of an oral NO donor might counteract the postprandial peak in portal pressure. Twenty-three portal hypertensive cirrhotics, 8 of them under propranolol therapy, were randomized to receive orally 5-isosorbide mononitrate (ISMN; 10 mg; n = 11) or placebo (n = 12) and a standard liquid meal 15 minutes later. Hepatic venous pressure gradient (HVPG), mean arterial pressure (MAP), and hepatic blood flow (HBF) were measured at baseline and 15, 30, and 45 minutes after a meal. ISMN significantly attenuated the postprandial increase in portal pressure as compared with placebo (peak HVPG increase: 2.4 ± 1.4 mm Hg vs. 5.2 ± 2.1 mm Hg, P = .002). Percentual increases in HBF were similar in both groups. MAP decreased slightly in ISMN group (,7.5% ± .5%; P < .01 vs. baseline). These effects were also observed in patients on chronic propranolol therapy. In conclusion, hepatic NO supplementation by low doses of ISMN effectively reduces the postprandial increase of portal pressure in cirrhosis, with only a mild effect on arterial pressure. The same was observed in patients receiving propranolol. Our results suggest that therapeutic strategies based on selective hepatic NO delivery may improve the treatment of portal hypertension. [source] Endothelial dysfunction in patients with ulcerative colitisINFLAMMATORY BOWEL DISEASES, Issue 3 2006Dr. 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] Acute febrile neutrophilic dermatosis (Sweet's syndrome) with nodular episcleritis and polyneuropathyINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 2 2002Taizo Kato MD A 56-year-old Japanese housewife presented with multiple erythematous lesions in association with ocular hyperemia and pain in the right upper and lower extremities, including the hands and feet. These symptoms were preceded by a sore throat with persistent fever higher than 38.5 °C for about 1 week. Dermatologic examination showed tender, dull-red, erythematous lesions, measuring 1,2 cm in diameter, located predominantly on the forehead, cheeks, auricular region, neck, forearm, hands, and feet. A biopsy specimen obtained from an erythematous lesion on the right forearm revealed prominent edema in the papillary dermis and remarkable inflammatory cell infiltration throughout the entire dermis (Fig. 1). The infiltrate predominantly consisted of neutrophils and nuclear dust without signs of vasculitis. In routine examination, the leukocyte count was 15,000/mL (normal range, 4000,8000/mL) with severe neutrophilia (80%). The C-reactive protein (CRP) level was 17.65 mg/dL (normal range, < 0.5 mg/dL) and the anti-streptolysin (ASLO) level was 611 IU/mL (normal range, < 166 IU/mL). In human leukocyte antigen (HLA) testing, HLA-A2, -B39, -B35, -Cw2, and -Cw7 were positive, and HLA-B51, -B54, and -Cw1 were negative. Figure Figure 1 . Histologic picture showing a dermal infiltrate of neutrophils Ocular hyperemia was caused by episcleritis forming a nodule and surrounding congestion of the superficial episcleritic vessels at the central portion of the sclera (Fig. 2). The patient suffered from pain once an hour, continuing for about 3 min, at the lateral portion of the right upper and lower extremities, as well as the right small finger. Neurologic examination demonstrated moderate or slight muscle weakness in the extremities. Hand grasping powers were 9 and 7 kg on the right and left, respectively. The patient was right-handed. Dysesthesia and paresthesia were also observed on the hands and feet. The deep tendon reflexes were preserved, however, even in the distal portion of the upper and lower limbs. In addition, essential tremor localized to the neck was recognized. Magnetic resonance imaging did not show any episodes of transient abnormal signal intensity in the central nervous system. Figure 2. Nodular episcleritis (right eye). Telangiectasia of winding vessels with nodular elevation was observed at the upper portion of the sclera The patient was treated with prednisolone (initial dose of 30 mg/day) and intravenous injection of cefazolin sodium (2 g/day for 5 days). Almost complete regression of the ocular and neurologic manifestations, as well as the skin lesions, was achieved in 2 weeks. Prednisolone was reduced gradually and suspended after 4 weeks. Leukocyte and neutrophil counts, CRP, and ASO returned to normal on suspension of therapy. Slight paresthesia remained in the right small finger even after stopping steroid. There was no recurrence at follow-up 6 months later. [source] Ineffective Peripheral Tissue Perfusion: Clinical Validation in Patients With Hypertensive CardiomiopathyINTERNATIONAL JOURNAL OF NURSING TERMINOLOGIES AND CLASSIFICATION, Issue 2 2006Rita de Cassia Gengo de Silva MS PURPOSE.,To validate defining characteristics of ineffective peripheral tissue perfusion using vasomotor function assessment. METHODS.,Twenty-four patients with hypertensive cardiomiopathy were evaluated for 18 defining characteristics of ineffective peripheral tissue perfusion and underwent vasomotor function assessment