Abstract 2739: Cardioembolic Stroke Is Frequent in the Late Recurrence After Transient Ischemic Attack

Abstract

Background The high risk of stroke after transient ischemic attack (TIA) has been widely recognized, although the differences of clinical characteristics between early and late recurrent stroke were not well-known. Materials and methods The subjects were 133 consecutive ischemic stroke patients who were admitted to our hospital within one week of onset, and had previously diagnosed as “definite TIA” by trained stroke neurologists. They were divided into five groups according to the interval between prior TIA and subsequent stroke; (1) within 48 hours, (2) 48 hours to 1 week, (3) 1 week to 1 month, (4) 1 month to 3 months, and (5) after 3 months (group 1 to 5, respectively). Then, we compared clinical characteristics and prognosis between the patients who presented recurrent stroke within and after 1 week subsequent to TIA (early recurrence group and late recurrence group, respectively). Results Of the 133 acute stroke patients (mean age 69.9 years, male 66.9%), 46 (34.9%) were in group 1, 28 (21.2%) in group 2, 23 (17.4%) in group 3, 18 (13.6%) in group 4, and 17 (12.9%) in group 5. As to stroke subtypes, most of the non-cardioembolic strokes were frequently observed shortly after TIA, while the percentage of cardioembolism remained high even the time from prior TIA passed ( Figure ). The prevalence of atrial fibrillation (Af) was higher (39.7% vs. 21.3%, P =0.034), and dyslipidemia was lower (41.4% vs. 64.0%, P =0.014) in the late recurrence group than in the early recurrence group. The percentages of patients with hypertension, diabetes mellitus, and higher ABCD 2 score (≥3 or ≥5) were similar in both groups. Among 42 patients with Af, 14 (33.3%) were premorbid, 16 (38.1%) were diagnosed when TIA presented, and 12(28.6%) were diagnosed when stroke presented. In the late recurrence group, 37/58 patients (63.8%) had a poor outcome (modified Rankin Scale ≥3) at 3 month of stroke onset, significantly higher than the 29/75 (38.7%) patients in the early recurrence group ( P =0.005). Conclusions The frequency of cardioembolic stroke dose not decline during the time course after TIA, while most of the non-cardioembolic stroke recur early after TIA. This might be responsible for the poorer functional outcome in late recurrent stroke. More than quarter of Af patients had been asymptomatic before stroke, which suggests the need for repeated examinations to detect Af in patients with TIA of unknown etiology.