小林 欣夫

The intrinsic characteristics of a stent including stent length may affect both procedural success and long-term outcome. The present study evaluated the immediate and follow-up results after implantation of the short and long NIR stent and compared these results with the Palmaz-Schatz stent. Between July 1995 and December 1996, stenting with a 16-mm NIR stent (NIR-16), a 32-mm NIR stent (NIR-32), or a Palmaz-Schatz stent (88) was performed in 68, 57, and 155 lesions, respectively. There were no significant differences in the incidences of delivery failure (PS, 2.6%: NIR-16, 4.4%; NIR-32, 5.3%; p = NS) and procedural success (PS, 92%; NIR-16, 93%; NIR-32, 93%; p NS) among the 3 groups. The reference vessel diameter was smaller in lesions with a 32-mm NIR stent than in those with a Palmaz-Schatz stent (PS, 3.14 +/- 0.58, NIR-16, 3.00 +/- 0.50; NIR-32, 2.90 +/- 0.47 mm; p <0.05). The lesion length was longer in lesions with a 32-mm NIR stent than in those with a Palmaz-Schatz or a 16-mm NIR stent (PS, 8.9 +/- 5.0; NIR-16, 11.0 +/- 4.1; NIR-32 26.1 +/- 9.7 mm; p <0.01). After the procedure, the lesions with a 32-mm NIR stent had a smaller minimal lumen diameter than those with a Palmaz-Schatz stent (PS, 3.17 +/- 0.61; NIR-16, 2.99 +/- 0.51; NIR-32, 2.89 +/- 0.49 mm; p <0.01). At follow-vp, a smaller minimal lumen diameter was observed in lesions with a 32-mm NIR stent than in those with a Palmaz-Schatz or a 16-mm NIR stent (PS, 2.32 +/- 0.98; NIR-16, 2.25 +/- 0.80; NIR-32, 1.68 +/- 0.79 mm; p <0.01). Restenosis rates were 16.5% in lesions with a Palmaz-Schatz stent, 13.3% in those with a 16-mm NIR stent, and 47.4% in those with a 32-mm NIR stent (p <0.01). Although stent delivery and procedural success of a long NIR stent were acceptable, the restenosis rate of a long NIR stent was high compared with a short NIR stent or a Palmaz-Schatz stent. (C) 1999 by Excerpta Medico, Inc.

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 less than or equal to 20 mm; 2) group II (n = 278): stented segment length >20 but less than or equal to 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. (J Am Coll Cardiol 1999; 34:651-9) (C) 1999 by the American College of Cardiology.

The present study evaluated the acute and follow-up results of stenting following aggressive rotational atherectomy compared with stenting following less aggressive rotational atherectomy. Recent work has demonstrated that stenting following rotational atherectomy is a promising strategy for complex and calcified lesions. However, there is little information available regarding the optimal procedural technique of rotational atherectomy to be employed before stent implantation, Between May 1995 and February 1997, 162 lesions in 126 patients were stented following rotational atherectomy because of the presence of severe calcification on fluoroscopy or intravascular ultrasound (95%), The lesions were divided as to whether aggressive rotational atherectomy was performed or not, Aggressive rotational atherectomy, defined as the use of a final burr size greater than or equal to 2.25 mm and/or final burr/vessel ratio greater than or equal to 0.8, was performed in 56 lesions. A less aggressive rotational atherectomy strategy was performed in 106 lesions. Procedural Q-wave (8.9% vs, 1.9%, P < 0.05) and non-Q-wave (11% vs. 1.9%, P < 0.05) myocardial infarctions were observed more frequently after aggressive rotational atherectomy; there was no significant difference in the incidence of other procedural complications. Although there was no significant difference in minimal lumen diameter after the procedure (3.11 +/- 0.68 vs. 2.99 +/- 0.48 mm, NS), at follow-up a greater minimal lumen diameter was observed in the lesions treated with aggressive rotational atherectomy compared to those treated with less aggressive rotational atherectomy (2.12 +/- 1.31 vs. 1.56 +/- 0.89 mm, P < 0.01). Restenosis rates were 50.0% in the lesions treated without aggressive rotational atherectomy and 30.9% in those treated with aggressive rotational atherectomy (P < 0.05), There was no significant difference in the incidence of restenosis with a focal pattern between the two groups (25.0% vs. 21.4%, NS), In contrast, restenosis with a diffuse pattern was lower in lesions treated with aggressive rotational atherectomy than in those without aggressive rotational atherectomy (9.5% vs. 25.0%, P < 0.05), Aggressive rotational atherectomy followed by stenting is a promising strategy to reduce the restenosis rate in calcified lesions. However, the aggressive strategy is associated with an increased risk of procedural myocardial infarction. (C) 1999 Wiley-Liss, Inc.

The present study evaluated the acute and follow-up results of stenting following aggressive rotational atherectomy compared with stenting following less aggressive rotational atherectomy. Recent work has demonstrated that stenting following rotational atherectomy is a promising strategy for complex and calcified lesions. However, there is little information available regarding the optimal procedural technique of rotational atherectomy to be employed before stent implantation, Between May 1995 and February 1997, 162 lesions in 126 patients were stented following rotational atherectomy because of the presence of severe calcification on fluoroscopy or intravascular ultrasound (95%), The lesions were divided as to whether aggressive rotational atherectomy was performed or not, Aggressive rotational atherectomy, defined as the use of a final burr size greater than or equal to 2.25 mm and/or final burr/vessel ratio greater than or equal to 0.8, was performed in 56 lesions. A less aggressive rotational atherectomy strategy was performed in 106 lesions. Procedural Q-wave (8.9% vs, 1.9%, P < 0.05) and non-Q-wave (11% vs. 1.9%, P < 0.05) myocardial infarctions were observed more frequently after aggressive rotational atherectomy; there was no significant difference in the incidence of other procedural complications. Although there was no significant difference in minimal lumen diameter after the procedure (3.11 +/- 0.68 vs. 2.99 +/- 0.48 mm, NS), at follow-up a greater minimal lumen diameter was observed in the lesions treated with aggressive rotational atherectomy compared to those treated with less aggressive rotational atherectomy (2.12 +/- 1.31 vs. 1.56 +/- 0.89 mm, P < 0.01). Restenosis rates were 50.0% in the lesions treated without aggressive rotational atherectomy and 30.9% in those treated with aggressive rotational atherectomy (P < 0.05), There was no significant difference in the incidence of restenosis with a focal pattern between the two groups (25.0% vs. 21.4%, NS), In contrast, restenosis with a diffuse pattern was lower in lesions treated with aggressive rotational atherectomy than in those without aggressive rotational atherectomy (9.5% vs. 25.0%, P < 0.05), Aggressive rotational atherectomy followed by stenting is a promising strategy to reduce the restenosis rate in calcified lesions. However, the aggressive strategy is associated with an increased risk of procedural myocardial infarction. (C) 1999 Wiley-Liss, Inc.