Background and purpose: Not only clinical factors, including the CHADS(2) score, but also echocardiographic findings have been reported to be useful for predicting the risk of ischemic stroke in patients with nonvalvular atrial fibrillation (NVAF). However, it remains to be determined which of these factors might be more relevant for evaluation of the risk of stroke in each patient.
Methods: In 490 patients with NVAF who underwent transesophageal echocardiography (TEE), we examined the long-term incidence of ischemic stroke events (mean follow-up time, 5.7±3.3 years). For each patient, the predictive values of gender, the CHADS(2) risk factors (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, history of cerebral ischemia), the CHADS(2) score, and the findings on echocardiography, including TEE risk markers, were assessed.
Results: The ischemic stroke rate was significantly correlated with the CHADS(2) score (p<0.05). According to the results of univariate analyses, age ≥75 years, history of cerebral ischemia, CHADS(2) score ≥2, and presence of TEE risk were significantly correlated with the incidence of ischemic stroke. Cox proportional hazards regression analyses identified age ≥75 years and presence of TEE risk as significant predictors of subsequent ischemic stroke events in patients with NVAF. As compared with that in persons below 75 years of age without TEE risk, the ischemic stroke rate was significantly higher in persons who were ≥75 years of age with TEE risk (4.3 vs. 0.56%/year, adjusted hazard ratio=8.94, p<0.001).
Conclusions: TEE findings might be more relevant predictors of ischemic stroke than the CHADS(2) score in patients with NVAF. The stroke risk was more than 8-fold higher in patients aged ≥75 years with TEE risk.
Keywords: atrial fibrillation; risk; stroke; transesophageal echocardiography.