Invited commentary

Abstract

The authors have presented their results with a hybrid system to treat patients at “high” risk for carotid endarterectomy (CEA) with excellent results. However, comparable outcomes have been reported in similar high-risk patients undergoing CEA or redo CEA, suggesting nonsuperiority of one technique over the other. Among the symptomatic patients in this study, we do not know how many had experienced recent symptoms (≤7 to 14 days) of carotid artery stenting (CAS) as opposed to those with symptoms up to 6 months before CAS. Rantner et al1Rantner B. Goebel G. Bonati L.H. Ringlab P.A. Mas J.L. Fradrich G. The risk of carotid artery stenting compared with CEA is greatest in patients treated within 7 days of symptoms.J Vasc Surg. 2013; 57: 619-626Abstract Full Text Full Text PDF PubMed Scopus (103) Google Scholar reported that the risk of CAS is greatest ≤7 days of a neurologic event. These patients would be expected to have a higher stroke rate than those with more remote symptoms. Advocates of the transcervical approach argue that avoiding catheter manipulation in the aortic arch is important in decreasing the risks of periprocedural strokes from macroemboli. Microembolic infarcts are seen after CAS with the transfemoral and transcervical approaches. Rapp et al2Rapp J.H. Wakil L. Sawhney R. Pan X.M. Yenari M.A. Glastonbury C. et al.Subclinical embolization after carotid artery stenting: new lesions on diffusion-weighted magnetic resonance imaging occur postprocedure.J Vasc Surg. 2007; 45: 867-874Abstract Full Text Full Text PDF PubMed Scopus (95) Google Scholar demonstrated that most microembolic infarcts seen on magnetic resonance images (MRIs) are not seen on the initial post-CAS MRI but appear on the 48-hour MRI, suggesting that the microemboli arise from the stent itself. Unfortunately, the authors did not perform pre-CAS and post-CAS MRIs on their patients. Although most microemboli produce no symptoms, microembolic brain infarcts may have subsequent clinical significance. In a case-control study, Purandare et al3Purandare N. Burns A. Daily K.J. Hardicre J. Morrie J. MacFarlane G. et al.Cerebral emboli is a potential cause of Alzheimer's disease and vascular dementia: case-control study.BMJ. 2006; 332: 1119-1125Crossref PubMed Scopus (111) Google Scholar demonstrated a significantly higher incidence of cerebral emboli in patients with Alzheimer disease and vascular dementia compared with controls. Only long-term follow-up will tell us the possible significance of the microembolic brain infarcts frequently observed after CAS. Finally, there are the arterial complications associated with this device. There were eight carotid artery dissections. There was also one case of a severe common carotid artery stenosis caused by a pursestring suture. I suspect that on long-term follow-up, Duplex scans would demonstrate a significant number of common carotid artery stenoses at the site of the pursestring because the proximal common carotid artery is rarely a normal vessel. Only long-term follow-up and more experience will tell us if this device and technique is indeed a better “mousetrap.” I hope that the authors will provide such follow-up in subsequent reports. Results of the ROADSTER multicenter trial of transcarotid stenting with dynamic flow reversalJournal of Vascular SurgeryVol. 62Issue 5PreviewThis report presents the 30-day results of the Safety and Efficacy Study for Reverse Flow Used During Carotid Artery Stenting Procedure (ROADSTER) multicenter trial and evaluates the safety and efficacy of ENROUTE Transcarotid NPS (Silk Road Medical Inc, Sunnyvale, Calif), a novel transcarotid neuroprotection system that provides direct surgical common carotid access and cerebral embolic protection via high-rate flow reversal during carotid artery stenting (CAS). Full-Text PDF Open Archive