Therapeutic target with beta blockers in heart failure, i.e., target heart rate reduction or beta-blocker dose, is controversial. To resolve this controversy, the authors studied 152 heart failure patients on beta blockers who were divided into four groups based on median peak exercise heart rate reduction as compared with predicted and prescription of at least 50% recommended beta-blocker dose. Event-free survival (vs. death or assist device placement or urgent transplantation) was compared. Baseline and peak exercise heart rates were 74 +/- 14 and 116 +/- 21 bpm, respectively. Median heart rate reduction at peak exercise was 35%. When median or higher peak heart rate reduction was achieved, there were no significant survival differences noted between patients on different beta-blocker doses. With below-median peak heart rate reduction, there was a strong trend toward better event-free survival with higher beta-blocker doses. In conclusion, the results suggest that higher heart rate reduction is associated with better outcomes for heart failure patients overall and, for patients with persistently elevated heart rates, higher beta-blocker doses provided additional benefit.