Carotid endarterectomy (CEA) is the “gold standard” for the treatment of carotid stenosis and stroke prevention. In the process of promoting CEA, I found that many colleagues can basically master the surgical skills, but there is still a gap between the conceptual understanding, surgical selection, technical concept and complication prevention and control and the international advanced level. In practice, many colleagues still struggle with the following questions: Does CEA cut the plaque or the endothelium? How to excise? What is the site of resection? To what extent? Do we need to do additional vascular trimming and anastomosis? In this article, we present an overview of four controversies in the “real world” of CEA – conceptual doubts, procedural problems, conceptual differences, and technical confusion – and share with you our thoughts on the latest developments in the field. We will also share with you the latest developments in this field. Carotid endarterectomy (CEA), the “gold standard” for the treatment of carotid stenosis and stroke prevention, has been developed in the Western world for more than 60 years and has become relatively mature [1-2]. The technology was introduced in China in the 1990s [3], but was not successfully promoted at the beginning for various reasons. Wang Longde pointed out in the 2016 China Stroke Conference that the Chinese government launched the “Stroke Screening and Prevention Project”, and that CEA has been rapidly promoted and developed throughout the country due to the active promotion by multidisciplinary colleagues in vascular surgery, neurosurgery, and cardiac surgery. [4] The author has studied CEA as a practicing physician in the Department of Vascular Surgery of the University of Erlangen-Nuremberg Medical School in Germany, the largest vascular surgery center in Europe, for nearly 3 years. He has performed nearly 4000 surgeries in more than 20 provinces and 70 units nationwide [8], and his center has been approved as one of the first national training bases for CEA technology and expert technical service bases for carotid-related stroke screening and prevention. In the promotion of CEA, I found that although many colleagues can basically master the surgical skills, there is still a gap between the conceptual understanding, surgical selection, technical concept and complication prevention and control, and in practice, they still struggle with the question “Is CEA to cut the plaque or the endothelium? How to excise? Where to remove? To what extent? Is it necessary to do additional vascular cutting and anastomosis formation?” The paper addresses the issue of CEA in the “real world”. In this paper, we summarize several controversies of CEA in the “real world” and present our personal thoughts for discussion. 1.Doubtful concept of resection of “plaque” or “endarterectomy”? The term “Carotid endarterectomy” was introduced into China and was directly translated as “carotid endarterectomy”, which literally means “surgery to remove the carotid artery intima “It is literally a procedure to remove the endothelium of the carotid artery. This brings questions to many patients and even medical workers: the “culprit” of carotid artery sclerosis and stenosis is the “plaque”, why must the “intima” be removed? More seriously, some beginners of CEA cannot understand the nature of CEA in practice and have difficulty in finding the correct tissue level when removing the plaque. The author believes that the inaccuracy of the concept and content of the Chinese name of the procedure is one of the major reasons that limit the acceptance and promotion of the technique. The purpose of CEA is to remove or exfoliate the localized atherosclerotic plaque that causes narrowing or occlusion of the carotid lumen, i.e., remove the plaque to avoid plaque dislodgement and embolism leading to ischemic stroke, and to expand the carotid lumen to improve the blood supply to the brain. The plaque mainly includes the intima and fibrous cap, the lipid pool and plaque, and part of the intima. Therefore, in order to remove the carotid atherosclerotic plaque, the carotid intima corresponding to the diseased plaque cannot be preserved and repaired, and is removed together due to the “bystander effect” (Figure 1). Based on the above connotation of the procedure, I believe that the name should be clarified as “carotid endarterectomy” [9], although only the word “plaque” is added, it is more suitable for the purpose of the procedure and the actual operation, which is convenient for doctors and patients to accurately understand the connotation of CEA and facilitate the promotion It is convenient for doctors and patients to accurately understand the meaning of CEA and facilitate its promotion. 