Vascular procedures that thermo-coagulate collagen reduce local platelet deposition and thrombus formation: laser and laser-thermal versus balloon angioplasty.
OBJECTIVE
Exposure of the arterial wall matrix to blood leads to platelet deposition resulting in thrombosis. Because heat alters tissue matrix we proposed that heating reduces platelet deposition.


METHODS
Sixty arterial homografts (15 dogs) were mounted in an arterio-venous "shunt." Interventions included balloon angioplasty (BA), direct laser (LA), laser-thermal (LTA), and combined LTABA. 111Indium-labeled platelets were circulated, radio activity measured, and homografts processed for histology.


RESULTS
Radioactivity count (mean+/- SE) at BA sites (13,853+/-3,192 cpm/cm(2)) was greater than LA (7,038+/-981), LTA (5,294 +/-1,145), LTABA (6,176+/-1,571), and control (1,826+/-339), P<0.05. Electron microscopy showed fewer platelets at LA, LTA, and control than BA sites. BA spread the collagen on the arterial lumen while heat gelled collagen and confined it to the arterial media.


CONCLUSIONS
Heating the artery and gelling collagen during LA, LTA, or LTABA significantly reduced thrombogenicity.
Abela
G S
GS
Department of Medicine, Division of Cardiology, Michigan State University, East Lansing, Michigan 48824, USA. abela@pilot.msu.edu
Hage-Korban
E E
EE
Tomaru
T
T
Barbeau
G R
GR
Abela
O G
OG
Friedl
S E
SE
D000800:Angioplasty, Balloon; D016342:Angioplasty, Laser; D000818:Animals; D003094:Collagen / Q000378:metabolism*; D003131:Combined Modality Therapy; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D006979:Hyperthermia, Induced; D008297:Male; D010973:Platelet Adhesiveness; D010974:Platelet Aggregation; D011489:Protein Denaturation; D013927:Thrombosis / Q000517:prevention & control*
D003094:Collagen