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Primary Carotid Stenting

Published online by Cambridge University Press:  04 November 2014

David Pelz*
Affiliation:
Departments of Medical Imaging, and Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada.
Stephen Lownie
Affiliation:
Departments of Medical Imaging, and Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada.
*
Correspondence to: David Pelz, University Hospital - Medical Imaging, 339 Windermere Rd., London, Ontario, N6A5A5 Canada. E-mail: pelz@uwo.ca
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Abstract

Type
Neuroimaging Highlight
Copyright
Copyright © The Canadian Journal of Neurological Sciences Inc. 2014 

A 66-year-old male presented with right hemispheric transient ischemic attacks. Computed tomography angiography (CTA) demonstrated a very severe atherosclerotic stenosis of the proximal right internal carotid artery, >95% by NASCET criteria. Carotid stenting was performed using a self-expanding stent (SES) alone, without balloon angioplasty or embolic protection. An immediate anteroposterior (AP) x-ray of the neck (Figure 1) shows the stent in place. A carotid Doppler done the same day demonstrated a peak systolic velocity (PSV) of 142 cm/sec and an internal carotid to common carotid artery (ICA/CCA) velocity ratio of 1.8, corresponding to a stenosis of approximately 50%. Six weeks later, the stent had gently expanded by itself (Figure 2). The Doppler showed a PSV of 91 cm/sec and an ICA/CCA ratio of 0.87, indicating no residual stenosis. The patient remains asymptomatic.

Figure 1 AP neck X-ray immediately post-stenting.

Figure 2 AP neck X-ray 6 weeks post- stenting.

In the major randomized controlled trials (RCTs) comparing carotid endarterectomy to carotid angioplasty and stenting (CAS), the endovascular procedure is performed using pre-and post-stenting balloon angioplasty and embolic protection devices (EPDs).Reference Brott, Hobson and Howard 1 , 2 Balloon angioplasty is one of the most embologenic stages of CAS, and may result in significant hemodynamic instability.Reference Almekhlafi, Demchuk and Mishra 3 , Reference Qazi, Obeid, Enwerem and Schneider 4 Embolic protection devices are expensive, do not catch all emboli and are themselves associated with unique complications.Reference Tallarita, Rabinstein and Cloft 5 In selected patients, particularly those with little calcification of carotid plaque on CTA source images,Reference Pelz, Lownie, Lee and Boulton 6 use of balloon angioplasty and EPDs can be avoided. A SES may be all that is required for a successful outcome.Reference Men, Lownie and Pelz 7 , Reference Bussiere, Pelz and Kalapos 8 This less invasive approach, termed primary carotid stenting (Figure 3) has not yet undergone RCT validation but it is faster, cheaper and potentially safer than standard techniques.Reference Bussiere, Lownie, Lee, Gulka, Leung and Pelz 9 , Reference Lopez-Ojeda, Munoz, Solo, Lownie and Pelz 10

Figure 3 Primary Carotid Stenting. A self-expanding stent alone is used to gently open the internal carotid artery, usually over 4-6 weeks No balloon angioplasty or embolic protection device is used.

As Occam’s Razor tells us: “It is vain to do with more what can be done with less.”

Acknowledgements

The authors thank Ms. Cathy Carlisle for secretarial assistance.

References

1. Brott, TG, Hobson, RW 2nd, Howard, G, et al. Stenting versus endarterectomy for treatment of carotid-artery stenosis. N Engl J Med. 2010;363:11-23.Google Scholar
2. International Carotid Stenting Study investigators. Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis International Carotid Stenting Study: an interim analysis of a randomized controlled trial. Lancet. 2010;376:985-997.Google Scholar
3. Almekhlafi, MA, Demchuk, AM, Mishra, S, et al. Malignant emboli on transcranial Doppler during carotid stenting predict postprocedure diffusion-weighted imaging lesions. Stroke. 2013;44:1317-1322.CrossRefGoogle ScholarPubMed
4. Qazi, U, Obeid, TE, Enwerem, N, Schneider, E, et al. The effect of ballooning following carotid stent deployment on hemodynamic stability. J Vasc Surg. 2014;59:756-760.Google Scholar
5. Tallarita, T, Rabinstein, AA, Cloft, H, et al. Are distal protection devices ‘protective’ during carotid angioplasty and stenting? Stroke. 2011;42:1962-1966.CrossRefGoogle ScholarPubMed
6. Pelz, DM, Lownie, SP, Lee, DH, Boulton, MR. CTA Plaque Morphology (The PLAC Scale) Predicts Long-Term Anatomic Success of Primary Carotid Stenting. J Neurosurg. 2014, In press.Google Scholar
7. Men, S, Lownie, SP, Pelz, DM. Carotid stenting without angioplasty. Can J Neurol Sci. 2002;29:175-179.Google Scholar
8. Bussiere, M, Pelz, DM, Kalapos, P, et al. Results using a self-expanding stent alone in the treatment of severe symptomatic carotid bifurcation stenosis. J Neurosurg. 2008;109:454-460.CrossRefGoogle ScholarPubMed
9. Bussiere, M, Lownie, SP, Lee, D, Gulka, I, Leung, A, Pelz, DM. Hemodynamic instability during carotid artery stenting: the relative contribution of stent deployment versus balloon dilation. J Neurosurg. 2009;110:905-912.CrossRefGoogle ScholarPubMed
10. Lopez-Ojeda, P, Munoz, C, Solo, K, Lownie, S, Pelz, D. Safety evaluation of primary carotid stenting: Embolic detection on intraprocedural transcranial Doppler and correlation with diffusion weighted imaging lesions on postprocedure magnetic resonance imaging. Abstr. 0-891. American Society of Neuroradiology 52nd Annual Meeting, Montreal, Quebec May 2014.Google Scholar
Figure 0

Figure 1 AP neck X-ray immediately post-stenting.

Figure 1

Figure 2 AP neck X-ray 6 weeks post- stenting.

Figure 2

Figure 3 Primary Carotid Stenting. A self-expanding stent alone is used to gently open the internal carotid artery, usually over 4-6 weeks No balloon angioplasty or embolic protection device is used.