Male, 31 years old, fever & wheezes

Comment

Comment by Gaspar-Alberto Motta-Ramirez on December 22, 2009 at 10:43am

This is an Arteriovenous fistulas (AVFs) - see also 2 others imagenes and 3 videos - case that are abnormal communications with shunting of blood from an artery to a vein. AVFs mainly involve the peripheral vascular system but can affect virtually any organ or system in the body. They may be congenital, created surgically for hemodialysis, or caused by pathologic processes. This review describes the diverse origins of AVFs and illustrates the spectrum of imaging findings at radiography, ultrasound, CT, MRI, and digital angiography for AVFs in different locations: the CNS, thorax, abdomen, musculoskeletal system, and peripheral vascular system.
The clinical signs of pulmonary AVF depend on the number of fistulas and the sizes of the fistulas. Many patients have no symptoms; others have difficulty breathing and blood in their sputum. When pulmonary involvement is extensive, dyspnea is the most common clinical symptom owing to a right-to-left shunt that produces hypoxemia, a condition that is usually well tolerated. Pulmonary AVF with right-to-left pulmonary shunting is the major cause of transient ischemic attack, brain abscess, and ischemic stroke in patients with Rendu-Osler-Weber syndrome due to paradoxical embolization of bland or septic material into the cerebrovasculature.