NONINVASIVE EVALUATION OF CORONARY BYPASS GRAFT PATENCY

动脉冠状动脉搭桥术是一种常用的手术方式。 冠心病管理中的治疗性干预 疾病。然而，众所周知，这种情况的明确性 移植物可以随着时间的推移而逐渐减少。最终的 确认移植物通畅的方法是选择性血管造影术。这 手术费用昂贵，具有侵入性，并带有一定程度的 发病率和死亡率。另一种非侵入性治疗方法 评估移植物的通畅性包括铊扫描，多普勒- ECHO、IV数字减影血管造影术和计算机 体层摄影(CT)。在这些替代方案中，只有CT实现了 足够的准确性，足以保证继续考虑作为 血管造影术的非侵入性替代。尽管如此，CT 这些方法有些昂贵，会产生明显的辐射 对心脏的剂量，如果为假，则需要显著的学习曲线 应避免负面和假阳性评价。 这项建议的目的是开发一种新的非侵入性 评估移植物通畅性的技术，但这是一种 价格低廉，只需CT扫描辐射剂量的十分之一，以及 避免了CT技术固有的移植物识别问题 通过使用一种将身份识别与移植分开的程序 评估。这项新技术将使用小型专用的两个- 适用于连接到导管的探测器X射线扫描系统 实验室透视设备或小型便携式X射线发生器。这 扫描系统将使用x射线散射和x射线诱导 荧光技术在搭桥术中的定位和评价 分别进行了分析。这项提案的目的是设计、建造、 测试并验证这一新系统。测试和验证将是 在机械模型、动物模型(犬类)和 人类。

Aortocoronary bypass graft surgery is a frequently employed therapeutic intervention in the management of coronary heart disease. It is well known, however, that the patency of such grafts can decrease progressively over time. The definitive confirmation of a graft's patency is selective angiography. This procedure is costly, invasive, and carries some degree of morbidity and mortality. Alternative noninvasive methods for evaluating graft patency have included thallium scans, doppler- echo, IV digital subtraction angiography, and computed tomography (CT). Of these alternatives only CT has achieved sufficient accuracy to warrant continued consideration as a noninvasive alternative to angiography. Nevertheless, CT methods are somewhat expensive, deliver an appreciable radiation dose to the heart, and require a significant learning curve if false negative and false positive evaluations are to be avoided. It is the aim of this proposal to develop a new noninvasive technique for the evaluation of graft patency, but one that is inexpensive, requires 1/10 of the radiation dose of a CT scan, and avoids problems of graft identification inherent in CT techniques by using a procedure that separates identification from graft evaluation. This new technique will use a small dedicated two- detector x-ray scanning system suitable for attachment to a cath lab fluoroscopic unit or a small portable x-ray generator. This scanning system will use x-ray scatter and x-ray induced fluorescence for the location and evaluation of by-pass grafts respectively. The aim of this proposal is to design, construct, test, and validate this new system. Testing and validation will be performed on mechanical models, animal models (canine), and humans.