Foley J B, Brown R I, Penn I M
Victoria Hospital, University of Western Ontario, London, Canada.
Coron Artery Dis. 1994 Jan;5(1):73-80. doi: 10.1097/00019501-199401000-00010.
Restenosis is the main limitation of long-term success after coronary angioplasty. Intracoronary stent implantation may reduce restenosis by producing a larger initial lumen and eliminating recoil. The objective of this study was to determine the frequency of and features associated with restenosis after elective single Palmaz-Schatz stent implantation in de-novo lesions in native vessels.
Eighty consecutive patients were studied. Angiographic follow-up was performed in 79 out of 80 (99%) 6.5 +/- 3.4 months after the procedure. Angiographic measurements were performed using an automated computerized quantitative angiographic analysis system.
Restenosis (> or = 50% stenosis) at follow-up occurred in 26 out of 79 patients (33%). The frequency of complex lesion morphology was higher (50% versus 19% American College of Cardiology/American Heart Association classification B2; P = 0.005), the reference vessel diameter larger (3.0 +/- 0.5 mm versus 2.8 +/- 0.6 mm, P = 0.049), and the lesion length longer (10.9 +/- 3.5 mm versus 8.5 +/- 3.5 mm, P = 0.009) in the restenosis group compared with the non-restenosis group. The population was divided into three groups according to the reference vessel diameter: (1) greater than 3.0 mm (n = 27), (2) 2.5-3.0 mm (n = 29), and (3) less than 2.5 mm (n = 22). One patient was excluded from this subgroup analysis because of difficulty in determining the reference vessel diameter before the procedure. The restenosis rates were 52%, 37%, and 11%, respectively, for the three groups (P = 0.02). The relative acute gain was greater in the smaller vessels, (0.66 in the < 2.5 mm vessels, 0.53 in the 2.5-3.0 mm vessels, and 0.48 in the > 3.0 mm vessels; P = 0.006). This was associated with a relative oversizing of the final stent balloon in the smaller vessels (balloon-to-vessel ratio of 1.33 in the vessels < 2.5 mm diameter, 1.16 in the 2.5-3.0 mm vessels, and 0.98 in the > 3.0 mm vessels; P = 0.001).
The frequency of restenosis in single electively implanted Palmaz-Schatz stents in de-novo lesions in native vessels was 33%. The degree of restenosis was lower in smaller vessels, in which a better initial result was associated with relative oversizing of the final stent balloon. More aggressive dilation within the stented segment may result in a lower restenosis rate.
再狭窄是冠状动脉血管成形术后长期成功的主要限制因素。冠状动脉内支架植入术可通过产生更大的初始管腔和消除弹性回缩来降低再狭窄率。本研究的目的是确定在天然血管的原发性病变中选择性植入单个帕尔马兹-沙茨支架后再狭窄的发生率及相关特征。
对80例连续患者进行研究。80例患者中有79例（99%）在术后6.5±3.4个月进行了血管造影随访。血管造影测量使用自动计算机化定量血管造影分析系统进行。
79例患者中有26例（33%）在随访时出现再狭窄（狭窄≥50%）。与无再狭窄组相比，再狭窄组复杂病变形态的发生率更高（50%对美国心脏病学会/美国心脏协会分类B2的19%；P=0.005），参考血管直径更大（3.0±0.5mm对2.8±0.6mm，P=0.049），病变长度更长（10.9±3.5mm对8.5±3.5mm，P=0.009）。根据参考血管直径将患者分为三组：（1）大于3.0mm（n=27），（2）2.5 - 3.0mm（n=29），（3）小于2.5mm（n=22）。1例患者因术前难以确定参考血管直径而被排除在该亚组分析之外。三组的再狭窄率分别为52%、37%和11%（P=0.02）。较小血管的相对急性增益更大（直径<2.5mm的血管为0.66，2.5 - 3.0mm的血管为0.53，>3.0mm的血管为0.48；P=0.006）。这与较小血管中最终支架球囊的相对尺寸过大有关（直径<2.5mm的血管球囊与血管比率为1.33，2.5 - 3.0mm的血管为1.16，>3.0mm的血管为0.98；P=0.001）。
在天然血管的原发性病变中选择性植入单个帕尔马兹-沙茨支架的再狭窄发生率为33%。较小血管中的再狭窄程度较低，在这些血管中较好的初始结果与最终支架球囊的相对尺寸过大有关。在支架段内进行更积极的扩张可能会导致更低的再狭窄率。
