Pulmonary Vascular Reserve and Aerobic Exercise Capacity

Abstract

Pulmonary circulation has long been known to have specific proprieties of recruitment and distention to keep the hemodynamic pressure low even when facing very high blood flow. Aerobic exercise especially at high intensity has the particularity to increase considerably the cardiac output. The ability of the pulmonary circulation to face high blood flow with maintaining low pressures is considered as the pulmonary vascular reserve. Furthermore, high pulmonary vascular reserve has been shown to be characterized by low pulmonary vascular resistance, high pulmonary vascular distensibility, high pulmonary capillary volume, and high lung diffusing capacity allowing for lower ventilation at a same metabolic cost. The pulmonary vascular reserve thus reflects the capacity of the pulmonary circulation, including the capillary network, to adapt to high exercise levels. Interestingly, a high pulmonary vascular reserve is an advantage as it is associated with a superior aerobic exercise capacity (VO 2 max). This observation strongly suggests that exercise capacity is modulated by the functional state of the pulmonary circulation. However, why or when pulmonary vascular reserve may be related to a higher aerobic exercise capacity remains incompletely understood. The present chapter will discuss the role of each component of the pulmonary vascular reserve during exercise and develop the factors able to influence the pulmonary vascular reserve in heathy individuals.

The association of six‐minute walk work and other clinical measures to cardiopulmonary exercise test parameters in pulmonary vascular disease

“…Other investigations in other cohorts have shown associations between TLCO and VE/VCO 2 in other cohorts [27][28]. This could be due to higher TLCO allowing for better maintenance of gas exchange at lower ventilation costs [29].…”

“…27,28 This could be due to higher TLCO allowing for better maintenance of gas exchange at lower ventilation costs. 29 This study has a number of limitations. Our PVD cohort consisted of CTEPH and CTED patients and therefore our findings may not be applicable to a PAH cohort due to the different pathophysiology and disease characteristics.…”

Isolated Exercise-Induced Pulmonary Hypertension Associates with Higher Cardiovascular Risk in Scleroderma Patients

“…According to clinical experience, some patients with scleroderma who are still oligosymptomatic do much better than others in terms of exercise capacity, WHO-FC, and therefore in quality of life. They may differ in their pulmonary vascular reserve, defined as the ability of the pulmonary circulation to adapt to a higher blood flow while maintaining low pressure during high exercise levels [ 16 , 17 ]. A high pulmonary vascular reserve is characterized by low pulmonary vascular resistance, a high pulmonary vascular distensibility, a high pulmonary capillary volume, and a high pulmonary diffusion capacity [ 16 ].…”

“…They may differ in their pulmonary vascular reserve, defined as the ability of the pulmonary circulation to adapt to a higher blood flow while maintaining low pressure during high exercise levels [ 16 , 17 ]. A high pulmonary vascular reserve is characterized by low pulmonary vascular resistance, a high pulmonary vascular distensibility, a high pulmonary capillary volume, and a high pulmonary diffusion capacity [ 16 ]. Thus, pulmonary vascular reserve is modulated by the functional state of the pulmonary circulation, and the greater the pulmonary vascular reserve, the lower the likelihood of progressing through risk classes.…”