Predictors of ischemic stroke in non-rheumatic atrial fibrillation

We retrospectively analyzed the clinical features of patients with non-rheumatic atrial fibrillation to identify risk factors of ischemic stroke. Non-rheumatic atrial fibrillation is associated with an increased risk of ischemic stroke. However, the predictors of ischemic stroke in non-rheumatic atrial fibrillation are unclear. The study population consisted of 122 patients with non-rheumatic atrial fibrillation who had no previous clinical cerebral strokes at the start of the follow-up. Patients with cardiomyopathy and paroxysmal or intermittent atrial fibrillation were excluded from the study. The mean age was 61.7+/-12.8 years. We defined two endpoints; namely, occurrence of ischemic stroke (endpoint 1), and ischemic stroke or cardiac death (endpoint 2). During the follow-up, 18 patients had ischemic stroke and 6 patients experienced cardiac death. The 5-year event-free rates for endpoints 1 and 2 were 87.4% and 85.0%, respectively. A Cox analysis revealed that endpoint 1 was significantly associated with age (risk ratio (RR)=1.106, P=0.0052), end-diastolic left ventricular dimension (RR=0.882, P=0.0393), end-systolic left ventricular dimension (RR=1.149, P=0.0323) and the thickness of the interventricular septum (RR=1.493, P=0.0111). Endpoint 2 was associated with age (RR=1.122, P=0.0004), left atrial dimension (RR=1.057, P=0.0666), end-diastolic left ventricular dimension (RR=0.935, P=0.0426), fractional shortening (RR=0.880, P=0.0001) and the thickness of the left ventricular posterior wall (RR=1.644, P=0.0004). The present results suggest that, in addition to left ventricular dimensions and left atrial dimension, left ventricular hypertrophy may be associated with ischemic stroke.