Evaluation of the severity of chronic heart failure by the reactivity of peripheral vessels.

We developed a method to evaluate the severity of chronic cardiac failure by Doppler image analysis. Doppler images of the whole arterial lumen were consecutively recorded on video tape and the power spectrum (sum of intensity multiplied by frequency) of each frame was considered as an index of the blood flow volume (VI). The right brachial artery was occluded for 15-60 seconds by a occluding cuff, and was released quickly. The VI was determined until the VI returned to the level at rest and total VI was calculated as an O2 repayment. The O2 repayment rate (R-Rate) was calculated as a ratio of the O2 repayment divided by total VI during interruption. The cardiac function was evaluated by sub-maximal exercise using bicycle ergometer and was compared with the R-Rate. The subjects were 22 patients (18 males and 4 females) with chronic cardiac failure of NYHA class I (9), class II (6), class III (4), class IV (3) and 12 healthy controls. R-Rate was almost unchanged by the duration of occlusion and showed positive correlation with exercise capacity. R-Rate decreased as the class of NYHA advanced. In conclusion, determination of reactive hyperemia can be used for objectively evaluating the severity of cardiac failure. Doppler sonography; cardiac failure; reactive hyperemia; peripheral circulation     

A comparison of the effects of vasodilator stimuli on peripheral resistance vessels in normal subjects and in patients with congestive heart failure

The objective of this investigation was to characterize the mechanism of peripheral vasoconstriction observed in heart failure and to determine whether it can be attributed to the augmented sympathetic nervous activity, characteristic of this state. The response of the resistance bed in the forearm after release of inflow occlusion (reactive hyperemia), to hand exercise, and to local heating and the response of the calf resistance vessels to arterial occlusion and intra-arterial sodium nitrite and phentolamine were studied in 23 patients with congestive heart failure and 21 normal subjects. In the normal subjects, reactive hyperemia blood flow after varying periods of arterial occlusion greatly exceeded the values observed in patients with heart failure. Local anesthetic blockade and intra-arterial phentolamine did not significantly alter the reactive hyperemia response in heart failure patients, militating against the possibility that increased sympathetic vasoconstrictor activity is responsible for the reduction of this response. Following compensation, the reactive hyperemia response returned toward normal. The striking elevations of the forearm blood flow observed after hand exercise and heating of the forearm in normal subjects were also markedly attenuated in patients with heart failure. Following intra-arterial phentolamine and/or sodium nitrite, peak calf blood flow was still significantly reduced in heart failure.These observations indicate that (1) heart failure is characterized by a striking reduction in the response to a variety of endogenous and exogenous vasodilator stimuli; (2) circulating catecholamines and sympathetic vasoconstrictor activity are not solely responsible for the elevation of peripheral vascular resistance and the reduced response to vasodilator stimuli in heart failure; and (3) heart failure may increase systemic vascular resistance directly by altering the mechanical properties and reducing the dilating ability of the resistance vessels.     

Effect of distal occlusions on the assessment of aorto-iliac pathology by analysis of doppler spectra

In patients with multilevel arterial obstructive disease, assessment of the severity and location of the pathology is a difficult diagnostic problem. As reported recently, the intra-arterial pressure in the common femoral artery may become normal, although aorto-iliac obstructive disease is present if the superficial femoral artery is occluded. Aorto-iliac obstructive disease can also be assessed by analysis of Doppler spectra obtained from the common femoral artery. In this study, we evaluate if this assessment of aorto-iliac obstructive disease is also harmfully affected by an occlusion in the superficial femoral artery. The results of this study demonstrate that some Doppler parameters (such as acceleration time, slope of the acceleration phase, and the resistance index), which are essential for the assessment of aorto-iliac obstructive disease, are not significantly affected by an occlusion in the superficial femoral artery. Moreover, the study shows that the status of the superficial femoral artery may also be assessed by analysis of Doppler spectra obtained from the common femoral artery.     

