Measurement of subclinical carotid atherosclerosis may help in predicting risk for stroke in patients with diabetes

Diabetes is one of the most important risk factor for stroke and cardiovascular disease (CVD), especially in young patients. The control of classical vascular risk factors failed in terms of prevention of stroke in patients with diabetes. In addiction, in these patients the glycemic control showed a benefit on microvascular disease but lacked an established benefit in macrovascular disease. Therefore, implementations of effective stroke prevention strategies appear necessary in patients with diabetes. Ultrasound surrogate or intermediate markers of carotid atherosclerosis include carotid intima-media thickness (cIMT), carotid plaque (CP), and carotid stiffness (STIFF) have been demonstrated to increase in patients with diabetes and to be able to predict risk for stroke. In this editorial we discuss the opportunity to prevent the onset of vascular disease in their “preclinical or subclinical” stage in patients with higher risk for stroke such as diabetic patients.     

Stroke prevention in the elderly

The incidence of stroke and risk factors peak in subjects > or = 75 years. Highest risk patients benefit most from effective therapy. For this reason, all strategies of proven value in stroke prevention must be assiduously applied. Control of hypertension, hyperlipidemia, diabetes mellitus and cessation of cigarette smoking are obligatory at all ages but are of special importance in the elderly. Antithrombotic drugs have been proven beneficial for patients at high risk. Lower risk subjects, including those with asymptomatic carotid artery disease, gain no proven benefit from anti-platelet drugs. Patients with non-valvular atrial fibrillation (NVAF), a condition that increases with age, require anticoagulant therapy. Strict regulation of the INR is required otherwise aspirin is recommended. Without evidence of organ failure, elderly patients with severely stenotic symptomatic carotid artery disease should receive endarterectomy. They benefit most. The evidence for benefit from endarterectomy in asymptomatic subjects at any age is weak and cannot be recommended.     

STROKE PREVENTION IN THE ELDERLY

The incidence of stroke and risk factors peak in subjects ≥75 years. Highest risk patients benefit most from effective therapy. For this reason, all strategies of proven value in stroke prevention must be assiduously applied. Control of hypertension, hyperlipidemia, diabetes mellitus and cessation of cigarette smoking are obligatory at all ages but are of special importance in the elderly.

Antithrombotic drugs have been proven beneficial for patients at high risk. Lower risk subjects, including those with asymptomatic carotid artery disease, gain no proven benefit from anti-platelet drugs. Patients with non-valvular atrial fibrillation (NVAF), a condition that increases with age, require anticoagulant therapy. Strict regulation of the INR is required otherwise aspirin is recommended.

Without evidence of organ failure, elderly patients with severely stenotic symptomatic carotid artery disease should receive endarterectomy. They benefit most. The evidence for benefit from endarterectomy in asymptomatic subjects at any age is weak and cannot be recommended.     

Carotid artery involvement in patients of atherosclerotic coronary artery disease undergoing coronary artery bypass grafting

BACKGROUND: Patients with concomitant critical carotid and coronary artery disease are at risk of major neurological events while undergoing coronary artery bypass grafting. The presence of carotid artery stenosis increases the stroke rate in the perioperative period. In an effort to reduce the stroke rate, many institutions perform routine preoperative noninvasive assessment of the carotid arteries. METHODS AND RESULTS: We analyzed the clinical and laboratory data of 1,200 patients who underwent coronary artery bypass surgery in the last 2 years. Carotid Doppler was normal in 186 patients (15.5%), and showed <30% stenosis in 796 (66.3%), 30%-50% in 110 (9.2%), 50%-70% stenosis in 64 (5.3%) and critical (>70%) stenosis in 44 (3.7%) patients. Conventional risk factors such as hypercholesterolemia, hypertension, smoking and family history were not independent predictors of carotid artery stenosis. However, diabetes as a risk factor had a significant association with carotid artery disease (79.6% v. 43.8%, p<0.02). There was a trend towards increased prevalence of carotid artery stenosis in patients with > or = 2 risk factors (84.3% v. 68.8%). Patients with significant carotid artery stenosis had severe coronary artery disease (triple-vessel disease 93.3%, left main coronary artery disease 12.0%). Out of 44 patients with critical carotid artery stenosis, 27 were subjected to carotid angiography. Doppler findings correlated well with angiography. Seventeen patients underwent carotid artery intervention. None had any perioperative neurological events. A total of 5 (0.4%) patients had a major stroke. Coronary artery bypass grafting was done in 27 patients with critical stenosis without any intervention. The stroke rate (11.1%) was higher in these patients compared to patients with < 70% carotid artery disease or post-carotid intervention (2.5%) patients. Thus, untreated >70% carotid artery stenosis was associated with a higher stroke rate. CONCLUSIONS: Doppler screening of the carotid artery is helpful in detecting the subgroup of patients at increased risk of stroke. Patients with critical carotid artery stenosis should be subjected to angiography. Prophylactic intervention may reduce the occurrence of stroke in the perioperative period.     

