Spontaneous regression of brain arteriovenous malformations

Abstract

Spontaneous regression of a brain AVM is the result of multiple interacting factors. Intracranial hemorrhage and the presence of a single draining vein seem to play a major role in this process.

Progressive regression of intracranial arteriovenous malformations after Onyx embolization

“…As far as factors associated with progressive AVMs regression after embolization are concerned, the literature data are sparse and based merely on case-reports [9,13]. A greater number of reports have been devoted to the still exceptional and insufficiently understood phenomenon of spontaneous AVM thrombosis [11,12,[14][15][16][17]. In this group the most important predictors for AVM regression are hemodynamic changes caused by intraparenchymal bleeding and small size of AVM with a single draining vein [11,12,[14][15][16][17].…”

“…A greater number of reports have been devoted to the still exceptional and insufficiently understood phenomenon of spontaneous AVM thrombosis [11,12,[14][15][16][17]. In this group the most important predictors for AVM regression are hemodynamic changes caused by intraparenchymal bleeding and small size of AVM with a single draining vein [11,12,[14][15][16][17]. In case of intracerebral hematoma and associated brain edema the mass effect on the feeding arteries may diminish blood flow in the AVM what results in thrombosis in draining vessels [12,15,16,18].…”

Rendering a ruptured arteriovenous malformation more susceptible to spontaneous obliteration as a possible treatment strategy for cerebral AVM

“…It has been postulated that this phenomenon is closely correlated with various clinical or radiological features. For example, AVM with hemorrhagic presentation has been shown to be related to this phenomenon [2, 3]. Possible causes include ‘mass effects’ or ‘brain swelling’ secondary to parenchymal hemorrhage.…”

“…AVMs harboring only a single draining vein have also been shown to have a greater chance of undergoing spontaneous regression than those with multiple draining veins [2]. A possible explanation for this is that venous outflow obstruction can lead to flow stasis inside the AVM nidus, and obstruction of a single vein is more likely to occur than obstruction of multiple draining veins [4].…”

“…While most AVMs require treatment when they become symptomatic or even rupture [1], other AVMs might regress spontaneously without any treatment or following partial treatment [2]. …”