A retrospective analysis was performed on 52 patients with heart failure to determine the change in beta-blocker therapy after cardiac resynchronization therapy (CRT). After 6 months of CRT, the number of patients receiving beta-blocker therapy increased from 36 to 44, with improved clinical outcomes and larger beta-blocker doses, indicating that these 2 therapies may work together to improve outcomes by allowing the use of larger doses of beta blockers while correcting ventricular dyssynchrony.