with induction of reactive hyperemia, intra-arterial infusion of acetylcholine, and pulse wave velocity measurement. The Student's t test and Kruskall,Wallis test were used to assess the significance of relationships between defining characteristics and vasomotor function data. FINDINGS.,Diminished lower extremity pulses were associated with diminished forearm blood flow during acetylcholine infusion; left ventricular overload, intermittent claudication, and diminished skin moisture were associated with elevated pulse wave velocity values. CONCLUSION.,The defining characteristics of ineffective peripheral tissue perfusion were highly associated with vasomotor function data as "gold standards" for that diagnosis. PRACTICE IMPLICATIONS.,Nurses should be able to accurately assess diminished lower extremity pulses, intermittent claudication, and diminished skin moisture as relevant characteristics of ineffective peripheral tissue perfusion in patients with hypertensive cardiomiopathy. Irrigation Tissulaire Périphérique Inefficace: Validation Clinique Chez les Patients Atteints de Cardiomyopathie Hypertensive BUT.,Valider les caractéristiques de Irrigation tissulaire périphérique inefficace en utilisant l'évaluation de la fonction vasomotrice. MÉTHODES.,Vingt-quatre patients souffrant de cardiomyopathie hypertensive furent évalués au regard des 18 caractéristiques du diagnostic Irrigation vasculaire périphérique inefficace et de la fonction vasomotrice par induction d'une hyperémie réactionnelle, la perfusion intra-artérielle d'acétylcholine, et la mesure de la vélocité de l'onde du pouls. Les tests "Student t et Kruskall,Wallis" furent utilisés pour déterminer l'importance des liens entre les caractéristiques et les valeurs de la fonction vasomotrice. RÉSULTATS.,La diminution des pulsations périphériques des membres inférieurs fut associée à une diminution du flot sanguin pendant la perfusion d'acétylcholine; une surcharge ventriculaire gauche, de la claudication intermittente et une diminution de l'hydratation de la peau furent associées à des valeurs élevées de la vélocité de l'onde du pouls. CONCLUSION.,,Les caractéristiques de Irrigation tissulaire périphérique inefficace qui furent associées de manière significative à la fonction vasomotrice peuvent être considérées comme les "étalons or" de ce diagnostic. IMPLICATIONS POUR LA PRATIQUE.,Les infirmières devraient être capables d'évaluer correctement la diminution des pouls périphériques, la claudication intermittente, et la diminution de l'hydratation de la peau, car ce sont des caractéristiques pertinentes de l'irrigation tissulaire périphérique inefficace chez les patients atteints de cardiomyopathie hypertensive. Translation by Cécile Boisvert, MSN, RN Perfusão Tissular Periférica Ineficaz: Validação Clínica em Pacientes com Miocardiopatia Hipertensiva PROPÓSITO.,Validar as caraterísticas definidoras do diagnóstico de perfusão tissular periférica ineficaz usando a avaliação da função vasomotora. MÉTODO.,Vinte e quatro pacientes com miocardiopatia hipertensiva foram avaliados segundo 18 características definidoras de perfusão tissular periférica ineficaz e submetidos a avaliação da função vasomotora por indução de hiperemia reativa, infusão intra-arterial de acetilcolina e por mensuração da velocidade da onda de pulso. Testes T de Student e de Kruskall,Wallis foram aplicados para avaliar a significância das relações entre as características definidoras e os dados da função vasomotora. RESULTADOS.,Diminuição de pulso nas extremidades inferiores foi associada com o menor fluxo de sangue no antebraço durante a infusão de acetilcolina; sobrecarga ventricular esquerda, claudicação intermitente e diminuição da hidratação da pele foram associados com valores elevados de velocidade de onda de pulso. CONCLUSÃO.,Quatro características definidoras de perfusão tissular periférica ineficaz foram altamente associadas com função vasomotora alterada como "padrão ouro" para este diagnóstico. IMPLICAÇÕES PARA A PRÁTICA.,As enfermeiras devem ser capazes de avaliar com precisão a diminuição dos pulsos das extremidades inferiores, claudicação intermitente e diminuição na hidratação da pele como características definidoras relevantes da perfusão tissular periférica ineficaz em pacientes com miocardiopatia hipertensiva. Translation by Alba Leite de Barros, PhD, RN Perfusión Tisular Periférica Inefectiva: Validación Clínica en Pacientes que Presentan Miocardiopatía Hipertensiva PROPÓSITO.,Validar las características definitorias del diagnóstico Perfusión tisular periférica inefectiva utilizando una valoración de la función vasomotora. METODOLOGÍA.,Veinticuatro pacientes diagnosticados de Miocardiopatía Hipertensiva fueron evaluados con respecto a las 18 características definitorias del diagnóstico Perfusión tisular periférica inefectiva y sometidos a una valoración de la función vasomotora con inducción de Hiperemia reactiva, infusión intra-arterial de acetilcolina, y medida de la velocidad de la onda del pulso. Se