原发性高血压及高血压合并高胆固醇血症血管内皮功能的超声研究

目的 探讨原发性高血压及高血压合并高胆固醇血症患者血管内皮依赖性舒张功能的改变。方法 采用彩色多普勒高频超声的间歇成像和能量多普勒成像，对24例原发性高血压患者（EH组）、24例高血压合并高胆固醇血症患者（EH＋HC组）及24例正常血压、血胆固醇者（NT组）的血管内皮依赖性舒张功能，包括静息时血管内径（BD）、增加流量引起的血管舒张（FMD）、服用硝酸甘油引起的血管舒张（GTN）等，以及对血浆一氧化氮（NO）、内皮素（ET）、血栓素B2（TXB2）和前列腺环素（PGI2）等血管活性物质进行检测并比较分析。结果 EH和EH＋HC组反应性充血引起的FMD值明显减弱，与NT组比较差异有非常显著性（均P〈0．01），EH与EH＋HC组之间比较差异亦有统计学意义（P〈0．05）；含服硝酸甘油后肱动脉内径明显扩张，但各组间GTN值差异无统计学意义（P〉0．05）；EH＋HC、EH组与NT组比较血浆中NO、PGI2水平明显降低，而ET、TXB2水平明显升高（均P〈0．01），EH＋HC与EH组间比较差异亦有统计学意义（P〈0．05）。结论 高血压患者存在血管内皮依赖性舒张功能受损，高血压合并高胆固醇血症时，内皮功能受损进一步加重。彩色多普勒超声是评价血管内皮舒张功能的简单、无创且可靠方法。     

同种异体肾移植患者肱动脉内皮依赖性舒张功能损伤的研究

目的 研究同种异体肾移植患者肱动脉内皮依赖性舒张功能损伤。方法 应用高频超声分别探测肾移植术后应用环孢素A抗排异、肾移植术后应用他克莫司(FK-506)抗排异及正常对照3组患者静息条件下、反应性充血后及舌下含服硝酸甘油后肱动脉内径及内径变化，从而判断肱动脉内皮依赖性舒张功能。结果 反应性充血后，肾移植术后患者肱动脉内径舒张的绝对值及相对值均明显小于正常对照，含服硝酸甘油后3组患者肱动脉内径的舒张差别无显著性意义。应用环孢素A抗排异与应用FK-506抗排异组在反应性充血后肱动脉内径的绝对值与相对值差异无显著性意义。结论 同种异体肾移植患者肱动脉内皮依赖性舒张功能受到损伤。     

Chronic effects of labetalol, pindolol, and propranolol on calf blood flow in intermittent claudication

To evaluate the role of beta-adrenoceptor blockade on lower limb circulation in patients with peripheral arterial disease, heart rate, blood pressure, calf blood flow and vascular resistance were measured at rest and during reactive hyperemia in seven patients with hypertension and intermittent claudication. The study was performed as a placebo-controlled, double-blind, crossover trial of 10 days with doses of propranolol, 80 mg twice a day, pindolol, 5 mg twice a day, labetalol, 200 mg twice a day, and labetalol, 400 mg twice a day as active drug. Heart rate was lowest during propranolol dosing and blood pressure was lowest during labetalol dosing irrespective of the labetalol dose used. The degree of peripheral arterial disease modulated the effect of beta-blockade on limb circulation. In the less symptomatic limbs, reactive hyperemic flow was greater after pindolol than after the other drugs and did not differ from the level recorded after placebo. These differences were inconsistent and small in the more symptomatic limbs. Thus as the peripheral arterial disease became more severe and extensive, beta-blockade, irrespective of its type, lost its hemodynamic effect on lower limb circulation.     

彩色多普勒超声检测长期吸烟者的肱动脉内皮功能

目的多普勒超声检测长期吸烟者的肱动脉内皮细胞功能。方法采用超声显像法对29例长期吸烟者和22例正常对照组作肱动脉测定基础状态下血管内径、反应性充血时的内径及舌下含服硝酸甘油后的血管内径。结果长期吸烟者反应性充血诱发的肱动脉内径变化百分率明显低于对照组P<0.01。服药后诱发血管扩张内径变化百分率也低于对照组P<0.01。结论长期吸烟者血管内皮功能受损,硝酸甘油诱发的扩血管反应也有所下降。     

