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Cold Pressor Test (cold + pressor_test)
Selected AbstractsEstimation of Coronary Flow Velocity Reserve Using Transthoracic Doppler Echocardiography and Cold Pressor Test Might Be Useful for Detecting of Patients with Variant AnginaECHOCARDIOGRAPHY, Issue 4 2010Hui-Jeong Hwang M.D. Purpose: The cold pressor test (CPT) has been used to detect variant angina, but its sensitivity in predicting vasospasm is low. The aim of this study was to determine whether estimates of the coronary flow velocity reserve (CFVR) in the distal left anterior descending coronary artery (dLAD) using transthoracic echocardiography (TTE) and CPT are useful tool to predict variant angina. Methods: 65 patients (mean age = 52 ± 10 years; male:female = 41:24) who had normal coronary artery on angiography and underwent acetylcholine provocation test were enrolled and divided into the spasm group (n = 31) and the no spasm group (n = 34). During CPT, the peak (PDV) and mean diastolic flow velocity (MDV) of the dLAD were estimated using TTE with a high-frequency transducer, and electrocardiography, blood pressures, heart rate, and symptoms were monitored every 30 seconds. CPT%PDV and CPT%MDV were defined as the percentage changes in PDV and MDV during CPT, respectively. Results: CPT%PDV was 4.99 ± 23.62% in the spasm group and 52.75 ± 24.78% in the no spasm group (P < 0.001). CPT%MDV was 6.83 ± 23.81% in the spasm group and 50.22 ± 27.83% in the no spasm group (P < 0.001). CPT%PDV<31.1% had a sensitivity of 93.5% and a specificity of 82.4% in predicting variant angina (95% confidence interval [CI]: 0.939,0.979, P < 0.001). CPT%MDV<30.55% had a sensitivity of 90% and a specificity of 76.5% in predicting variant angina (95% CI: 0.884,0.950, P < 0.001). Conclusion: The measurement of changes in the coronary flow velocity of the dLAD using TTE and CPT might be useful for the estimation of endothelial dysfunction in patients with variant angina. (ECHOCARDIOGRAPHY 2010;27:435-441) [source] The role of the ,-adrenergic receptor in the leg vasoconstrictor response to orthostatic stressACTA PHYSIOLOGICA, Issue 3 2009M. Kooijman Abstract Aim:, The prompt increase in peripheral vascular resistance, mediated by sympathetic ,-adrenergic stimulation, is believed to be the key event in blood pressure control during postural stress. However, despite the absence of central sympathetic control of the leg vasculature, postural leg vasoconstriction is preserved in spinal cord-injured individuals (SCI). This study aimed at assessing the contribution of both central and local sympathetically induced ,-adrenergic leg vasoconstriction to head-up tilt (HUT) by including healthy individuals and SCI, who lack central sympathetic baroreflex control over the leg vascular bed. Methods:, In 10 controls and nine SCI the femoral artery was cannulated for drug infusion. Upper leg blood flow (LBF) was measured bilaterally using venous occlusion strain gauge plethysmography before and during 30° HUT throughout intra-arterial infusion of saline or the non-selective ,-adrenergic receptor antagonist phentolamine respectively. Additionally, in six controls the leg vascular response to the cold pressor test was assessed during continued infusion of phentolamine, in order to confirm complete ,-adrenergic blockade by phentolamine. Results:, During infusion of phentolamine HUT still caused vasoconstriction in both groups: leg vascular resistance (mean arterial pressure/LBF) increased by 10 ± 2 AU (compared with 12 ± 2 AU during saline infusion), and 13 ± 3 AU (compared with 7 ± 3 AU during saline infusion) in controls and SCI respectively. Conclusion:, Effective ,-adrenergic blockade did not reduce HUT-induced vasoconstriction, regardless of intact baroreflex control of the leg vasculature. Apparently, redundant mechanisms compensate for the absence of sympathetic ,-adrenoceptor leg vasoconstriction in response to postural stress. [source] Cardiac autonomic dysinnervation and myocardial blood flow in long-term Type 1 diabetic patientsDIABETIC MEDICINE, Issue 5 2003N. Hattori Abstract Aims The aim of the study was to assess scintigraphically the relationship between myocardial blood flow response and sympathetic dysinnervation in long-term Type 1 diabetic patients. Effects of the iron chelator deferoxamine on myocardial blood flow were studied and they were investigated according to the presence of cardiac sympathetic dysfunction. Methods Myocardial blood flow (MBF) was assessed with N-13 ammonia positron emission tomography in 13 long-term Type 1 diabetic patients and 13 control subjects at rest and in response to