Department of Vascular and Endovascular Surgery, First Medical Center of Chinese PLA General Hospital, Beijing, China.
Research Platform for Minimally Invasive Cardiovascular Surgery, Beijing Key Laboratory, Beijing, China.
J Endovasc Ther. 2020 Apr;27(2):211-220. doi: 10.1177/1526602820904164. Epub 2020 Feb 6.
To examine the association between the extent of stent-graft coverage and thoracic aortic expansion after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection. A retrospective analysis was conducted of 201 patients (mean age 52.4±11.5 years; 178 men) with acute (135, 67.2%) or chronic (66, 32.8%) type B aortic dissection who underwent TEVAR at 4 medical centers. The mean stent-graft length was 157.1±33.3 mm. The percentage of stented descending aorta (PSDA) represented the extent of stent-graft coverage. After using restricted cubic smoothing spline plots to confirm the roughly linear relationship between PSDA and the risk of thoracic aortic expansion, patients were stratified into 2 groups on the median PSDA: the lower group (≤31.3%) and the higher group (>31.3%). Thoracic aortic expansion was defined as a ≥20% increase in the total thoracic aortic volume on the most recent postoperative computed tomography angiography scan compared with the preoperative measurement. The Kaplan-Meier method was used to estimate the cumulative freedom from thoracic aortic expansion after TEVAR; estimates are given with the 95% confidence interval (CI). A multivariable Cox proportional hazards model was used to analyze any independent association of the PSDA as a continuous or categorical variable with the risk of thoracic aortic expansion; results are presented as the hazard ratio (HR) and 95% CI. No patients developed symptoms of spinal cord ischemia during hospitalization. Over a median 12.4 months of imaging follow-up, 34 (16.9%) patients developed thoracic aortic expansion. The estimate of freedom from thoracic aortic expansion at 12 months for the overall PSDA was 84.0% (95% CI 77.8% to 88.6%); between the groups, the freedom from thoracic aortic expansion estimate for the PSDA ≤31.3% group was significantly lower than in the higher group (p=0.032). Regression analysis showed no significant association between the risk of thoracic aortic expansion and the PSDA as a continuous variable (HR 0.97, 95% CI 0.91 to 1.03, p=0.288); however, analyzing the PSDA as a categorical variable indicated a significantly lower risk of thoracic aortic expansion for the PSDA >31.3% group (HR 0.46, 95% CI 0.22 to 0.95, p=0.036) after adjusting for a variety of demographic and anatomical characteristics. More extensive stent-graft coverage appears to improve thoracic aortic remodeling after TEVAR. However, the clinician should balance the benefit of extensive stent-graft coverage and its related risk of spinal cord ischemia.
为了研究支架覆盖程度与胸主动脉腔内修复术（TEVAR）治疗 B 型主动脉夹层后胸主动脉扩张之间的关系。对 4 家医疗中心的 201 名急性（135 例，67.2%）或慢性（66 例，32.8%）B 型主动脉夹层患者进行了回顾性分析。支架移植物的平均长度为 157.1±33.3mm。支架降主动脉覆盖百分比（PSDA）代表了支架覆盖的程度。使用限制立方平滑样条图确认 PSDA 与胸主动脉扩张风险之间的大致线性关系后，根据 PSDA 的中位数将患者分为两组：低组（≤31.3%）和高组（>31.3%）。胸主动脉扩张定义为与术前测量相比，最近的术后 CT 血管造影扫描中总胸主动脉体积增加≥20%。使用 Kaplan-Meier 方法估计 TEVAR 后胸主动脉扩张的累积无事件率；估计值带有 95%置信区间（CI）。使用多变量 Cox 比例风险模型分析 PSDA 作为连续或分类变量与胸主动脉扩张风险之间的任何独立关联；结果表示为风险比（HR）和 95%CI。住院期间无患者出现脊髓缺血症状。在中位 12.4 个月的影像学随访中，34 名（16.9%）患者出现胸主动脉扩张。总体 PSDA 下 12 个月的胸主动脉扩张无事件率估计值为 84.0%（95%CI 77.8%至 88.6%）；两组之间，PSDA≤31.3%组的胸主动脉扩张无事件率明显低于高组（p=0.032）。回归分析显示，PSDA 作为连续变量与胸主动脉扩张风险之间无显著关联（HR 0.97，95%CI 0.91 至 1.03，p=0.288）；然而，将 PSDA 作为分类变量进行分析表明，PSDA>31.3%组的胸主动脉扩张风险显著降低（HR 0.46，95%CI 0.22 至 0.95，p=0.036），调整了多种人口统计学和解剖学特征后。更广泛的支架移植物覆盖似乎可以改善 TEVAR 后的胸主动脉重塑。然而，临床医生应该权衡广泛的支架移植物覆盖的益处及其相关的脊髓缺血风险。
