Stented segment length as an independent predictor of restenosis

OBJECTIVES: We sought to evaluate the relation between stented segment length and restenosis. BACKGROUND: Multiple or long coronary stents are now being implanted in long lesions or in tandem lesions. A longer stented segment might result in a higher probability of restenosis. However, there is little information available on the relation between stented segment length and restenosis. METHODS: Between April 1995 and December 1996, 725 patients with 1,090 lesions underwent stenting. Lesions were divided into three groups according to the length of the stented segment: 1) group I (n = 565): stented segment length ≤20 mm; 2) group II (n = 278): stented segment length >20 but ≥35 mm; and 3) group III (n = 247): stented segment length >35 mm. RESULTS: There was no significant difference in the incidence of subacute stent thrombosis among the three groups (0.4% in group I, 0.4% in group II, 1.2% in group III; p = NS). The minimal lumen diameter (MLD) after stenting was greater in group I than in group III (3.04 ± 0.60 mm in group I, 3.01 ± 0.54 mm in group II, 2.91 ± 0.58 mm in group III; p <0.05). At follow up, a smaller MLD was observed in group III as compared with group I and group II (2.04 ± 0.93 mm in group I, 1.92 ± 1.00 mm in group II, 1.47 ± 0.97 mm in group III; p <0.01). The restenosis rates were 23.9% in group I, 34.6% in group II and 47.2% in group III (p <0.01). Using multivariate analysis, the longer stented segment, the angiographic reference vessel diameter and the percent diameter stenosis after stenting were independent predictors of restenosis. CONCLUSIONS: The present study shows that a longer stented segment is an independent predictor of restenosis without an influence on the risk of subacute thrombosis.