Plasma levels of coagulation and fibrinolysis markers in acute ischemic stroke patients with lone atrial fibrillation

Atrial fibrillation (AF) is a well-defined risk factor for ischemic stroke. Patients with lone AF represent a subgroup of AF patients with the lowest lifelong stroke risk. Nonvalvular atrial fibrillation (NVAF) confers a hype rcoagulable state resulting in an increased risk of thromboembolism. This s tudy was performed to determine the contributory role of alteration in the hemostatic markers of thrombin generation and fibrinolysis in patients with lone AF during acute ischemic stroke episode. We studied thrombin-antithro mbin complexes (TAT), prothrombin fragments 1+2 (F1+2), tissue-type plasmin ogen activator (tPA) and plasminogen activator inhibitor type-1 (PAI-1) con centrations in patients with acute middle cerebral artery ischemic stroke d ue to atherosclerotic large artery disease (n=50), lone AF (n=24) and cardi oembolism (n=21). The values were compared with those of age-matched contro l subjects with lone AF and sinus rhythm (n=21 and 15, respectively). The m ean F1+2 concentration was higher in the control subjects with lone AF in c omparison with those without AF (p=0.014). Patients with stroke due to poss ible cardioembolism, from lone AF or other causes, had higher TAT (and marg inally higher F1+2) concentrations than those with atherosclerotic stroke ( p<0.001), tPA concentrations were not different among groups (p=0.89). PAI- I levels were marginally high er in stroke patients with lone AF and athero thrombotic large artery disease compared to the controls without AF (p=0.05 ). These results suggest that in the acute period of ischemic stroke second ary to lone AF, enhancement of the coagulatory activity occurs as a result of increased thrombin generation, similar to other possible sources of card ioembolism. Observed hemostatic alterations in acute ischemic stroke associ ated with lone AF may indicate some therapeutic and prognostic implications .