老年心力衰竭患者血管内皮舒张功能变化及临床意义

目的：通过对慢性心力衰竭（CHF）病人血流介导性肱动脉内皮舒张功能（FMD）的测定,探讨心衰病人FMD的变化及其与心力衰竭的关系和临床意义。方法：随机选择心衰患者50例,健康人20例。采用美国菲利普7500型超声心动图仪检测肱动脉基础状态下、反应性充血时（内皮依赖性舒张）及含服硝酸甘油后（非内皮依赖性舒张）的内径。计算反应性充血时肱动脉内径舒张百分比及含服硝酸甘油后肱动脉内径舒张百分比。结果：与正常组比较,心衰组FMD均显著降低（P〈0.05）,心功能越差,FMD降低越明显。结论：老年慢性心衰患者存在内皮功能障碍,改善内皮功能对于心力衰竭的防治具有重要临床意义。     

Hemodynamic effects of intermittent intra-arterial infusion treatment with prostaglandin E1 in peripheral arterial occlusive disease

14 femoral arteries of twelve patients with peripheral arterial occlusive disease (Fontaine stage II: n = 4, stage III/IV: n = 10) were investigated before, immediately after a series of 26 (ten to 52) intraarterial infusions with prostaglandin E1, and 30 weeks later. Using combined B-mode and pulsed Doppler (duplex) ultrasound blood flow measurements were performed in the common femoral, the superficial femoral, and the deep femoral artery. There was a significant decrease of resting blood flow volume in the common femoral artery after therapy (418.5----362.2 [p less than 0.01]----324.5 ml/min [p less than 0.05]) in the group of patients treated successfully. The peak flow (maximum value of blood flow volume during reactive hyperaemia) in the common femoral artery increased significantly after therapy (597.3----779.1 [p less than 0.05]----843.7 ml/min). The increase of peak flow correlated well with clinical improvement. Other parameters (blood flow velocities, pulse rise time, pulse decrease time, pulsatility index) changed without correlation to clinical outcome. The increase of peak flow after therapy might be caused by an improved collateral circulation, and the decrease of resting blood flow might be due to metabolic effects of prostaglandin E1 (improved oxygen utilization).     

Alterations in the peripheral circulation in COPD patients

RATIONALE: Although various factors influence peripheral circulation in chronic obstructive pulmonary disease (COPD) patients, little is known about the vasomotor changes in these subjects. OBJECTIVES: The present study was designed to assess alterations in the brachial circulation of COPD patients. METHODS: Twenty-five COPD patients and 25 healthy subjects were studied. Brachial artery (BA) blood flow and indices of BA stiffness were investigated by two-dimensional ultrasonography and pulsed Doppler. Cardiac dimensions, left ventricular (LV) function and cardiac output were assessed by pulsed Doppler echocardiography. MAIN RESULTS: A significant increase in LV mass was observed in the COPD group despite normal arterial pressure. Total arterial compliance and BA compliance were significantly decreased in COPD patients in comparison with healthy subjects. Heart rate was increased in COPD patients and was inversely correlated with PaO(2) and forced expiratory volume in the first second (FEV(1)). A decrease in LV preload was expressed by a reduction in LV diastolic diameters and LV stroke volume. Patients with severe COPD have a lower BA surface area than patients with moderate COPD. FEV(1) and PaO(2) were significantly related to BA compliance. CONCLUSION: In COPD patients, significant alterations in the peripheral circulation were observed. Moreover, the magnitude of changes in the peripheral circulation was related to the severity of COPD.     

Microvascular response in patients with cardiogenic shock

OBJECTIVE: To examine the mechanisms contributing to decreased microvascular blood flow in cardiogenic shock by comparing patients with cardiogenic shock with critically ill controls and with patients with septic shock. DESIGN: Prospective, consecutive entry of patients meeting the criteria for septic shock, cardiogenic shock, and critical illness without coexisting infection or shock. SETTING: University hospital, medical intensive care unit, coronary care unit, and respiratory care unit. PATIENTS: Eight patients with cardiogenic shock secondary to acute myocardial infarction, six critically ill controls, and six patients with septic shock. MEASUREMENTS AND MAIN RESULTS: Forearm blood flow was measured at rest and during reactive hyperemia by venous air plethysmography. Red cell deformability was determined by filtration. Leukocyte aggregation was detected by the leukergy test. Neutrophil CD11b/CD18 expression and soluble intercellular adhesion molecule-1 levels were also measured. In cardiogenic shock, forearm arterial resistance was significantly increased at rest and during reactive hyperemia compared with controls and patients with septic shock. The response to reactive hyperemia was attenuated in cardiogenic and septic shock patients, as measured by the absolute change in forearm blood flow from baseline, which was significantly less as compared with controls (p < .01). The percent change in forearm blood flow during reactive hyperemia compared with forearm blood flow at rest was significantly lower in cardiogenic shock (60+/-10) and in septic shock (50+/-11) compared with controls at baseline (145+/-20; p < .01). Red cell deformability was significantly decreased in cardiogenic shock (1.2+/-0.2 mL/min; p < .05) and septic shock (1.1+/-0.2 mL/min; p < .05), compared with controls (1.8+/-0.1 mL/min). Neutrophil CD11b/CD18 expression, leukergy, and serum intercellular adhesion molecule-1 levels in cardiogenic shock patients were not significantly different from controls. CONCLUSION: These data suggest that the response to reactive hyperemia is attenuated in cardiogenic shock. This appears to reflect increased vasoconstriction and an impaired capacity for vasodilation. Decreased erythrocyte deformability may also be important in limiting systemic microvascular flow. However, evidence supporting a role for neutrophil-endothelial cell interactions was not observed.     

