Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + • Congenital or acquired• Abnormal connection between artery and vein; located anywhere in body +++ Congenital + • Systemic effect minimal• Noted in infancy or childhood• Limb involvement leads to hypertrophied, longer extremity• Frequently involve brain, viscera, lungs• Osler-Weber-Rendu syndrome (autosomal dominant): Hemorrhages in form of epistaxis, GI bleeding, polycythemia, cyanosis, clubbing +++ Acquired + • Enlarge rapidly• Can cause heart failure• Generally, result from trauma or disease• Venous malformations: Rarely cause hemodynamic effects +++ Epidemiology +++ Acquired + • Most commonly a result of traumatic injury• Iatrogenic injury after angiography or angioplasty common• Connective tissue disorders (Ehlers-Danlos), erosion of mycotic aneurysm, communication with prosthetic graft, neoplastic invasion can cause false aneurysm and arteriovenous fistula• Rare cause is injury to aorta and inferior vena cava after excision of herniated disk +++ Symptoms and Signs + • Determine time of onset and presence of associated disease• Continuous murmur may be heard• Palpable thrill and increased skin temperature• Proximal vein dilatation, distal pulse diminished, distal coolness• Tachycardia: Increased cardiac output• Branham sign: Compression of fistula results in slowed heart rate• Venous malformations: Mass; may be tender; no hemodynamic effects +++ Imaging Findings + • MRI study of choice for peripheral AV malformations• Angiograms give precise delineation of AV fistulas + • Evaluate for signs of systemic or distant intravascular infection + • Physical exam• Duplex US or MRI for most peripheral lesions• Occasionally, use angiography to delineate further + • Not all require treatment +++ Venous Fistulas + • Compression garments when possible• Injection of sclerosing agents possible +++ AV Fistulas + • Monitor small peripheral fistulas• Most managed with radiographic embolization; head and neck, pelvis best• Surgical: Ligate all feeding vessels; amputate extremity; repair of fistula, oversewing defects (avoid for congenital fistulas) +++ Congenital + • En bloc resection of all tissue involved in fistula +++ Surgery +++ Indications + • Hemorrhage• Expanding false aneurysm• Severe venous or arterial insufficiency• Cosmesis• Heart failure +++ Contraindications + • Congenital fistula (relative) +++ Prognosis + • Vary according to extent, location, and type• Traumatic type has better prognosis• Congenital has worse prognosis because of high recurrence +++ References ++Jacobowitz GR et al. Transcatheter embolization of complex pelvic vascular malformations: results and long-term follow-up. J Vasc Surg. 2001;33:51. [PubMed: 11137923] ++White RI Jr et al. Long-term outcome of embolotherapy and surgery for high-flow extremity arteriovenous maformations. ... Your Access profile is currently affiliated with [InstitutionA] and is in the process of switching affiliations to [InstitutionB]. Please select how you would like to proceed. Keep the current affiliation with [InstitutionA] and continue with the Access profile sign in process Switch affiliation to [InstitutionB] and continue with the Access profile sign in process Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Error: Incorrect UserName or Password Username Error: Please enter User Name Password Error: Please enter Password Sign in Forgot Password? Forgot Username? Download the Access App: iOS | Android Sign in via OpenAthens Sign in via Shibboleth You already have access! Please proceed to your institution's subscription. Create a free profile for additional features.