Steroids may help prevent post-ablation AF recurrence
MedWire News: Short-term, low-dose corticosteroid therapy may be a useful adjunct to catheter ablation for atrial fibrillation (AF), offering a reduction in both short- and medium-term AF recurrence, a clinical study suggests.
The research was undertaken by a Japanese team and tested the value of corticosteroid administration in patients undergoing pulmonary vein isolation (PVI) for paroxysmal AF.
There is much evidence of a mechanistic link between inflammatory processes and the development of AF, explain Takashi Koyama (University of Tsukuba, Japan) and co-authors. Yet, to date, no study has examined the hypothesis that corticosteroids given after PVI might negate AF recurrence by preventing the post-ablation inflammatory response.
To investigate, the team recruited 125 patients with paroxysmal treatment-refractory AF and randomly assigned them to receive intravenous hydrocortisone 2 mg/kg immediately after the procedure plus oral prednisolone 0.5 mg/kg/day for 3 days post-procedure, or a placebo.
Writing in the Journal of the American College of Cardiology, Koyama et al report that body temperature and C-reactive protein levels - both indicative of inflammatory processes - were significantly lower in the corticosteroid group than in the placebo group in the 3 days following ablation.
In the placebo group, body temperature during the initial 3 days was significantly higher in patients with an immediate recurrence of AF than in other participants. By contrast, in the steroid group there was no difference in body temperature between patients with and without an immediate recurrence.
When comparing AF recurrence between treatment and placebo groups, the rate was significantly lower in the corticosteroid group up to 3 days after the procedure (7% vs 31%) but similar in each group between 4 and 30 days post-procedure (20% vs 18%). Between day 31 and 14 months, the rate was again significantly lower in the corticosteroid group (15% vs 29%).
Kaplan-Meier survival analysis confirmed that the rate of freedom from AF without antiarrhythmic drugs was significantly greater with corticosteroids than with placebo; in multivariate analysis, corticosteroid therapy was an independent predictor of AF recurrence, at a hazard ratio of 0.46.
The authors conclude: "Corticosteroid treatment administered shortly after PVI might halt the relationship between inflammation and rapid atrial arrhythmia formation, which may represent a vicious cycle."
In an accompanying editorial, Bernard Belhassen (Tel Aviv Sourasky Medical Center, Israel) said the study offers "the first objective evidence that the immediate atrial tachyarrhythmias occurring during the first 3 days after AF ablation are due to an inflammatory response and can be decreased by a short course of corticosteroid therapy."
However, he admitted that the question of whether corticosteroid therapy should now be used in routine clinical practice or whether to wait for confirmatory studies "is difficult to answer."
MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a trading division of Springer Healthcare Limited. © Springer Healthcare Ltd; 2010
By Joanna Lyford