Abstract 9461: Prevalence and Characteristics of Spontaneous and Adenosine-Induced Acute PV Reconnection Associated With IV Corticosteroid Use During Pulmonary Vein Isolation

Abstract

Background: Atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) is associated with PV to left atrium re-conduction. Intraprocedural corticosteroids may limit RF-induced tissue edema and prevent post-ablation inflammatory responses. We prospectively evaluated the impact of pre-ablation IV corticosteroids on the prevalence of spontaneous and adenosine-induced acute PV reconnection following PVI and on long-term success rates after ablation. Methods: Prior to wide circumferential PVI 45 patients received a single IV bolus of 250 mg of hydrocortisone immediately following transseptal access (steroid group), whereas another 45 consecutive patients underwent standard PVI without IV hydrocortisone (non-steroid group). Post PVI, acute PV reconnection was systematically assessed in each PV (prevalence and location) using a circular mapping catheter during a 20-min waiting period (spontaneous PV reconnection), followed by provocation with IV adenosine (dormant conduction). All patients were followed at 3, 6, and 12 months. Results: Spontaneous PV reconnection during the 20-min waiting period was observed in 9% of PVs (31/358), with no significant difference between the 2 groups (5.5% steroid vs 11.4% non-steroid; p=0.10). Dormant conduction was unmasked in a significantly higher proportion of PVs in the steroid group when compared to the non-steroid group (32.8% of PVs [60/183] vs. 21.1% of PVs [37/175] P=0.03). On multivariate GEE analysis, steroid use remained independently associated with dormant PV conduction (P=0.03). There was no difference in the segmental distribution of reconnection between the two groups. The one-year freedom from recurrent AF did not differ between groups (P=0.37). Radiofrequency time was significantly longer in the steroid group (58±21 vs. 48±18 minutes, P=0.006), whereas procedure duration and fluoroscopy time were comparable (p=0.55, and p=0.44). Conclusions: A single bolus of hydrocortisone 250 mg IV prior to PVI results in greater RF requirements for PV isolation and higher prevalence of dormant PV conduction unmasked by adenosine without affecting long-term outcomes. The utility of these approaches requires evaluation in a long-term prospective randomized study.