Randomized, double-blind, simple, multicenter, international trial with 186 centers in the United States and 116 in Canada. In the main trial, patients with left ventricular ejection fractions of 0.45 or less were randomly assigned to digoxin (3397 patients) or placebo (3403 patients) in addition to diuretics and ACE inhibitors. In an ancillary trial of patients with ejection fractions greater than 0.45, 492 patients were randomly assigned to digoxin and 496 to placebo. Patients were recruited over a three-year period at the 302 centers and followed for a minimum of two years. Patient enrollment began in February 1991 and ended in September 1993. Follow-up ended in December 1995. The main results paper was published in 1997.