Lau K W, He Q, Ding Z P, Johan A
Singapore Heart Centre, Singapore.
Clin Cardiol. 1997 Aug;20(8):711-6. doi: 10.1002/clc.4960200809.
Increased operator experience, greater insight in stent deployment techniques, and improved poststent medication regimen have significantly reduced the risk of thrombotic stent closure following stent placement in large coronary arteries (> or = 3.0 mm in diameter). Whether equally favorable results are afforded by stent placement in small vessels (< 3.0 mm), however, remains unclear. Accordingly, the aim of this study was the specific examination of the risk of stent placement in small native coronary vessels, using stent deployment technique consisting of supplementary dilatations with larger balloons or high-pressure inflations, and aggressive aspirin-ticlopidine and short-term oral anticoagulation poststent therapy.
Forty-seven balloon-expandable stents (20 Gianturco-Roubin, 21 NIR, 6 Palmaz-Schatz) were successfully implanted without intravascular guidance in 45 native coronary arteries (mean reference diameter of 2.5 mm) in 44 consecutive patients (31 men, 13 men), the majority of whom (87%) were stented for the treatment of failed or suboptimal balloon angioplasty outcome.
Successful stent placement reduced the lesion diameter stenosis from 91 +/- 9% to 3 +/- 7% (p = 0.0001). There were no early stent thrombosis or major cardiovascular events prior to hospital discharge. During a 12-month follow-up period, most patients remained symptomatically improved and no myocardial infarction, stroke, or death was observed. Five-month angiographic reassessment revealed an in-stent restenosis rate of 41%, which was higher in vessels < or = 2.5 mm in size (47 vs. 33% for vessels > 2.5 mm, p = 0.2747).
In selected patients with small native coronary vessels < 3.0 mm in diameter, angiography-guided optimal stent placement is associated with a low risk of stent thrombosis and bleeding complications. However, the in-stent restenosis rate is high with the stents used in this study.
术者经验的增加、对支架置入技术更深入的了解以及支架置入后药物治疗方案的改进，已显著降低了在大冠状动脉（直径≥3.0mm）中置入支架后血栓形成导致支架闭塞的风险。然而，在小血管（<3.0mm）中置入支架是否能获得同样良好的效果仍不清楚。因此，本研究的目的是通过使用由更大球囊辅助扩张或高压充盈以及积极的阿司匹林-噻氯匹定和支架置入后短期口服抗凝治疗组成的支架置入技术，专门检查在小的自身冠状动脉血管中置入支架的风险。
在44例连续患者（31例男性，13例女性）的45条自身冠状动脉（平均参考直径2.5mm）中，在无血管内引导的情况下成功植入了47个球囊扩张支架（20个Gianturco-Roubin支架、21个NIR支架、6个Palmaz-Schatz支架），其中大多数患者（87%）因球囊血管成形术失败或效果欠佳而接受支架置入治疗。
成功置入支架使病变直径狭窄率从91±9%降至3±7%（p = 0.0001）。出院前无早期支架血栓形成或重大心血管事件发生。在12个月的随访期内，大多数患者症状持续改善，未观察到心肌梗死、中风或死亡。5个月时的血管造影复查显示支架内再狭窄率为41%，在直径≤2.5mm的血管中更高（直径>2.5mm的血管为33% vs. 47%，p = 0.2747）。
在选定的直径<3.0mm的小自身冠状动脉血管患者中，血管造影引导下的最佳支架置入与较低的支架血栓形成和出血并发症风险相关。然而，本研究中使用的支架的支架内再狭窄率较高。
