Flow disturbances in carotid and vertebral arteries in symptomatic patients referred for pacemaker implantation.

Background: Electrocardiographic abnormalities and clinical symptoms are used as indications for cardiac pacing. Syncope, faints and other neurological symptoms are of multi-factorial origin and are due to reduced brain perfusion.

Aim: To examine the carotid and vertebral artery blood flow and to assess whether stenosis of these arteries is associated with symptoms of cerebral hypoperfusion in patients undergoing pacemaker implantation.