Thrombolytic therapy

The accepted role for thrombolytic therapy has until recently been limited because of its complexity and side-effects. It has generally been reserved for use systemically in a limited number of patients with acute, major pulmonary embolism or iliofemoral venous thrombosis, and locally in some patients with acute, peripheral arterial occlusion. Its indications have now been greatly expanded by the confirmation from large, multicentre trials completed within the last year that it is also effective in acute myocardial infarction, with a reduction in acute mortality of 20-25%. Moreover, administration has become greatly simplified as dosage regimens have been standardised and the need for laboratory monitoring eliminated. The standard thrombolytic agent used for nearly 3 decades has been streptokinase but within the last year recombinant, human, tissue-type plasminogen activator (the first 'third generation' thrombolytic agent) has become clinically available. This protein is the body's own chief plasminogen activator and has been produced by recombinant DNA technology. Compared with streptokinase, it appears to be both somewhat more effective and also safer (less bleeding and probably no allergic reactions). Other new thrombolytic agents are also being developed but the cost-effectiveness of the newer agents in relation to streptokinase will be for many the main practical issue.     

Thrombolytic therapy for pulmonary embolism

Pulmonary embolism with choc carries a 25 to 50% mortality rate. Although no large randomized clinical trial is available, some insights of a meta-analysis suggest that thrombolysis decreases the mortality rate in these patients. In patients without clinical evidence of haemodynamic impairment, the mortality rate is much lower and does not justify more aggressive therapy other than anticoagulants. Recent data however suggest that among clinically stable patients, some may have a higher mortality risk. These so called sub-massive or intermediate-risk pulmonary embolism are defined either by right ventricular dysfunction assessed by echocardiography or by elevated troponin or brain natriuretic peptide. The role of thrombolytic treatment in these patients remains controversial. A large randomized controlled trial is underway to resume the debate.     

缺血性脑卒中的溶栓治疗

急性缺血性脑卒中(AIS)又称脑梗死,是由于局部脑血流突然中断引起局部脑组织缺血坏死而致的相应神经功能缺损。它威胁着上千万人的生命,是工业化国家第3死亡原因,仅次于心肌梗死和癌症,同时它也是造成终身残疾的首要原因[1]。在脑卒中发生后脑血管造影显示80%病人有动脉闭塞,如     

Thrombolytic therapy for unstable angina

Thrombolytic therapy for unsTable angina has not gained acceptance as a primary treatment for unsTable angina (UA) despite the evidence showing a reduction in mortality when these agents are given for myocardial infarction. The purpose of this review is to examine the clinical value of thrombolytic therapy for UA. The multiple lines of evidence supporting intracoronary thrombus formation as a key mechanism in the pathogenesis of UA are reviewed. Studies examining the effect of thrombolytic therapy on angiographic endpoints have shown little effect on the extent of luminal narrowing, but do reveal a decrease in angiographically detected thrombus. Twelve randomized, controlled trials of thrombolytic agents in 611 UA patients with predefined clinical endpoints have been published. These trials varied widely in design and adjunctive therapy both in treated and control groups. Review of these trials shows a tendency to fewer clinical events such as death, infarction, and need for revascularization in treated patients, with a corresponding increase in bleeding complications. Clinical efficacy of thrombolytic therapy cannot be excluded by the available data, perhaps in part because of insufficient numbers of patients treated. Determination of the net clinical value of thrombolytic therapy must await larger and more definitive trials.     

Thrombolytic therapy for arterial thrombosis.

The major development in the field of intra-arterial thrombolytic therapy over the past year was the publication of the phase II results of the Thrombolysis or Peripheral Arterial Surgery study, which compared the safety and efficacy of catheter-directed thrombolysis and surgery as the initial treatment of acute arterial occlusion. The results are consistent with those of the prior two studies, showing little or no difference between surgery and thrombolysis in the most important endpoints of survival and amputation rate. Patients receiving thrombolysis needed fewer interventions, but this benefit was balanced by increased bleeding complications. Additional studies have, therefore, been aimed at identifying subsets of patients with acute arterial occlusion who are most likely to benefit from thrombolysis. These studies have refined the selection criteria for use of thrombolytic therapy over the past year. In addition, studies have been published evaluating new drug doses and regimens aimed at broadening the scope of thrombolytic therapy in patients with acute arterial occlusion.     

Thrombolytic therapy for venous thromboembolism.

