Immunohistochemical analysis of vascular prostheses implanted with the left ventricular assist system.
BACKGROUND
Dacron vascular prostheses are associated with thromboembolic complications and inflammatory responses; impregnation with bovine collagen reportedly stimulates additional inflammatory/immunologic complications. The Novacor (Baxter Healthcare Corp., Oakland, CA, USA) left ventricular assist system uses Dacron inflow and collagen-impregnated Dacron outflow prostheses.


METHODS
Explanted inflow and outflow prostheses were evaluated for inflammatory/immunologic, hemostatic, anticoagulant, and fibrinolytic pathways. Non-implanted prostheses immersed in whole blood or plasma were used as controls.


RESULTS
Immunoglobulins and complement components were observed in all prostheses with activated macrophages being present only in implanted prostheses. Antithrombin III was observed in all prostheses whereas fibrin, tissue plasminogen activator, and alpha-2 plasmin inhibitor were present only in implanted prostheses. Endothelial and smooth muscle cells associated with vascular structures containing collagen type IV and laminin were observed solely in implanted prostheses.


CONCLUSIONS
An inflammatory response occurs and key components of hemostatic, anticoagulant, and fibrinolytic pathways are present within implanted prostheses. These processes are accompanied by endothelial and smooth muscle cell infiltration which appear to lay the foundation for neovessel development.
Fastenau
D R
DR
Methodist Hospital of Indiana, Indianapolis 46202, USA.
Labarrere
C A
CA
Hormuth
D A
DA
McIntyre
J A
JA
D000990:Antithrombin III / Q000032:analysis; D001807:Blood Vessel Prosthesis; D003165:Complement System Proteins / Q000032:analysis; D004730:Endothelium, Vascular / Q000473:pathology; D005337:Fibrin / Q000032:analysis; D006353:Heart-Assist Devices; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D007150:Immunohistochemistry; D008264:Macrophages / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000473:pathology; D010959:Tissue Plasminogen Activator / Q000032:analysis
D007136:Immunoglobulins; D000990:Antithrombin III; D005337:Fibrin; D003165:Complement System Proteins; D010959:Tissue Plasminogen Activator