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1.
Occult coronary artery disease often accompanies symptomatic peripheral vascular disease and has an important effect on survival. Most perioperative and late fatalities after peripheral vascular operations are due to cardiac causes. Noninvasive cardiac testing can identify patients at increased risk for postoperative cardiac complications, although controversy exists regarding the optimal preoperative evaluation. Risk reduction strategies for patients known to be at high risk are also controversial. Some authors advocate coronary revascularization with coronary artery bypass grafting or percutaneous transluminal coronary angioplasty before the vascular procedure. Others believe that the combined morbidity and mortality of 2 operations exceed those of a peripheral vascular operation performed with aggressive monitoring and medical therapy. Continuous electrocardiographic monitoring after an operation has identified silent myocardial ischemia as a powerful predictor of cardiac complications. Ongoing research is likely to provide insights into the pathogenesis of postoperative cardiac complications and may lead to specific therapeutic interventions. Few prospective studies have been done in this area, and the threshold for preoperative and postoperative intervention is unknown. I review the literature and present an algorithm to guide cardiac testing and risk reduction in patients undergoing elective vascular surgical procedures.  相似文献   

2.
B A Kingwell 《FASEB journal》2000,14(12):1685-1696
Accumulating data suggest that nitric oxide (NO) is important for both coronary and peripheral hemodynamic control and metabolic regulation during exercise. Although still controversial, NO of endothelial origin may potentiate exercise-induced hyperemia. Mechanisms of release include both acetylcholine derived from the neuromuscular junction and elevation in vascular shear stress. A splice variant of neuronal nitric oxide synthase (NOS), nNOSmu, is expressed in human skeletal muscle. In addition to being a potential modulator of blood flow, NO from skeletal muscle regulates muscle contraction and metabolism. In particular, recent human data indicate that NO plays a role in muscle glucose uptake during exercise independently of blood flow. Exercise training in healthy individuals elevates NO bioavailability through a variety of mechanisms including increased NOS enzyme expression and activity. Such adaptations likely contribute to increased exercise capacity and cardiovascular protection. Cardiovascular risk factors including hypercholesterolemia, hypertension, diabetes, and smoking as well as established disease are associated with impairment of the various NO systems. Given that NO is an important signaling mechanism during exercise, such impairment may contribute to limitations in exercise capacity through inadequate coronary or peripheral perfusion and via metabolic effects. Exercise training in individuals with elevated cardiovascular risk or established disease can increase NO bioavailability and may represent an important mechanism by which exercise training conveys benefit in the setting of secondary prevention.  相似文献   

3.
Severe peripheral vascular disease has traditionally precluded the use of free-tissue transfer for lower extremity salvage. In the present series, 10 microvascular transfers performed over a 2-year period are critically evaluated. Vascular surgical consultation was obtained if the preoperative assessment revealed reconstructible vascular disease proximal to the offending wound. Flaps were performed for osteomyelitis in two cases and neurotrophic ulcers in eight cases. Seven of the 10 extremities had prior distal revascularization procedures before the tissue-transfer procedure. There were no anastomotic flap failures; however, one lower extremity underwent below-knee amputation due to sepsis and its cardiovascular sequelae. In properly selected peripheral vascular disease patients, limb salvage can be effected with microsurgical free-tissue transfer. The technique appears invaluable in those patients who have undergone prior contralateral amputation.  相似文献   

4.
Coronary collateral vessels serve as a natural protective mechanism to provide coronary flow to ischemic myocardium secondary to critical coronary artery stenosis. The innate collateral circulation of the normal human heart is typically minimal and considerable variability occurs in extent of collateralization in coronary artery disease patients. A well-developed collateral circulation has been documented to exert protective effects upon myocardial perfusion, contractile function, infarct size, and electrocardiographic abnormalities. Thus therapeutic augmentation of collateral vessel development and/or functional adaptations in collateral and collateral-dependent arteries to reduce resistance into the ischemic myocardium represent a desirable goal in the management of coronary artery disease. Tremendous evidence has provided documentation for the therapeutic benefits of exercise training programs in patients with coronary artery disease (and collateralization); mechanisms that underlie these benefits are numerous and multifaceted, and currently under investigation in multiple laboratories worldwide. The role of enhanced collateralization as a major beneficial contributor has not been fully resolved. This topical review highlights literature that examines the effects of exercise training on collateralization in the diseased heart, as well as effects of exercise training on vascular endothelial and smooth muscle control of regional coronary tone in the collateralized heart. Future directions for research in this area involve further delineation of cellular/molecular mechanisms involved in effects of exercise training on collateralized myocardium, as well as development of novel therapies based on emerging concepts regarding exercise training and coronary artery disease.  相似文献   

