Peripheral hepatic arterial embolization with crosslinked collagen fibers.

Hepatic artery embolization with a nonimmunogenic, crosslinked microfibrillar collagen preparation (Angiostat, Collagen for Embolization, Target Therapeutics, Los Angeles, CA) was studied in mongrel dogs. Flow-directed technique was used to achieve complete distal arterial occlusion. Serial liver function evaluation demonstrated marked alterations at 48 to 72 hours, partial correction at one week, and resolution of abnormalities by one month. Restoration of large vessel blood flow was angiographically demonstrable at one week. Follow-up arteriograms showed no persistent arterial occlusion. Collagen was demonstrated in vessels of 20 to 250 micron. Recanalization was achieved by migration of endothelial cells around the collagen, development of a new vascular channel within an endothelial cell cleft, and subsequent complete removal of the collagen over a three- to four-month period. Three months after embolization with a single dose, normal hepatic vascular and tissue anatomy and hepatic function were restored completely. Repeated embolization at two weekly intervals was well tolerated.