Faggioli Gianluca, Ferri Monica, Gargiulo Mauro, Freyrie Antonio, Fratesi Francesca, Manzoli Lamberto, Stella Andrea
Department of Vascular Surgery, University of Bologna, Bologna, Italy.
J Vasc Surg. 2007 Dec;46(6):1119-24. doi: 10.1016/j.jvs.2007.08.027.
Proximal and distal carotid tortuosity is considered of paramount importance in carotid artery stenting (CAS) procedures. Specifically, distal internal carotid coiling or kinking is thought to interfere with proper distal protection devices, thus contraindicating CAS. The type of the aortic arch is also considered a key factor in CAS success; however, no standardized method of evaluation of these indicators is available in the literature. We have evaluated the impact of arch angulation and proximal and distal tortuosity in a series of CAS procedures.
In patients undergoing CAS, arch angulation and tortuosity of both common and distal internal carotid arteries were evaluated prospectively by calculating the sum of all angles diverging from the ideal straight axis, considering a 90 degrees ideal angle for the origin from the arch (tortuosity index, TI). All procedures were through a transfemoral approach and with distal protection. Results were correlated with technical procedural success (residual stenosis <30%) and neurologic complication by Student t test. Multivariate logistic regression analysis was conducted to identify independent predictors of results.
In a group of 298 CAS procedures, the mean proximal TI was 111.9 degrees +/- 96.77 degrees and the mean distal TI was 123.4 degrees +/- 117.47 degrees . Technical success was obtained in 272 patients (91.2%). Causes for the 26 technical failures were incapacity to obtain stable proximal access in 25 (96.1%), and uncrossable stenosis in one (3.9%). Neurologic protection was achieved with distal filters in all cases. Neurologic complications occurred in 23 patients (7.7%), consisting of 16 transient ischemic attacks and seven minor strokes. The proximal TI was significantly greater in the 26 cases of technical failure (158.4 degrees +/- 102.2 degrees vs 107.6 degrees +/- 95.3 degrees , P = .01). The distal TI was not different in the two groups (89 degrees +/- 99.1 degrees vs 126.5 degrees +/- 118.6 degrees , P = .11). Similarly, the proximal TI was significantly greater in neurologic complications (162.8 degrees +/- 111.8 degrees vs 107.6 degrees +/- 18.2 degrees , P = .03); the distal TI was not different in the two groups (112.6 degrees +/- 110.1 degrees vs 124.3 degrees +/- 96.1 degrees , P = .5) By logistic regression analysis, a proximal TI >150 was an independent predictor of both neurologic complications and technical failure. Age was also independently associated with technical failure. Appropriate distal filter placement was possible in all cases with a crossable stenosis, irrespective of the internal carotid TI.
The proximal TI is significantly associated with both technical success and neurologic complications after CAS, whereas the distal TI did not influence either outcome. The presence of distal kinking or coiling should not be considered a contraindication to CAS.
颈总动脉近段和远段迂曲在颈动脉支架置入术（CAS）中被认为至关重要。具体而言，颈内动脉远段盘绕或扭结被认为会干扰合适的远端保护装置，因此成为CAS的禁忌证。主动脉弓类型也被视为CAS成功的关键因素；然而，文献中尚无评估这些指标的标准化方法。我们在一系列CAS手术中评估了主动脉弓角度以及近段和远段迂曲的影响。
在接受CAS的患者中，通过计算偏离理想直线轴的所有角度之和来前瞻性评估主动脉弓角度以及颈总动脉和颈内动脉远段的迂曲情况，将主动脉弓起始处的理想角度设定为90度（迂曲指数，TI）。所有手术均经股动脉途径并采用远端保护。通过Student t检验将结果与手术技术成功（残余狭窄<30%）和神经并发症相关联。进行多因素逻辑回归分析以确定结果的独立预测因素。
在一组298例CAS手术中，近端TI的平均值为111.9度±96.77度，远端TI的平均值为123.4度±117.47度。272例患者（91.2%）获得技术成功。26例技术失败的原因中，25例（96.1%）是无法获得稳定的近端通路，1例（3.9%）是狭窄无法通过。所有病例均使用远端滤器实现了神经保护。23例患者（7.7%）发生神经并发症，包括16例短暂性脑缺血发作和7例轻度卒中。26例技术失败病例的近端TI显著更高（158.4度±102.2度对107.6度±95.3度，P = 0.01）。两组的远端TI无差异（89度±99.1度对126.5度±118.6度，P = 0.11）。同样，神经并发症患者的近端TI显著更高（162.8度±111.8度对107.6度±18.2度，P = 0.03）；两组的远端TI无差异（112.6度±110.1度对124.3度±96.1度，P = 0.5）。通过逻辑回归分析，近端TI>150是神经并发症和技术失败的独立预测因素。年龄也与技术失败独立相关。在所有狭窄可通过的病例中，无论颈内动脉TI如何，均有可能成功放置合适的远端滤器。
近端TI与CAS术后的技术成功和神经并发症均显著相关，而远端TI对两种结果均无影响。颈内动脉远段扭结或盘绕不应被视为CAS的禁忌证。
