Pulmonary rehabilitation improves cardiovascular response to exercise in COPD.

BACKGROUND

Pulmonary rehabilitation (PR) has emerged as a recommended standard of care in symptomatic COPD.

OBJECTIVES

We now studied whether PR may affect cardiovascular response to exercise in these patients.

METHODS

Twenty-seven patients (9 females aged 69 ± 8 years) with moderate-to-severe airflow obstruction admitted to a 9-week PR course performed a pre-to-post evaluation of lung function test and symptom-limited cardiopulmonary exercise test (CPET). Oxygen uptake (VO2), tidal volume (V(T)), dyspnea and leg fatigue scores were measured during CPET. Cardiovas-cular response was assessed by means of oxygen pulse (O2Pulse), the oxygen uptake efficiency slope and heart rate recovery at the 1st min.

RESULTS

A significant increase in peak VO2 and in all cardiovascular parameters (p < 0.05) was found following PR when compared to baseline. Leg fatigue (p < 0.05), but not dyspnea, was significantly reduced after PR. When assessed at metabolic and ventilatory iso levels [% VCO2max and % minute ventilation (VEmax)], O2Pulse and V(T) were significantly higher (p < 0.05) at submaximal exercise (75 and 50% of VCO2max and VEmax) after PR when compared to baseline. V(T) percent changes at 75% VCO2max and 75% VEmax after PR significantly correlated with corresponding changes in O2Pulse (p < 0.01).

CONCLUSIONS

In COPD patients, a PR training program improved the cardiovascular response during exercise at submaximal exercise independent of the external workload. This change was associated with an enhanced ventilatory function during exercise.