The Aortic Arch: Markers, Imaging, and Procedure Planning for Carotid Intervention
- Volume 6 - Issue 1 - Jan/Feb 2009
- Posted on: 1/14/09
- 1 Comments
- 21139 reads
Christos D. Liapis, MD, Efthimios D. Avgerinos, MD, Achilles Chatziioannou, MD
From the University Hospital Attikon, Department of Vascular Surgery, Athens, Greece.
Correspondence: Christos D. Liapis, MD, University Hospital Attikon, Department of Vascular Surgery, 1 Rimini Street, Chaidari, Athens 12462, Greece. E-mail: email@example.com.
Manuscript submitted September 15, 2008, provisional acceptance given, November 5, 2008, accepted November 13, 2008.
Disclosure: The authors report no financial relationships or conflicts of interest regarding the content herein.
Among the several anatomic risk predictors for carotid stenting (e.g., extensive plaque ulceration, aneurysmal internal carotid artery, lesion length > 3 cm) (CAS), the aortic arch emerges as a key anatomic feature. Gaining access to the carotid lesion necessitates traversing the aortic arch and the proximal carotid arteries. Most technical failures in carotid stenting are related to a complex aortic arch whose role in CAS outcome rises as a crucial element of patient selection. The arch markers for selecting patients for carotid interventions include arch elongation, arch vessel origin configuration, arch calcification, and arch vessel origin stenosis. These markers get significantly unfavorable with increasing age. Cautious pre-interventional imaging is paramount in indentifying potential arch complexity and direct the interventional strategy. CAS practitioners would be advised to start their experience in younger patients with predominantly noncalcified type 1 arches.
Despite increasing experience in carotid angioplasty and stenting (CAS), optimal patient and anatomy selection remain the most important considerations for a successful outcome. Technical limitations and complications still exist, denoting that several issues still remain to be resolved.
Contrary to carotid endarterectomy (CEA) being non-favorable for patients with severe medical comorbidities, CAS is usually not indicated on the basis of anatomical limitations, not only of the carotids, but of the entire pathway, from the puncture site to the cerebral arteries.1 Among the several anatomic risk predictors (e.g., extensive plaque ulceration, aneurysmal internal carotid artery, lesion length > 3 cm), the aortic arch emerges as a key anatomic feature for CAS success (or failure).1,2
Regardless of the complexity of the internal carotid lesion or the degree of stenosis, accessing those lesions with the appropriate filter and stent is usually technically feasible. The arch, however, is a different challenge. Initially, its role had been underestimated and was not considered a major procedural limitation. Recently, the aortic arch has become a crucial element in patient selection for CAS, with arch markers being used to guide the operator for case selection and pre-interventional planning.2,3
The arch markers for selecting patients for carotid interventions include arch elongation, arch vessel origin configuration, arch calcification, and arch vessel origin stenosis. This review focuses on aortic arch features, anatomy assessment, patient selection, and planning and execution without compromising patient safety.
Arch elongation and arch vessel configuration. It is important to recognize the type of aortic arch and the configuration of the great vessels in each patient, since these anatomic features influence procedure complexity.
The aortic arch elongation classification was conceived to picture an increasing procedural difficulty in vessel cannulation (Figure 1), which was also helpful in designing catheter configurations, allowing easier access to the great vessels off the arch. There are three types of aortic arches based on the relationship of the innominate artery to the aortic arch or on the parallel planes perpendicular to the greater (outer) curvature and lesser (inner) curvature of the arch.4–6 Some authors have also suggested a type IV arch.2
Alternatively, arch complexity can be assessed by drawing a line horizontally across the upper inner aspect of the arch. When the origin of the target artery is above the horizontal line and to the patients’ right, catheterization presents a moderate degree of challenge. The closer the arch branch origin is to the horizontal line, the more challenging it becomes.7
• Type I arch. The arch vessels arise from the outer curvature of the arch in the same horizontal plane (no angulation). The vertical distance from the origin of the innominate artery to the top of the arch is < 1 diameter of the left common carotid artery (CCA) (Figure 1a).
