TY - CHAP M1 - Book, Section TI - Pulmonary Arteriovenous Malformations A1 - Peck, Tyler J. A1 - Rodriguez-Lopez, Josanna M. A2 - Grippi, Michael A. A2 - Antin-Ozerkis, Danielle E. A2 - Dela Cruz, Charles S. A2 - Kotloff, Robert M. A2 - Kotton, Camille Nelson A2 - Pack, Allan I. Y1 - 2023 N1 - T2 - Fishman’s Pulmonary Diseases and Disorders, 6e AB - In the normal pulmonary circulation, blood leaves the right ventricle of the heart via the pulmonary artery, and the entire blood volume is routed to the pulmonary capillary bed adjacent to alveoli, allowing for gas exchange. The normal diameter of blood vessels making up the pulmonary capillary bed is approximately 6 µm.1 After drainage from the pulmonary capillaries, the blood then returns to the heart via the pulmonary veins. Pulmonary arteriovenous malformations (PAVMs) are abnormal vascular connections between pulmonary arteries and pulmonary veins, preventing exposure of blood to normal pulmonary capillaries and many times leading to hypoxemia due to shunting of deoxygenated blood into the pulmonary venous system and into the systemic circulation. Additionally, the size of these abnormal connections is typically larger than the size of pulmonary capillaries, allowing for transmission of particles in the blood stream (e.g., venous thromboemboli) from the venous circulation into the arterial circulation, leading to complications like stroke or septic emboli. Pulmonary AVMs are commonly aneurysmal and can frequently be seen macroscopically on advanced imaging (e.g., CT angiography). SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accessmedicine.mhmedical.com/content.aspx?aid=1195008477 ER -