sympathetic stimulation (cold pressor test (CPT)). In diabetic patients, the study was repeated after preinfusion with deferoxamine. Furthermore, 123I metaiodobenzylguanidine (MIBG) scintigraphy was applied to assess regional cardiac sympathetic dysinnervation (uptake score 1 = normal, homogeneous uptake , 6 = no uptake). Results In diabetic patients, MBF increased in response to CPT from 78 ± 18 ml/100 g/min to 84 ± 26 ml/100 g (8%, P < 0.001). Control subjects demonstrated an increase from 63 ± 17 ml/100 g to 84 ± 26 ml/100 g (33%, P < 0.001), respectively. Resting MBF was higher in diabetic patients than in control subjects (P < 0.001). In diabetic patients, increase in MBF in response to CPT was significant in regions with a MIBG uptake score of , 3. Regions with a MIBG uptake score of > 3 did not exhibit a significant increase in MBF in response to CPT. After administration of deferoxamine, the increase in MBF in response to CPT was 23% and the magnitude of increase was related to the MIBG uptake score (r = 0.40, P < 0.0001). Conclusions Myocardial blood flow response to sympathetic stimulation is significantly impaired in long-term Type 1 diabetes. After preinfusion with deferoxamine the impairment is partially reversed and a relationship between myocardial blood flow and the extent of cardiac sympathetic dysfunction is observed. Diabet. Med. 20, 375,381 (2003) [source] Sweet preferences and analgesia during childhood: effects of family history of alcoholism and depressionADDICTION, Issue 4 2010Julie A. Mennella ABSTRACT Aim To determine whether depression and family history of alcoholism are associated with heightened sweet preferences in children, before they have experienced alcohol or tobacco and at a time during the life-span when sweets are particularly salient. Design Between- and within-subject experimental study. Participants Children, 5,12 years old (n = 300), formed four groups based on family history of alcohol dependence up to second-degree relatives [positive (FHP) versus negative (FHN)] and depressive symptoms as determined by the Pictorial Depression Scale [depressed (PDEP) versus non-depressed (NDEP)]. Measurements Children were tested individually to measure sucrose preferences, sweet food liking and, for a subset of the children, the analgesic properties of sucrose versus water during the cold pressor test. Findings The co-occurrence of having a family history of alcoholism and self-reports of depressive symptomatology was associated significantly with a preference for a more concentrated sucrose solution, while depressive symptomatology alone was associated with greater liking for sweet-tasting foods and candies and increased pain sensitivity. Depression antagonized the analgesic properties of sucrose. Conclusions While children as a group innately like sweets and feel better after eating them, the present study reveals significant contributions of family history of alcoholism and depression to this effect. Whether the heightened sweet preference and the use of sweets to alleviate depression are markers for developing alcohol-related problems or responses that are protective are important areas for future research. [source] Autonomic skin responses in females with Fabry diseaseJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 3 2009Anette T. Møller Abstract Fabry disease is a genetic lysosomal disorder with dysfunction of the lysosomal enzyme ,-galactosidase A causing accumulation of glycolipids in multiple organs including the nervous system and with neuropathy as a prominent manifestation. Neurological symptoms include pain and autonomic dysfunction. This study examined peripheral autonomic nerve function in 19 female patients with Fabry disease and 19 sex and age-matched controls by measuring (1) sweat production following acetylcholine challenge; (2) the sympathetically mediated vasoconstrictor responses to inspiratory gasp, stress, and the cold pressor test; and (3) cutaneous blood flow following capsaicin. The vasoconstrictor response to inspiratory gasp was increased in Fabry patients compared to controls (p = 0.03), while the response to cold and mental stress did not change. Female patients with Fabry disease had a reduced sweat response to iontophoresis of acetylcholine (p = 0.04) and a smaller capsaicin-induced flare compared to controls. These findings suggest that female patients both have an impaired C-fiber function and local abnormalities in blood vessels and sweat glands. [source] Reductions in basal limb blood flow and vascular conductance with human ageing: role for augmented ,-adrenergic vasoconstrictionTHE JOURNAL OF PHYSIOLOGY, Issue 3 2001Frank A. Dinenno 1Basal whole-limb blood flow and vascular conductance decrease with age in men. We determined whether these age-associated changes in limb haemodynamics are mediated by tonically augmented sympathetic ,-adrenergic vasoconstriction. 