Background: Decreased heart rate recovery (HRR) is a predictor of mortality in patients with coronary artery disease and preserved left ventricular function. We investigated the changes in HRR and assessed the impact of beta-blockade therapy on these parameters in patients with symptomatic congestive heart failure (CHF).
Methods and results: HRR, defined as the difference from peak exercise heart rate (HR) to HR measured at 1, 2, and 3 minutes after maximal exercise test, was studied in 23 stable CHF patients and 12 healthy subjects. Patients with CHF performed a maximal exercise test using a Ramp protocol before and after 6 months of therapy with either metoprolol or carvedilol. Patients with CHF exhibited a significantly attenuated HRR compared with healthy subjects at 1 minute (17.8 +/- 5.8 versus 26.8 +/- 16.2 beats), 2 minutes (34.0 +/- 10.6 versus 48.0 +/- 11.2 bpm) and 3 minutes (41.0 +/- 12.4 versus 60.0 +/-12.4 bpm) after exercise (P<.05 for all parameters). Beta-blocker therapy for 6 months did not significantly improve HRR.
Conclusion: HRR is markedly attenuated in stable CHF patients compared with healthy subjects. Long-term beta-blocker therapy appears to cause no significant improvement in HRR up to 3 minutes after maximal exercise.