Stark Madeline, Suresh Adithya, Alexander Jason, Cragg Andrew
Division of Vascular Surgery, Minneapolis Heart Institute Foundation, Abbott Northwestern Hospital, Minneapolis, MN.
Division of Vascular Surgery, Minneapolis Heart Institute Foundation, Abbott Northwestern Hospital, Minneapolis, MN.
Ann Vasc Surg. 2014 May;28(4):808-15. doi: 10.1016/j.avsg.2013.06.039. Epub 2013 Nov 5.
A major factor in the selection of patients for endovascular aneurysm repair (EVAR) is the character of the aortic neck, and studies suggest that many patients are treated outside of the instructions for use (IFU) criteria. By analyzing aortic neck morphology, we hope to identify factors that may influence decision making about the use of fenestrated endografts as an alternative to extending the neck limitations of traditional endografts.
A retrospective analysis was completed on 111 patients who underwent computed tomography angiography (CTA) scans between May 1, 2009 and January 3, 2011 for the evaluation of abdominal aortic aneurysm (AAA). Individual characteristics of neck and aneurysm morphology were analyzed to establish whether certain factors determined suitability for EVAR with traditional nonfenestrated endografts. In considering augmented neck lengths (ANL), anatomic measurements of distance from the start of aortic dilatation to the lowest renal artery (LRA) and highest renal artery (HRA) were analyzed. Measurements were analyzed using Stata software (version 11.2; StataCorp, College Station, TX).
There were 86 men and 25 women in the patient population, with an average age of 72.9 years. In 46 patients, the proximal neck length was <15 mm, with 26 patients having neck lengths <10 mm. There was a negative relationship between AAA maximum diameter and proximal neck length (rs = -0.2237; P = 0.018), indicating that as aneurysm size increases, proximal neck length decreases. There was a significant correlation between proximal neck length and proximal neck diameter (rs = -0.2585; P = 0.006) and between proximal neck length and angle (rs = -0.2355; P = 0.013), and between proximal neck diameter and right iliac maximum diameter (rs = 0.2329; P = 0.014). Using fenestration to place an endograft above the LRA would create an ANL of >15 mm in 20 of 40 patients with aortic necks deemed too short to be eligible for EVAR using conventional infrarenal graft positioning. Extending the graft above the HRA would create an ANL of >15 mm in 36 of 40 patients.
In this study, 41% of patients presented with neck lengths outside that of the traditional IFU for most aortic endografts. While there was wide variation from patient to patient, there was a general correlation between increasing AAA size and aneurysms that have shorter, wider, and more angulated proximal necks. Fenestration of even 1 renal artery could substantially increase the ANL. Additional study is warranted to determine if an increase in ANL in patients with otherwise short necks will positively impact long-term EVAR outcomes.
选择患者进行血管内动脉瘤修复术（EVAR）的一个主要因素是主动脉颈部的特征，研究表明许多患者是在使用说明书（IFU）标准之外接受治疗的。通过分析主动脉颈部形态，我们希望确定可能影响关于使用开窗型血管内移植物替代扩大传统血管内移植物颈部限制的决策的因素。
对2009年5月1日至2011年1月3日期间接受计算机断层扫描血管造影（CTA）扫描以评估腹主动脉瘤（AAA）的111例患者进行了回顾性分析。分析颈部和动脉瘤形态的个体特征，以确定某些因素是否决定了使用传统非开窗型血管内移植物进行EVAR的适用性。在考虑增加的颈部长度（ANL）时，分析了从主动脉扩张开始到最低肾动脉（LRA）和最高肾动脉（HRA）的距离的解剖学测量值。使用Stata软件（版本11.2；StataCorp，大学城，德克萨斯州）进行测量分析。
患者群体中有86名男性和25名女性，平均年龄为72.9岁。在46例患者中，近端颈部长度<15mm，其中26例患者颈部长度<10mm。AAA最大直径与近端颈部长度之间存在负相关（rs = -0.2237；P = 0.018），表明随着动脉瘤大小增加，近端颈部长度减小。近端颈部长度与近端颈部直径之间（rs = -0.2585；P = 0.006）、近端颈部长度与角度之间（rs = -0.2355；P = 0.013）以及近端颈部直径与右髂总动脉最大直径之间（rs = 0.2329；P = 0.014）存在显著相关性。对于40例被认为颈部过短而不符合使用传统肾下型移植物定位进行EVAR标准的患者，使用开窗技术将血管内移植物放置在LRA上方，将使40例患者中的20例ANL>15mm。将移植物延伸至HRA上方将使40例患者中的36例ANL>15mm。
在本研究中，41%的患者呈现出的颈部长度超出了大多数主动脉血管内移植物的传统IFU范围。虽然患者之间存在很大差异，但AAA大小增加与近端颈部较短、较宽且角度更大的动脉瘤之间存在一般相关性。即使对1条肾动脉进行开窗也可显著增加ANL。有必要进行进一步研究以确定颈部较短的患者中ANL增加是否会对EVAR长期结果产生积极影响。