The role of thrombolytic therapy for venous thromboembolism remains uncertain. To date, no well-designed randomized clinical trial has shown that the benefits of thrombolysis exceed the risks for a well-defined subgroup of patients with acute pulmonary embolism. Recent reports have underscored the risks of thrombolytic therapy. The largest multinational registry of patients in whom acute pulmonary embolism had been diagnosed found that 3% of 311 patients who underwent thrombolysis for acute pulmonary embolism suffered an intracranial hemorrhage. Because of the serious risk associated with systemic thrombolysis, investigators have continued to study methods that rapidly remove venous thromboemboli while minimizing the risk. Reports of catheter fragmentation combined with thrombolysis as well as catheter-directed thrombolysis are promising, but well-designed clinical trials are needed to clarify the utility of these techniques.     

Thrombolytic therapy for deep vein thrombosis

Opinion statement  The incorporation of endovascular interventions into mainstream clinical practice for patients with deep vein thrombosis (DVT) has been changing rapidly as a result of four major trends. First, there now is a much greater appreciation among practicing physicians of the major impact of the postthrombotic syndrome (PTS) on DVT patients’ late quality of life. Second, there have been rapid advances in the methods by which thrombus can be rapidly removed using endovascular techniques, resulting in greater efficiency and treatment safety. Third, these changes together have spurred a major change in recommended DVT treatment paradigms: there is now published expert consensus that adjunctive endovascular DVT thrombolysis should be strongly considered as a first-line treatment strategy for selected patients with extensive acute proximal DVT. Finally, DVT researchers from multiple subspecialties have finally come together in a major multidisciplinary clinical trial project to subject endovascular DVT thrombolysis to the rigorous scientific testing that is needed for clinicians to be confident in its efficacy, safety, and cost-effectiveness as a first-line DVT treatment strategy. Pending the results of this and other studies, medical physicians should routinely inform DVT patients about the long-term consequences of DVT; ensure that they understand the importance of anticoagulant therapy and elastic compression stockings in preventing PTS; provide a balanced discussion of the risks, benefits, and uncertainties associated with endovascular DVT thrombolysis to patients with extensive proximal DVT; and develop collaborative clinical and research relationships with physicians experienced with endovascular DVT therapy.     

急性心肌梗死的溶栓治疗

急性心肌梗死(AMI)是危害人类健康的严重疾病,目前,全球每年有1700万人死于心血管疾病,其中有一半以上死于AMI。我国AMI的发病率呈逐年上升趋势,目前已接近国际水平。近年来,尽管急诊经皮冠状动脉介入治疗(PCI)在AMI的急性期得到了广泛应用,也取得了显著的疗效,但溶栓治疗在世界范围内仍然是应用最广泛的再灌注治疗方法[1]。1溶栓治疗的理论基础AMI是由于冠状动脉易损斑块破裂,继发血栓形成,导致冠脉管腔急性完全性闭塞而引起的。病理研究表明,AMI时冠状动脉内闭塞血栓的发生率高达70%～90%,冠状动脉血栓的形成是冠状动脉内膜损伤…     

心源性脑栓塞的溶栓治疗

在缺血性卒中的各亚型中，心源性脑栓塞（cardiogenic cerebral embolism，CCE）起病急骤，其脑梗死体积较大，神经功能损害通常较重，治疗棘手，预后较差。所谓CCE，是指由来自心脏的脱落栓子阻塞脑供血动脉，从而引起相应供血区脑组织的缺血性坏死，占整个缺血性卒中的20％。以往的治疗原则主要包括对症处理、治疗原发病和使用抗凝药，防止病情进展及再栓塞，但疗效欠佳。很多存活的患者出院时，仍遗留严重语言障碍和肢体瘫痪等。因此，CCE的治疗成为长期困扰临床医师而又亟需解决的问题。     

急性缺血性卒中溶栓治疗

试验状态 :从 2 0 0 3年 10月开始 ,已经募集 3例患者。试验目的 :比较动脉内rtPA溶栓与静脉rtPA溶栓的疗效。试验设计 :多中心剂量开放随机对照试验 ,采用盲法随访。纳入标准 :大脑中动脉 (MCA)缺血性卒中发病 3h内的患者。排除标准 :卒中发病前已有残疾 ,发病时昏迷 ,神经功能缺损迅速改善 ,发病时出现癫 ,对比增强剂过敏 ,分娩期或哺乳期 ,未经控制的高血压 ,颅内出血 ,溶栓治疗的禁忌证或存在其他有可能增加患者危险的任何情况。患者处理 :患者随机分为静脉溶栓组和动脉内溶栓组 ,静脉溶栓组患者 (rtPA 0 9mg/kg ,最大剂量 90mg)…