Cardioembolic stroke is frequent in late recurrence after transient ischemic attack

Abstract

Background: Transient ischemic attack (TIA) is often followed by a stroke episode. Differences between early and late recurrent stroke, however, have not been elucidated.

Methods: We enrolled 133 consecutive patients with acute ischemic stroke who presented to our hospital and had previously been diagnosed with TIA. They were divided into 5 groups according to the interval between TIA and subsequent stroke: <48 hours (group 1); 48 hours to 1 week (group 2); 1 week to 1 month (group 3); 1 month to 3 months (group 4); and >3 months (group 5). Patients who underwent recurrent stroke within and after 1 week subsequent to TIA (the early and late recurrence groups, respectively) were compared with regard to clinical findings.

Results: Of the 133 patients, 46 (34.6%) were in group 1, 29 (21.8%) in group 2, 23 (17.3%) in group 3, 18 (13.5%) in group 4, and 17 (12.8%) in group 5. Most of the noncardioembolic strokes were observed shortly after TIA, while the percentage of cardioembolic stroke remained high even after long post-TIA periods. The prevalence of atrial fibrillation (AF) was higher in the late recurrence group than in the early recurrence group (41.4% v 24.0%, P = .033). Among 42 patients with AF, 12 (28.6%) were newly diagnosed at the time of stroke.

Conclusions: The frequency of cardioembolic stroke did not decline as time after TIA passed. More than one quarter of AF patients had been asymptomatic before stroke, suggesting the need for repeated examinations to detect AF in patients with TIA of unknown etiology.

Keywords: Acute ischemic stroke; atrial fibrillation; cardiac embolism; prognosis; recurrent stroke; transient ischemic attack.