Intrapulmonary arteriovenous anastomoses (IPAVA)

The existence and functional significance of intrapulmonary arteriovenous anastomoses in cardiopulmonary physiology and medicine remains controversial. Our lab has spent >10years investigating the mechanisms regulating blood flow through intrapulmonary arteriovenous anastomoses and have recently provided evidence for significant roles in pulmonary gas exchange efficiency and increased pulmonary pressure in older humans. The significance of this work is that it continues to challenge the idea that all gas exchange inefficiency is primarily restricted to ventilation to perfusion heterogeneity and diffusion limitation. Additionally, our work has led to the discovery that blood flow through intrapulmonary arteriovenous anastomoses contributes to diseases such as stroke (Abushora et al., JASE, 2013) and Beriberi heart (Nakano et al., AJRCCM 2013). Our lab group remains a driving force in this area of research (for review see Lovering, Duke & Elliott Journal of Physiology 2015).

Most significant publications in this area:

S.S. Laurie, J.E. Elliott, R.D. Goodman, A.T. Lovering. Catecholamine-induced intrapulmonary arteriovenous shunting in healthy humans at rest. J Appl Physiol 113: 1213-1222, 2012. PMID: 22858627.

HC Norris, TS Mangum, JW, Duke, TB Straley, RD Goodman, JA Hawn & A.T. Lovering. Exercise- and hypoxia-induced blood flow through intrapulmonary arteriovenous anastomoses is reduced in older adults. J Appl Physiol 116: 1324-1333, 2014. PMID: 24627355

Elliott, J.E., JW Duke, JA Hawn, JR Halliwill & A.T. Lovering. Increased cardiac output, not pulmonary artery systolic pressure, increases intrapulmonary shunt in healthy humans at rest breathing room air and 40% O₂. J Physiol 592 (20) 4537-4553, 2014. PMID: 25085889

Duke, JW, BJ Ryan, JT Davis, KM Beasley, J.E. Elliott, K.M. Beasley, JA Hawn, WC Byrnes, and AT Lovering. Decreased arterial PO₂, not O₂ content, increases blood flow through intrapulmonary arteriovenous anastomoses at rest. J Physiol 594 (17): 4981–4996, 2016. PMID:27062157