utilizaron los análisis estadísticos de t-Student y Kruskall,Wallis para valorar el significado de las relaciones entre las características definitorias y los datos obtenidos de la valoración de la función vasomotora. HALLAZGOS.,Durante la infusión de acetilcolina se detectó disminución de los pulsos en la extremidad inferior relacionado con la disminución del volumen de sangre en el antebrazo; la sobrecarga ventricular izquierda, claudicación intermitente y disminución de la hidratación de la piel fueron asociadas con la elevación de los valores de la velocidad de la onda del pulso. CONCLUSIÓN.,Las características definitorias del diagnóstico Perfusión tisular periférica inefectiva estaban fuertemente asociadas a los datos procedentes de la valoración de la función vasomotora identificándose como "estándares fundamentales" para este diagnóstico. IMPLICACIONES PARA LA PRÁCTICA.,Las enfermeras deberían ser capaces de valorar cuidadosamente la presencia de pulsos disminuidos en las extremidades inferiores, y la disminución de la hidratación de la piel ya que son características relevantes del diagnóstico Perfusión tisular periférica inefectiva en pacientes que presentan Miocardiopatía Hipertensiva. Translation by Adolf Guirao, RN [source] Association of Sjögren's syndrome and rosacea: a diagnostic challengeINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 2 2007Leopoldo Luiz Dos SANTOS-NETO Abstract Both Sjögren's syndrome and rosacea present clinical manifestations that include ocular involvement. We report a case of a 45-year-old woman with a history of persistent erythematous malar rash, associated with conjunctival hyperemia, xerophthalmia and blefaritis. The patient filled the current classification criteria proposed for Sjögren's syndrome and those for rosacea. The coexistence of these diseases has not been previously described in the literature. Both diseases have similar symptoms and different treatment approaches. We believe that it is important for clinicians to identify this association in order to provide better care for the patient. [source] New Glaucoma Medications in the Geriatric Population: Efficacy and SafetyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 5 2002Gary D. Novack PhD Glaucoma can be considered a disease of the aging eye. Most medications used to treat glaucoma are in topical eyedrop form and may cause numerous untoward systemic effects in older persons. In recent years, several new ocular hypotensive medications have become available. These medications are being used more commonly because there is a growing trend by ophthalmologists to aggressively lower intraocular pressure. Therefore, geriatricians require a comprehensive knowledge of medications used to treat glaucoma, in addition to an understanding of their mechanism of action profiles of untoward effects and possible interactions with other diseases or medications. Therefore, we performed a review of the medications recently introduced into clinical practice. We selected drugs approved by the U.S. Food and Drug Administration between 1996 and September 2001. The safety profiles of these agents and their untoward side effects were reviewed by class: topical carbonic anhydrase inhibitors (brinzolamide: ocular tolerance, taste perversion), ,-adrenoceptor antagonists (timolol: bradycardia and bronchospasm), ,-adrenergic agonists (brimonidine: oral dryness, headache, and fatigue), and prostaglandin analogs (latanoprost, bimatoprost, travoprost, and unoprostone isopropyl: ocular hyperemia, iris color changes). The function of this review is to make geriatricians more aware of the efficacy and untoward effects of medications recently introduced into clinical practice. We recommend that geriatricians perform a medication review on all medications their patients use, including eye drops. [source] Crohn's disease and color Doppler sonography: Response to treatment and its relationship with long-term prognosisJOURNAL OF CLINICAL ULTRASOUND, Issue 5 2008Tomás Ripollés Abstract Purpose To evaluate the ability of sonography to detect changes in patients undergoing treatment for Crohn's disease and whether these findings are related to the patient's long-term outcome. Methods Twenty-eight patients with Crohn's disease were examined prospectively using gray-scale and color Doppler sonography before and during treatment. Three sonographic examinations were made: on the first day of treatment, between 3 and 8 days later, and approximately 4 weeks after starting the treatment. Sonographic examination included an evaluation of maximum bowel wall thickness and vascularity pattern. The sonographic data were compared with clinical and laboratory data, and possible relation with the patient's long-term outcome was considered. Results Initial baseline sonograms revealed at least 1 thickened segment of the bowel wall in all of the patients. In this initial examination, 18 of 22 patients (81%) with clinically active disease had moderate or marked parietal vascularity. A statistically significant reduction in the vascularity of the affected bowel was observed on the third sonographic examination (p < 0.05). Seventeen patients who were in clinical remission had relapses and were treated with immunosuppressive therapy or surgery during the follow-up. Eighty-six percent of the patients with residual hyperemia on sonographic examination after treatment had an unfavorable clinical course compared with only 30% of the patients with no, or barely visible, residual hyperemia (p < 0.01). Conclusion Sonography can identify bowel inflammation and its changes during treatment. In patients with Crohn's disease, hyperemia on color Doppler sonography during clinical remission after treatment may reflect an increased risk of relapse. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2008 [source] Assessing arterial blood flow and vessel area variations using real-time zonal phase-contrast MRIJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2006Markus Oelhafen PhD Abstract Purpose To measure peripheral artery function using a real-time phase-contrast (PC)-MRI sequence with tailored image-processing algorithms for flow computation. Materials and Methods An approach to real-time flow measurements was developed based on two-dimensional spatially selective excitation pulses and consecutive tailored processing of the data to derive blood flow and vessel area variations. The data acquisition strategy allows for flow measurements at high spatial and temporal resolutions of 1 mm2 and 50 msec, respectively. In postprocessing the vessel area is automatically extracted using correlation measures in conjunction with morphological image operators. By means of in vitro and in vivo validations, it is shown that the current methods provide accurate and reproducible measurements of flow and vessel area variations. Results In vitro the comparison between the lumen area measured with the presented method and the values obtained by calliper gauge measurement showed a difference of 3.4% ± 3.4% (mean ± 2 SD). Similarly, the comparison between the stroke volumes determined with the presented method and by stopwatch and bucket measurements yielded a difference of 6.1% ± 2.1%. In vivo the results from the real-time measurements for lumen area and stroke volume were compared with those from a gated PC-MRI technique with differences of 4.8% ± 14% and 3.0% ± 24.7%, respectively. Conclusion The presented method constitutes a reliable tool set for quantifying the variations of blood flow and lumen area in the superficial femoral artery during reactive hyperemia and for studying their correlation with cardiovascular risk factors. J. Magn. Reson. Imaging 2006. © 2006 Wiley-Liss, Inc. [source] Cerebral Hemodynamics Changes During Retrograde Brain Perfusion in DogsJOURNAL OF NEUROIMAGING, Issue 2 2001Alexander Y. Razumovsky PhD ABSTRACT The objective of this study was to examine cerebral hemodynamics changes during hypothermic circulatory arrest (HCA) with and without retrograde cerebral perfusion (RCP). Thirteen colony-bred hound dogs were placed on cardiopulmonary bypass (CPB) and cooled to 18°C. Five dogs underwent 2 hours of HCA without RCP and 8 with RCP. The animals were then rewarmed on CPB until normothermic and weaned. Cerebral blood flow velocity (CBFV) and Gosling Pulsatility Index (PI) in the middle cerebral artery (MCA) were studied using transcranial Doppler (TCD) ultrasound. At baseline and during pre- and postarrest CPB, there was anterograde direction of blood flow in the MCA. During HCA with RCP, there was retrograde direction of blood flow in the MCA. There was no difference in CBFV between pre-, during, and postarrest CPB in the group with RCP; however, there was significantly increased CBFV during postarrest CPB in the group without RCP compared to the dogs with RCP. Later, at 3 hours after postarrest CPB, there was decreased CBFV in all animals accompanied by increased PI (2.4 ± 0.4 and 2.2 ± 0.6 for animals with RCP and without RCP, respectively) and abnormal TCD waveform changes including decreased diastolic compartment and sharp systolic peak. During hypothermic circulatory arrest, RCP provides CBFV in the MCA comparable to MCA CBFV during CPB. HCA dogs without RCP showed immediate hyperemia on reperfusion. The decreased CBFV and increased PI at 1 hour after postarrest CPB could be an indicator of progressive ischemic injury due to the increased intracranial pressure despite the implementation of RCP. [source] Application of intensive care medicine principles in the management of the acute liver failure patientLIVER TRANSPLANTATION, Issue S2 2008David J. Kramer Key Points 1Acute liver failure is a paradigm for multiple system organ failure that develops as a consequence of sepsis. 2In the United States, systemic inflammatory response, sepsis, and septic shock are common reasons for intensive care unit admission. Intensive care management of these patients serves as a template for the management of patients with acute liver failure. 