体外膜肺氧合在成人心脏手术术后心力衰竭治疗中的应用

目的:观察体外膜肺氧合(extracorporeal membrane oxygenation,ECMO)对成人心脏手术术后心力衰竭患者的治疗效果,探讨在此类患者应用ECMO的适应证。方法:自2006年11月—2007年1月,对3例成人心脏术后心力衰竭的患者进行ECMO支持治疗,均采用股动-静脉插管。ECMO期间维持血流动力学和呼吸指标稳定。结果:ECMO时间平均102.3h。3例患者心功能改善、均顺利脱机。1例康复出院,1例脱机31d后因严重肺部感染死亡,1例脱机5d后因心律失常死亡。结论:ECMO是治疗成人心脏术后心功能衰竭的有效方法,但需正确掌握适应证,合理选择患者。     

Monitoring Muscle Perfusion in Rodents During Short-Term Ischemia Using Power Doppler Ultrasound

ObjectiveThe aim of this work was to evaluate the reliability of power Doppler ultrasound (PD-US) measurements made without contrast enhancement to monitor temporal changes in peripheral blood perfusion.MethodsOn the basis of pre-clinical rodent studies, we found that combinations of spatial registration and clutter filtering techniques applied to PD-US signals reproducibly tracked blood perfusion in skeletal muscle. Perfusion is monitored while modulating hindlimb blood flow. First, in invasive studies, PD-US measurements in deep muscle with laser speckle contrast imaging (LSCI) of superficial tissues made before, during and after short-term arterial clamping were compared. Then, in non-invasive studies, a pressure cuff was employed to generate longer-duration hindlimb ischemia. Here, B-mode imaging was also applied to measure flow-mediated dilation of the femoral artery while, simultaneously, PD-US was used to monitor downstream muscle perfusion to quantify reactive hyperemia. Measurements in adult male and female mice and rats, some with exercise conditioning, were included to explore biological variables.ResultsPD-US methods are validated through comparisons with LSCI measurements. As expected, no significant differences were found between sexes or fitness levels in flow-mediated dilation or reactive hyperemia estimates, although post-ischemic perfusion was enhanced with exercise conditioning, suggesting there could be differences between the hyperemic responses of conduit and resistive vessels.ConclusionOverall, we found non-contrast PD-US imaging can reliably monitor relative spatiotemporal changes in muscle perfusion. This study supports the development of PD-US methods for monitoring perfusion changes in patients at risk for peripheral artery disease.     

幼年型Ⅰ型糖尿病患者血管内皮功能的彩色多普勒超声研究

目的　应用彩色多普勒超声探讨 型糖尿病 (IDDM)幼年型患者内皮功能及与血糖间的关系。方法　测量 4 2例 型糖尿病幼年型患者的空腹血糖值后 ,测定其反应性充血时和口内喷服硝酸甘油气雾剂后测量肱动脉内径的变化 ,并对其进行相关性分析。结果　 型糖尿病幼年型患者反应性充血及口内喷服硝酸甘油气雾剂后肱动脉内径的变化均有显著的统计学意义 (P<0 .0 1)。相关性分析显示空腹糖化血红蛋白与内皮功能呈负相关 ,特别是餐后 2 h血糖值 ,r=- 0 .4 5 1,- 0 .6 84。结论　 型糖尿病幼年型患者的血管内皮依赖性及非依赖性舒张功能均有明显的损伤。且随着血糖的增高损伤程度加重。     