Statin therapy and stroke prevention

Hypercholesterolemia has not traditionally been considered an important risk factor in the pathogenesis of stroke. However, recent studies show that statin therapy significantly reduces ischemic stroke for patients with established coronary artery disease. Statin therapy may reduce stroke through amelioration of precerebral atherosclerosis in the carotid artery and the aorta. Anti-atherosclerotic, anti-inflammatory, and antithrombotic actions of statins occur within the blood and in plaque. Statins may also protect against cerebral ischemia through beneficial modulation of the brain endothelial nitric oxide system. Ongoing studies are exploring the role of statin therapy in the primary prevention of stroke and in the prevention of cognitive decline and multi-infarct cerebrovascular disease.     

Carotid artery intervention

Atherosclerotic carotid artery disease is a major contributor to the incidence of stroke, particularly in the elderly. Atherosclerosis is a systemic illness and patients often present with multisystem involvement of several vascular beds including coronary, cerebral, and peripheral vascular territories. The majority of strokes related to carotid artery disease are embolic in nature, not occlusive. Non-invasive screening tests including ultrasound, CT angiography and MR angiography are helpful in identifying pathology. However, the gold standard, for diagnosis and treatment allocation remains invasive angiography. Medical therapy to reduce the risk of stroke includes antiplatelet agents, primarily aspirin in doses of 81 mg to 325 mg per day. Control of blood pressure and the use of statin therapy is effective in reducing the incidence of stroke. Carotid endarterectomy is more effective for preventing stroke in symptomatic (transient ischemic attack or stroke) patients with = or >50% diameter stenosis and asymptomatic patients with = or >60% diameter stenosis, than aspirin therapy. In patients at increased risk for surgical complications during stroke prevention surgery (carotid endarterectomy), carotid stents have been shown to be as good or better than surgery at improving outcomes.     

Management of Combined Severe Carotid and Coronary Artery Disease

Patients with severe carotid and coronary disease—especially if they require coronary artery bypass grafting (CABG)—are at high risk of cardiac events and stroke. Carotid revascularization should be considered for patients with symptomatic carotid disease and bilateral severe asymptomatic carotid stenosis. In patients with unilateral asymptomatic carotid stenosis, decision to proceed to revascularization should be based more on a perspective of long-term stroke prevention than of perioperative stroke reduction. Compared with endarterectomy, carotid artery stenting is associated with a lower incidence of periprocedural myocardial infarction, an event linked to long-term mortality. This observation may be particularly relevant for patients with advanced coronary artery disease such as those undergoing CABG. Irrespective of the carotid revascularization strategy, a broad disease management approach based on lifestyle modification and pharmacologic cardiovascular prevention is more likely to affect both the quality and duration of life than revascularization itself.     

Stroke prevention in women: Challenges and opportunities

Women have a 20% lifetime risk of stroke. In addition, the majority of stroke-related deaths occur in women. Reducing the burden of stroke in women through prevention would positively affect public health. Unfortunately, most of the data used to develop specific evidence-based guidelines for stroke prevention in women were derived from coronary heart disease studies. Stroke was a secondary and less common outcome, if it was included at all. In addition, women have traditionally been underrepresented in stroke prevention trial cohorts. Stroke prevention in women offers many challenges, not only related to data extrapolated from clinical trials primarily composed of men, but also because physicians may underestimate cardiovascular risk in women, and therefore prevention strategies may not be appropriately undertaken. The opportunities to improve stroke prevention in women include increasing patient and physician awareness of risk and optimizing management of key modifiable risk factors (eg, hypertension, hyperlipidemia, physical inactivity, obesity, and diabetes).     

