arteriellvenöse

Arteriellvenöse refers to abnormal connections between arteries and veins that bypass the capillary networks. The term is used for both congenital and acquired vascular lesions and applies across various organ systems. The two main forms are arteriovenous fistulas, which are direct artery-to-vein connections, and arteriovenous malformations (AVMs), which are complex tangles of abnormal vessels with feeding arteries and draining veins.

These shunts alter normal circulation by reducing vascular resistance and increasing venous return. In the brain, AVMs carry a risk of intracranial hemorrhage. Peripheral arteriovenous lesions can present with swelling, a pulsatile mass, audible bruit, limb ischemia, or heart strain if the shunt is large. Large or multiple shunts may lead to high-output heart failure.

Diagnosis typically starts with Doppler ultrasound to assess flow, followed by cross-sectional imaging with CT or MR angiography to delineate anatomy. Digital subtraction angiography remains the gold standard for detailed mapping and treatment planning in many cases.

Management depends on location, size, and symptoms. Small, asymptomatic lesions may be observed. Symptomatic or high-risk lesions are often treated with endovascular embolization to occlude feeding vessels, surgical resection for accessible AVMs, or stereotactic radiotherapy in appropriate brain AVMs. Dialysis-related arteriovenous fistulas require considerations for maintaining or revising access, or creating alternative sites if complications arise. Treatment strategies are individualized, balancing lesion characteristics with potential risks and benefits.