5.
Rest pain, tissue loss, and gangrene are manifestations of critical limb ischemia caused by peripheral arterial disease and define a patient subgroup at highest risk for major limb amputation. Patients with nonhealing lower extremity wounds should be screened for the risk factors for peripheral arterial disease and offered noninvasive vascular testing. The diagnosis of critical limb ischemia mandates prompt institution of medical and surgical management to achieve the best chance of limb salvage. Surgical intervention has evolved from primary amputation to open bypass to the present era of endovascular therapy. The goals of surgical bypass and endovascular therapy are to improve perfusion sufficiently to permit healing. Despite poorer patency rates and the more frequent need for reintervention, endovascular therapy has been shown in multiple retrospective studies to achieve limb salvage similar to open bypass. Only one large, prospective, randomized controlled trial exists comparing open bypass with endovascular therapy: The Bypass versus Angioplasty in Severe Limb Ischemia of the Leg (BASIL) trial. Close clinical surveillance and serial monitoring of limb perfusion by means of noninvasive arterial studies are needed to determine the need for further vascular intervention. Limb salvage patients suffer from multiple comorbidities and benefit from a multidisciplinary, team approach to care.  相似文献   

6.
We have pooled data from a series of our exercise training studies undertaken in groups with a broad range of vascular (dys) function to the examine the hypothesis that exercise-induced improvements in the conduit and/or resistance vessel function are related to improvements in risk factors for cardiovascular (CV) disease. Endothelium-dependent and -independent conduit vessel function were assessed by using wall tracking of high-resolution ultrasound images of the brachial artery response to flow-mediated dilation (FMD) and glyceryl trinitrate. Resistance vessel function was assessed using intrabrachial administration of acetylcholine (ACh), sodium nitroprusside, and NG-monomethyl-l-arginine. Randomized cross-over studies of 8-wk exercise training were undertaken in untreated hypercholesterolemic (n = 11), treated hypercholesterolemic (n = 11), coronary artery disease (n = 10), chronic heart failure (n = 12), Type 2 diabetic (n = 15), and healthy control subjects (n = 16). Exercise training did not significantly alter plasma lipids, blood pressure, blood glucose, waist-to-hip ratio, or body mass index values, despite significant improvement in both FMD and ACh responses. There were no correlations between changes in any risk factor variables and indexes of either resistance or conduit vessel function. We conclude that, in these subjects with antecedent vascular dysfunction, the beneficial effects of relatively short-term exercise training on vascular function are not solely mediated by the effects of exercise on CV risk factors.  相似文献   

7.
Diabetes mellitus (DM) is associated with a number of complications of which chronic vascular complications are undoubtedly the most complex and significant consequence. With a significant impact on health care, 50–80% of people with diabetes die of cardiovascular disease (including coronary artery disease, stroke, peripheral vascular disease and other vascular disease), making it the major cause of morbidity and mortality in diabetic patients. A healthy lifestyle is essential in the management of DM, especially the inclusion of aerobic exercise, which has been shown effective in reducing the deleterious effects in vasculature. Interest in exercise studies has increased significantly with promising results that demonstrate a future for investigation. Considering the importance of this emerging field, the aim of this mini-review is to summarize and integrate animal studies investigating physiological mechanisms of vascular dysfunction and remodeling in type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) and how these are influenced by chronic aerobic exercise training.  相似文献   

