Carotid artery pseudoaneurysm in a cat

Clinical summary: A 4-month-old female intact domestic shorthair cat presented to Kansas State University Veterinary Medical Teaching Hospital for investigation of a large, firmly adhered mass in the left mid-cervical region that developed after phlebotomy performed at the referring veterinarian’s clinic. Ultrasound examination of the mass revealed a cystic structure in communication with the left carotid artery, with bidirectional blood flow through the area. A diagnosis of pseudoaneurysm secondary to accidental needle penetration of the carotid artery during jugular venepuncture was made. Outcome: Strict cage rest and pain management resulted in complete resolution of clinical and ultrasonographic signs in this cat.