Arteriovenous malformations

Arteriovenous malformations (AVM) are vascular malformations that consist of a convolute of vessels. Whether these malformations are congenital or develop in the course of life has not yet been conclusively clarified. As with fistulas, AVMs also result in a short circuit between the arterial (high-pressure) system and the venous (low-pressure) system. As a result, the pressure on the low-pressure system is significantly too high. Over the course of years, this can lead to increasing dilation of the venous vessels and bleeding. In addition, more blood flows through the AVM than through the surrounding brain tissue, as the resistance in the short-circuit connection is lower. The increase in blood flow can lead to the formation of aneurysms (so-called flow-associated aneurysms).

Whereas in the past it was more advisable to treat an AVM even if it had not bled before, nowadays people are more cautious. Today, only flow-associated aneurysms are often treated with coils. In general, the treatment options consist of surgery, embolization (artificial closure) with special adhesives, radiotherapy or a combination of these procedures. Once the AVM has led to bleeding, treatment must be carried out. Every patient with an AVM is discussed on an interdisciplinary basis by the Neurovascular Board at the University Hospital of Cologne in order to provide the best possible individual treatment recommendation.