ATHENS, GREECE. Radiofrequency ablation, not surprisingly, causes significant inflammation of heart tissue which, in turn, increases the likelihood of experiencing tachyarrhythmias (atrial fibrillation, atrial flutter or inappropriate sinus tachycardia) during the 3- to 6-month period following the ablation. Arrhythmia recurrence during this early follow-up period is strongly associated with long-term failure. Early recurrence can be suppressed by the administration of corticosteroids (cortisone). However, these powerful drugs have several unwanted side effects that preclude their mid-term or long-term use in post-ablation patients, especially if they suffer from hypertension, or coronary or structural heart disease.

A group of Greek researchers now report that the post-procedure administration of colchicine, a powerful anti-inflammatory, markedly reduces the incidence of early recurrence, and also causes a significant drop in the inflammatory markers C-reactive protein (CRP) and interleukin-6 (IL-6). Colchicine was isolated from the herb autumn crocus in 1820 and has since been used primarily in the treatment of gout and rheumatism. The main side effects of colchicine are nausea and gastrointestinal upset. However, in large doses it is highly toxic and is absolutely contraindicated in patients with impaired kidney function.

The clinical trial of colchicine for the prevention of atrial fibrillation (AF) recurrence involved 160 patients who had undergone anatomically-guided radiofrequency catheter ablation for paroxysmal AF. The average age of the group was 62 years and 71% were male. Average left atrial diameter was 44 mm and average left atrial ejection fraction was 55%. The incidence of hypertension, diabetes, coronary artery disease, and heart failure in the group was 38%, 26%, 34%, and 24% respectively.

Following the ablation procedure (average duration of 3 hours) study participants were randomly assigned to receive either placebo or 0.5 mg twice daily of colchicine. No antiarrhythmics were allowed during the 3-month trial period. As expected, the levels of CRP and IL-6 were elevated on the day following the procedure in both groups. However, whilst levels in the placebo group remained high at day four, they had dropped by 35% and 19% respectively in the colchicine group. During the 3-month follow-up arrhythmia recurred in 27 (33.5%) of 80 patients in the placebo group compared with only 13 (16%) of 81 patients in the colchicine group – a risk reduction of 68%.

Seven (8.6%) of the colchicine group reported diarrhea versus only 1.3% in the placebo group. No serious adverse events were reported. High CRP and IL-6 levels were strongly associated with increased recurrence risk. The researchers conclude that colchicine is an effective and safe treatment for prevention of early arrhythmia recurrence following pulmonary vein isolation, in the absence of antiarrhythmic drug treatment.
Deftereos, S, et al. Colchicine for prevention of early atrial fibrillation recurrence after pulmonary vein isolation. Journal of the American College of Cardiology, Vol. 60, No. 18, October 30, 2012, pp. 1790-96

Editor's comment: The association between post-ablation inflammation and an increased risk of early AF recurrence is well known. Our post-ablation care protocol cautions against vigorous physical activity in the early recovery period and suggests the use of natural anti-inflammatories such as curcumin, Zyflamend, fish oil, beta-sitosterol and Boswellia.