D-SPECT技术简述

　　The D-SPECT is an advanced cardiac imaging technology using the well-proven cardiac single photon tracers， that utilizes a 10-times higher detector sensitivity， 5-times the spatial resolution， and 2-times the energy resolution. This cardiac imaging technology enables the generation of multiple high definition images of cardiac function including cardiac viability， ischemia， scar， innervations， as well as cardiac mechanics. All those images are generated in a fraction of the time that conventional SPECT or PET will need to generate those images; the resolution and the multiple images generated from a single D-SPECT acquisition surpasses any of the exiting cardiac imaging technology out there.

　　D-SPECT是一种先进的心脏成像技术，其采用历经充分验证的心脏单光子示踪剂，具有较高的敏感性、空间分辨率和能量分辨率，可通过提供有关心脏功能的高清图像使我们了解心肌活力、缺血、瘢痕、神经分布及心脏力学等方面的信息。与传统的SPECT或PET相比，D-SPECT能在更短时间内获取分辨率更高的多张图像。

　　助力心肌缺血评估——高速SPECT心肌灌注显像

　　The high speed myocardial perfusion imaging enables an accurate， absolute measurement of coronary flow and coronary flow reserve. The accuracy achieved with D-SPECT myocardial perfusion imaging sets a new standard for measurement of myocardial perfusion. The ease with which this information is acquired both the short duration of the D-SPECT test and from the comfortable “dental chair” like position makes it an easier experience for the patient and the medical staff. Current published data shows 94% sensitivity and 90% specificity for D-SPECT to detect significant coronary lesion on an angiogram. Cardiac SPECT imaging is well known for its negative predictive value when images indicate a low ischemia load. D-SPECT is shown by multiple clinical studies to have a higher positive， as well as negative， predictive value than conventional SPECT， PET and CT angiography. More recently， new work performed in the U.S. and Europe is comparing the predictive value of D-SPECT to FFR guided PCI procedure. Initial positive results of these studies lead us to believe that the D-SPECT pivotal study that shows the tight correlation with invasive FFR measurement will be positive and pave the way for the use of D-SPECT as the gatekeeper of the catheterization laboratory.

　　高速心肌灌注显像能在短时间内、在更舒适的条件下、更准确地测量冠状动脉（简称冠脉）血流及冠脉血流储备的绝对值，为医生及患者带来更好的体验。近期发表的数据显示，其识别冠脉造影所示的明显冠脉病变的敏感性及特异性分别为94%和90%。与传统的SPECT、PET及CT造影相比，DSPECT对冠脉疾病具有更高的阳性及阴性预测价值。近期美国及欧洲正在开展相关工作就DSPECT与FFR指导下的PCI之预后进行对比分析，并取得了初步的阳性结果，为DSPECT在导管室中的广泛应用铺平了道路。

　　应用现状解析及前景展望

　　D-SPECT is currently used as a standard screening test for detection of patients with coronary disease， as well as a screening test for ruling out the presence of coronary disease. D-SPECT advanced imaging is used to determine absolute coronary flow and coronary flow reserve – the current gold-standard for detecting functionally significant coronary disease that requires intervention.

　　D-SPECT was used in more than 500，000 patients in the U.S. over the last few years. The ample amount of data acquired in each study and our growing positive experience with the D-SPECT technology lead me to believe that D-SPECT will become the standard of care for selecting patients for interventional procedure because of its high sensitivity， specificity and accuracy of identifying， and quantifying the exact coronary bed that has a functionally significant coronary disease. Moreover， D-SPECT’s unique ability to image viability， ischemia and cardiac innervation will enable the cardiologist better insight into the specific cardiac pathology of their patient. This “holistic” view on cardiac pathology has already made an impact on a novel certain intervention procedure that harnesses the new information regarding regional cardiac denervation with respect to its impact on sudden cardiac death.

　　There are more than 25，000 SPECT machines around the world， but there are less than 200 cardiac DSPECT. The conventional model of delivering D-SPECT as a capital equipment to hospitals slows the adoption by definition. New models that enable physicians have access to D-SPECT procedures， without having them to go through the step of acquiring a capital equipment first， may accelerate the expected adoption.

　　目前，D-SPECT心脏机已经被用于冠脉疾病的筛查与排除。过去几年中，其已成功在500 000余例患者中应用，并积累了大量的研究数据及实践应用经验。我们有理由相信，以其良好的敏感性、特异性、准确性以及能对冠脉血管床准确量化、反映心肌缺血及心脏神经支配的独特优势，这一新技术将有助于帮助心脏病学专家更好地了解患者心脏的整体病理改变，并对心脏去神经治疗的新兴治疗方法提供更好的安全保障。但是，目前D-SEPCT心脏机尚不足200台，传统的固定资产购置流程在一定程度上延缓了其在各医院的推广应用，亟需有更好的方法能让医生有更多机会应用D-SPECT这一新技术。