The Effects of Eosinophil on the Left Atrial Thrombus in Patients With Atrial Fibrillation

Background: Atrial fibrillation (AF) is the most common cardiac rhythm disorder. Atrial fibrillation causes a 5-fold increased risk for thromboembolic stroke. It is known that eosinophils play an important role in thrombosis. We aimed to compare the number of eosinophil counts of the patients with and without thrombi in the left atrium (LA) or in the left atrial appendage (LAA) and to ascertain the association of eosinophil counts with the presence of thrombi. Method: The study included 89 patients diagnosed with persistent AF who underwent transesophageal echocardiography and designated to undergo cardioversion. The patients were divided into 2 groups: group 1 consisted of 40 patients (18 male; average age 63.27 ± 1.4) who had thrombus formation in the LA or LAA, and group 2 consisted of 49 patients (23 male; average age 66.53 ± 1.56) who did not have any thrombus in the LA or LAA. These patients underwent concurrent routine biochemical tests and eosinophil count on whole blood count was also performed. Results: Baseline characteristics of the study groups were comparable. Group 1 patients had higher eosinophil and mean platelet volume values than group 2 (233.0 ± 30.7 vs 118.9 ± 11.8 and 9.77 ± 0.20 vs 8.27 ± 0.12 fL, P < .001, respectively). In group 1, the patients’ LA diameter is higher than that in group II. Conclusion: As a result, our study revealed a relationship between eosinophil count and LA thrombus in patients with nonvalvular AF.