冠状动脉钙化的研究进展

冠状动脉钙化是冠状动脉粥样硬化患者不良预后的危险因素。多种因素与冠状动脉钙化的发生和发展相关,包括性别、年龄、持续的炎症状态、高血压、高脂血症和糖尿病等,近年来人们越来越关注非传统高危因素,以期为冠状动脉钙化的一级预防开辟新的思路。不断发展的影像学技术也为冠状动脉钙化的早期发现和发生机制的研究提供了很好的帮助。文章将重点回顾冠状动脉钙化的高危因素、发生机制、检查手段、临床意义及其治疗的研究进展,旨在提高人们对冠状动脉钙化的进一步认识和重视水平。     

Hyperglycaemia and its relation to cardiovascular morbidity and mortality: has it been resolved?

Type 2 diabetes is preceded by long-standing asymptomatic hyperglycaemia. This prediabetic state is characterised by elevated post-prandial hyperglycaemia and yet normal fasting plasma glucose (FPG). The relationship between abnormal circulating glucose levels and the development of long-term diabetic complications became apparent 70 years ago, soon after the introduction of insulin and the prevention of early death due to ketoacidosis. The main issues regarding diabetes and the various target organs throughout the cardiovascular system, including coronary artery disease (CAD), peripheral vascular disease (PVD), increased intima-media thickness (IMT) and stroke, are as follows: CAD causes much of the serious morbidity and mortality in patients with diabetes, who have a 2- to 4-fold increased risk of CAD; epidemiological evidence confirms an association between diabetes and increased prevalence of PVD; and diabetes induces increased IMT and stroke by adversely affecting cerebrovascular circulation including the carotid artery, akin to its effects in the coronary and lower extremity vasculature. In diabetes, FPG and HbA(1C) are the main parameters of glucose metabolism used to monitor and control hyperglycaemia. Recently, particular emphasis has been placed on post-prandial plasma glucose as a parameter in the metabolic assessment of diabetic patients. Therefore, while addressing the question of hyperglycaemia and its relation to cardiovascular morbidity and mortality, we have to look for the possible mechanisms by which diabetic hyperglycaemia causes these complications. Then, we must examine the evidence on how the main parameters of glucose metabolism correlate with cardiovascular complications. This review addresses these issues.     

Management of severe bilateral carotid artery stenosis concomitant to severely symptomatic coronary arterial disease requiring coronary artery bypass grafting: a case-based review

Patients with significant carotid disease have an increased risk of stroke during coronary artery bypass grafting (CABG). However, due to its inherent risk and to the variety of mechanisms responsible for postoperative stroke, prophylactic carotid endarterectomy has an uncertain value, particularly in cases of asymptomatic unilateral carotid disease. In addition, the timing and sequence of coronary and carotid surgeries are controversial matters. Prophylactic carotid artery stenting is emerging as a potentially safer strategy. The major limitation of carotid stenting is the need for one month of dual antiplatelet therapy and the potential need to postpone CABG, which is not possible in patients with refractory unstable coronary syndromes. We describe the case of a patient with severe unstable coronary artery disease and bilateral carotid artery disease who was successfully managed with stenting of the most critical coronary lesion, staged bilateral carotid stenting, followed by CABG three weeks later.     

后循环短暂性脑缺血发作患者临床特征及脑卒中危险因素分析

目的探讨后循环短暂性脑缺血发作（transient ischemic attacks,TIA）患者的临床特征及脑卒中危险因素,为预防脑卒中提供依据。 方法选取2010年10月至2013年12月浙江医院收治的确诊的后循环TIA患者88例,对其临床特征及相关危险因素（高血压、冠心病、糖尿病、高脂血症、房颤、吸烟）进行分析。相关性分析采用Logistic回归分析。 结果主要临床特征：年龄多≥60岁（69.3%）,最常见的临床表现为头晕（44.3%）,症状持续时间多在10 min以内（43.2%）,TIA后脑卒中发生相关危险因素中以高血压的发生率最高（48.9%）,椎基底动脉狭窄≥50%者占20.5%。随访7d内脑卒中的发生率为8%（7/88）。对6项危险因素进行Logistic回归分析,结果显示糖尿病为TIA后发生脑卒中的独立危险因素(OR=5.867,95%CI=1.186～29.014,P<0.05)。 结论后循环TIA的临床表现复杂多样,高血压是最常见的危险因素,糖尿病可能对TIA后发生脑卒中的影响更大。     

