Yan Pei, Shaojie Xu, Haotian Yang, Zhongyuan Ren, Weilun Meng, Yixing Zheng, Rong Guo, Shuang Li, Dongdong Zhao, Kai Tang, Hailing Li, and Yawei Xu
Abstract Background Accumulated evidence has indicated that a high‐normal FT4 level is an independent risk factor for the clinical progression of AF. However, the association between elevated FT4 concentration within the normal range and AF recurrence after cryoballoon ablation in China is unknown. Methods This retrospective and observational study included 453 AF patients who underwent cryoballoon ablation from January 2016 to August 2018. Patients were classified into quartiles based on preprocedural serum FT4 concentration. The clinical characteristics of the patients and the long‐term rate of AF recurrence after ablation were assessed. Results After a mean follow‐up period of 17.4 ± 9.0 months, 91 (20.1%) patients suffered from AF recurrence. The AF recurrence rate by FT4 quartile was 17.7%, 19.0%, 21.4%, and 22.3% for participants with FT4 in quartile 1, 2, 3, and 4, respectively (p