Deposition of platelets and neutrophils in porcine iliac arteries after angioplasty and Wallstent placement compared with angioplasty alone.
OBJECTIVE
This study was designed to compare deposition of 111In-labeled platelets and neutrophils after balloon angioplasty (PTA) alone and PTA plus Wallstents.


METHODS
Histological investigation was performed with scanning electron microscopy (SEM). Fifty percent stenoses of both iliac arteries was created by resorbable ligature in 13 pigs. After 30 days, PTA was performed bilaterally with an additional stenting procedure done on one side. Autologous platelets were labeled and reinfused before the interventional procedure in six pigs, and labeled neutrophils were used in seven pigs. The deposition of the labeled cells was recorded in vivo over 270 min using a scintillation camera. The results were correlated with in vitro measurements.


RESULTS
Scanning revealed significant increase in platelet and neutrophil deposition at the site of the stent compared with the site where PTA alone was undertaken. In vitro measurements confirmed these differences. SEM demonstrated a fibrin lining on the stent surface and numerous adherent platelets. The adjacent arterial lumen was almost completely covered by fibrinous material. The PTA-alone site demonstrated denudation of endothelial cells and less fibrinous material, as well as platelets and leukocytes.


CONCLUSIONS
The complex interaction in the response of the vessel wall and flowing blood involves both platelet and neutrophil adhesion. The self-expandable vascular endoprosthesis contributes to increased deposition of platelets and neutrophils as seen in this experimental model of nonatheromatous stenosis.
Pärsson
H
H
Department of Surgery, Lund University, Sweden.
Cwikiel
W
W
Johansson
K
K
Swartbol
P
P
Norgren
L
L
D000800:Angioplasty, Balloon; D000818:Animals; D001792:Blood Platelets / Q000473:pathology*; D002448:Cell Adhesion; D005260:Female; D007083:Iliac Artery / Q000473:pathology*; D007205:Indium Radioisotopes; D008297:Male; D008855:Microscopy, Electron, Scanning; D009504:Neutrophils / Q000473:pathology*; D010973:Platelet Adhesiveness; D015607:Stents; D013552:Swine
D007205:Indium Radioisotopes