Thompson Craig A, Huibregtse Barbara, Poff Bradley, Wilson Gregory J
Cardiology Section, Dartmouth Hitchcock Medical Center, Dartmouth Medical School, Lebanon, New Hampshire, USA.
Catheter Cardiovasc Interv. 2009 Apr 1;73(5):597-604. doi: 10.1002/ccd.21890.
The purpose of this study was to evaluate the time-dependent vascular and myocardial responses to a second-generation, small vessel (< or =2.5 mm) paclitaxel-eluting stent (PES) platform.
Small caliber coronary vessels present complex challenges for percutaneous coronary intervention (PCI) and are associated with lower technical success and inferior long-term efficacy. A next-generation, highly deliverable PES may improve clinical outcomes in small vessels.
Sixty single stents were implanted in noninjured coronary arteries in 30 domestic swine (one TAXUS Liberté small vessel PES (svPES) and one Liberté small vessel bare metal stent (svBMS) in each animal). Ten animals each were allocated to 30-, 90-, and 180-day follow-up groups; final quantitative angiography and necropsy were performed. Samples of myocardium, liver, and kidney were processed and evaluated for pathology. Radiography and either histopathology or scanning electron microscopy were performed on all the explanted stented vessels.
There were no stent-related deaths or downstream myocardial pathology. Both the svPES stent and its svBMS control demonstrated complete strut tissue coverage and complete endothelialization at all timepoints, and there was no evidence of macro- or microscopic thrombus or stent fracture. Medial smooth muscle cell content was markedly reduced in all the svPES groups compared with that in the svBMS controls.
The small diameter paclitaxel-eluting TAXUS Liberté stent has a safe and predictable biologic vascular response in the noninjured swine model. This device warrants further investigation targeting the currently poorly met clinical need for small vessel PCI.
本研究旨在评估第二代小血管（直径≤2.5毫米）紫杉醇洗脱支架（PES）平台随时间变化的血管和心肌反应。
小口径冠状动脉血管在经皮冠状动脉介入治疗（PCI）中面临复杂挑战，且技术成功率较低，长期疗效较差。新一代高度可输送的PES可能改善小血管的临床结局。
在30头家猪的非损伤冠状动脉中植入60个单支架（每头动物植入一个TAXUS Liberté小血管PES（svPES）和一个Liberté小血管裸金属支架（svBMS））。将10头动物分别分配到30天、90天和180天随访组；进行最终定量血管造影和尸检。对心肌、肝脏和肾脏样本进行处理并评估病理情况。对所有取出的带支架血管进行放射照相以及组织病理学或扫描电子显微镜检查。
无支架相关死亡或下游心肌病理改变。svPES支架及其svBMS对照在所有时间点均显示完全的支架小梁组织覆盖和完全内皮化，且无宏观或微观血栓或支架断裂的证据。与svBMS对照相比，所有svPES组的中膜平滑肌细胞含量均显著降低。
在非损伤猪模型中，小直径紫杉醇洗脱TAXUS Liberté支架具有安全且可预测的生物血管反应。该装置针对目前小血管PCI临床需求未得到充分满足的情况，值得进一步研究。