8.
There are compelling reasons for cardiologists to undertake a more global approach to patients with peripheral vascular diseases: atherosclerosis is a 'systemic' disease frequently causing both coronary and peripheral vascular problems in the same patient; coronary artery disease is the most common cause of morbidity and mortality in patients with peripheral vascular disease; and peripheral vascular disease negatively impacts the management of angina pectoris and congestive heart failure. There are four major areas of special interest to the cardiologist: (1) iliac arteries (vascular access), (2) renal arteries (hypertension and volume overload), (3) subclavian arteries (coronary steal with a left internal mammary artery [LIMA] graft), and (4) carotid arteries (stroke). Technical skills necessary to perform coronary angioplasty are transferable to the peripheral vasculature. However, an understanding of the natural history of peripheral disease, patient and lesion selection criteria, and knowledge of other treatment alternatives are essential to performing these procedures safely and effectively. Appropriate preparation and training, and a team approach, including an experienced vascular surgeon, are both desirable and necessary before interventional cardiologists who are inexperienced in the treatment of peripheral vascular disease attempt percutaneous peripheral angioplasty. There are inherent advantages for patients when the cardiologist performing the procedure is also a clinician. Judgments regarding the indications, timing, and risk/benefit ratio of procedures are enhanced by a long-term relationship between physician and patient. Finally, in view of the increased incidence of coronary artery disease in patients with atherosclerotic peripheral vascular disease, the participation of a cardiologist in their care seems appropriate.  相似文献   

9.
Exercise training improves vascular function in subjects with cardiovascular disease and risk factors, but there is mounting evidence these vascular adaptations may be vessel bed specific. We have therefore examined the hypothesis that exercise-induced improvements in conduit vessel function are related to changes in resistance vessel function. Endothelium-dependent and -independent conduit vessel function were assessed by using wall-tracking of high-resolution brachial artery ultrasound images of the response to flow-mediated dilation (FMD) and nitroglycerine [glyceryl trinitrate (GTN)] administration. Resistance vessel endothelium-dependent and -independent function were assessed using intrabrachial administration of acetylcholine (ACh) and nitroprusside (SNP). Randomized crossover studies of 8-wk exercise training were undertaken in untreated hypercholesterolemic (n = 10), treated hypercholesterolemic (n = 10), coronary artery disease (n = 8), and Type 2 diabetic subjects (n = 15). Exercise training significantly enhanced responses to ACh (P < 0.05) and FMD (P < 0.0001). There were no significant changes in either SNP or GTN responses. The correlation between ACh and FMD responses at entry was not significant (r = 0.186; P = 0.231), and training-induced changes in the ACh did not correlate with those in FMD (r = -0.022; P = 0.890). Similarly, no correlation was evident between the SNP and GTN responses at entry (r = -0.010; P = 0.951) or between changes in these variables with training (r = -0.211; P = 0.191). We conclude that, although short-term exercise training improves endothelium-dependent nitric oxide-mediated vascular function in both conduit and resistance vessels, the magnitude of these improvements are unrelated.  相似文献   

10.
Advances in free-tissue transfer have allowed for lower limb salvage in patients with significant peripheral vascular disease and limb-threatening soft-tissue wounds. The authors retrospectively reviewed their 10-year experience with free flaps for limb salvage in patients with peripheral vascular disease to assess postoperative complication rates and long-term functional outcome. They identified all patients undergoing free-tissue transfer with significant peripheral vascular disease and otherwise unreconstructible soft-tissue defects. Charts were reviewed for perioperative and long-term outcome. Parameters studied included perioperative morbidity and mortality, flap success, bypass graft patency, ambulatory results, and long-term limb and patient survival. Survival data were analyzed using life-table analysis, Kaplan-Meier survival analysis, and Cox testing. A total of 79 flaps were examined in 75 patients with peripheral vascular disease from July of 1990 to November of 1999. All patients would have required a major amputation had free-tissue transfer not been performed. Mean age was 60 years, average hospital stay was 32 days, and perioperative mortality was 5 percent. Within the first 30 days after operation, there were four cases of primary flap loss, and another two were lost as the result of bypass graft failure (8 percent); five of these cases resulted in amputation. There were no primary flap failures after 30 days. Follow-up ranged to 91 months (mean, 24 months). During this time, another 14 limbs were lost, most commonly because of progressive gangrene and/or infection in sites remote from the still-viable free flap. Using Kaplan-Meier survival analysis, 5-year flap survival was 77 percent, limb salvage 63 percent, and patient survival 67 percent. Sixty-six percent of patients were able to ambulate independently with the use of their reconstructed limb at least 1 year after hospital discharge, although some of these later went on to amputation. Free-tissue transfer for lower extremity reconstruction can be performed with acceptable morbidity and mortality in patients with peripheral vascular disease. Flap loss is low, and limb salvage, ambulation, and long-term survival rates in these patients are excellent.  相似文献   

