SESSION TYPE: COPD: Diagnosis and Evaluation
PRESENTED ON: Sunday, October 21, 2012 at 01:15 PM - 02:45 PM
PURPOSE: Heart rate recovery (HRR) after exercise indicates vagal reactivation and has been shown to predict adverse outcomes in patients with idiopathic pulmonary fibrosis and pulmonary arterial hypertension. Our objectives were to determine values of HRR after six-minute walk test (6MWT) in patients with COPD and to determine its association with pulmonary limitation and exercise performance.
METHODS: HRR1 and HRR2 were defined as the difference in heart rate at the end of a 6MWT and at 1- and 2-minutes of rest respectively. From 2008 to 2011, 80 consecutive patients with COPD underwent 6MWT and were included in the analysis. Logistic regression was used to identify prognostic value of abnormal HRR, chronotropic response, and clinical worsening.
RESULTS: The mean age of this patient group was 65.4 years. Compared with patients in GOLD stage 3 and 4 (n=59), those with GOLD stage 1 and 2 COPD (n=21) had significantly better 6MW distance (1231.05 meters VS 913.07 meters VS, p < 0.0001). There was no statistically significant difference in heart rate at the end of 6MWT (107 VS 106, p = 0.44). Compared to patients with HRR1 ≥ 13 (n=38), those with HRR 1 < 13 (n=42) had worse FEV1% (38.7% VS 48.3%, p = 0.011) and lower 6MW distance (878.9 meter VS 1126.5 meters, p = 0.0006).
CONCLUSIONS: Reduced HRR1 after 6MWT is associated with lower % predicted FEV1 and reduced 6MW distance in patients with COPD. Further study is needed to determine prognostic value of HRR1 in patients with COPD.
CLINICAL IMPLICATIONS: HRR1 has good correlation with % predicted FEV1 and 6MW distance in COPD patients.
DISCLOSURE: The following authors have nothing to disclose: Danai Khemasuwan, Kevin McCarthy, Omar Minai
No Product/Research Disclosure InformationCleveland Clinic Foundation, Cleveland, OH