Cerebrovascular Events After Cardiovascular Procedures: Risk Factors,Recognition, and Prevention Strategies

Stroke has long been a devastating complication of any cardiovascular procedure that unfavorably affects survival and quality of life. Over time, strategies have been developed to substantially reduce the incidence of stroke after traditional cardiovascular procedures such as coronary artery bypass grafting, isolated valve surgery, and carotid endarterectomy. Subsequently, with the advent of minimally invasive technologies including percutaneous coronary intervention, carotid artery stenting, and transcatheter valve therapies, operators were faced with a new host of procedural risk factors, and efforts again turned toward identifying novel ways to reduce the risk of stroke. Fortunately, by understanding the procedural factors unique to these new techniques and applying many of the lessons learned from prior experiences, we are seeing significant improvements in the safety of these new technologies. In this review, the authors: 1) carefully analyze data from different cardiac procedural experiences ranging from traditional open heart surgery to percutaneous coronary intervention and transcatheter valve therapies; 2) explore the unique risk factors for stroke in each of these areas; and 3) describe how these risks can be mitigated with improved patient selection, adjuvant pharmacotherapy, procedural improvements, and novel technological advancements.     

Homocysteine, a risk factor for cardiovascular disease

Fasting hyperhomocysteinemia is an independent risk factor for coronary artery disease, stroke, peripheral vascular atherosclerosis, and for arterial and venous thromboembolism. The risk for cardiovascular disease with homocysteine is similar to conventional risk factors. The interaction of hyperhomocysteinemia with hypertension and smoking is strong and the combined effect is more than multiplicative. The combined effect of homocysteine and cholesterol is additive. Homocysteine produces atherosclerosis, thromboembolism, and vascular endothelial cell injury. Vascular dysfunction produced by homocysteine may be due to endothelial cell damage. Homocysteinemia-induced atherosclerosis is probably due to various factors including endothelial cell injury, inability to sustain S-nitroso-homocysteine formation because of imbalance between production of nitric oxide by dysfunctional endothelium and homocysteine, smooth muscle cell proliferation, and thromboembolism. There is strong evidence that endothelial cell injury is associated with oxidative stress produced by homocysteine. Hyperhomocysteinemia is associated with numerous conditions, including coronary disease, stroke, peripheral vascular disease (carotid artery and cerebrovascular atherosclerosis), venous thrombosis, renal disease, diabetes mellitus, and organ transplant. Folic acid, vitamin B₁₂ and B₆ have been shown to be beneficial in reducing plasma homocysteine levels. Folic acid is specifically very effective, safe and inexpensive.     

糖尿病合并冠心病患者冠状动脉病变与颈动脉超声的关系

目的探讨合并糖尿病的冠心病患者冠状动脉病变与颈动脉病变的关系,分析与冠状动脉病变程度相关的危险因素。方法经冠状动脉造影检查确诊冠心病患者160例,其中76例合并2型糖尿病（糖尿病组）,84例未合并糖尿病（非糖尿病组）,对2组冠状动脉病变及颈动脉超声情况进行对比分析。同时测量收缩压（SBP）、舒张压（DBP）、身高、体质量,计算体质指数,检测空腹血糖、血浆总胆固醇（TC）、三酰甘油（TG）、低密度脂蛋白胆固醇（LDL-C）、高密度脂蛋白胆固醇（HDL-C）等,记录糖尿病病程,分析冠心病合并糖尿病危险因素。结果糖尿病组体质指数、TG均明显高于对照组。HDL-C明显低于对照组（P〈0．05）;糖尿病组冠脉3支病变、弥漫性病变、闭塞性病变比例高,颈动脉内斑块增加（P〈0．05）。结论冠心病合并糖尿病患者冠状动脉病变较不合并糖尿病患者严重,颈动脉斑块增加,颈动脉与冠状动脉硬化程度有明显的相关性。低HDL-C、收缩压、舒张压、高TG、糖尿病病程、年龄是2型糖尿病合并冠心病冠状动脉病变程度的危险因素。     

颈动脉狭窄的病因、病理学和内科治疗

颈动脉狭窄是缺血性卒中的主要病因之一。最近的研究发现,高同型半胱氨酸血症和基质金属蛋白酶及其内源性组织抑制剂在颈动脉狭窄中起重要作用。针对这2种新型危险因素的干预措施在将来缺血性脑血管病的防治中可能有广阔的应用前景。     