11.
Aim of the study was to determine the potential of Duke Treadmill Score (DTS) in prioritizing patients for coronary angiography in a transitional country clinical setting. We analyzed 114patients with suspected stable coronary artery disease who underwent exercise treadmill testing, and coronary angiography in Slavonski Brod General Hospital. DTS was calculated from treadmill test as: exercise time--(5 x ST deviation in mm)--(4 x exercise angina). Regarding the score, patients were grouped into three groups of risk for coronary artery disease: low risk, medium risk, and high risk patients. All patients underwent coronary angiography, and were grouped in accordance to the severity of the coronary artery disease into three groups: insignificant, significant, or severe coronary artery disease. All patients scored as high risk DTS had significant or severe coronary artery disease. Medium and low risk DTS patients had insignificant coronary artery disease in 50%, and 90% of cases, respectively. Medium risk patients with significant or severe coronary artery disease were significantly older, and had more frequent history of typical chest pain with higher number of episodes per week (P<0.05), whereas there were no differences regarding gender or presence of risk factors. There were no significant differences among medium risk patients regarding the severity of coronary artery disease in exercise time or ST deviation. However, the presence of limiting exercise angina in medium risk patients was significantly more related with significant and severe coronary artery disease (P<0.05). High risk DTS result showed great potential in stratifying patients for immediate coronary angiography. This scoring system may be used in prioritizing patients for coronary angiography in a transitional clinical setting.  相似文献   

12.
Short-term exercise training has been shown to improve cardiovascular function, whereas long-term effects of a physically active lifestyle, on coronary artery function in particular, are still not well studied. We explored possible relationships between physical exercise capacity and coronary and peripheral vascular function in healthy young adults. Twenty-nine healthy young male and female volunteers participated in the study. They underwent 1) basic clinical and echocardiographic characterization, 2) coronary flow velocity reserve (CFVR) measurement of the left anterior descending coronary artery (LAD), 3) common carotid artery (CCA) intima-media thickness (IMT) measurement, 4) assessment of CCA stiffness index (SI), 5) forearm flow-mediated vasodilation (FMD), and 6) submaximal exercise test. The calculated weight-adjusted maximal oxygen uptake capacity (Vo(2 max)(c)) was positively correlated to LAD CFVR and inversely correlated to IMT and SI. Also, subjects with high compared with moderate exercise capacity had higher FMD. In addition, subjects with LAD CFVR in the upper median had greater ratios between endothelium-dependent and -independent vasodilation in the forearm and lower SI in CCA. High exercise capacity due to a physically active lifestyle is associated with high coronary and peripheral artery function, indicating an early protective role of physical exercise for cardiovascular health.  相似文献   

13.
Comprehensive cardiac rehabilitation is more than exercise training for patients with coronary artery disease and now includes all aspects of secondary prevention. Exercise training is individually prescribed based on clinical status and therapeutic goals. Smoking cessation and abstinence and the treatment of hypercholesterolemia are integral to the rehabilitation process. Education and counseling are important adjuncts to treatment, especially soon after a coronary event. Vocational rehabilitation can be included simply and effectively in the rehabilitation process. Efficient and cost-effective cardiac rehabilitation is tailored to a patient''s medical condition, risk factor evaluation, and vocational status. The future of cardiac rehabilitation will be linked to the success of training nonphysician health professionals to provide preventive services.  相似文献   

