Case report: the clinical significance of an azygous anterior cerebral artery

This case reports the presentation of a 67-year-old Caucasian male who presented to the Emergency Department unresponsive after suffering what appeared to be an intracerebral bleed. A bleed was not confirmed at CT and the patient started to regain consciousness and the clinical picture improved over the next few days. A follow-up inpatient MRI revealed a single anterior cerebral artery, known as an azygous anterior cerebral artery. The presence of this rare anatomical variant and its potential associated anomalies proved a major consideration in the administration of routine deep vein thrombosis (DVT) prophylaxis. Administration of routine DVT prophylaxis had the potential to further exacerbate injury. Unfortunately the patient suffered a fatal pulmonary embolus before a definitive treatment plan could be arranged. This case highlights the need for early involvement of specialist advice, access to advanced imaging modalities and hopes to raise the awareness of this rare anatomical variant and give consideration to its potential serious complications with fellow clinicians.