動脈總順應性（Total Arterial Compliance，TAC)是指全身動脈順應性之總和， 可用來評估全身動脈血管硬化程度，臨床上大多以脈波傳導速率（Pulse Wave Velocity，PWV)做為動脈總順應性之相關參考指標。本研究的目的是觀察主動脈 在心週期下的容積變化，使用3D心臟電腦斷層影像（Computed Tomography，CT ) 來評估動脈PWV。利用自行開發的影像處理程式重建心臟DICOM影像，分成10 個時序來完成3D心臟模型並計算感興趣區域内（ROI)的容積。實驗部分利用 15位受測者的3D心臟電腦斷層影像計算主動脈流量容積，其結果在68.91到97.54 ml之間，這些容積數據與利用左心室造影算出的心輸出量具有良好的正相關性 (主動脈截面積流量=1.07*左心室心輸出量-4.082 m，R2 = 0.968，p < 0.01 )PWV 的計算是同時量測兩個不同位置的血壓波形時間差（AS)及兩點間距離（AD)之 比值（Ad/As)，本實驗選擇在一個心週期中，每個切面下的最大容積峰值，得知 最大峰值的時間差與切面差，經由這兩個參數去評估PWV。得出的PWV值介於0.714到1.548 m/s之間。結果顯示本研究所評估的脈搏傳導速率（PWV)與動脈 順應性（TAC)相關性分析結果成正相關（r = 0.666，p < 0.01 )、與血管擴張性相 關性結果成負相關（r = -0.8138，p < 0.01)。因此本研究提供一套利用3D心臟電 腦斷層影像中藉由估算主動脈脈搏傳導速度（PWV)作為指標，來評估動脈血管硬化。

Recent studies have shown that patients who have atherosclerosis would increase the risk of cardiovascular disease directly or indirectly. Total arterial compliance (TAC) is defined as the sum of systemic arterial compliance to estimate the feature of atherosclerosis while Pulse wave velocity (PWV) is an index for clinically assessing the level of artery stiffness in TAC. The purpose of this study is to investigate the volume change in the aortic heart cycle to evaluate the arterial PWV by using 3D cardiac computed tomography images. In this research, Cardiac DICOM images are reconstructed by a self-developed image processing program into 10 frames of 3D cardiac model to inspect data specified and calculated in the DICOM data set for the volume at ROI. In experiment, fifteen subjects’ 3D CT cardiograms were collected to calculate the aortic flows, which ranged from 68.91 to 97.54 ml. The data well-correlated with the cardio outputs from the Left Ventricular (LV) image (Aortic Flow = 1.07*Cardio 0utput-4.082 ml, R2 = 0.968, p < 0.01). And the PWV was calculated from variation of distance divided by the time difference (Ad/As). That was to select the max distention from aortic slices and the distance between the slice and the time difference calculated with the results shown PWVs ranging from 0.714 to 1.548 m/s. Furthermore, the data positively correlated to Total arterial compliance calculated at the aortic root (r = 0.666, p < 0.01). And, the PWV negatively correlated to the distention of aorta (r = -0.8138, p < 0.01). Therefore, this derived methodology could be used to index and calculate PWV from 3D CT cardiac image in evaluating arterial stiffness.