急性心力衰竭绵羊搏动性导管泵辅助肾缺血-再灌注后的形态学改变

背景:有关心力衰竭辅助循环后出现急性肾功能衰竭的报道较多,但在该背景下对肾脏组织的形态学分析却鲜有文献涉及.目的:建立绵羊急性心力衰竭模型,在此背景下于国内首次观察搏动性导管泵短期辅助后缺血一再灌注肾脏的形态学改变.设计、时间及地点:自身对照动物实验,于2003-07/2004-04在上海第二医科大学附属仁济医院心血管外科研究室完成.材料:搏动性导管泵由欧洲人工脏器协会主席、荷兰Groningen大学生物医学工程教授、搏动性导管泵发明者GerhardRakhorst提供.方法:取10只绵羊进行左心衰竭诱导,建立肾缺血一再灌注模型,建模成功后开始搏动性导管泵辅助,辅助持续3 h.主要观察指标:分别于心力衰竭前、心力衰竭时及辅助后每隔45 min监测并记录血流动力学参数:辅助3h后取肾脏行光镜和电镜观察.结果:10只绵羊中7只成功支持达到规定的时间.成功的7只绵羊在支持期间血流动力学逐步恢复并趋向稳定,血压接近正常的基线值.光镜和电镜检查发现肾脏缺血一再灌注后轻度的急性改变,主要表现为肾小球细胞数量增多,血管扩张充血,肾曲管上皮水肿变性;肾髓质血管扩张充血,间质水肿.结论:急性心力衰竭绵羊经短期辅助后虽恢复了血流动力学指标,但肾脏病理改变依然存在,提示在辅助循环期间,仅凭血流动力学的稳定来判断肾功能的预后是不可靠的.     

彩色多普勒超声检查评价高海拔地区居住不同年限人群肱动脉内皮功能

目的应用彩色多普勒超声检查评价高海拔地区居住不同年限人群血流介导血管舒张功能。方法应用高频彩色多普勒超声检查检测海拔高度3000m以上294例居住不同年限人群肱动脉反应性充血前后血管内径、血流速度、血流量、血管阻力指数(RI)、心率,分析肱动脉血管内皮依赖性舒张(EDD)功能,并与100例海拔高度1560m居民(对照组)进行比较。结果高海拔地区居住1～2年组人群肱动脉基础内径为(3.97±0.41)cm,3～4年组为(3.87±0.30)cm,≥5年组为(3.69±0.57)cm,前2组与对照组比较差异无统计学意义,≥5年组肱动脉基础内径低于对照组(P0.05)。1～2年组反应性充血时肱动脉内径的扩张程度为(12.42±3.13)%,3～4年组为(11.62±1.03)%,与对照组的(10.30±1.02)%相比无统计学差异;而≥5年组为(12.58±1.90)%,显著低于对照组(P0.01)。结论高海拔地区居住时间不同肱动脉检测指标也不同,久居高原低氧环境EDD功能下降。     

The level of C-reactive protein and major artery elasticity in patients with ischemic heart disease

AIM: To assess elasticity of the major arteries in patients with ischemic heart disease (IHD) with reference to concentration of C-reactive protein (CRP). MATERIAL AND METHODS: A total of 52 IHD males (mean age 54 +/- 1.58 years) with functional class I-III angina pectoris and heart failure entered the trial. Major artery elasticity was defined by velocity of the pulse wave. Response of the major arteries (a. radialis) to circulation intensification was evaluated with reactive hyperemia test. Concentration of CRP was determined by enzyme immunoassay. RESULTS: There is a significant correlation between pulse wave velocity for elastic arteries and the levels of C-reactive protein (r = 0.34; p = 0.018). In investigation of endothelium-dependent reactivity we detected significant changes in the response of muscular-type artery to enhancement of blood flow. CRP concentration significantly correlated with pulse wave velocity inhibition in response to blood flow intensification (r = 0.49; p = 0.0005). CONCLUSION: Elevation of C-reactive protein in blood plasma of IHD patients may point to marked changes in elasticity of major arteries. Simultaneous assessment of lipid spectrum and CRP enhances diagnostic significance of each index, separately.     