2. How to choose the best procedure? There are four main types of CEA: conventional, patching, exenteration and carotid fractional resection + intervascular placement (Figure 2). The conventional CEA removes plaque through a longitudinal carotid incision and sutures it in situ continuously, which makes it difficult to avoid lumen loss due to direct suturing over the longitudinal incision of the original artery. Carotid fractional resection + interposition CEA is only indicated in about 5% of exceptional cases [8]. Patch CEA is the addition of vascular patch shaping to the traditional CEA procedure, which has the advantage of enlarging the vascular anastomosis and effectively preventing postoperative anastomotic stenosis, but this procedure increases the difficulty of the procedure and the risk of postoperative graft infection, bleeding, patch aneurysm, and distal artery collapse. External CEA is a further improvement of traditional CEA, in which the internal carotid artery is completely cut off obliquely from the common carotid artery, and the plaque stripping of the internal carotid artery is performed first, followed by the plaque stripping of the common carotid artery and external carotid artery, and the anastomosis is shaped and the internal and common carotid arteries are anastomosed in situ. The disadvantage is that the technical operation is relatively demanding. At present, there are two major shortcomings in the selection of CEA in China: first, the traditional CEA, which has been proven to be outdated by evidence-based medicine, is still used in most centers [11-12]; second, many centers are unable to select the best procedure for each patient individually because they cannot master all the techniques of the procedure. For the former, several clinical studies have confirmed that the incidence of restenosis after conventional CEA is significantly higher than that of exenteration and patching, and its routine use has been discouraged more than 10 years ago in foreign countries [10], and our physicians should also update their concepts and switch to patching or exenteration CEA as soon as possible. Therefore, the author combined relevant evidence-based medical evidence with the experience of nearly 4,000 cases of CEA in the “real world” and proposed the first “individualized selection scheme of CEA procedures” in China (Table 1) [13]. For example, for an 84-year-old female patient with severe carotid stenosis combined with torsion who was taking dual antiplatelet drugs after previous coronary stenting, external CEA should be the best choice. 3.Differences in philosophy: pursuing “refined” or “flowing”? At present, there are different concepts and understanding of the specific operation concept of CEA in domestic academic circles. In recent years, the concept of “micro-CEA” has been proposed, which advocates the completion of carotid artery exposure, endothelial plaque removal and vascular anastomosis under the microscope; especially in the treatment of endothelial plaque, through the microscopic In particular, in the treatment of intimal plaque, the plaque is removed under the microscope by careful observation, and the plaque is removed in a thorough manner without residue, and the peeled surface is repeatedly wiped to make it as smooth as possible, so as to minimize the residue of plaque debris from causing stroke. The vascular surgeon, on the other hand, draws on the technical concept of cardiac surgery and advocates a “flowing” operation, using sharp dissection under direct vision or low magnification to operate on the vessel; the main focus is on the removal of intimal plaque and floating debris; the suture spacing is controlled, not too dense or too loose, and continuous suturing is performed at the appropriate spacing. In the author’s opinion, the operation of CEA should follow the principles of “sharp dissection”, “proximity” and “moderation”. “Sharp dissection” refers to the use of vascular scissors and non-invasive forceps instead of electric knife and hemostatic forceps to perform sharp dissection of vessels. The “proximity principle” refers to the use of dissection as close to the vessel as possible to reduce the damage to the surrounding tissues and nerves. Because there are trophoblastic vessels and nerves on the outer membrane of the artery, the smaller the damage, the better the postoperative trophoblastic condition of the carotid artery and the lower the risk of restenosis. For this reason, the author generally chooses to perform sharp dissection under low magnification to minimize the damage to the vessels and surrounding tissues. “The principle of “moderation” refers to the fact that the intimal treatment is not overly emphasized, and the sutures should not be too tight or too tight. Therefore, no matter how clean and smooth the intraoperative debridement is, the endothelial surface will be covered by the relevant tissue cells after the procedure; in addition, repeated wiping is a kind of damage to the vessel, which will increase the risk of postoperative thrombosis and aggravate the degree of endothelial hyperplasia [14]. A small amount of debris and air residue is also unavoidable and