Correlation of heart rate recovery after exercise test with exercise capacity in patients with stable chronic obstructive pulmonary disease / 中华全科医师杂志

ABSTRACT

Objective To explore the correlation between heart rate recovery after exercise test and disease severity in patients with chronic obstructive pulmonary disease(COPD)and assess its impact on the exercise capacity of COPD patients.Methods Arterial blood gas analysis, pulmonary lung function test and cardiopulmonary exercise testing were performed in 60 patients with stable COPD and 50 healthy volunteers.Based on the heart rate recovery after exercise test, COPD patients were divided into normal heart rate recovery group(n =41)and abnormal heart rate recovery group(n =19).Results The COPD patients had lower exercise capacity(peak oxygen uptake as percentage of predicted value, peak VO2％ pred)(66 ± 15vs.89±11, P＜0.01), peak heart rate [(134±21)vs.(149±13)beats/min, P＜0.01], heart rate recovery[(18 ± 9)vs.(27 ± 10)beats/min, P ＜ 0.01] and higher resting heart rate [(83 ± 13)vs.(77 ± 13)beats/min, P ＜0.01] than the controls.Compared with normal heart rate recovery group, forced expiratory volume in one second as percentage of predicted(FEV1 ％ pred)and exercise capacity decreased more significantly in abnormal heart rate recovery group(38 ± 15 vs.52 ± 16, P＜0.05 and 57 ± 12 vs.71 ±14, P ＜0.01).Heart rate recovery was significantly correlated with FEV1％ pred and peak V O2％ pred(r=0.42, P ＜ 0.01 and r =0.52, P ＜ 0.01).Multivariate regression analysis showed that heart rate recovery and FEV1 ％ pred could be used as independent predictors of exercise capacity in COPD patients.Conclusion In COPD patients, heart rate recovery is correlated with the degree of disease severity and it may be an independent predictor of exercise capacity.