What phenomenon is dramatically illustrated in this angiogram which accounts for the patients cardiac failure?
There is marked shunting of contrast through the malformation, such that there appears to be no capillary phase. Rather the contrast passes directly from the carotids through the malformation and into the jugular system. This results in a tremendous volume load on the heart which eventually fails, unable to keep up with the demands of the shunt.
What are some of the general principles which guide endovascular management?
Both venous and arterial embolisation is possible, depending on the the number of feeders, and controversy persists in regards to the optimum approach. Ideally embolisation is deferred until 6 months of age for choroidal VGM and later for mural types, to allow the cavernous sinus to mature. If cardiac failure is refractory to medical management, embolisation may be performed sooner.
Selective injections of the left vertebral artery demonstrate strikingly fast shunting of contrast through the malformation with little parenchymal contrast blush. Angiogram courtesy of Prof. Peter Mitchell.