Cardiovascular Center, Semmelweis University, Budapest, Hungary.
Health Services Management Training Centre, Semmelweis University, Budapest, Hungary.
Ann Vasc Surg. 2024 Nov;108:410-418. doi: 10.1016/j.avsg.2024.05.021. Epub 2024 Jul 14.
To evaluate the impact of anatomical variations in the Circle of Willis (CoW) on immediate neurological events (INEs) after carotid endarterectomy (CEA) without shunting in patients with contralateral carotid occlusion (CCO).
Single-center retrospective study. Patient's demographic and clinical outcomes data were prospectively collected. CoW segments were reviewed retrospectively. Between January 2013 and May 2018, 2090 patients underwent CEA under general anesthesia, CCO was found in 113 (5.4%) patients. CoW segments were classified as normal, hypoplastic (diameter ˂0.8 mm), or absent based on computed tomography angiography. We studied the CoW segments as 2 collateral networks connecting the basilar artery and the ipsilateral middle cerebral artery: a short semicircle (first segment of the ipsilateral posterior cerebral artery [P1] and posterior communicating artery [Pcom] segment) and a long semicircle (contralateral P1, Pcom, and both first segments of the anterior cerebri artery (A1) anterior communicating artery (Acom)). INE was defined as any transient ischemic attack or stroke diagnosed immediately after the procedure.
Out of the 113 patients, 46 underwent endarterectomy with shunting. We further excluded 16 patients from the assessment of the CoW due to unavailability or inadequate quality of computed tomography angiography. Of the 113 patients, 2 had strokes, 1 with shunting that occurred hrs after surgery. Besides the other stroke case, 4 INE were observed, all without the use of a shunt. Of the 51 patients with CoW assessment, 10 (19.6%) had a complete CoW, while 21 (41.2%) patients had only 1 semicircle intact (10 short and 11 long intact semicircles), and none of these patients experienced an INE. A total of 20 (39%) patients had both the long and short semicircles incomplete, of which 4 (7.8%) cases had an INE. In all INE cases, at least 1 of the Pcom was absent or hypoplastic. The absence of both Pcom was a strong predictor of incident INE [odds ratio = 11.10 (confidence interval: 1.04-118.60)] for INE.
Patients with CCO and insufficient CoW collateral flow support are at an increased risk of INE, including stroke, in the absence of shunt protection during CEA cross-clamping. Shunting should always be considered when the collateral flow between the ipsilateral middle cerebral artery and the basilar artery is compromised in CCO patients.
评估在没有分流的情况下，颈总动脉闭塞（CCO）患者行颈动脉内膜切除术（CEA）后 Willis 环（CoW）解剖变异对即刻神经事件（INE）的影响。
单中心回顾性研究。前瞻性收集患者的人口统计学和临床结局数据。回顾性分析 CoW 节段。2013 年 1 月至 2018 年 5 月，2090 例全麻下行 CEA 患者中，发现 113 例（5.4%）患者存在 CCO。根据 CT 血管造影，CoW 节段分为正常、发育不良（直径＜0.8mm）或缺失。我们将 CoW 分为连接基底动脉和同侧大脑中动脉的 2 个侧支网络：短半圆（同侧大脑后动脉 [P1]和后交通动脉 [Pcom]段的第一段）和长半圆（对侧 P1、Pcom 和两侧大脑前动脉 [A1]前交通动脉 [Acom]的第一段）。INE 定义为任何在手术后立即诊断出的短暂性脑缺血发作或中风。
113 例患者中，46 例行带分流的内膜切除术。由于 CT 血管造影不可用或质量不佳，我们进一步排除了 16 例患者的 CoW 评估。在 113 例患者中，2 例发生中风，1 例在手术后数小时发生中风，有分流。除了其他中风病例外，还观察到 4 例 INE，均未使用分流器。在 51 例 CoW 评估患者中，10 例（19.6%）存在完整的 CoW，21 例（41.2%）患者仅存在 1 个半圆完整（10 个短半圆和 11 个长半圆），这些患者均未发生 INE。共有 20 例（39%）患者的长、短半圆均不完整，其中 4 例（7.8%）发生 INE。所有 INE 病例中，至少有 1 个 Pcom 缺失或发育不良。Pcom 完全缺失是 CEA 夹闭期间无分流保护时发生 INE 的强预测因子[比值比=11.10（95%置信区间：1.04-118.60）]。
在 CCO 患者中，当同侧大脑中动脉和基底动脉之间的侧支血流受到损害时，没有分流保护，这些患者发生 INE（包括中风）的风险增加。在 CCO 患者中，如果发现 Willis 环的侧支血流代偿不足，应始终考虑分流。
