Comparison of two different doses of single bolus steroid injection to prevent atrial fibrillation recurrence after radiofrequency catheter ablation

Purpose: Steroids may play a role in preventing the early recurrence of atrial fibrillation (AF) after radiofrequency catheter ablation (RFCA). However, optimal doses and route of steroid delivery have not yet been determined. This study evaluated the effect of two different doses of a single bolus injection of steroids on AF recurrence after RFCA. Materials and Methods: Of 448 consecutive AF patients who underwent RFCA, a single steroid bolus was injected into 291 patients. A low-dose steroid group (n=113) received 100 mg of hydrocortisone and a moderate-dose steroid group (n=174) received 125 mg of methylprednisolone. We used propensity-score matching to select patients as follows: control (n=95), low-dose (n=95), and moderate-dose steroid groups (n=97). Results: Pericarditis developed in 1 (1.1%) control patient, 2 (2.1%) low-dose patients and 0 moderate-dose patients. Maximum body temperature and C-reactive protein were significantly decreased in the moderate-dose steroid group compared to the other groups (p<0.01). The number of patients of early AF recurrence (≤3 months) did not differ among three groups. Early recurrence was 24 (25%) in the control, 24 (25%) in the low-dose and 25 (26%) in the medium-dose groups (p=0.99). Compared with control group, low-dose or moderate-dose steroid treatment did not effectively decrease mid-term (3‒12 months) AF recurrence [22 (23%) vs. 23 (24%) vs. 18 (19%); p=0.12]. Conclusion: A single injection of moderate-dose steroid decreased inflammation. However, single bolus injections of low-dose or moderate-dose steroids were not effective in preventing immediate, early or midterm AF recurrence after RFCA.