New trials in atrial fibrillation

Large-scale clinical trials in atrial fibrillation (AF) now are addressing issues other than that of thromboembolic prophylaxis. The "rate versus rhythm" debated is fundamental--whether to accept the occurrence of AF and attempt control of the ventricular rate or to strive for the restoration and maintenance of sinus rhythm. The AFFIRM, PIAF, and RACE trials will provide information about the efficacy, costs, adverse effects, and benefits of attempting to maintain sinus rhythm. Atrial pacing is associated with less AF than ventricular pacing, and trials (AFT, SYNBIAPACE, and DAPPAF) now are assessing the antiarrhythmic efficacy of atrial pacing, including dual-site pacing and special algorithms compared with no pacing.