Left atrial appendage filling defects restricted to the early phase of cardiac computed tomography is significantly associated with ischemic stroke.

Purpose: To investigate the relationship between filling defects in the left atrial appendage restricted to the early phase of cardiac computed tomography (CCT), and ischemic stroke in patients with atrial fibrillation (AF).

Materials And Methods: A total of 152 patients with non-valvular AF were retrospectively enrolled and divided into two groups according to the stroke history, as confirmed by brain computed tomography (CT) or magnetic resonance imaging (MRI), as the non-stroke group (n = 89) and stroke group (n = 63), respectively. The numbers of patients with filling defects in the early phase of CCT images without thrombi were recorded. Morphological parameters of the LAA were measured for all participants. All patients with early-phase filling defects (n = 44) were assigned to two groups according to ischemic stroke history: the filling defects with stroke group (n = 28) and the filling defects without stroke group (n = 16). The clinical characteristics and LAA morphological parameters were compared.

Results: Univariate analysis showed that compared with the non-stroke group，LAA volume index and age were higher in the stroke group, and the ratio of early phase filling defect in LAA, hypertension and diabetes were also higher, in the meanwhile the LVEF and BMI were lower (P < 0.05).After adjusting confounding factors by the multivariate logistic regression analysis, filling defect was significantly related with stroke [odds ratio (OR): 4.339, 95% confidence interval (CI): 1.951-9.653, P = 0.000]. LAA morphological parameters were not significantly different between the filling defects with stroke group and the group without stroke.

Conclusion: AF patients with LAA non-thrombotic filling defects in the early-phase of CCT had an increased risk of ischemic stroke compared to those without filling defects. This finding may help to optimize stroke risk stratification in patients with AF.