Studies have shown that cerebrovascular disease has become the second leading disease in the population in terms of mortality, 80% of which are ischemic strokes, 2/3 of which are associated with carotid stenosis in patients. Surgical treatment of carotid stenosis began in the 1950s, and with the development of a number of new endoluminal techniques such as the cerebral protection device at the end of the last century, stenting became another option for surgical intervention of carotid stenosis. However, whether all patients with carotid stenosis require surgical intervention and if the appropriate modality for intervention is chosen has become a hot topic of discussion, which is briefly reviewed in this article.
1. Which patients do not require immediate surgery and can be treated medically?
All patients with carotid stenosis should be treated medically to prevent the development of cerebral infarction. Some studies suggest that all patients with symptomatic carotid stenosis with less than 50% stenosis should be treated with medication because the risk-benefit ratio of surgical treatment in this group of patients needs to be further improved. In contrast, if asymptomatic patients with less than 50% carotid stenosis and no other cardiovascular risk factors are present, the evidence for the need to initiate pharmacologic therapy is not yet strong. Aspirin antiplatelet therapy is effective in reducing the incidence of all-cause cardiovascular events without adding additional risk, while the evidence for statins as primary prevention is not yet strong.
It is currently believed that patients with symptomatic carotid stenosis <50% with stenosis that is contraindicated for surgery may receive drug therapy alone at approximately 50-69%. The main reasons why CAS treatment is recommended for post-operative restenosis after CEA include the increased chance of cranial nerve injury due to redissection of the scar site, which is, of course, not an absolute contraindication, as confirmed by a retrospective study of 249 patients with post-operative carotid restenosis A retrospective study confirmed that the secondary operative mortality and cerebral infarction rate was only 2.9% in 249 patients with postcarotid restenosis. In contrast, postoperative restenosis after CAS should be treated with CEA because such patients tend to have no surgical scars in the neck and the stenotic stent can be removed by standard endarterectomy, but the stent may interfere with the carotid artery blocking process during the procedure. One study found that the choice of procedure did not affect the prognosis during secondary intervention for postoperative restenosis, and its overall complication rate remained higher than that of phase I surgery, which also proves that a more conservative attitude should be adopted in the case of carotid restenosis.
In conclusion, surgical indications, techniques, and the search for long-term safety in the treatment of carotid artery stenosis have advanced considerably, and China should rely on a large amount of clinical experience to advance the development of this field.
Carotid Body Aneurysm
Carotid body aneurysm is an extra-adrenal parasympathetic ganglion aneurysm, mostly located in the posterior medial outer sheath of the carotid bifurcation, and is the most common parasympathetic ganglion aneurysm of the head and neck. Approximately 20% of carotid body aneurysms have a family history and are inherited in an autosomal dominant fashion. SDH (succinate dehydrogenase) mutations have been shown to be associated with the development of paragangliomas. 42.5% of patients with carotid body tumors were found to have SDH mutations, with SDHD and SDHB mutations in the SDH subunit being the predominant ones. It has been suggested that familial head and neck paragangliomas in Chinese may be associated with SDHD initiation codon missense mutations.
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