PROLIFERATIVE RESPONSE IN SMOOTH-MUSCLE CELLS AFTER ANGIOPLASTY OR INSERTION OF SELF-EXPANDING STENTS - AN EXPERIMENTAL-STUDY IN PIGS

Purpose: Evaluation of the early proliferative reaction of smooth musc le cells (SMC) in the media of the artery following percutaneous trans luminal angioplasty (PTA), compared with the reaction on insertion of self-expandable stents. Material and Methods: In 6 healthy pigs, one i liac artery was overdilated with an 8-mm diameter angioplasty balloon. A self-expanding Nitinol stent, OD 8 nun, was inserted into the contr alateral iliac artery without previous dilatation. The nuclei of the p roliferating SMC in the media of the artery were labelled by intraveno us administration of 5-bromo-2-deoxy-uridine and cells in S-phase coun ted 24 h after the procedure. Results: The mean number of proliferatin g nuclei of the SMC increased significantly more after PTA (p<0.05) th an after the insertion of a stent. Conclusion: Early proliferative rea ction of the SMC is more pronounced after PTA than after insertion of the self-expanding stent.