Objectives:This study aimed to elucidate the incidence,clinical characteristics and prognosis of ST-elevation during radiofrequency catheter ablation for atrial fibrillation(AF). Methods:Consecutive patients who underwent radiofrequency catheter ablation for AF in Tongren Municipal People's Hospital,Qixingguan District People's Hospital of Bijie City and Guizhou Provincial People's Hospital from January 2021 to August 2023 were enrolled in this study.All patients underwent CARTO three-dimensional electroanatomical mapping and radiofrequency ablation via atrial septal approach under local anesthesia.The ST-elevation of electrocardiogram was analyzed.Follow-up was performed at 1,3,6,and 12 months after radiofrequency ablation.AF recurrence and duration,use of antiarrhythmic drugs,and incidence of death,thromboembolism,bleeding,and perioperative complications were evaluated. Results:ST-elevation was observed in 5 out of 798 patients(0.62%).ST-elevation occurred after transseptal puncture in three patients and during PentaRay multielectrode mapping in two patients.Blood pressure was significantly increased in three patients with transient ST-elevation(<20 min)and hemodynamic collapse occurred in two patients with persistent ST-elevation(>20 min).Catheter ablation of AF was completed in 4 patients,1 patient suffered severe hemodynamic disorders during radiofrequency catheter ablation,and the procedure was stopped immediately,this patient died from multiple organ system failure on the fifth day after failed radiofrequency catheter ablation,and the other 4 patients had no perioperative complications.The mean follow-up was(6±3)months,only 1 patient developed short atrial tachycardia,and the other patients had no recurrent atrial fibrillation and palpitation. Conclusions:Transient or persistent ST elevation can occur in patients during AF ablation.Early detection and rapid management are needed to prevent severe hemodynamic instability and cardiogenic death.