Improved long-term biocompatibility of coronary stents by plasma coating process

摘要药物洗脱支架（DES）因其比裸金属支架（BMS）具有更好的控制再狭窄的能力而被广泛应用于心脏病患者的治疗。然而，有报道称使用DES治疗的患者晚期支架血栓形成的严重不良后果，即使发生率很低，也会导致致命性心脏病发作和死亡。因此，为了安全有效的临床使用，冠状动脉支架需要在其表面具有更好的生物相容性，除了抑制细胞增殖从而减缓支架周围组织的愈合外，还需要提供足够的抗血栓性。Nanova, Inc.正在开发一种新型的高抗血栓涂层在金属生物材料的表面，冠状动脉支架的制造。低温等离子体工艺是一种环保技术，用于沉积超薄（纳米级）但连续的涂层层，足以产生所需的耐磨性，并固定在随后的等离子体表面处理中产生的生物活性官能团，以防止血凝块和再狭窄，但薄到足以允许支架在输送到患者体内时膨胀而不会破裂。在这一创新研究项目中获得的知识也将有利于研究和开发改善其他植入式医疗设备的生物相容性，如起搏器、脉冲发生器、心脏除颤器和生物传感器。

DESCRIPTION (provided by applicant): Improved long-term biocompatibility of coronary stents by plasma coating process Abstract Drug-eluting stents (DES) have been widely used to treat patients of cardiac disease due to their better ability to control restenosis than bare metal stents (BMS). However, a serious adverse outcome of late stent thrombosis in patients treated with DES has been reported, which leads to fatal heart attack and death even though it occurs at low rate. Thus, for safe and effective clinical use, a coronary stent needs to have better biocompatibility on its surface that will provide sufficient thrombo-resistance in addition to inhibiting cell proliferation thereby slowing down healing of tissues around the stent. Nanova, Inc. is developing a novel coating layer of high thrombo-resistance on the surface of metallic biomaterials of which coronary stents are made. An environmentally benign technology, low temperature plasma process is used to deposit an ultra-thin (nano-scale) but continuous layer of coating, sufficient to generate desired abrasion resistance and immobilize the bioactive functional groups created in the subsequent plasma surface treatment to prevent blood clots and restenosis, but thin enough to allow for stent expansion without cracking when delivered into patients. The knowledge gained in this innovative research project will also benefit research and development for improved biocompatibility in other implantable medical devices such as pacemakers, pulse generators, cardiac defibrillators and bio-sensors.