Complications in the natural course — Arteriovenous malformation

The natural course of an arteriovenous malformation (AVM) can be stable over many years, but typically it progresses in phases. However, an exact prognosis of the individual natural course of the disease is difficult to make because of the diverse manifestations of the clinical picture.

Initially, the arteriovenous malformation can have direct effects on the surrounding tissues, which include compression or invasion and edema.

As a result of the aforementioned hemodynamics of an arteriovenous malformation with direct shunts from the arterial to the venous system, venous hypertension with subsequent chronic venous insufficiency can occur, especially in the lower extremity. Concurrent arterial ischemia in the vicinity of the lesion can increase the complications caused by venous insufficiency, such as ulcers and pain.

In superficially located arteriovenous malformations, spontaneous bleeding may occur, especially in the presence of a wound. In the case of very large arteriovenous malformations, the slow but steady progression resulting from the increased blood flow/shunt volume may lead to increased cardiac output with subsequent tachycardia and ventricular dilatation or hypertrophy and ultimately high-output cardiac failure. Tachyarrhythmias also occur in this context.