• Type II arch. The arch vessels arise between the parallel planes delineated by the outer and inner curves of the arch (moderate angulation). The vertical distance from the origin of the innominate artery to the top of the arch is between 1 and 2 left CCA diameters (Figure 1b).
• Type III arch. The arch vessels arise proximal or caudal to the lesser curvature of the arch or off the ascending aorta (severe angulation). The vertical distance from the origin of the innominate artery to the top of the arch is > 2 left CCA diameters (Figure 1c).
• Type IV arch. The arch vessels arise with severe angulation, accompanied by increased length and transverse diameters of the arch. This arch type is associated with redundancy of the CCA. It is more frequently noted on the right, where tortuosity and the redundant loop exist in the proximal segment of the CCA.
1. Schneider PA, Kasirajan K. Difficult anatomy: What characteristics are critical to good outcomes of either CEA or CAS? Semin Vasc Surg 2007;20:216–225.
2. Wholey MH. Anatomical and technical considerations of CAS. Endovascular Today 2006;8:60–64.
3. Liapis CD, Avgerinos ED, Chatziioannou A. Arch markers for selecting patients for carotid interventions. In Greenhalgh RM (ed): Vascular and Endovascular Consensus Update. London: BIBA Publishing, 2008.
4. Lin SC, Trocciola SM, Rhee J, et al. Analysis of anatomic factors and age in patients undergoing carotid angioplasty and stenting. Ann Vasc Surg 2005;19:798–804.
5. Lam RC, Lin SC, DeRubertis B, et al. The impact of increasing age on anatomic factors affecting carotid angioplasty and stenting. J Vasc Surg 2007;45:875–880.
6. Madhwal S, Rajagopal V, Bhatt DL, et al. Predictors of difficult carotid stenting as determined by aortic arch angiography. J Invasive Cardiol 2008;20:200–204.
7. Bohannon WT, Schneider PA, Silva MB. Aortic arch classification into segments facilitates carotid stenting. In Schneider PA, Bohannon WT, Silva MB (eds): Carotid Interventions. New York: Marcel Dekker, 2004:pp 15–22.
8. Schneider P. Advanced cerebrovascular arteriography: Applications in carotid stenting. In Schneider P, Bohannon W, Silva M (eds). Carotid Interventions. New York: Marcel Dekker, 2004:pp 69–91.
9. Ackerstaff RG, Suttorp MJ, van den Berg JC, et al. Prediction of early cerebral outcome by transcranial Doppler monitoring in carotid bifurcation angioplasty and stenting. J Vasc Surg 2005;41:618–624.
10. Crawley F, Stygall J, Lunn S, et al. Comparison of microembolism detected by transcranial Doppler and neuropsychological sequelae of carotid surgery and percutaneous transluminal. Stroke 2000;31:1329–1334.
11. Amarenco P, Cohen A, Tzourio C, et al. Atherosclerotic disease of the aortic arch and the risk of ischemic stroke. N Engl J Med 1994;331:1474–1479.
12. Davila-Roman VG, Barzilai B, Wareing TH, et al. Atherosclerosis of the ascending aorta. Prevalence and role as an independent predictor of cerebrovascular events in cardiac patients. Stroke 1994;25:2010–2016.
13. John R, Choudhri AF, Weinberg AD, et al. Multicenter review of preoperative risk factors for stroke after coronary artery bypass grafting. Ann Thorac Surg 2000;69:30–36.
14. Tuman KJ, McCarthy RJ, Najafi H, et al. Differential effects of advanced age on neurologic and cardiac risks of coronary artery operations. J Thorac Cardiovasc Surg 1992;104:1510–1517.
15. Salomon NW, Page US, Bigelow JC, et al. Coronary artery bypass grafting in elderly patients. Comparative results in a consecutive series of 469 patients older than 75 years. J Thorac Cardiovasc Surg 1991;101:209–218.
16. Hobson RW 2nd, Howard VJ, Roubin GS, et al. CREST investigators. Carotid artery stenting is associated with increased complications in octogenarians: 30-day stroke and death rates in the CREST lead-in phase. J Vasc Surg 2004;40:1106–1111.
