Atrial fibrillation characteristics in patients with ischaemic stroke.

BACKGROUND Atrial fibrillation (AF) is a common arrhythmia and an important risk factor for ischaemic stroke (IS). AIM To assess the frequency of AF, including paroxysmal (pxAF), persistent (psAF) and permanent AF (pmAF), in patients hospitalised due to IS as well as to establish the natural course of AF and IS prognosis. METHODS A prospective, non-interventional study of consecutive acute stroke patients with AF with a 6-month follow-up. A favourable stroke outcome was defined when a patient survived or had no disabling stroke during follow-up. RESULTS Within 24 months of recruitment, 838 patients were hospitalised due to IS or transient ischaemic attack. Concomitant AF was diagnosed in 200 (24.4%) of these patients. Permanent AF was observed in 108 (54%), pxAF in 70 (35%), psAF in 9 (4.5%), and AF of unknown duration in 13 (6.5%) patients. Mean age, demographics and concomitant treatment did not differ significantly among groups. The pxAF patients had less often a disabling stroke on admission (81 and 91 vs. 50%, p <0.001) and discharge (55 and 31 vs. 19%, p <0.001) than pmAF and psAF patients, respectively. In-hospital (13 and 9 vs. 3%, p <0.001) and 6-month mortality rates (35 and 40 vs. 14%, p <0.001) were also significantly higher in pmAF and psAF patients than in the pxAF group. Lack of chronic anticoagulation tended to be a risk factor for death (OR 2.1, 95% CI 0.8-5.1, p=0.09). In 20 (66%) patients with pxAF who experienced recurrence of spontaneous AF during hospitalisation, a successful pharmacological cardioversion was performed, whereas in 10 (34%) patients sinus rhythm was not restored. Restoration of sinus rhythm was a risk factor for unfavourable stroke outcome in the 6-month observation period (OR 2.14; 95% CI 1.07-4.29; p=0.03). During the study 29 (40%) patients with pxAF experienced at least one AF recurrence, and 20 (29%) developed psAF. Transformation of psAF to pmAF was observed in 8 (36%) patients. Disabling stroke on admission was a risk factor (OR 4.5, 95% CI 0.9-22.9, p=0.05) for transformation of pxAF to pmAF. CONCLUSION Atrial fibrillation was present in 24.4% of acute IS patients. Paroxysmal AF was diagnosed in 35%, pmAF in 54% and psAF in 11% of patients. During follow-up 29% of pxAF progressed to psAF and 36% psAF to pmAF. In-hospital and 6-month mortality rates and the number of patients with disabling stroke were significantly lower in pxAF than in pmAF and psAF patients. A trend towards unfavourable outcome was observed among patients not receiving chronic anticoagulation.