ABSTRACT
The hemodynamic properties of arteriovenous malformations (AVMs) have been the subject of observation and speculation for many years. The first hemodynamic observations about arteriovenous fistuale were made by William Hunter, who reported in 1764 on a ‘‘particular species of aneurysm... where there is an anastomosis... between the artery and vein... so that blood passes immediately from the trunk of the artery into the trunk of the vein’’ arising as a complication of phlebotomy at the elbow (1). He observed ‘‘the artery... will become larger in the arm, and smaller at the wrist, than it was in the natural state’’ and the vein ‘‘will be dilated or become varicose.’’ He defined the anatomical changes as due to hemodynamic factors, as he explained ‘‘the stream from the (proximal) artery (becomes) larger.’’ This observation clearly demonstrates many of the key features present in AVMs of the brain.
