LONG-TERM RESTENOSIS AFTER MULTIPLE STENT IMPLANTATION - A QUANTITATIVE ANGIOGRAPHIC STUDY

Elective high pressure stent implantation in focal coronary lesions ha s a high procedural success and low incidence of restenosis in compari son with balloon angioplasty. For the treatment of diffusely diseased coronary arteries, however, a high incidence of subacute thrombosis an d late restenosis has been reported. The aim of this study was the pro spective evaluation of procedural and long-term outcome after implanta tion of multiple stents. In a consecutive series of 48 patients, 48 le sions were treated with the implantation of 120 stents (2.5 +/- 1.0 st ents/lesion). Stent implantation was performed electively in 15%, for dissection in 56%, and for suboptimal balloon angioplasty result in 29 % of patients. The lesion length before stenting including balloon ang ioplasty induced dissections, was 28.5 +/- 9.8 mm (range 20-62), the m ean length of the stented segment was 40 +/- 16 mm. The procedure was successful in 45 patients (95%). Procedural related complications incl uded two urgent bypass operations (4%) and one transmural myocardial i nfarction (2%). Two subacute stent thrombosis events (4%) occurred, bo th in-hospital, 1 and 3 days after implantation, Follow-up was obtaine d in 43 eligible patients at 6.4 +/- 1.3 months, revealing an overall restenosis rate of 30% (13 patients). Quantitative angiography (CAAS I I, edge detection algorithm) showed a minimal lumen diameter of 0.93 /- 0.28 mm (diameter stenosis 62% +/- 13%) before treatment, 2.81 +/- 0.26 mm (diameter stenosis -4 +/- 13%) after stenting, and 1.79 +/- 0. 58 mm (diameter stenosis 30% +/- 20%) at follow-up. Predictors of rest enosis were not identified, Thus, multiple stent implantation has high procedural success and the late restenosis of long lesions after mult iple stents compares favorably with balloon angioplasty.