Cardiovascular disease in recent onset diabetes mellitus

Diabetes is associated with a marked increased risk of atherosclerotic vascular disorders, including coronary, cerebrovascular, and peripheral artery disease. Cardiovascular disease (CVD) could account for disabilities and high mortality rates in patients with diabetes. Conventional risk factors, including hyperlipidemia, hypertension, smoking, obesity, lack of exercise, and a positive family history, contribute similarly to macrovascular complications in type 2 diabetic patients and non-diabetic subjects. The levels of these factors in diabetic patients are certainly increased, but not enough to explain the exaggerated risk for macrovascular complications in the diabetic population. Furthermore, recently, macrovascular complications of diabetes have been shown to start before the onset of diabetes. Indeed, several clinical studies have confirmed the increased risk of CVD in patients with impaired glucose tolerance (IGT). Since insulin resistance-related postprandial metabolic derangements are thought to play a central role in the development and progression of CVD in patients with IGT, amelioration of postprandial metabolic disturbance is a therapeutic target for the prevention of CVD in these high-risk patients. Therefore, in this paper, we review the molecular mechanisms for the increased risk of CVD in recent onset diabetes mellitus, especially focusing on postprandial dysmetabolism. We also discuss here the potential therapeutic strategies that specially target the mechanisms responsible for vascular alterations in diabetes.     

颈动脉粥样硬化与冠状动脉旁路移植术后神经系统并发症相关性研究

目的:探讨颈动脉粥样硬化程度与非体外循环下冠状动脉旁路移植术后,神经系统并发症的关系。方法:连续选择择期行非体外循环下冠状动脉旁路移植术的患者475例,根据颈动脉超声结果分为四组:无狭窄、轻度、中度及重度狭窄,分析狭窄程度与术后神经系统并发症的关系及影响因素。结果:①四组患者之间年龄、脑卒中病史、糖尿病史及神经系统并发症比较,差异有统计学意义(P<0.05);②颈动脉狭窄患者术后神经系统并发症的发生率高于无颈动脉狭窄患者(χ2=3.851,P=0.050);③脑卒中病史(OR=1.835,95%CI:1.023～3.289,P<0.05)、颈动脉重度狭窄(OR=2.793,95%CI:1.296～6.018,P<0.05)与术后神经系统并发症相关(P<0.05)。结论:脑卒中病史、颈动脉重度狭窄是旁路移植术后神经系统并发症的危险因素。颈动脉不论狭窄程度,均可导致术后神经系统并发症发生率增高,低灌注可能为主要原因。     

Conventional coronary artery bypass grafting in patients with total occlusion of the internal carotid artery

The number of patients with coexisting disease of the coronary and carotid arteries is increasing. Patients with total occlusion of the carotid artery may have a higher risk of stroke during cardiopulmonary bypass surgery and in the perioperative period. We report our results for coronary artery bypass grafting (CABG) in patients with total occlusion of the carotid artery. We examined 269 patients who underwent carotid artery duplex scanning (CADS) before CABG between November 1995 and January 1998. Among them, 11 patients (4.1%) had total occlusion of a carotid artery. Four patients underwent elective CABG and five underwent emergency CABG. One patient underwent anastomosis of the superficial temporal artery to the middle cerebral artery (STMC) and one patient underwent a combined CABG and carotid endoarterectomy (CEA) procedure. A transient neurological event occurred in only one patient (9.1%). The other patients recovered uneventfully. Our results suggest that CABG can be performed without stroke in patients with total unilateral occlusion of a carotid artery using our strategies. Received: April 25, 2001 / Accepted: August 3, 2001     

血浆内皮功能标志物在心脑血管病中的意义

病理状态下,内皮细胞可被激活、出现功能障碍和受损.内皮功能障碍在心脑血管病的发病过程中起着关键作用,并可通过外周血进行检测.von Willebrand因子浓度能预测冠心病和卒中风险;可溶性血栓调节素浓度与冠心病和卒中的预后相关;可溶性细胞间黏附分子-1能预测颈动脉粥样硬化、冠心病、周围动脉病和糖尿病风险;颈动脉粥样硬化、冠心病和糖尿病患者血浆可溶性E-选择素水平升高;内皮素-1水平升高预示发生充血性心力衰竭的风险增高;注射内皮祖细胞有词望成为治疗心脑血管病的一种新手段.