3Acute liver failure is attended by high mortality. Although intensive care results in improved survival, the key treatment is liver transplantation. Intensive care unit intervention may open a "window of opportunity" and enable successful liver transplantation in patients who are too ill at presentation. 4Intracranial hypertension complicates the course for many patients with acute liver failure. Initially, intracranial hypertension results from hyperemia, which is cerebral edema that reduces cerebral blood flow and eventuates in herniation. The precepts of neurocritical care,monitoring cerebral perfusion pressure, cerebral blood flow, and cortical activity,with rapid response to hemodynamic abnormalities, maintenance of normoxia, euglycemia, control of seizures, therapeutic hypothermia, osmotic therapy, and judicious hyperventilation are key to reducing mortality attributable to neurologic failure. Liver Transpl 14:S85,S89, 2008. © 2008 AASLD. [source] Time Development Models for Perfusion Provocations Studied with Laser-Doppler Flowmetry, Applied to Iontophoresis and PORHMICROCIRCULATION, Issue 7 2009Frits F.M. De Mul ABSTRACT Objective: Clinical acceptance of laser-Doppler perfusion monitoring (LDPM) of microcirculation suffers from lack of quantitatively reliable signal data, due to varying tissue constitution, temperature, hydration, etc. In this article, we show that a novel approach using physiological models for response upon provocations provides quantitatively and clinically relevant time constants. Methods: We investigated this for two provocation protocols: postocclusive reactive hyperemia (PORH) and iontophoresis shots, measured with LDPM on extremities. PORH experiments were performed on patients with peripheral arterial occlusive disease (PAOD) or diabetes mellitus (DM), and on healthy controls. Iontophoresis experiments were performed on pre-eclamptic patients and healthy controls. We developed two dynamical physical models, both based on two characteristic time constants: for PORH, an "arterial" and a "capillary" time constant and, for iontophoresis, a "diffusion" and a "decay" time constant. Results: For the different subject groups, we could extract time constants that could probably be related to physiological differences. For iontophoresis, a shot saturation constant was determined, with very different values for different groups and administered drugs. Conclusions: With these models, the dynamics of the provocations can be investigated and quantitative comparisons between experiments and subject groups become available. The models offer a quantifiable standard that is independent of the type of LDPM instrumentation. [source] Hydrogen Peroxide-Dependent Arteriolar Dilation in Contracting Muscle of Rats Fed Normal and High Salt DietsMICROCIRCULATION, Issue 8 2007Paul J. Marvar ABSTRACT Objective: High dietary salt intake decreases the arteriolar dilation associated with skeletal muscle contraction. Because hydrogen peroxide (H2O2) can be released from contracting muscle fibers, this study was designed to assess the possible contribution of H2O2 to skeletal muscle functional hyperemia and its sensitivity to dietary salt. Methods: The authors investigated the effect of catalase treatment on arteriolar dilation and hyperemia in contracting spinotrapezius muscle of rats fed a normal salt (0.45%, NS) or high salt (4%, HS) diet for 4 weeks. Catalase-sensitive 2,,7,-dichlorofluorescein (DCF) fluorescence was measured as an index of H2O2 formation, and the mechanism of arteriolar dilation to H2O2 was probed in each group using pharmacological inhibitors. Results: DCF fluorescence increased with muscle contraction, but not if catalase was present. Catalase also reduced arteriolar dilation and hyperemia during contraction in both dietary groups. Exogenous H2O2 dilated arterioles in both groups, with greater responses in HS rats. Guanylate cyclase inhibition did not affect arteriolar responses to H2O2 in either group, but KCa or KATP channel inhibition equally reduced these responses, and KATP channel inhibition equally reduced functional hyperemia in both groups. Conclusions: These results indicate that locally produced H2O2 contributes to arteriolar dilation and hyperemia in contracting skeletal muscle, and that the effect of H2O2 on arteriolar tone in this vascular bed is mediated largely through K+ channel activation. High dietary salt intake does not reduce the contribution of H2O2 to active hyperemia, or alter the mechanism through which H2O2 relaxes arteriolar smooth muscle. [source] Regulation of Muscle Blood Flow in ObesityMICROCIRCULATION, Issue 4-5 2007Benjamin L. Hodnett ABSTRACT Obesity has been shown to impair muscle blood flow in humans. Vasodilatory control mechanisms such as metabolic control, myogenic mechanisms, conducted vasodilation, and release of endothelium-derived factors may be impaired in obesity due to insulin resistance, hyperglycemia, dyslipidemia, inflammation, oxidative stress, and endothelial dysfunction. The physiological