Gordon I L, Stemmer E A, Wilson S E
Department of Surgery, University of California Irvine Medical Center, Orange 92668, USA.
J Vasc Surg. 1995 Oct;22(4):349-58; discussion 358-60. doi: 10.1016/s0741-5214(95)70001-3.
We wanted to characterize the immediate effect of endarterectomy on flow of the arteries composing the extracranial carotid artery system.
Transit time ultrasound probes were used to measure flow through the carotid bifurcation in 48 patients undergoing endarterectomy. Maximum single-diameter stenosis affecting the internal carotid artery (ICA) was determined by angiography. The significance of differences between means were determined by t tests and analysis of variance; linear and nonparametric correlation analyses were also applied to analyze the relation between stenosis and several flow-derived parameters.
Common carotid artery flow significantly increased (p = 0.0043) from a mean value of 264 +/- 99 ml/min to 314 +/- 98 ml/min, corresponding to an average percent increase of 34.3% +/- 71.3%. ICA flow increased from 128 +/- 69 ml/min to 173 +/- 66 ml/min (p < 0.0001), with an average percent increase of 74.9% +/- 114.9%. External carotid artery (ECA) flow decreased from 129 +/- 61 ml/min to 106 +/- 49 ml/min (p = 0.0098), representing an average percent decrease of -5.2% +/- 48.2%. The difference between ECA and ICA mean flow changes is highly significant (p < 0.001). The percent change in ECA flow did not correlate with preoperative stenosis. We noted, however, a positive correlation between stenosis and the ECA/ICA flow ratio before endarterectomy (Spearman r = 0.31, p = 0.032), indicating that more severe stenosis led to a greater distribution of blood into the ECA. The ECA/ICA flow ratio fell from an initial value (ECFbef/ICFbef) of 1.52 +/- 1.74 before endarterectomy to 0.69 +/- 0.37 (ECFaft/ICFaft) after endarterectomy (p = 0.0006).
The data are consistent, with the ECA being an important collateral path for cerebral perfusion when ICA stenosis exists. When endarterectomy relieves bifurcation stenosis, common carotid artery blood flow is redistributed preferentially to the ICA at the expense of ECA flow, consistent with a change in the relative resistances of the two vessels resulting from operative reconstruction.
我们旨在描述动脉内膜切除术对构成颅外颈动脉系统的动脉血流的即时影响。
使用经颅时间超声探头测量48例行动脉内膜切除术患者的颈动脉分叉处血流。通过血管造影确定影响颈内动脉（ICA）的最大单径狭窄程度。采用t检验和方差分析确定均值差异的显著性；还应用线性和非参数相关分析来分析狭窄与几个血流衍生参数之间的关系。
颈总动脉血流显著增加（p = 0.0043），从平均值264±99毫升/分钟增至314±98毫升/分钟，平均增加百分比为34.3%±71.3%。ICA血流从128±69毫升/分钟增至173±66毫升/分钟（p < 0.0001），平均增加百分比为74.9%±114.9%。颈外动脉（ECA）血流从129±61毫升/分钟降至106±49毫升/分钟（p = 0.0098），平均降低百分比为 -5.2%±48.2%。ECA和ICA平均血流变化之间的差异非常显著（p < 0.001）。ECA血流的百分比变化与术前狭窄程度无关。然而，我们注意到动脉内膜切除术前行狭窄程度与ECA/ICA血流比值呈正相关（Spearman相关系数r = 0.31，p = 0.032），这表明更严重的狭窄导致更多血液流向ECA。ECA/ICA血流比值从动脉内膜切除术前的初始值（ECFbef/ICFbef）1.52±1.74降至动脉内膜切除术后的0.69±0.37（ECFaft/ICFaft）（p = 0.0006）。
这些数据表明，当存在ICA狭窄时，ECA是脑灌注的重要侧支路径。当动脉内膜切除术解除分叉处狭窄时，颈总动脉血流优先重新分配至ICA，而以ECA血流为代价，这与手术重建导致的两根血管相对阻力变化一致。
