We have described a variant of the structure of the vertebral artery. In the V3 segment, the vertebral artery bifurcated and then joined again. This building looks like a triangle. Such anatomy has not been previously described in the world literature. By the right of the first description, this anatomical formation was called the «vertebral triangle of Dr A.N. Kazantsev». This discovery was made during stenting of the V4 segment of the left vertebral artery in the most acute period of stroke.