can be adequately drained by proper cleaning, return bleeding flushing, and the correct anastomosis and block release sequence to avoid embolic stroke, which has also been well documented in a large clinical sample [8]. Fine sutures ensure less blood leakage, but the all-over damage to the vessel wall by fine sutures induces excessive endothelial hyperplasia, and the more non-absorbable sutures and the denser the foreign body irritation triggers the heavier the endothelial hyperplasia (Figure 3) [15]. The author believes that vascular suturing should find the best balance between ensuring no blood leakage and reducing foreign body irritation by choosing the right size suture and the best stitch distance. Usually 6-0 Polypropylene sutures are chosen for CEA; the stitch spacing is usually 2-3 mm for inter-vessel sutures and 1-2 mm for artificial vessels to ensure no blood leakage and to reduce suture use and shorten operative time. 4.Technical confusion Challenges and improvement of the existing external CEA External CEA has become a mainstream procedure in foreign countries because of the advantages of simple procedure, no risk of graft infection, restoration of the original anatomy of the carotid artery, and low risk of postoperative restenosis. However, domestic scholars still have the following doubts because of the concept and understanding: the choice of the boundary between plaque intima and normal intima dissection, the difficulty to remove the plaque of proximal bifurcation, common carotid artery and external carotid artery, and the postoperative anastomosis narrowing. The difficulty in choosing the boundary between plaque intima and normal intima dissection occurs mostly when the distal carotid artery is externally debrided to remove the intimal plaque, and the distal normal intima may become locally edematous and be mistaken as abnormal “plaque tissue” and be debrided. Dissection. In order to avoid this situation, the distal end should be dissected after the plaque is confirmed to be free of plaque during external reversal debridement, and complete debridement is confirmed if the end of the debrided intimal plaque shows the typical “cicada wing sign” (Figure 4). To address the problems of difficult resection of proximal bifurcation, common carotid artery, and external carotid artery plaque and postoperative anastomotic narrowing, our center has improved the existing external CEA [8,16] and proposed the concept of “modified external CEA” (registration number ChiCTR-INR-17010331) for the first time, mainly By improving the direction and angle of the internal carotid artery incision and increasing the anastomosis, a series of operations can fully reveal the plaque of the bifurcation, common carotid artery, external carotid artery and even superior thyroid artery, and fully enlarge the lumen of the anastomosis, and more importantly, reconstruct the original anatomical structure of the “dilated internal carotid artery” and restore the normal hemodynamics. The procedure is as follows The first step is as follows: in the first step, the plaque is resected, and the plaque is dissected obliquely along the beginning of the enlarged internal carotid artery, and the epicardium is fully turned out to expose the diseased intima and plaque to the relatively normal intimal migration of the internal carotid artery, at this time, the diseased part of the intimal plaque can be dislodged by itself, and there is no need to fix the intima. In cases where the endothelial section is really obvious and the possibility of formation of entrapment is expected to be high, endothelial fixation can be performed. In the second step, “angioplasty”, the internal carotid artery and common carotid artery are appropriately clipped to fully enlarge the anastomotic area. In the third step, “hemodynamic restoration”, the anastomosis is sutured continuously to reconstruct the anatomical structure of the carotid bifurcation, and the expansion of the internal carotid artery can be observed to restore the carotid bifurcation hemodynamics (Figure 5). The above operation can preemptively leave enough space for the anastomotic intimal hyperplasia, effectively avoiding postoperative intimal hyperplasia restenosis and achieving the effect of restenosis prevention. Our center has controlled the mid- and long-term restenosis rate of ectopic CEA to 0.5%, which is much lower than the average postoperative restenosis rate of 2%-5% for CEA required by the latest US guidelines [17]. It has been less than 10 years since CEA, the “gold standard” for treatment of carotid artery stenosis and stroke prevention, has been rapidly promoted and popularized in China, and with the continuous efforts of our multidisciplinary colleagues in vascular surgery, neurosurgery, and cardiac surgery, it is being further integrated with the Chinese context. CEA is a seemingly simple, high-risk procedure that requires formal theoretical training and clinical practice.