Effects of heart failure on cerebral blood flow in COPD: Rest and exercise

ABSTRACT

Cerebral blood flow (CBF) and oxygenation (COx) are generally well-preservedin COPD. It is unknown whether prevalent cardiovascular co-morbidities, suchas heart failure, may impair CBF and COx responses to exertion. Eighteen maleswith moderate-to-severe COPD (8 with and 10 without overlapping heart failure)underwent a progressive exercise test with pre-frontal CBF and COxmeasurements (indocyanine green and near-infrared spectroscopy). Meanarterial pressure and cardiac output were lower from rest to exercise in overlap. Only COPD patients demonstrated an increase in arterialized PCO2 towards theend of progressive exercise. CBF index was consistently higher and increasedfurther by ~40% during exercise in COPD whereas a ~10% reduction wasobserved in overlap. COx was lower in overlap despite preserved arterialoxygenation. In conclusion, heart failure introduces pronounced negative effectson CBF and COx in COPD which may be associated with clinically relevantoutcomes, including dyspnea, exercise intolerance, cerebrovascular disease and cognition...