2016-08-012024-05-14https://scholars.lib.ntu.edu.tw/handle/123456789/657175摘要：傳統診斷心血管疾病的工具包括運動心電圖，催迫性心臟超音波或傳統鉈201 單光子心肌灌注掃瞄等非侵襲性檢查對於瀰漫性冠狀動脈病變或心臟移植後血管病變的診斷率並不理想。而本院心臟移植團隊證實動態性13N-ammonia 正子心臟掃描合併藥物催迫試驗測量到的冠狀動脈血流變化及內皮功能之參數，可以更有效率的評估心臟移植後血管病變（myocardial perfusion reserve 與intravascularultrasound findings 呈現負相關，發表於：J Nucl Med 2010 Jun; 51(6): 906-12 及Society of NuclearMedicine 2012 Annual Meeting, Jun. 9-13. 2012, Miami, FL, USA）。但13N-ammonia 正子掃描須配有cyclotron 的醫院才能生產此類短半衰期的正子藥物 (13N 半衰期僅9.8 分鐘)，因此製造成本昂貴、藥物取得不易。發展出新的核醫心血管影像技術，更有效率的追蹤心臟移植後血管內皮功能變化及評估各種治療後的反應，應有其迫切性及必要性。傳統的單光子掃瞄僅能測量冠狀動脈血流變化（非定量），無法提供內皮功能變化指標，對於瀰漫性冠狀動脈病變或心臟移植後血管病變的診斷率較差。近年來本院購置的新型心臟專用快速半導體單光子斷層掃描儀，與傳統的碘化鈉掃描儀相比，有較高的靈敏度，可降低同位素藥物注射量及掃描時間，仍保有良好的診斷率及成功克服在傳統單光子掃描儀無法做動態影像的限制。在此掃描儀上可利用動態影像擷取技術合併藥物催迫試驗訂量心肌血流量(myocardial blow flow)及灌流儲備分率（myocardial flow reserve），有機會提高瀰漫性冠狀動脈病變和心臟移植後血管病變的診斷率。本計畫為兩年期前瞻性研究，預計納入70 位接受心臟移植患者。本研究主旨為評估在接受心臟移植後的病患利用新型心臟專用快速半導體單光子斷層掃描儀進行動態性鉈201 單光子心肌灌注掃瞄的可行性，計算出的心肌血流量(myocardial blow flow)及灌流儲備分率（myocardial flow reserve），與動態性13N-ammonia 正子心臟掃描所得之分析結果做比較。矣獲得初步研究成果後，評估藉此新技術在取代動態性13N-ammonia 正子心臟掃描來追蹤心臟移植後血管病變之可行性。同時希望利用各種功能性影像參數篩檢出高危險群無症狀個案之早期心臟移植後血管病變，早期進行介入性治療，改善病患存活預後。<br> Abstract: Although myocardial perfusion imaging (MPI) has been used extensively in the management ofcoronary artery disease (CAD), cardiac allograft vasculopathy (CAV) remained diagnostic challenges due toglobal reduction in myocardial perfusion (balanced ischemia). Quantification of myocardial perfusion reserve(MPR) or coronary flow reserve has emerged as an important index to improve diagnosis and riskstratification in CAD. The National Taiwan University Hospital (NTUH) Transplantation Team had validatedthe use of 13N-ammonia PET in the assessment of MPR in angiographically normal cardiac transplantrecipients as a reliable marker of CAV progression: MFR inversely correlates with intravascular ultrasoundmeasurements (J Nucl Med 2010 Jun; 51(6): 906-12 及Society of Nuclear Medicine 2012 Annual Meeting,Jun. 9-13. 2012, Miami, FL, USA). Still, 13N-ammonia can only be produced by a PET center equipped withan on-site cyclotron due to its short half-life (9.8 minutes) with high start-up costs, and the low patientthroughput (1 to 2 patients in a morning) and long study time (patients are required to wait on the table forthe production of tracer) greatly limits its use clinically. SPECT imaging still remains the clinical standard forMPI worldwide. In recent years, NTUH bought a new generation of ultra-fast SPECT cardiac cameras withsemiconductor cadmium-zinc-telluride (CZT) detector technology. This new high efficiency cardiac cameraprovides excellent image quality, shorten image time, reduce radiation exposure, and can overcome thedifficulty of achieving tomographic dynamic acquisitions using classic Anger cameras. Quantification ofMPR becomes feasible through multiframe dynamic reconstructions with sufficient temporal resolution,thereby has the potential to increase diagnostic sensitivity in CAV.This is a 2-year prospective study:1. To evaluate the feasibility of rest flow, stress flow, and MPR estimation from dynamic SPECT MPIkinetic analysis using the high efficiency cardiac CZT camera in heart-transplanted patients,2. To correlate flow parameters and MPR obtained from dynamic SPECT MPI with those calculatedfrom 13N-ammonia PET,3. To incorporate flow, MPR, ischemia information, and ventricular function obtained from bothmodalities and correlate with information derived from coronary angiography, intravascularultrasound, and endomyocardial biopsy results,4. To determine if MPR and flow data from dynamic SPECT MPI can act as robust markers forreliable late outcomes of CAV,5. To identify the subset of heart-transplanted patients who benefit from mechanical revascularizationin addition to optimal medical therapy,6. To evaluate the feasibility of replacing 13N-ammonia PET with dynamic SPECT MPI, since MPI isuniversal in availability and applicable at any time in the post-transplantation process.心臟移植後血管病變快速半導體單光子斷層掃描儀心肌血流量灌流儲備分率cardiac allograft vasculopathyCZT cameraabsolute myocardial blood flowmyocardial perfusion reserve