Effect of glutathione infusion on leg arterial circulation,cutaneous microcirculation,and pain-free walking distance in patients with peripheral obstructive arterial disease: a randomized,double-blind,placebo-controlled trial

OBJECTIVE: To assess the effects of glutathione on pain-free walking distance (PFWD) and hemodynamic parameters in patients with peripheral artery disease. PATIENTS AND METHODS: Forty patients with Fontaine stage II peripheral artery disease who were seen between September 2000 and March 2001 at the vascular laboratory and ward of the Division of Vascular Medicine and Rehabilitation at Verona University were studied in a double-blind, placebo-controlled trial. The patients were randomly assigned (20 per group) to treatment with intravenous glutathione twice a day or saline solution twice a day for 5 days. Treatments were administered in a double-blind manner. The 2 groups of patients underwent measurement of PFWD by strain-gauge plethysmography and laser Doppler flowmetry (with postischemic test) of the symptomatic leg at rest and after treadmill test. All measurements and tests were repeated 12 hours after the last infusion. RESULTS: Between the 2 groups, hemodynamic tests showed no differences in baseline values and at rest after treatment. At rest, no differences were observed between basal and posttreatment values; findings in the saline group were similar during tests before and after the infusion period. In the glutathione group, we observed increases in PFWD (196+/-15 vs 143+/-11 m; P<.04), macrocirculatory flow after treadmill test with plethysmography at the end of treatment (9.3+/-2 vs 2.8+/-0.5 mL per 100 mL/min; P<.002), and postischemic hyperemia with laser Doppler flowmetry, registered as perfusion units (PU), at the end of infusions (14.4+/-3.2 vs 6.18+/-1.5 PU; P<.005), with a greater area under the curve after treatment (705+/-103 vs 508+/-45 PU/s; P<.001) and reduced time to flow motion (32+/-4 vs 48+/-11 seconds; P<.05). CONCLUSION: In patients with peripheral artery disease, glutathione prolongs PFWD and shows an improvement of macrocirculatory and microcirculatory parameters.     

Blood flow velocity and vascular resistance during passive leg exercise in the critically ill patient

Passive range of motion exercise is a very common physical therapy treatment for patients admitted to an intensive care unit. However is the knowledge scarce regarding its impact on blood circulation in the extremities. The objective of this study was therefore to investigate the effect of passive range of motion on arterial peripheral leg blood flow velocity (BFV) and vascular resistance. A cross-sectional consecutive study of twelve patients admitted to an intensive care unit and twelve healthy age- and gender-matched controls was conducted. Passive range of motion was performed in one leg by a physical therapist. Blood flow velocities and resistance index in the common femoral artery (CFA), blood pressure and heart rate were measured before, directly after and at rest after passive range of motion. No changes were seen in BFV or resistance index in the patient group or the control group. No changes were found in blood pressure or heart rate in the patient group. In the control group, changes were found in systolic and mean blood pressure, with a higher pressure before passive range of motion. The controls had lower BFV and higher resistance index than the patients when comparing the groups. The conclusion of this study including twelve patients is that passive range of motion does not alter BFV or resistance index in the CFA in comatose and/or sedated critically ill patients.     

初诊2型糖尿病患者动脉内膜中层厚度和血管内皮功能的超声研究

目的应用高分辨率超声检测和评估初诊2型糖尿病患者的动脉内膜中层厚度(IMT)和血管内皮功能的变化。方法测定164例初诊2型糖尿病患者及20例正常人的颈动脉、髂动脉、股动脉的内膜中层厚度,肱动脉反应性充血前后及舌下含服硝酸甘油前后内径的变化,并进行统计学分析。结果糖尿病组IMT较正常对照组增厚(P<0.05);反应性充血时肱动脉内径变化百分率(13.11±6.02)%比正常对照组(16.91±5.97)%明显减弱(P<0.01)。硝酸甘油介导的肱动脉内径变化百分率(16.05±6.98)%与正常对照组(18.12±6.79)%比较差异无统计学意义(P>0.05)。结论应用高分辨率超声检查可较早发现糖尿病患者IMT和血管内皮功能受损情况,对于糖尿病大血管并发症的早期发现及治疗效果的评价具有重要的应用价值。