Falkensammer Juergen, Oldenburg W Andrew, Biebl Matthias, Hugl Beate, Hakaim Albert G, Crook Julia E, Berland Todd L, Paz-Fumagalli Ricardo
Section of Vascular Surgery, Mayo Clinic Jacksonville, Jacksonville, FL 32224, USA.
J Vasc Surg. 2007 May;45(5):900-5. doi: 10.1016/j.jvs.2007.01.015.
Proximal endovascular aortic graft fixation and maintenance of hemostatic seal depends on the long-term stability of the aortic neck. Previous investigations of aortic neck dilation mostly focused on the infrarenal aortic diameter. Fenestrated and branched stent grafts facilitate suprarenal graft fixation and may thereby improve the long-term integrity of the aortic attachment site. For these devices, the natural history of the suprarenal aortic segment is also of interest. We investigated the natural history of the supra- and infrarenal aortic segment after open abdominal aortic aneurysm (AAA) repair.
For this retrospective analysis, we reviewed the preoperative and the initial postoperative as well as the most recent CT series that were obtained from 52 patients undergoing conventional repair of an infrarenal abdominal aortic aneurysm between January 1998 and December 2002. Measurements were performed using electronic calipers on a "split screen", allowing direct comparison of subsequent CT series at corresponding levels along the vessel. Main outcome measures were changes in postoperative measures of the supra- and infrarenal aortic diameters.
The first postoperative exam was at a mean (+/-SD) of 7.0 +/- 3.5 months, and the final exams were at 44.4 +/- 21 months. Over this time period, the estimated rate of change in suprarenal diameter was 0.18 mm/ y with 95% confidence interval (CI) from 0.08 to 0.27. The estimated rate of change for the infrarenal diameter was 0.16 (95% CI: 0.05 to 0.27). A clinically relevant diameter increase of >or=3 mm was observed in seven patients (13%). There was evidence of larger diameter increases associated with larger AAA diameters (P = .003 and <.001 for suprarenal and infrarenal diameters), an inverted funnel shape (P = .002 and <.001), and marginal evidence of association with a history of inguinal hernia (P = .043 and .066).
Although there is statistically significant evidence of increases in the supra- and infrarenal aortic diameters after conventional AAA repair, mean annual increases tended to be small and clinically relevant increases of 3 mm or more were observed in only a small proportion of cases.
近端血管内主动脉移植物的固定及止血密封的维持取决于主动脉颈部的长期稳定性。既往对主动脉颈部扩张的研究大多集中于肾下腹主动脉直径。开窗和分支型支架移植物有助于肾上移植物的固定，从而可能改善主动脉附着部位的长期完整性。对于这些装置，肾上主动脉节段的自然病程也备受关注。我们研究了开放性腹主动脉瘤（AAA）修复术后肾上和肾下主动脉节段的自然病程。
对于这项回顾性分析，我们回顾了1998年1月至2002年12月期间52例行肾下腹主动脉瘤传统修复术患者的术前、术后初始及最近的CT系列资料。使用电子卡尺在“分屏”上进行测量，以便直接比较沿血管相应水平的后续CT系列资料。主要观察指标为术后肾上和肾下主动脉直径的变化。
术后首次检查的平均（±标准差）时间为7.0±3.5个月，最后一次检查为44.4±21个月。在此时间段内，肾上直径的估计变化率为0.18 mm/年，95%置信区间（CI）为0.08至0.27。肾下直径的估计变化率为0.16（95%CI：0.05至0.27）。7例患者（13%）观察到临床上相关的直径增加≥3 mm。有证据表明，直径增加幅度较大与AAA直径较大相关（肾上和肾下直径的P值分别为0.003和<0.001），呈倒漏斗形（P值分别为0.002和<0.001），以及与腹股沟疝病史相关的边缘证据（P值分别为0.043和0.066）。
尽管有统计学意义的证据表明传统AAA修复术后肾上和肾下主动脉直径增加，但年平均增加幅度往往较小，仅一小部分病例观察到临床上相关的3 mm或更大的增加。
