Olin J W, Fonseca C, Childs M B, Piedmonte M R, Hertzer N R, Young J R
Department of Vascular Medicine, Cleveland Clinic Foundation, OH, USA.
Vasc Med. 1998;3(2):101-8. doi: 10.1177/1358836X9800300203.
The purpose of this study was to determine the rate of progression of the degree of carotid stenosis and to determine the risk of continued observation in a group of asymptomatic patients with moderate stenosis of at least one internal carotid artery. Between 1989 and 1994, 2130 patients were found to have 60-79% stenosis of at least one internal carotid artery following a duplex ultrasound examination in the authors' vascular laboratory. Of these, 465 patients (255 men, 210 women) were asymptomatic and had more than one ultrasound examination, and they form the basis of this retrospective review. The mean +/- SD age was 68.8 +/- 9.0 years. The mean +/- SD number of ultrasound examinations was 3.1 +/- 1.4 (range 2-11). The mean +/- SD follow-up was 24.4 +/- 17.6 months (range 2-79 months). Over the period of follow-up 72 patients (15.5%) progressed to 80-99% stenosis (n = 71) or to occlusion (n = 1). The estimated percentage of patients who progressed by life table methods were 5 +/- 1% at 1 year, 11 +/- 2% at 2 years and 20 +/- 3% at 3 years. There was no statistically significant difference in the rate of progression in men compared with women. Twenty-one patients had a late ipsilateral TIA or stroke. Five out of 72 patients (6.9%) who progressed had a late ipsilateral TIA compared with nine out of 393 patients (2.3%) who did not progress (estimated risk ratio 16.1, P = 0.0001). Four out of 72 patients (5.6%) who progressed had a late ipsilateral stroke compared with three out of 393 patients (0.76%) who did not progress (estimated risk ratio 23.6, p = 0.0002). The cumulative ipsilateral stroke rate using life table methods was 0.22% at 1 year, 1% at 2 years and 2.4% at 3 years. In a large cohort of asymptomatic patients, the frequency of progression of 60-79% internal carotid artery stenosis was 5% at 1 year, 11% at 2 years and 20% at 3 years. Patients who progressed were more likely to have symptoms, but the rate of unheralded stroke was relatively low over a 3-year time period. Surveillance carotid ultrasound examinations should be performed in patients with moderate carotid stenosis. Because of the lack of clear benefit, carotid endarterectomy for asymptomatic 60-79% internal carotid artery stenosis cannot be justified.
本研究的目的是确定颈动脉狭窄程度的进展速度，并确定一组至少有一侧颈内动脉中度狭窄的无症状患者继续观察的风险。1989年至1994年期间，在作者所在的血管实验室进行的双功超声检查中，发现2130例患者至少有一侧颈内动脉狭窄60%-79%。其中，465例患者（255例男性，210例女性）无症状且接受了不止一次超声检查，他们构成了这项回顾性研究的基础。平均年龄±标准差为68.8±9.0岁。超声检查的平均次数±标准差为3.1±1.4次（范围为2-11次）。平均随访时间±标准差为24.4±17.6个月（范围为2-79个月）。在随访期间，72例患者（15.5%）进展为80%-99%狭窄（n=71）或闭塞（n=1）。采用寿命表法估计的1年、2年和3年进展患者百分比分别为5±1%、11±2%和20±3%。男性和女性的进展速度在统计学上无显著差异。21例患者发生了同侧迟发性短暂性脑缺血发作（TIA）或中风。进展的72例患者中有5例（6.9%）发生了同侧迟发性TIA，而未进展的393例患者中有9例（2.3%）发生了同侧迟发性TIA（估计风险比为16.1，P=0.0001）。进展的72例患者中有4例（5.6%）发生了同侧迟发性中风，而未进展的393例患者中有3例（0.76%）发生了同侧迟发性中风（估计风险比为23.6，P=0.0002）。采用寿命表法计算的同侧累积中风率在1年时为0.22%，2年时为1%，3年时为2.4%。在一大组无症状患者中，60%-79%颈内动脉狭窄的进展频率在1年时为5%，2年时为11%，3年时为20%。进展的患者更有可能出现症状，但在3年时间内未被察觉的中风发生率相对较低。对于中度颈动脉狭窄患者应进行监测性颈动脉超声检查。由于缺乏明确的益处，对于无症状的60%-79%颈内动脉狭窄患者行颈动脉内膜切除术是不合理的。
