Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

When atrial fibrillation (AF) complicates rheumatic heart disease, the risk of stroke is 17 times that of patients in sinus rhythm and full anticoagulation is mandatory. Non-rheumatic AF carries a lower risk--5% per annum, a 5-fold increase. Four major trials (SPAF, AFASAK, BAATAF, CAFA) have lately examined thromboembolic prophylaxis in this group of patients. These randomized prospective open studies showed a 56-86% reduction in stroke and systemic embolism in patients receiving full anticoagulation compared with placebo. In older people, the BAATAF trial of low-dose warfarin (INR = 1.5-2.7) showed an 86% reduction in stroke and a significant reduction in mortality. In all 4 studies the incidence of hemorrhagic complication was very low (0.5%). In SPAF trial, aspirin, 325 mg/day was found to be effective, but this was not the case in AFASAK, which used 75 mg/day and had an older population. In a double-blind randomized trial indobufene, 100 mg bid, was found effective in the 67% reduction of stroke, systemic and pulmonary embolism in patients with various cardiac diseases in AF or in sinus rhythm. Consequently, a reasonable policy would be to give full or low-dose anticoagulation to those patients with chronic AF who have structural heart disease or are over 65 years old; to consider low-dose anticoagulation or aspirin or indobufene in younger patients with chronic lone AF; and to give indobufene or aspirin or nothing to those with episodes of paroxysmal AF lasting hours only. In borderline cases, the use of transesophageal echocardiography to exclude left atrial thrombus and spontaneous echo contrast may aid decision-making.
 ...
PMID:[Atrial fibrillation: embolic risk and prevention]. 802 31

There is a demonstrated statistical association between atrial fibrillation, rheumatic valvular disease, and embolic stroke. This article assesses the results of 6 major clinical trials (AFASAK, BAATAF, SPINAF, SPAF [parts I and II], CAFA and EAFTA--see text for trial names). Multivariate analysis revealed 4 independent clinical features that identified patients with atrial fibrillation at an increased risk for stroke: hypertension, increasing age, previous transient ischemic attack, and diabetes mellitus. Without anticoagulation therapy, patients with any of these risk factors had a 4% annual risk of stroke. Patients with cardiac disorders such as congestive heart failure and coronary artery disease have a stroke rate 3 times higher than patients without any risk factors; patients with atrial fibrillation but no concomitant risk factors or structural heart disease seemed to have little concomitant risk for stroke. Meta-analysis revealed a 64% reduction of risk for stroke in patients treated with warfarin, as compared with placebo. The value of warfarin therapy in patients > 75 years old is less clear because of a high risk of hemorrhagic complications.
 ...
PMID:Atrial fibrillation, anticoagulation, and stroke. 860 90

Atrial fibrillation belongs to the group of cardiovascular diseases that most frequently predispose to arterial thromboembolic events. Within the last years, the AFASAK, BAATAF, SPAF I, SPINAF, and CAFA trials have consistently demonstrated a significant, approximately 70%, risk reduction for stroke on oral anticoagulation in patients with nonrheumatic atrial fibrillation. This benefit by far outweighed the slight increase in annual major hemorrhage. Recently, additional trials (SPAF II, EAFT, SPAF III, and others) have shed further light on important questions concerning risk factors, secondary prophylaxis, the optimal intensity of anticoagulation, and the role of aspirin and other antiplatelet drugs. The main results of these studies are discussed in this review. The majority of patients with atrial fibrillation are > 65 years of age and have other clinical or echocardiographic risk factors. In these patients, adjusted-dose warfarin with target international normalized ratios (INRs) 2.0 to 3.0 is effective and safe. The risk of stroke rises with INR values < 2.0, whereas INR values > 3.0 result in an increase in intracerebral hemorrhages, especially in the very elderly. In contrast, no anticoagulation seems warranted in younger atrial fibrillation patients < 60 years of age without any clinical or echocardiographic risk factor. An overview of all randomized trials that compared aspirin with placebo and/or adjusted-dose warfarin indicates that adjusted-dose warfarin is approximately 50% more effective than aspirin for primary and secondary prevention of stroke, at least in patients with atrial fibrillation who have clinical risk factors. Therefore, oral anticoagulation clearly is the therapy of choice for prevention of thromboembolism in patients with atrial fibrillation.
 ...
PMID:Role of anticoagulant therapy in atrial fibrillation. 972 82

Atrial fibrillation, which has age-dependent exponentially rising high prevalence, is now well known to frequently predispose to systemic thromboembolism. In the past decade, several large-scale clinical randomized trials for prevention of thromboembolism in nonrheumatic atrial fibrillation have been performed for its primary and secondary preventions. The first five major trials (AFASAK, BAATAF, SPAF-I, CAFA, SPINAF) for primary prevention of stroke have demonstrated a significant risk reduction (68%) for stroke on oral anticoagulation without any significant increase in major hemorrhage. On the other hand, although AFASAK and SPAF I showed controversial results for comparison of aspirin and control, the collaborative analysis revealed a significant risk reduction (36%). In their analysis of risk factors for stroke, prior stroke, diabetes mellitus, and hypertension have been stressed as high risk factors. Recently, some additional trials have been done concerning secondary prophylaxis, primary prevention in high risk patients, the optimal dose of warfarin, the role of aspirin and so on. In EAFT, a secondary prevention trial, warfarin has reduced (66%) stroke from 12%/yr to 4%/yr, while aspirin alone to 10%/yr. In SPAF III, it has been reported that adjusted-dose warfarin with target INR2.0 to 3.0 is effective and safe in high risk patients. However, SPAF II showed that warfarin was not useful in elder patients (75yr <) because of an increase in hemorrhage. That may be why warfarin was still underused (40% >). Anyway, it is of importance to think about the strategy for prevention on the individual level of patients with atrial fibrillation, taking into consideration echocardiographical and hematological data besides clinical risk factors.
 ...
PMID:[Frontiers in prevention of thromboembolism in nonvalvular atrial fibrillation]. 1034 39