Intermittent claudication: how should we react to this symptom?

Management (AFFIRM) trial, which may shed indirect light on the merit of use of amiodarone on the grounds of its superior efficacy. On the other hand, a longer duration of follow-up would allow sufficient time for development of amiodarone organ toxicity with its attendant significant costs. The major adverse effects of sotalol and propafenone are predominantly seen early in the treatment course, a time frame that the current study would have captured. The longterm toxicity of amiodarone may result in irreversible organ damage with significant chronic care cost implications. Although surveillance testing for amiodarone toxicity was accounted for in the current analysis, this cost may escalate over time as the cumulative dose increases, accompanied by a progressive increase in lung, thyroid and ocular abnormalities. Finally, the low cost estimates in this study for certain procedures may actually underestimate the beneficial effect of amiodarone. Thirty Canadian dollars for a Cardiology consultation ($19 US, 22 Euros) or $63 for a cardioversion ($39 US, 44 Euros) represents a significant undervaluation of physician and hospital services in most areas. For example, the US Medicare fee schedule lists $118 US dollars as the charge for a typical clinical consultation. The resultant cost difference between the two treatment strategies in most practice settings is likely significantly higher than the estimate from this trial. Most clinicians are not surprised by these data, with superior efficacy of amiodarone suggested by other trials and clinical experience showing efficacy in refractory patients. Many will still choose to use propafenone or sotalol as first line agents, notwithstanding these data, especially in patients that are not considered at high risk for proarrhythmia, to minimize longstanding exposure to amiodarone. Despite the aforementioned limitations, the authors are to be commended for a strong study that has convincingly demonstrated the superior antiarrhythmic efficacy and short-term cost efficacy of amiodarone in management of atrial fibrillation compared to sotalol and propafenone. Long term follow-up of this patient population may verify the ongoing cost benefit of amiodarone in reducing the cost of atrial fibrillation management, or it may confirm the downside of prolonged exposure to amiodarone. A. KRAHN G. KLEIN A. C. SKANES R. YEE Division of Cardiology, University of Western Ontario, London, Ontario, Canada