14.
It is well established that endothelial dysfunction is present in coronary artery disease (CAD), although few studies have determined the effect of training on peripheral conduit vessel function in patients with CAD. A randomized, crossover design determined the effect of 8 wk of predominantly lower limb, combined aerobic and resistance training, in 10 patients with treated CAD. Endothelium-dependent dilation of the brachial artery was determined, by using high-resolution vascular ultrasonography, from flow-mediated vasodilation (FMD) after ischemia. Endothelium-independent vasodilation was measured after administration of glyceryl trinitrate (GTN). Baseline function was compared with that of 10 control subjects. Compared with matched healthy control subjects, FMD and GTN responses were significantly impaired in the untrained CAD patients [3.0 +/- 0.8 (SE) vs. 5.8 +/- 0.8% and 14.5 +/- 1.9 vs. 20.4 +/- 1.5%, respectively; both P < 0.05]. Training significantly improved FMD in the CAD patients (from 3.0 +/- 0.8 to 5.7 +/- 1.1%; P < 0.05) but not responsiveness to GTN (14.5 +/- 1.9 vs. 12.1 +/- 1.4%; P = not significant). Exercise training improves endothelium-dependent conduit vessel dilation in subjects with CAD, and the effect, evident in the brachial artery, appears to be generalized rather than limited to vessels of exercising muscle beds. These results provide evidence for the benefit of exercise training, as an adjunct to routine therapy, in patients with a history of CAD.  相似文献   

15.
Although ventricular tachycardia is a well-known complication of myocardial ischaemia and may be provoked by exercise, many patients may appreciate only the angina and be unaware of the unduly rapid heart rate that precipitates it. Exercise testing is needed to show this arrhythmia and to enable treatment to be started.Twenty-three patients were found to have chronic ischaemic heart disease complicated by ventricular tachycardia. Six patients with old myocardial infarction had ventricular tachycardia at rest which required conversion to sinus rhythm; 17 patients developed ventricular tachycardia only when they exercised. In 12 of these 17 patients coronary angiography showed disease of the anterior descending branch of the left coronary artery; other vessels were usually also affected. Although beta-adrenergic blocking drugs increased exercise tolerance, ventricular tachycardia still occurred when the heart rate on exercise reached a level similar to that before treatment. In five patients coronary artery bypass surgery was performed because of angina and exercise-induced ventricular tachycardia. Exercise tolerance was increased in all three patients who underwent exercise tests after operation, and in two of these patients, both of whom were known to have patent grafts, ventricular tachycardia was abolished.If part of the beneficial effect of coronary bypass surgery is preventing life-threatening ventricular arrhythmias it is essential to detect these, and ambulatory monitoring and stress testing have a complementary role.  相似文献   

16.
目的:探讨运动康复训练对冠心病多支病变患者活动耐量及血脂的影响。方法:选取冠心病多支病变患者,所有患者均进行不完全血运重建术,分为运动康复训练组及对照组,运动康复训练组自术后第三日起治疗组进行运动康复训练,对照组对运动量无要求。3月后,测量两组患者血脂水平及6分钟步行试验,比较两组患者步行距离、心绞痛发作次数、运动至心绞痛出现时间、6分钟内累积运动时间及血脂水平。结果:经运动康复训练治疗3月后,治疗组6分钟步行距离、运动至心绞痛出现时间及运动累积时间较对照组均明显增加,发生心绞痛次数较对照组明显减少。运动康复训练组治疗后甘油三酯、总胆固醇及低密度脂蛋白水平较治疗前明显降低,对照组仅总胆固醇有所降低,甘油三酯及低密度脂蛋白水平较治疗前无统计学差异。结论:运动康复训练可减少冠心病多支病变患者心绞痛发作次数,增加患者运动耐量并调节血脂代谢。  相似文献   

17.
Physical activity, exercise training, and fitness are associated with decreased cardiovascular risk. In the context that a risk factor "gap" exists in the explanation for the beneficial effects of exercise on cardiovascular disease, it has recently been proposed that exercise generates hemodynamic stimuli which exert direct effects on the vasculature that are antiatherogenic. In this review we briefly introduce some of the in vitro and in vivo evidence relating exercise hemodynamic modulation and vascular adaptation. In vitro data clearly demonstrate the importance of shear stress as a potential mechanism underlying vascular adaptations associated with exercise. Supporting this is in vivo human data demonstrating that exercise-mediated shear stress induces localized impacts on arterial function and diameter. Emerging evidence suggests that exercise-related changes in hemodynamic stimuli other than shear stress may also be associated with arterial remodeling. Taken together, in vitro and in vivo data strongly imply that hemodynamic influences combine to orchestrate a response to exercise and training that regulates wall stress and peripheral vascular resistance and contributes to the antiatherogenic impacts of physical activity, fitness, and training.  相似文献   

