Relationship between diastolic function and heart rate recovery after symptom-limited exercise.

BACKGROUND

Autonomic abnormalities have been implicated in both diastolic dysfunction and abnormal heart rate (HR) recovery; however, few studies have assessed whether diastolic dysfunction is associated with abnormal HR recovery and whether both modify exercise capacity.

METHODS AND RESULTS

Exercise echocardiography with diastolic assessment was performed in 2,826 patients with normal wall motion responses to symptom-limited exercise testing. HR recovery was defined as the difference in HR from peak exercise to 1 minute in recovery; abnormal HR recovery was defined as the lowest quartile. Mean HR recovery was 32 ± 14 beats per minute. Patients with diastolic dysfunction or abnormal HR recovery had lower exercise capacity, and those with both had the lowest exercise capacity (P < .0001 compared with normal responses). Indices of abnormal diastolic function were correlated with abnormal HR recovery. In multivariable analysis, after age diastolic dysfunction (referent: normal diastolic function) was the strongest predictor of abnormal HR recovery (adjusted odds ratio [OR] 1.47, 95% confidence interval [CI] 1.20-1.80) and incrementally predictive of chronotropic incompetence (adjusted OR 1.42, 95% CI 1.16-1.74).

CONCLUSIONS

Diastolic dysfunction is independently associated with abnormal HR recovery after symptom-limited exercise. Further studies are needed to determine if diastolic function modifies the adverse outcomes observed in those with abnormal HR recovery.