The presence of chronotropic incompetence (CI) and abnormal heart rate recovery (HRR) gives out a suggestion on autonomic dysfunction (AD). It is associated with the increased cardio-vascular (CV) risk and diminished physical activity.

Researchers aimed to analyze the correlation between airflow obstruction and AD- forced expiratory volume in 1s (FEV1), disease prognosis, and dynamic hyperinflation (DH)- the BODE … index (BMI; Obstruction … FEV1;Dyspnea … mMRC;E … exercise capacity) in the non-severe COPD patients without the overt CV comorbidities.

Cardio-pulmonary exercise testing (CPET) was used with 67 subjects. In addition, the performance of DH assessment for inspiratory capacity (IC) maneuvers were performed. The execution of echocardiography was done before CPET and few minutes a after the peak exercise.

It was assumed that the stress left ventricular diastolic dysfunction (LVDD) for the calculation of metabolic-chronotropic relationship (MCR) with formula E/e… > 15.Wilkoff method was used. Abnormal HR recovery (HRR) and Chronotropic incompetence (CI) were determined. 

The detection of CI in 65% of moderate and 44% of mild COPD patients. Abnormal HRR was present in 78% of moderate and 75% of mild COPD subjects. The analysis for multivariate regression showed no association between AD, stress LVDD, BODE index, CEPT parameters, and FEV1

The analysis of AD during incremental CPET unraveled lung hyperinflation as one of the potential mechanisms for diminished physical activity and attenuated HR response in non-severe COPD free of overt CV comorbidities. 

The multifaceted approach to dyspnea may facilitate the discrimination between the improvement and pathogenesis of proper clinical management.

Reference: sciencedirect.com/science/article/pii/S2531043720302646