importance of these blood flow control mechanisms has predominately been determined during the increase in blood flow (functional hyperemia) that occurs in response to the increased metabolism associated with exercise. This review examines the mechanisms by which functional hyperemia may be impaired in obesity and indicates areas where further studies are needed. The most extensively studied area of obesity-induced changes in muscle blood flow has been the role of endothelium-derived mediators during resting blood flow and exercise-induced hyperemia. Elevations in oxidative stress alter endothelium-derived factors, resulting in impaired vasodilatory responses. Alterations in metabolic and conducted vasodilatory regulation of blood flow have not been extensively studied in obesity, providing a potential area of research. [source] Regulation of Blood Flow in the MicrocirculationMICROCIRCULATION, Issue 1 2005STEVEN S. SEGAL ABSTRACT The regulation of blood flow has rich history of investigation and is exemplified in exercising skeletal muscle by a concerted interaction between striated muscle fibers and their microvascular supply. This review considers blood flow control in light of the regulation of capillary perfusion by and among terminal arterioles, the distribution of blood flow in arteriolar networks according to metabolic and hemodynamic feedback from active muscle fibers, and the balance between peak muscle blood flow and arterial blood pressure by sympathetic nerve activity. As metabolic demand increases, the locus of regulating oxygen delivery to muscle fibers "ascends" from terminal arterioles, through intermediate distributing arterioles, and into the proximal arterioles and feed arteries, which govern total flow into a muscle. At multiple levels, venules are positioned to provide feedback to nearby arterioles regarding the metabolic state of the tissue through the convection and production of vasodilator stimuli. Electrical signals initiated on smooth muscle and endothelial cells can travel rapidly for millimeters through cell-to-cell conduction via gap junction channels, rapidly coordinating vasodilator responses that govern the distribution and magnitude of blood flow to active muscle fibers. Sympathetic constriction of proximal arterioles and feed arteries can restrict functional hyperemia while dilation prevails in distal arterioles to promote oxygen extraction. With vasomotor tone reflecting myogenic contraction of smooth muscle cells modulated by flow-induced vasodilator production by endothelium, the initiation of functional vasodilation and its modulation by shear stress and sympathetic innervation dictate how and where blood flow is distributed in microvascular networks. A remarkable ensemble of signaling pathways underlie the integration of smooth muscle and endothelial cell function in microvascular networks. These pathways are being defined with new insight as novel approaches are applied to understanding the cellular and molecular mechanisms of blood flow control. [source] Acetylcholine-Induced Vasodilation and Reactive Hyperemia Are Not Affected by Acute Cyclo-Oxygenase Inhibition in Human SkinMICROCIRCULATION, Issue 4 2004Anne Dalle-Ave Objective: To examine whether prostaglandins are involved in endothelium-dependent vasodilatory responses of the skin microcirculation. Methods: Twenty-three young male volunteers were studied on 2 different days 1,3 weeks apart. On each experimental day the forearm skin blood flow response to iontophoretically applied acetylcholine (Ach, an endothelium-dependent vasodilator) was determined with laser Doppler imaging following the intravenous administration of either the cyclo-oxygenase inhibitor lysine acetylsalicylate (L-AS), 900 mg, or the oral intake of indomethacin, 75 mg. Acetylcholine was iontophoresed both in presence and in absence of surface anesthesia. In some subjects, the effects of L-AS on skin reactive hyperemia were also assessed. Results: Acute cyclo-oxygenase inhibition with either drug influenced neither the skin blood flow response to 4 different doses of Ach (0.28, 1.4, 7, and 14 mC/cm2) nor reactive hyperemia. The peak vasodilatory response to Ach was significantly increased by skin anesthesia, regardless of whether the subjects received the cyclo-oxygenase inhibitor or not. For example, the mean response (± SD) to the largest dose of Ach (tested in 6 subjects, expressed in perfusion units) were as follows: in absence of anesthesia: L-AS 339 ± 105, placebo 344 ± 68; with anesthesia: L-AS 453 ± 76, placebo 452 ± 65 (p < .01 for effect of anesthesia). Conclusions: These data give no support for a contribution of prostaglandins to acetylcholine-induced vasodilation or to reactive hyperemia in the skin microcirculation. In this vascular bed, local anesthesia seems to amplify acetylcholine-induced vasodilation via a prostaglandin-independent mechanism. [source] Efficacy and safety of single- and multiple-dose ketotifen fumarate 0.025% ophthalmic solution in a pediatric populationPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 6 2004Mark B. Abelson Allergic conjunctivitis can seriously disrupt children's daily activities. This study assessed the efficacy (onset and duration of action) and safety of ketotifen fumarate 0.025% ophthalmic solution compared with vehicle placebo in pediatric subjects after single and multiple dosing. This was a double-masked, multicenter, fellow-eye, placebo-controlled, conjunctival allergen challenge trial. Eligible subjects (8,16-yr-olds) who produced a qualifying reaction to allergen were randomized to a single dose (one drop) of ketotifen fumarate in one eye and vehicle placebo in the fellow eye, followed by an allergen challenge at 15 min and 8 h post-dose. Subjects who had a qualifying reaction to allergen in the placebo-treated eye and a qualifying response to ketotifen in the active-treated eye following the single dose were re-randomized to a multiple-dose treatment period. They were instructed to instill one drop of ketotifen fumarate in one eye and placebo in the other eye twice daily for 4 wk. An allergen challenge was conducted 8 h after the last dose. The primary efficacy assessment was ocular itching, judged by the subject at 3, 7, and 10 min post-allergen challenge after single- and multiple-dose treatments. Other ocular signs and symptoms were assessed at 7, 10, and 15 min post-dose. A total of 133 subjects were randomized to single-dose treatment; 105 were evaluable for efficacy. Of these, 60 were re-randomized to multiple-dose treatment, and 55 were evaluable for efficacy. After single and multiple doses, ketotifen fumarate significantly inhibited ocular itching compared with placebo at all post-challenge timepoints (p < 0.001) and also significantly reduced hyperemia, chemosis, and lid swelling (p = 0.031). No drug-related systemic adverse events were reported, and ocular adverse events were comparable to placebo. No subject discontinued prematurely due to an adverse event. These results indicate that ketotifen fumarate 0.025% ophthalmic solution is an effective and safe treatment option for children with allergic conjunctivitis. [source] Laryngeal Findings in Users of Combination Corticosteroid and Bronchodilator Therapy,THE LARYNGOSCOPE, Issue 9 2004Natasha Mirza MD Educational Objective: At the conclusion of this article, the readers should be able to 1) describe the laryngeal findings in patients who use combination therapy for asthma, 2) discuss the mechanism of laryngeal irritation from the use of inhalers, and 3) describe possible mechanisms for reducing laryngeal irritation and secondary dysphonia from the use of inhalers. Objectives: To describe voice changes and laryngeal findings in patients who are started on combination corticosteroid and bronchodilator therapy in the form of a dry powder inhaler (DPI). Study Design: Retrospective, single-subject design. Methods: Retrospective review of 10 consecutive patients meeting inclusion criteria, who presented at the voice center with more than 4 weeks of dysphonia after being started on a combination form of asthma medication for control and maintenance therapy. All patients were nonsmokers and without history of previous identification or excision of vocal pathology. All patients were treated previously with a proton pump inhibitor for gastroesophageal reflux. Laryngeal videostroboscopic evaluations were performed on all patients. Patients were asked to complete a questionnaire regarding their perceived voice change and history of medical maintenance therapy for asthma. Results: Dysphonia was present in the patients selected for greater than 4 weeks. Patients had been switched to combination therapy after previously using traditional two-drug asthma regimens. In eight of nine patients, the vocal folds demonstrated areas of hyperemia, with plaque-like changes on the surface mucosa. Reduced amplitude of vibration and a reduction in mucosal wave propagation were present on videostroboscopy. Questionnaires revealed that all patients were initiated on combination DPI treatment within the last 6 months. Conclusions: Dysphonia caused by a change in the surface mucosa is a side effect from the use of DPI therapy for asthma. The high-impact force during inhalation of the medication and carrier leads to deposition of particles in the upper airway. We believe the extent of mucosal irritation can be minimized by patient education in the proper delivery of DPI. In some cases, however, return of the two medications delivered separately was necessary. The irritation of the laryngeal mucosa and return of normal vibratory parameters occurred in all patients. [source] Increased asymmetric dimethylarginine and endothelin 1 levels in secondary Raynaud's phenomenon: Implications for vascular dysfunction and progression of diseaseARTHRITIS & RHEUMATISM, Issue 7 2003Sanjay Rajagopalan Objective To compare microvascular and macrovascular functions in a cohort of patients with primary and secondary Raynaud's phenomenon (RP) who were