To give clinicians “the most up-to-date evidence-based recommendations for the prevention of ischemic stroke among survivors of ischemic stroke or transient ischemic attack,” the American Heart Association and American Stroke Association published updated guidelines online Oct. 21 in the journal Stroke.

The new guidelines, intended to help clinicians select preventive therapies for individual patients, have been endorsed by the American Academy of Neurology as an educational tool for neurologists. The American Association of Neurological Surgeons and the Congress of Neurological Surgeons have affirmed their educational content as well.

“Since the last update [in 2006], we’ve had results from several studies testing different interventions. We need to reevaluate the science every few years to optimize prevention,” Dr. Karen L. Furie, chair of the 18-member writing committee and director of the stroke service at Massachusetts General Hospital, Boston, said in a statement accompanying the updated guidelines.

Approximately one-fourth of the nearly 800,000 strokes that occur each year in the United States are recurrences in patients who have already had a stroke or TIA, Dr. Furie and her colleagues noted (Stroke 2010 Oct. 21 [doi:10.1161/STR.0b013e3181f7d043]).

New recommendations in the guidelines cover control of risk factors, interventions for atherosclerotic disease, antithrombotic therapies for cardioembolism, and use of antiplatelet drugs for noncardioembolic stroke.

Controlling Risk Factors

While the clinical usefulness of screening patients for the metabolic syndrome remains controversial, the guidelines advise that if patients are already diagnosed as having the disorder, they should be counseled to improve their diet, exercise, and lose weight to reduce their stroke risk. The individual components of the metabolic syndrome that raise the risk of stroke – particularly dyslipidemia and hypertension – should be treated. Survivors of TIA or stroke who have diabetes should follow existing treatment guidelines for glycemic control and blood pressure management.

Interventions for Atherosclerotic Disease

The writing committee recommended that patients with stenosis of the carotid artery or vertebral artery should receive optimal medical therapy, including antiplatelet drugs, statins, and risk factor modification. In patients whose TIA or stroke was due to 50%-99% stenosis of a major intracranial artery, they advised prescribing aspirin therapy (50-325 mg daily) over warfarin. Long-term maintenance of blood pressure at less than 140/90 mm Hg and total cholesterol at less than 200 mg/dL “may be reasonable,” they wrote. The usefulness of angioplasty, with or without stent placement, for an intracranial artery stenosis is not yet known in this population and is considered investigational. Extracranial-intracranial bypass surgery is not recommended.

For patients with atherosclerotic ischemic stroke or TIA who do not have coronary heart disease, the committee stated that “it is reasonable to target a reduction of at least 50% in LDL-C or a target LDL-C level of less than 70 mg/dL.”

Antithrombotics for Cardio- and Noncardioembolic Stroke

The guidelines recommend that patients who need anticoagulation therapy but cannot take oral anticoagulants should be given aspirin alone. They warn that the combination of aspirin plus clopidogrel “carries a risk of bleeding similar to that of warfarin and therefore is not recommended for patients with a hemorrhagic contraindication to warfarin.”

Any temporary interruption to anticoagulation therapy in patients who have atrial fibrillation and are otherwise at high risk for stroke calls for the use of bridging therapy with subcutaneous administration of low-molecular-weight heparin, according to the guidelines.

Dr. Furie and the committee members recommended caution in using warfarin in patients who have cardiomyopathy characterized by systolic dysfunction (a left ventricular ejection fraction of 35% or less) because of a lack of proven benefit.

Evidence is also insufficient to establish whether anticoagulation therapy is better than aspirin therapy for secondary stroke prevention in patients who have a patent foramen ovale.

The guidelines also address secondary stroke prevention under a variety of special circumstances, such as cases of arterial dissection, hyperhomocysteinemia, hypercoagulable states, and sickle cell disease. They also detail management specific to women, particularly concerning pregnancy and the use of postmenopausal hormone replacement.

