949-102 High Prevalence of Silent Cerebral Infarction in Patients with Lone Atrial Fibrillation

The risk of stroke in patients with lone atrial fibrillation (Af) is low, however, incidence of silent cerebral infarction (SCI) is unclear. To study the risk of SCI in patients with lone Af. 119 patients without history of cerebrovascular accident underwent clinical evaluation, ECG, 20 and M mode Echo/Dopplercardiography. and brain magnetic resonance imaging (Tl, T2. and P). 79 patients (57 male, 22 female; 40 continuous. 39 paroxysmal; age. 62.4±1.0, mean±SE) were determined as a group of lone Af. None of these patients had received anticoagulant or antiplatelet therapy. Left ventricular wall motion were within normal range (%FS: 38±5.5%) and no significant valvular regurgitaion were observed. SCI were detected in 88% of patients (age 50’: 77%,60’: 96%.70’: 100%). There was no significant difference in the prevalence of SCI between paroxysmal and continuous Af. The average number of infarcted foci was 31.1±5.5 (range: 0 to 193) per patient. Locations of infarcted foci were in the white-matter 164%). the deep white-matter (95%). basal ganglion (70%). thalamus (11%). brain stem 19%) and cerebellum (2%1·ConclusionsSCI is quite common in patients with lone Af. Anticoagulant or antiplatelet therapy may be necessary to prevent SCI