18.
目的:观察个体化康复运动训练联合八段锦运动对冠心病患者经皮冠状动脉介入术(PCI)术后心功能、心境状态和生活质量的影响。方法:选取2017年9月-2018年9月期间来我院接受治疗的100例冠心病PCI术后患者,根据随机数字表法分为对照组和研究组,各50例。对照组患者在常规治疗的基础上接受个体化康复运动训练,研究组患者在对照组的基础上联合八段锦运动。观察两组心功能、生活质量和心境状态变化情况。统计两组6个月内心血管不良事件发生率。结果:干预后,两组患者6 min步行试验(6MWT)距离、左心室射血分数(LVEF)均较干预前升高,且研究组的变化程度优于对照组(P<0.05)。干预后,两组患者紧张-焦虑、抑郁-沮丧、愤怒-敌意、疲乏-迟钝、迷惑-混乱评分均较干预前下降,精力-活力、与自我有关的情绪评分较干预前升高,且研究组的变化程度优于对照组(P<0.05)。研究组6个月内的心血管不良事件发生率低于对照组,但是两组组间对比无统计学差异(P>0.05)。干预后,两组总体/精神健康、精力、情感/生理职能、躯体疼痛、生理/社会功能各维度评分升高,且研究组较对照组高(P<0.05)。结论:八段锦运动联合个体化康复运动训练可促进冠心病PCI术后患者心功能、生活质量和心境状态改善,同时还可控制心血管不良事件发生风险。  相似文献   

19.
Oxidative capacity and uncoupling protein-3 (UCP3) content are reduced in limb muscles of patients with chronic obstructive pulmonary disease (COPD). It has been hypothesized that the physiological role of UCP3 is to protect mitochondria against lipotoxicity in cases where fatty acid influx exceeds the capacity to oxidize them. Exercise training improves oxidative capacity and reduces UCP3 protein content in healthy subjects, but the response of UCP3 to training in COPD is unknown. We studied the effect of exercise training on UCP3 content in limb muscles of COPD patients. For this, seven healthy age-matched subjects and thirteen patients with COPD were studied. All patients were admitted to an 8-wk exercise training intervention. Exercise capacity was assessed by means of an incremental cycle ergometry test. Biopsies were taken from the vastus lateralis in which UCP3 and lipid peroxidation levels were determined by Western blotting. Citrate synthase and 3-hydroxyacyl-CoA dehydrogenase (HAD; an enzyme involved in fatty acid oxidation) were measured as indexes of muscle oxidative capacity. UCP3 in COPD was approximately 50% lower compared with healthy age-matched controls. In COPD, training induced upregulation of UCP3 [from 67.7 (SD 41.8) to 113.8 (SD 104.2) arbitrary units (AU), P = 0.062], especially in the patients who showed no increase in HAD activity [from 80.9 (SD 52.6) to 167.9 (SD 109.1) AU, P = 0.028], whereas lipid peroxidation levels remained unaltered. We conclude that exercise-training can restore muscle UCP3 protein level in COPD, and the nature of this response complies with the hypothesis that UCP3 may protect against lipotoxicity.  相似文献   

20.
目的:冠状动脉钙化在介入治疗中经常能碰到并且能影响治疗的效果。踝臂指数(ABI)是一种简单易行的无创检查,可作为判断下肢周围动脉疾病(PAD)的良好的无创指标,而且可以预测心血管事件。本课题主要探讨踝臂指数(ABI)对冠状动脉钙化病变的预测价值。方法:100例确诊为冠心病的患者,其中男性70例,女性30例,对所有患者测量ABI及常规生化检查,再行血管内超声虚拟组织学(IVUS-VH)测量冠脉钙化,将冠脉钙化分为三组,比较组间ABI差异,再分析ABI与冠状动脉钙化的相关性。结果:按照不同冠脉钙化分组ABI有显著性差异(P<0.05),ABI>1.3与冠状动脉钙化存在相关性。结论:ABI>1.3对冠状动脉钙化病变的严重程度有预测价值;ABI与冠状动脉钙化病变呈相关性,可作为对冠心病患者危险分层评估的一项指标。  相似文献   

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