Fetal brain perfusion is supplied by the primitive dorsal aorta anteriorly, longitudinal neural arteries posteriorly, and anastomotic transverse segmentals. Most notable of these connections are the primitive trigeminal, otic, hypoglossal, and proatlantal arteries. With cranial-cervical circulatory maturation and development of the posterior communicating segments and vertebro-basilar system, these primitive segmental anastomoses normally regress. Anomalous neurovascular development can result in persistence of these anastomoses. Due to its territory of perfusion, the persistent primitive hypoglossal artery (PPHA) is associated with vertebral artery and posterior communicating artery hypoplasia or aplasia. As a consequence, primary blood supply to the hindbrain comes chiefly from this single artery. Although usually clinically silent, PPHA is susceptible to common cerebrovascular disorders including athero-ischemic disease and saccular aneurysmal dilation to name a few. We present a case of transient ischemic attack in a patient with a PPHA and proximal atherosclerotic disease treated by endovascular stenting.