Decreased heart rate recovery after exercise in patients with congestive heart failure: effect of beta-blocker therapy.

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.