Embolism ischemic stroke

Activase Alteplase, recombinant Genentech Acute myordial infarction, acute massive pulmonary embolism, ischemic stroke... 

Ischemic stroke has numerous causes. Cerebral infarction may result from large artery atherosclerosis, cardiac embolism, small artery lipohyalinosis, cryptogenic embolism, or, more rarely, from other diverse conditions such as arterial dissection, infective endocarditis, and sickle cell disease. Arterial occlusion is the cause of at least 80% of acute cerebral infarctions. " ... 

Cl 0.08-0.96) and symptomatic pulmonary embolism (PE) (OR 0.34, 95% Cl 0.17-0.69), but an increase in major extracranial hemorrhage when compared to placebo (OR 2.17, 95% Cl 1.10. 28). Nonsignificant reductions in combined death and disability, as well as increases in case fatality and sICH were also observed. The authors concluded that insufficient evidence existed to support the routine use of LMWH in the management of patients with ischemic stroke. 

The Heparin in Acute Embolic Stroke Trial (HAEST) was a multicenter, randomized trial of the effect of LMWH (dalteparin 100 lU/kg sc twice daily) or aspirin (160 mg once daily) for the acute treatment of 449 patients with ischemic stroke and atrial fibrillation (AF). The primary outcome was the rate of recurrent stroke within 14 days. No difference in rates of early recurrence (8.5% dalteparin treated vs. 7.5% aspirin treated) or good 3-month functional outcome was found. The frequency of early slCH was 2.7% on dalteparin versus 1.8% on aspirin. 

Kamphuisen PW, Agnelli G. What is the optimal pharmacological prophylaxis for the prevention of deep-vein thrombosis and pulmonary embolism in patients with acute ischemic stroke Thromb Res 2007 119(3) 265-274. 

Carotid artery disease is one of the major causes of ischemic stroke. The predominant mechanisms by which it causes stroke are (a) arterial embolism from atherosclerotic plaques (b) hemodynamic changes, leading to watershed infarcts and (c) distal propagation of thrombus originating from acute carotid occlusion. ... 

Risk factors for embolic cerebrovascular accidents include previous ischemic stroke, transient ischemic attacks (TIA), systemic embolism, age >75 yr, moderately or severely impaired left ventricular systolic function, hypertension, diabetes mellitus... 

Ischemic stroke is the abrupt development of a focal neurologic deficit that occurs due to inadequate blood supply to an area of the brain. Most often, this is due to a thrombotic or embolic arterial occlusion leading to cerebral infarction. 

Ischemic stroke is the abrupt development of a focal neurologic deficit that occurs due to inadequate blood supply to an area of the brain. Most often, this is due to a thrombotic or embolic arterial occlusion leading to cerebral infarction. A thrombotic occlusion occurs when a thrombus forms inside an artery in the brain. An embolism refers to a clot originating outside of the brain in which a piece of the clot breaks loose and is carried to the brain. 

Ischemic strokes account for 88% of all strokes and are due either to local thrombus formation or to emboli that occlude a cerebral artery. Cerebral atherosclerosis is a causative factor in most cases of ischemic stroke, although 30% are of unknown etiology. Emboli can arise either from intra- or extracranial arteries. Twenty percent of embolic strokes arise from the heart. 

Indications Management of acute myocardial infarction (AMI), acute ischemic stroke, and acute massive pulmonary embolism... 

More than 50% of patients with cerebral embolism have atrial fibrillation. In the majority of these patients, the underlying cardiac disease is nonvalvular. The risk of ischemic stroke and atrial fibrillation increases with age, reaching a cumulative risk of 35% during a patient s lifetime. Combined results from several randomized trials show that warfarin reduces the risk of stroke in patients with nonrheumatic atrial fibrillation by 68% (to 1.4% per year), with an excess incidence of major hemorrhage (including intracranial) of only 0.3% per year. 

Alteplase was the first commercially available recombinant tissue-type plasminogen activator (rt-PA) (25), It has a plasma half-life of less than five minutes and is metabolized by the liver, This agent was initially hailed as fibrin-specific unlike its precursors (urokinase and streptokinase). It was thought that this would result in a better safety profile, but this has not been born out in either the coronary or the peripheral experience, where actually there may be a higher bleeding risk as infusion time increases. Alteplase is currently indicated for use in the treatment of myocardial infarction, acute ischemic stroke, and pulmonary embolism. 

Therapeutic uses Currently alteplase is approved for the treatment of myocardial infarction, massive pulmonary embolism, and acute ischemic stroke. Alteplase seems to be superior to streptokinase and urokinase in dissolving older clots, and may ultimately be approved for other applications. Alteplase administered within 3 hours of the onset of ischemic stroke significantly improves clinical outcome, that is, the patients ability to perform activites of daily living. 

Approximately 20% of ischemic stroke is cardioembolic. There are a large number of potential cardiac sources of embolism (Table 6.3) but it may be difficult to be certain whether an identified putative embolic source is the cause of a stroke, particularly if there are alternative causes such as coexistent large artery disease, or if the stroke is lacunar and unlikely to be caused by cardiac embolism. 

About one-fifth of patients with infective endocarditis have an ischemic stroke or TIA as a result of embolism of valvular vegetations. Cerebrovascular symptoms usually occur before the infection has been controlled and may be the presenting feature (Hart et al. 1990 ... 

Penetrating and non-penetrating neck injuries are more likely to damage the carotid than the better protected vertebral artery. The vertebral artery appears to be more vulnerable to rotational and hyperextension injuries of the neck, particularly at the level of the atlas and axis. Laceration, dissection and intimal tears may be complicated by thrombosis and then embolism and, therefore, ischemic stroke at the time of the injury or some days or even weeks after the injury. Later stroke may be a consequence of the formation of a traumatic aneurysm, arteriovenous fistula or a fistula between the carotid and vertebral arteries (Davis and Zimmerman 1983). 

Subarachnoid hemorrhage due to septic embolic infarction in infective endocarditis. Cerebrovascular Diseases 9 182-184 Krespi Y, Akman-Demir G, Poyraz M et al (2001). Cerebral vasculitis and ischemic stroke in Behcet s disease report of one case and review of the literature. European Journal of Neurology 8 719-722... 

Organised inpatient (stroke unit) care for stroke review update. Cochrane Database of Systematic Reviews 1 CD000177 van der Worp HB, Kappelle LJ (1998). Complications of acute ischemic stroke. Cerebrovascular Diseases 8 124-132 Wijdicks EFM, Scott JP (1997). Pulmonary embolism associated with acute stroke. 

As a result of the large randomized controlled trials, it is now clear that endarterectomy of recently symptomatic severe carotid stenosis almost completely abolishes the high risk of ischemic stroke ipsiiaterai to the operated artery over the subsequent two or three years (see Ch. 27 for detailed discussion of the selection of patients for surgery). Moreover, this effect is durable over at least 10 years (European Carotid Surgery Trialists Collaborative Group 1991, 1998 Mayberg et al. 1991 North American Symptomatic Carotid Endarterectomy Trial Collaborators 1991 Barnett et al. 1998 Rothwell et al. 2003). Indeed, the ipsiiaterai stroke risk becomes so low that presumably both embolic and low-flow strokes are being prevented (Fig. 25.1). 

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