Bornstein N M, Norris J W
Department of Neurology, Ichilov Hospital, Tel Aviv University, Israel.
Cerebrovasc Brain Metab Rev. 1993 Winter;5(4):301-13.
About 4% of adults have asymptomatic neck bruits, and this frequency increases with age. Only a small number of these (about 25%), however, have asymptomatic carotid stenosis (ACS), and only 10% of these have stenoses > 75%. The vascular outcome for patients with ACS depends upon the severity of carotid stenosis, all outcomes worsening after 75-80% stenoses. For stenoses < 50%, annual stroke rate is about 1% and does not change in stenoses 50-75%, but over 75%, annual stroke rate increases to 3.3% per year. Ischaemic cardiac event rate is 2.7% annually for stenoses < 50%, 6.6% for those 50-75%, and 8.3% for stenoses > 75%. Annual vascular death rates also rise from 1.8%, 3.3% and 6.5% respectively. Stroke risk factors such as hypertension and smoking are important in early plaque formation, but when plaques become stenosing, local hemodynamic factors such as turbulence are the major factors in arterial remodelling. No medical or surgical therapy has yet been found effective, but current surgical randomized trials may reveal the answer in the near future.
约4%的成年人有无症状颈部杂音，且这一频率随年龄增长而增加。然而，其中只有一小部分人（约25%）有无症状性颈动脉狭窄（ACS），而这些人中只有10%的狭窄程度>75%。ACS患者的血管转归取决于颈动脉狭窄的严重程度，狭窄程度达到75% - 80%后，所有转归情况都会恶化。对于狭窄程度<50%的患者，年中风发生率约为1%，在狭窄程度为50% - 75%时不变，但超过75%时，年中风发生率会增至每年3.3%。对于狭窄程度<50%的患者，缺血性心脏事件发生率为每年2.7%，50% - 75%的患者为6.6%，>75%的患者为8.3%。年血管死亡率也分别从1.8%、3.3%升至6.5%。高血压和吸烟等中风危险因素在早期斑块形成中很重要，但当斑块导致狭窄时，局部血流动力学因素如湍流是动脉重塑的主要因素。目前尚未发现有效的药物或手术治疗方法，但当前的外科随机试验可能在不久的将来揭示答案。
