Author + information
- Rhidian J. Shelton, MD⁎ ( and )
- John G.F. Cleland, MD, PhD
- ↵⁎Department of Cardiology, Cumberland Infirmary, Newtown Road, Carlisle, Cumbria CA2 7HY, United Kingdom
We read with interest the paper by Suman-Horduna et al. (1) published in the January 2013 issue of the Journal. The investigators analyzed important quality-of-life data from a substantial substudy (n = 749) of a landmark trial (2), comparing rate control to rhythm control for patients with paroxysmal (∼30%) or persistent atrial fibrillation (AF) and congestive heart failure (CHF). Overall, each strategy was associated with similar improvements in symptoms and quality of life, but results were confounded by the high proportion of patients with paroxysmal AF (29.6%) assigned to rate control who remained in sinus rhythm (i.e., crossed over to rhythm control) and by patients assigned to rhythm control who remained in AF (22.4%) (i.e., in whom rhythm control failed).
We previously conducted a small, randomized study exclusively of patients with persistent AF and CHF (3), and encountered similar problems in maintaining sinus rhythm but with no spontaneous return to sinus rhythm in those assigned to rate control; therefore, we had a much lower rate of cross over than in the AF-CHF trial. We found significant improvements in quality of life, left ventricular function, and N-terminal pro–brain natriuretic peptide concentrations overall, which benefited those in whom sinus rhythm was restored and maintained during follow-up. The 6-min walk test distance also improved for patients in whom a rhythm control strategy was successful.
Unfortunately, despite some encouraging results, the Achilles' heel of a rhythm control strategy remains arrhythmia recurrence. Treatment directed at CHF, including angiotensin-converting enzyme inhibitors, beta-blockers, and aldosterone antagonists, helps to reduce the incidence of AF (4). However, safe and effective antiarrhythmic therapy is lacking for patients with left ventricular dysfunction. This includes amiodarone, which was associated with excess mortality in the SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial) study among patients with more advanced symptoms (5). Although preliminary results of catheter ablation, either of AF itself or of atrioventricular nodal ablation followed by biventricular pacing (6), are encouraging, adequately powered randomized clinical trials are needed to evaluate longer term safety and efficacy before any firm recommendations can be made. However, in the context of CHF, the evidence that it is better to be in sinus rhythm rather than AF is compelling. We just need to identify interventions that are less harmful or toxic than the problem.
- American College of Cardiology Foundation
- Suman-Horduna I.,
- Roy D.,
- Frasure-Smith N.,
- et al.
- Shelton R.J.,
- Clark A.L.,
- Goode K.,
- et al.