Background Atrial fibrillation occurs frequently in patients with congestive heart failure and
commonly results in clinical deterioration and hospitalization. Sinus rhythm may be
maintained with antiarrhythmic drugs, but some of these drugs increase the risk of death.
Methods We studied 1518 patients with symptomatic congestive heart failure and severe left
ventricular dysfunction at 34 Danish hospitals. We randomly assigned 762 patients to
receive dofetilide, a novel class III antiarrhythmic agent, and 756 to receive placebo in a …

Introduction. Atrial fibrillation is a frequent cause of worsening of symptoms in patients with
congestive heart failure. The drugs currently available for maintenance of sinus rhythm all
have major side effects. Methods. In 34 Danish coronary care units, 1518 patients with
congestive heart failure and reduced left ventricular systolic function were randomized to
receive either placebo or a new class III antiarrhythmic drug, dofetilide. The dose of
dofetilide was adjusted according to the presence of atrial fibrillation, the length of the QT …