Dr. Furie reported receiving research grants from the U.S. National Institute of Neurological Disorders and Stroke as well as the ASA-Bugher Foundation Center for Stroke Prevention Research. Some of her 17 coauthors disclosed receiving research support from, being a speaker for, or consulting to or sitting on an advisory board for, companies that manufacture drugs commonly prescribed for stroke prevention.

The guidelines can be obtained at the American Heart Association and American Stroke Association website, www.americanheart.org.

Copyright (c) 2010 Elsevier Global Medical News. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

10月21日，美国心脏学会和美国卒中学会在《卒中》(Stroke)杂志上在线发表了新版卒中复发预防指南，目的是向临床医生“提供关于如何预防缺血性卒中或一过性脑缺血发作(TIA)幸存者缺血性卒中复发的最新循证建议”。

 

新版指南是由18名专家组成的编写委员会制定，由美国波士顿麻省总医院卒中服务中心主任Karen L. Furie博士担任编写委员会主席。新版指南旨在帮助临床医生针对个体患者选择恰当的预防性治疗措施，现已获得美国神经病学会的认可，将作为神经科医生的教材。美国神经外科医师协会和神经外科医师大会也将该指南列为其教育内容。

 

新版指南涵盖了卒中复发预防的方方面面，包括危险因素的控制、动脉粥样硬化性疾病的干预措施、心源性脑栓塞的抗血栓治疗以及非心源性卒中患者抗血小板药物的使用等等。

 

控制危险因素

 

新版指南给出的建议是：如果患者已经确诊患有代谢综合征，则应告知其如何改善饮食方案、加强锻炼并减轻体重以降低卒中风险。对于可能导致卒中风险增加的代谢综合征各组成成分，尤其是血脂异常和高血压，则应予以相应的治疗。对于患有糖尿病的TIA或卒中幸存者，应遵循现行的血糖控制和血压管理指南。

 

动脉粥样硬化性疾病的干预措施

 

编写委员会建议，颈动脉或椎动脉狭窄患者应接受最佳的内科治疗，包括抗血小板药物、他汀类药物以及危险因素的控制。对于因颅内大动脉狭窄50%~99%致TIA或卒中的患者，则建议采用阿司匹林(50~325 mg/日)而非华法林。血压应长期维持在140/90 mmHg以下，总胆固醇则应维持在200 mg/dl以下。对于这类人群，血管成形术加或不加支架置入术的临床效果尚不清楚，不建议采用颅外-颅内动脉旁路术。对于没有冠心病的动脉粥样硬化性缺血性卒中或TIA患者，委员会建议“将LDL-C的控制目标定为下降50%或低于70 mg/dl。”

 

心源性和非心源性卒中的抗血栓治疗

 

指南建议，对于需要接受抗凝治疗但又不能服用口服抗凝剂的患者，应只采用阿司匹林。阿司匹林与氯吡格雷联用“可能导致与华法林类似的出血风险，因此不适用于存在华法林出血性禁忌证的患者。”

 

对于暂时中断了抗凝治疗因而存在卒中高风险的房颤患者，建议采用桥接治疗，即皮下注射低分子量肝素。对于患有以收缩功能障碍(左室射血分数≤35%)为特征的心肌病的患者，应慎用华法林。对于患有卵圆孔未闭的患者的卒中二级预防，现有证据尚不足以确定抗凝治疗是否就优于阿司匹林治疗。

 

新版指南还讨论了各种特殊情况下的卒中二级预防，比如动脉夹层、高同型半胱氨酸血症、高凝状态以及镰状细胞病等病例。指南还详细介绍了一些针对女性患者的特殊管理方案，尤其是妊娠期患者的管理以及绝经后激素替代治疗的使用。

 

研究者声明接受多以医学机构和医药企业的经济资助。

 

新版指南可参见美国心脏学会和美国卒中学会的网站www.americanheart.org。

 

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