matched for demographic, risk factor, and severity profiles. Methods Forty patients with primary or secondary RP matched for vascular risk factors and severity scores underwent testing of endothelial function and cold pressor responsiveness of the brachial artery. Microvascular perfusion of the digital vasculature was assessed using laser Doppler fluxmetry in response to reactive hyperemia. Plasma was assayed for endothelin 1 (ET-1), asymmetric dimethylarginine (ADMA), intercellular adhesion molecule 1, vascular cell adhesion molecule 1 (VCAM-1), and monocyte chemoattractant protein 1 (MCP-1). Results Patients with RP had abnormal vasoconstrictor responses to cold pressor tests (CPT) that were similar in primary and secondary RP. There were no differences in median flow-mediated and nitroglycerin-mediated dilation or CPT of the brachial artery in the 2 populations. Patients with secondary RP were characterized by abnormalities in microvascular responses to reactive hyperemia, with a reduction in area under the curve adjusted for baseline perfusion, but not in time to peak response or peak perfusion ratio. Plasma ET-1, ADMA, VCAM-1, and MCP-1 levels were significantly elevated in secondary RP compared with primary RP. There was a significant negative correlation between ET-1 and ADMA values and measures of microvascular perfusion but not macrovascular endothelial function. Conclusion Secondary RP is characterized by elevations in plasma ET-1 and ADMA levels that may contribute to alterations in cutaneous microvascular function. [source] Mesenteric Complications After Hypothermic Cardiopulmonary Bypass with Cardiac Arrest: Underlying MechanismsARTIFICIAL ORGANS, Issue 11 2002Terézia Bogdana Andrási Abstract: The aim of this study was to determine the pathophysiological mechanisms of postcardiopulmonary bypass (CPB) intestinal dysfunction using an in vivo canine model of extracorporeal circulation. Six dogs underwent a 90 min hypothermic CPB with continuous monitoring of mean arterial blood pressure (MAP) and mesenteric blood flow (MBF). Reactive hyperemia and vasodilator responses of the superior mesenteric artery to acetylcholine and sodium nitroprusside were determined before and after CPB. Mesenteric lactate production, glucose consumption, creatine kinase (CK) release and venous free radicals were determined. CPB induced a significant fall (p < 0.05) in MAP and MBF. After CPB, reactive hyperemia (,26 ± 15% versus ,53 ± 2%, p < 0.05) and the response to acetylcholine (,42 ± 9 versus ,55 ± 6%, p < 0.05) were significantly decreased. Reperfusion increased lactate production (0.8 ± 0.09 mmol/L versus 0.4 ± 0.18, p < 0.05) and the CK release (446 ± 98 U/L versus 5 ± 19 U/L, p < 0.01). Endothelial dysfunction, conversion from aerobic to anaerobic metabolism, and intestinal cell necrosis seem to be responsible for intestinal complications associated with CPB. [source] Gastric mucosal resistance to acute injury in experimental portal hypertensionBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2001Sara Calatayud The gastric mucosa of portal hypertensive rats exhibits important microvascular changes and a nitric oxide (NO)-dependent hyperemia. This study analyses whether portal hypertensive mucosa exhibits changes in its ability to withstand aggression. Portal hypertension was induced by partial portal vein ligation (PPVL) or common bile duct ligation (CBDL) and gastric damage was induced by oral administration of ethanol or aspirin. Experiments were performed in conscious or anaesthetized rats and some animals were pre-treated with the NO-synthesis inhibitor L -NAME. Conscious PPVL or CBDL rats showed an increased resistance to the damaging effects of ethanol. Oral administration of aspirin produced less gastric damage in PPVL conscious rats than in the control group. The protective effects of portal hypertension were maintained in animals anaesthetized with ketamine and absent when pentobarbital was employed. Pre-treatment with L -NAME restored the damaging effects of ethanol and aspirin in PPVL rats without modifying the level of damage in control animals. Gastric bleeding induced by oral aspirin, as measured by the luminal release of 51Cr-labelled erythrocytes, was significantly greater in PPVL rats than in control animals. Semi-quantitiative analysis by RT , PCR of the mRNA for endothelial NO-synthase (eNOS), neuronal NOS (nNOS) and inducible NOS (iNOS) levels showed that the expression of iNOS was slightly increased in both the gastric mucosa and smooth muscle of PPVL rats. No changes were observed in eNOS and nNOS expression. Conscious portal hypertensive rats exhibit an enhanced resistance to acute gastric damage which is absent under the influence of some types of anaesthesia and seems related to an increased synthesis of nitric oxide. However, mucosal lesions in these animals show an augmented bleeding per area of injury. British Journal of Pharmacology (2001) 132, 309,317; doi:10.1038/sj.bjp.0703785 [source] | ||||||||||||||||||||||||||||