Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan; Department of Vascular Surgery, Beppu Medical Center, Beppu, Japan.
Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
J Vasc Surg. 2020 Aug;72(2):541-548.e1. doi: 10.1016/j.jvs.2019.09.062. Epub 2020 Jan 21.
The management of type II endoleak (T2E) remains controversial because of the heterogeneous outcome. For blood-based screening to detect malignant T2E, we focused on platelets after endovascular aneurysm repair (EVAR) and compared them with the prognosis of T2Es.
From 2007 to 2015, there were 249 patients treated with EVAR for abdominal aortic aneurysm who were evaluated retrospectively. The mean follow-up period was 3.5 ± 0.2 years. T2Es that had aneurysm sac enlargement or converted to type I or type III endoleak were defined as malignant; the other T2Es were considered benign. Cases without any complications, including T2E, were defined as completed. We compared the platelet count on postoperative days (PODs) 1 to 7 with preoperative baseline values among the three groups. Sequentially, we calculated the cutoff of the platelet ratio on POD 7 to the baseline value in relation to malignant T2E using receiver operating characteristic analysis, and the cutoff ratio was 113% (sensitivity, 79%; specificity, 58%). We then reclassified T2E patients into T2E-high platelet (T2E-HP; ≥113%) or T2E-low platelet (T2E-LP; <113%) groups. The influence of platelets on T2E was evaluated with reintervention rate and cumulative aneurysm sac enlargement rate using the Kaplan-Meier method.
T2Es were found in 70 patients (28%), and 179 patients were assigned to the completed group. Malignant and benign T2Es were found in 33 and 37 patients, respectively. No difference was found in the preoperative baseline values. On POD 7, the platelet count in the malignant T2E group was significantly lower than that in the completed and benign T2E groups (168 × 10/μL vs 207 × 10/μL and 201 × 10/μL; P = .0124). Then, 27 and 43 patients were assigned to the T2E-HP and T2E-LP groups, respectively. The reintervention-free survival rate in the T2E-LP group was lower than that in the completed group (at 3 years, 66.4% ± 8.0% vs 71.9% ± 4.0%; P = .0031). Among T2E patients, the cumulative aneurysm sac enlargement rates in the T2E-LP group were significantly higher than those in the T2E-HP group (at 3 years, 34.6% ± 8.2% vs 20.6% ± 8.2%; P = .0105). Univariate Cox proportional hazards analysis for the cumulative aneurysm sac enlargement rates among T2E patients showed that sex, dual antiplatelet therapy, and lower platelet ratio (<113%) were significant predictors; multivariate analysis showed that T2E-LP was the only significant predictor (hazard ratio, 2.60; P = .0355).
The platelet count of patients with malignant T2Es on POD 7 was definitively lower than that of patients with completed EVAR or with benign T2Es. The lower platelet count on POD 7 could be a risk factor for aneurysm sac enlargement among patients with T2Es.
由于结局存在异质性，因此，II 型内漏（T2E）的处理仍存在争议。为了通过血液筛查检测恶性 T2E，我们重点关注血管内动脉瘤修复（EVAR）后的血小板，并将其与 T2E 的预后进行了比较。
回顾性分析了 2007 年至 2015 年间接受 EVAR 治疗的 249 例腹主动脉瘤患者。平均随访时间为 3.5±0.2 年。如果动脉瘤囊增大或转变为 I 型或 III 型内漏，则定义为恶性 T2E；其他 T2E 被认为是良性的。没有任何并发症（包括 T2E）的病例被定义为完成。我们比较了三组患者术后第 1 至 7 天的血小板计数与术前基线值。然后，我们使用接收者操作特征分析计算术后第 7 天血小板比率与基线值的截断值与恶性 T2E 的关系，截断值为 113%（敏感性，79%；特异性，58%）。然后，我们将 T2E 患者重新分为 T2E-高血小板（T2E-HP；≥113%）或 T2E-低血小板（T2E-LP；<113%）组。我们使用 Kaplan-Meier 方法评估血小板对 T2E 的影响，即再干预率和累积动脉瘤囊扩大率。
发现 70 例患者（28%）存在 T2E，179 例患者被分配到完成组。33 例患者为恶性 T2E，37 例患者为良性 T2E。术前基线值无差异。术后第 7 天，恶性 T2E 组的血小板计数明显低于完成组和良性 T2E 组（168×10/μL 比 207×10/μL 和 201×10/μL；P=.0124）。然后，将 27 例和 43 例患者分别分配到 T2E-HP 和 T2E-LP 组。T2E-LP 组的无再干预生存率低于完成组（3 年时，66.4%±8.0%比 71.9%±4.0%；P=.0031）。在 T2E 患者中，T2E-LP 组的累积动脉瘤囊扩大率明显高于 T2E-HP 组（3 年时，34.6%±8.2%比 20.6%±8.2%；P=.0105）。对 T2E 患者的累积动脉瘤囊扩大率进行单因素 Cox 比例风险分析显示，性别、双联抗血小板治疗和较低的血小板比值（<113%）是显著的预测因素；多因素分析显示，T2E-LP 是唯一显著的预测因素（风险比，2.60；P=.0355）。
术后第 7 天恶性 T2E 患者的血小板计数明显低于完成 EVAR 或良性 T2E 的患者。术后第 7 天的血小板计数降低可能是 T2E 患者动脉瘤囊扩大的危险因素。