17. Kastrup A, Schulz JB, Raygrotzki S, et al. Comparison of angioplasty and stenting with cerebral protection versus endarterectomy for treatment of internal carotid artery stenosis in elderly patients. J Vasc Surg 2004;40:945–951.
18. Criado F. Mastering carotid intervention. Endovascular Today 2003;9:65–68.
19. Groschel K, Pilgram SM, Ernemann U, et al. Aortic calcification on plain chest radiography predicts embolic complications during carotid artery stenting. Eur J Radiol 2008;15:730–736.
20. Balzer JO. How to introduce carotid angioplasty without compromising patient safety. Eur J Vasc Endovasc Surg 2008;36:138–144.
21. Schneider PA. Selective catheterization of the brachiocephalic arteries. In Schneider PA (ed): Endovascular Skills (2nd ed). New York: Marcel Dekker, 2003:pp 90–99.
22. Shaw JA, Gravereaux EC, Eisenhauer AC. Carotid stenting in the bovine arch. Catheter Cardiovasc Interv 2003;60:566–569.
23. Kastrup A, Gröschel K, Schnaudigel S, et al. Target lesion ulceration and arch calcification are associated with increased incidence of carotid stenting-associated ischemic lesions in octogenarians. J Vasc Surg 2008;47:88–95.
24. Setacci C, Donato G, Chisci E, et al. Is carotid artery stenting in octogenarians really dangerous? J Endovasc Ther 2006;13:302–309.
25. Faggioly G, et al. Measurement and impact of proximal and distal tortuosity in carotid stenting procedures J Vasc Surg 2007;46:1119–1124.
26. Faggioli GL, Ferri M, Freyrie A, et al. Aortic arch anomalies are associated with increased risk of neurological events in carotid stent procedures. Eur J Vasc Endovasc Surg 2007;33:436–441.
27. SAPPHIRE Investigators (Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy). Protected carotid-artery stenting versus endarterectomy in high-risk patients. N Engl J Med 2004;351:1493–1501.
28. Mas JL, Chatellier G, Beyssen B, et al. EVA-3S Investigators. Endarterectomy versus stenting in patients with symptomatic severe carotid stenosis. N Engl J Med 2006;355:1660–1671.
29. SPACE Collaborative Group, Ringleb PA, Allenberg J, et al. 30 day results from the SPACE trial of stent-protected angioplasty versus carotid endarterectomy in symptomatic patients: A randomized non-inferiority trial. Lancet 2006;368:1239–1247.
30. Gray WA, Hopkins LN, Yadav S, et al. Protected carotid stenting in high-surgical-risk patients: The ARCHeR results. J Vasc Surg 2006;44:258–269.
31. Gray WA, Yadav JS, Verta P, et al. The CAPTURE Registry: Predictors of outcomes in Carotid Artery Stenting With Embolic Protection for High Surgical Risk Patients in the Early Post-Approval Setting. Catheter Cardiovasc Interv 2007;70:1025–1033.
32. Iyer SS, White CJ, Hopkins LN, et al. Carotid artery revascularization in high-surgical-risk patients using the carotid WALLSTENT and FilterWire EX/EZ. J Am Coll Cardiol 2008;51:427–434.
33. ACCF/SCAI/SVMB/SIR/ASITN 2007 Clinical Expert Consensus Document on Carotid Stenting. J Am Coll Cardiol 2007;49:126–170.
34. Feldtman RW, Buckley CJ, Bohannon WT. How I do it: Cervical access for carotid artery stenting. Am J Surg 2006;192:779–781.
35. Laszlo P, Cagiannos C, Ruzsa Z, et al. Report on initial experience with transradial access for carotid artery stenting. J Vasc Surg 2007;45:1136–1141.
36. Liapis CD, Michailidis D, Sivenius J, et al. ESVS guidelines. Invasive treatment for carotid stenosis: Indications-techniques. Eur J Vasc Endovasc Surg In press.