自從主動脈瘤支架移植技術成功地被用於腹主動脈(abdominal aorta)以及降胸主動脈(descending aorta)疾病的治療上，許多研究及支架移植技術的發展便開始朝主動脈弓(aortic arch)治療去進行。然而，在主動脈弓的治療上，因為主支架會覆蓋住主動脈弓上的三條小血管而使血液無法流過，所以衍生出煙囪技術的治療方式。
在主動脈弓使用煙囪技術治療，可能會產生一些併發症，像是支架與血管壁間縫隙(Gutter)產生的內滲漏，或是煙囪支架被過度壓扁而產生的阻塞，都可能降低煙囪技術的治療效果，而不同的品牌及尺寸搭配下，會有不同的影響。
本研究對現行不同廠牌支架進行一系列力學實驗測試(徑向力測試)，並使用電腦亂層掃描做支架被壓縮比的面積量測，藉由這些體外測試，我們將可以建立各品牌尺寸的力學表現的相關知識，以提供醫師在選擇上有個良好的參考。
實驗結果發現CTAG及TAG兩個品牌會產生極大的徑向力並導致煙囪支架被壓扁，治療效果較差，且當主支架的尺寸越大時，煙囪支架的被壓縮比越大，同時支架與血管壁間縫隙(Gutter)也較小。被壓縮比及支架與血管壁間縫隙無法同時兼顧，所以判斷結果以被壓縮比越小者為佳。所以我們建議是主支架選擇Zenith TX2或Valiant，並且不要使用過大的主支架尺寸。

After the initial success achieved with the application of endovascular aortic aneurysm repair (EVAR) and thoracic endovascular aortic aneurysm repair (TEVAR) surgery for treating abdominal and descending aortic diseases, researchers have recently focused on developing new endovascular treatment approaches for aortic arch diseases. The main stent graft (MG) used to treat aneurysms in the aortic arch hinders blood flow into the vessels at the arch. Therefore, the chimney stent graft (CG) technique was developed.
The chimney technique applied for treating aneurysms in the aortic arch is associated with complications such as endoleak which caused by an excessive gutter area and stenosis caused by over compression by the CG. These complications might reduce the therapeutic effect of the chimney technique. Moreover, different combinations of various brands and sizes may exert different effects.
In this study, we tested the radial force of stents of different brands and sizes and used computed tomography (CT) to measure the area and calculate the compression ratio of CGs. These in vitro tests revealed the mechanical behavior of stents of different brands and sizes to provide surgeons with a reference for choosing the optimal combinations of stents.
We found that the brands CTAG and TAG produced the highest radial force and exhibited over compression of the chimney stent. Moreover, the gutter area decreased with increases in oversizing. Moreover, the compression ratio increased with increases in oversizing. However, the gutter area and the CG compression ratio were not considered; therefore, a stent combination with a smaller compression ratio is a more favorable choice because the function of blood flow passageway is the most important thing for this technology. This study suggests that surgeons should choose Valiant or Zenith TX2 as the MGs and not choose MGs with an excessive size.

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