Exercise-induced intrapulmonary arteriovenous shunt in healthy women

The purpose of this study was to determine if healthy young women of various aerobic fitness levels are vulnerable to intrapulmonary arteriovenous shunts (IPAVS) at sub maximal work rates. Female volunteers (n = 24) performed semi-recumbent cycling exercise to exhaustion and agitated saline contrast echocardiography was used to determine the presence of IPAVS at rest, during exercise, and post exercise. Subjects were classified as untrained (UT, n = 8), moderately trained (MT, n = 6) and highly trained (HT, n = 10) based on their respective V˙O2,peak (UT = 35 ± 5; MT = 43 ± 1 and HT = 50 ± 3 ml kg−1 min−1). We found that the % V˙O2,peak at IPAVS onset was not significantly different between women of varying fitness (P > 0.05). The majority of individuals exhibited IPAVS during modest levels of exercise intensity. In conclusion, there is no association between aerobic capacity or exercise intensity at IPAVS onset in women performing semi-recumbent cycle exercise.

► We studied intrapulmonary arteriovenous shunt in women of varying fitness levels.
► The majority of individuals exhibited shunt during modest exercise intensity.
► Shunt onset occurred in women with varying degrees of aerobic capacity.