2Seven young (28 ± 2 years; mean ±s.e.m.) and eight older (64 ± 2 years) healthy, normotensive adult men were studied. Baseline femoral artery blood flow (Doppler ultrasound) and calculated vascular conductance were 29 and 31 % lower, respectively, and vascular resistance was 53 % higher in the older men (all P < 0.001). 3Local (intra-femoral artery) ,-adrenergic receptor blockade with phentolamine evoked greater increases in femoral blood flow (105 ± 11 vs. 60 ± 6 %) and vascular conductance (125 ± 13 vs. 66 ± 7 %), and reductions in vascular resistance (55 ± 2 vs. 39 ± 3 %) in the experimental limb of the older compared with the young men (all P < 0.001). As a result, ,-adrenergic receptor blockade eliminated the significance of the age-associated differences in absolute levels of femoral blood flow (500 ± 51 vs. 551 ± 35 ml min,1), vascular conductance (6.02 ± 0.73 vs. 6.33 ± 0.26 U), and vascular resistance (0.17 ± 0.03 vs. 0.16 ± 0.01 U; P= 0.4,0.8, n.s.). Femoral haemodynamics in the control limb were unaffected by phentolamine administration in the contralateral (experimental) limb. Complete ,-adrenergic receptor blockade was demonstrated by the absence of vasoconstriction in the experimental limb in response to the cold pressor test. Local propranolol was administered to control for any ,-adrenergic effects of phentolamine. Propranolol did not affect haemodynamics in the experimental or control limbs. 4Our results indicate that the age-related reductions in basal limb blood flow and vascular conductance are mediated largely by chronically elevated sympathetic ,-adrenergic vasoconstriction. This may have important physiological and pathophysiological implications for the ageing human. [source] Autonomic dysfunction in presymptomatic and early symptomatic Huntington's diseaseACTA NEUROLOGICA SCANDINAVICA, Issue 6 2010J. Kobal Kobal J, Melik Z, Cankar K, Bajrovic FF, Meglic B, Peterlin B, Zaletel M. Autonomic dysfunction in presymptomatic and early symptomatic Huntington's disease. Acta Neurol Scand: 2010: 121: 392,399. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives,,, Although autonomic dysfunction was found in advanced Huntington's disease (HD) patients it is not clear whether there is autonomic dysfunction in presymptomatic and early symptomatic HD. Material & methods,,, Different cardiovascular autonomic tests were performed in 14 presymptomatic HD mutation carriers (PHD), 11 early symptomatic HD patients (EHD) and in 25 sex and age matched controls. Results,,, We found attenuated response to simple mental arithmetic test (relative heart rate in PHD and EHD was 10% lower than in controls; diastolic pressure was 10.6% lower in EHD than in controls; P < 0.05) and exaggerated response to the late phase of cold pressor test (relative heart rate was 10% higher in PHD and 7% higher in EHD than in controls; P < 0.05). The rest of the cardiovascular autonomic tests did not reveal significant differences between patients and controls. Conclusions,,, Our results suggest that subtle autonomic dysfunction occurs even in PHD and EHD. [source] Assessment of coronary blood flow and the reactivity of the microcirculation non-invasively with transthoracic echocardiographyCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 3 2008Tuomas Kiviniemi Summary Background:, The development in ultrasound technology has allowed the use of non-invasive transthoracic echocardiography (TTE) for the study of coronary artery physiology and pathophysiology. TTE can be used to detect atherosclerotic changes in epicardial coronary arteries and to study the effects of specific interventions on coronary microcirculation. Aim:, The purpose of this review was to summarize the development of TTE, and outweigh the strenghts and weaknesses of the method for the evaluation of coronary artery blood flow. Moreover, findings from clinical trials studying microcirculatory reactivity using TTE are presented. Conclusions:, TTE is a feasible and reproducible method for the evaluation of coronary artery blood flow. It can also be used in assessing the vasodilation of the epicardial coronary artery simultaneously with flow velocity measurement during the cold pressor test and coronary flow velocity reserve assessment. It is specifically suitable for repeated measurements in interventional trials. [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] | |||||||||||||