Anticoagulation therapy stroke

While early CEA is considered to be relatively safe, it may not always be necessary. For instance, early surgery can be deferred in patients who are medically unstable or for those whose cardiac or respiratory status requires optimization. In the NASCET study, the rate of ipsUateral stroke at 1 month for medically treated patients with high-grade stenoses was only 3.3% and was even lower (1.7%) in patients with near-occlusions. Even in patients with free-floating intraluminal thrombus, anticoagulant therapy is a well tolerated and reasonable first step, given... 

Sherman D (2002) Long-term Anticoagulation Therapy in Prevention of Stroke. Curr Treat Options Neurol 4 411-416... 

P-Blockers are the drugs of choice in atrial fibrillation because they decrease heart rate and promote conversion to sinus rhythm. Longterm, low-dose anticoagulant therapy reduces the risk of stroke that Is associated with atriai fibrillation. 

The absolute risk of stroke varies 20-fold among patients with non-valvular atrial fibrillation, depending on age and associated vascular diseases. Estimating an individual s stroke risk is, therefore, essential when considering potentially hazardous anticoagulation therapy. More than 10 similar stroke risk models for patients with atrial fibrillation have been published, but the CHADS2 scheme is now the most widely used. 

Patients in atrial fibrillation who have a TIA or stroke without other clear etiology should be given anticoagulation therapy if there are no contraindications (European Atrial Fibrillation Trial Study Group 1993, 1995). Recent studies have shown that warfarin is as safe as aspirin in elderly patients with atrial fibrillation (Rash et al. 2007 Mant et al. 2007). Patients with presumed cardioembolic TIA or stroke secondary to other causes should certainly receive antithrombotic therapy. Also they may benefit from anticoagulation in certain circumstances, such as intracardiac mural thrombosis after myocardial infarction, although there have been no randomized trials in situations other than non-valvular atrial fibrillation. 

Anticoagulant therapy, chiefly warfarin, and platelet inhibitors, such as aspirin, are used prophylactically to prevent thromboembolic disease while fibrinolytic drugs can be used to destroy thrombi already formed and can be life saving after a myocardial infarction or stroke. 

Nutescu EA, Helgason CM. Concomitant drug, dietary, and lifestyle issues in patients with atrial fibrillation receiving anticoagulation therapy for stroke prophylaxis. Curr Treatment Options Cardiovasc Med 2005 7 241-250. 

In 14 clinical trials of prothrombin complex concentrates for reversal of oral anticoagulation therapy, seven of 460 patients (1.5%) had thrombotic events, three thrombotic strokes, two cases of deep venous thrombosis, and two non-Q-wave myocardial infarctions [31 ]. However, in 40 patients taking oral anticoagulants, who needed cardiopulmonary bypass surgery, and of whom 20 were treated with prothrombin complex concentrates, no thrombotic events occurred [35 ]. 

Cl = 1.7, 10) or antiplatelet therapy alone (OR=2.2 95% Cl = 1.0,9.4) compared with patients therapeutically anticoagulated with warfarin [3. Anticoagulant therapy therefore appears to reduce both the incidence and severity of ischemic stroke. 

INR > 1.7 (PT > 15 if no INR available) with or without chronic oral anticoagulant use Seizure at onset of stroke (This relative contraindication is intended to prevent treatment of patients with a deficit due to postictal Todd s paralysis or with seizure due to some other CNS lesion that precludes thrombolytic therapy. If rapid diagnosis of vascular occlusion can be made, treatment may be given.)... 

Combination Anticoagulant and Antiplatelet Therapy in Acute Stroke... 

This was largely influenced by the high-dose UFH group in 1ST (OR 1.38, 95% Cl 1.05-1.82). An interaction by UFH dose (p = 0.01) on recurrent stroke risk with combination UFH-aspirin therapy compared to aspirin monotherapy was observed, with a trend toward increased risk of recurrent stroke with high-dose UFH + aspirin (OR 1.22, 95% Cl 0.92-1.62) and a trend toward reduced risk with low-dose UFH + aspirin (OR 0.75, 95% Cl 0.56-1.03), equivalent to 10 fewer (95% Cl 0-20 fewer) recurrent strokes per 1000 patients treated. They found a small, but significant beneht of LMWH over aspirin in the prevention of symptomatic DVT, equivalent to 10 (95% Cl 0-30) fewer DVTs per 1000 patients treated. Compared with aspirin, anticoagulants were associated with nonsignificantly fewer symptomatic PEs (OR 0.85, 95% Cl 0.55-1.32). There were fewer PEs with the combination of UEH and aspirin (OR 0.58, 95% Cl 0.34—1.00), equivalent to 5 fewer (Cl 0-10) PEs per 1000 patients treated. However, the overall incidence of symptomatic DVT and PE was low (1.1% and 0.7%). 

Overall no evidence was found to support the claim that anticoagulants offer a net advantage over aspirin in patients with acute ischemic stroke. There was evidence, however, to suggest that combination anticoagulant and aspirin therapy was associated with a small increase in the number of deaths at the end of follow-up, equivalent to 20 more deaths per 1000 patients treated. This adverse effect can probably be attributed partly to the 10 extra sICHs, and the 5 extra major extracranial hemorrhages per 1000 patients treated with combination anticoagulant/ aspirin therapy. 

Warfarin has not been adequately studied in non-cardioembolic stroke, but it is often recommended in patients after antiplatelet agents fail. One small retrospective study suggests that warfarin is better than aspirin.30 More recent clinical trials have not found oral anticoagulation in those patients without atrial fibrillation or carotid stenosis to be better than antiplatelet therapy. In the majority of patients without atrial fibrillation, antiplatelet therapy is recommended over warfarin. In patients with atrial fibrillation, long-term anticoagulation with warfarin is recommended and is effective in both primary and secondary prevention of stroke.12 The goal International Normalized Ratio (INR) for this indication is 2 to 3. 

Alteplase initiated within 3 hours of symptom onset has been shown to reduce the ultimate disability due to ischemic stroke. A head CT scan must be obtained to rule out hemorrhage before beginning therapy. The patient must also meet specific inclusion criteria and no exclusionary criteria (Table 13-2). The dose is 0.9 mg/kg (maximum 90 mg) infused IV over 1 hour after a bolus of 10% of the total dose given over 1 minute. Anticoagulant and... 

---