Abstract：
BACKGROUND: Occlusion after infra-inguinal bypass surgery for peripheral artery disease is a major complication with potentially devastating consequences. In this descriptive analysis, we sought to describe the natural history and explore factors associated with long-term major amputation-free survival following occlusion of a first-time infra-inguinal bypass.
METHODS: Using a prospective database from a tertiary care vascular center, we conducted a retrospective cohort study of all patients with peripheral artery disease who underwent a first-time infra-inguinal bypass and subsequently suffered a graft occlusion (1997-2021). The primary outcome was longitudinal rate of major amputation-free survival after bypass occlusion. Cox proportional hazard models were used to generate hazard ratios (HRs) and 95% confidence intervals (CIs) to explore predictors of outcomes.
RESULTS: Of the 1318 first-time infra-inguinal bypass surgeries performed over the study period, 255 bypasses occluded and were included in our analysis. Mean age was 66.7 (12.6) years, 40.4% were female, and indication for index bypass was chronic limb threatening ischemia (CLTI) in 89.8% (n = 229). 48.2% (n = 123) of index bypass conduits used great saphenous vein, 29.0% (n = 74) prosthetic graft, and 22.8% (n = 58) an alternative conduit. Median (interquartile range) time to bypass occlusion was 6.8 (2.3-19.0) months, and patients were followed for median of 4.3 (1.7-8.1) years after bypass occlusion. Following occlusion, 38.04% underwent no revascularization, 32.94% graft salvage procedure, 25.1% new bypass, and 3.92% native artery recanalization. Major amputation-free survival following occlusion was 56.9% (50.6%-62.8%) at 1 y, 37.1% (31%-43.3%) at 5 y, and 17.2% (11.9%-23.2%) at 10 y. In multivariable analysis, factors associated with lower amputation-free survival were older age, female sex, advanced cardiorenal comorbidities, CLTI at index procedure, CLTI at time of occlusion, and distal index bypass outflow. Initial treatment after occlusion with both a new surgical bypass (HR 0.44, CI: 0.29-0.67) or a graft salvage procedure (HR 0.56, CI: 0.38-0.82) showed improved amputation-free survival. One-year rate of major amputation or death were 59.8% (50.0%-69.6%) for those who underwent no revascularization, 37.9% (28.7%-49.0%) for graft salvage, and 26.7% (17.6%-39.5%) for new bypass.
CONCLUSIONS: Long-term major amputation-free survival is low after occlusion of a first-time infra-inguinal bypass. While several nonmodifiable risk factors were associated with lower amputation-free survival, treatment after graft occlusion with either a new bypass or a graft salvage procedure may improve longitudinal outcomes.
METHODS: Using a prospective database from a tertiary care vascular center, we conducted a retrospective cohort study of all patients with peripheral artery disease who underwent a first-time infra-inguinal bypass and subsequently suffered a graft occlusion (1997-2021). The primary outcome was longitudinal rate of major amputation-free survival after bypass occlusion. Cox proportional hazard models were used to generate hazard ratios (HRs) and 95% confidence intervals (CIs) to explore predictors of outcomes.
RESULTS: Of the 1318 first-time infra-inguinal bypass surgeries performed over the study period, 255 bypasses occluded and were included in our analysis. Mean age was 66.7 (12.6) years, 40.4% were female, and indication for index bypass was chronic limb threatening ischemia (CLTI) in 89.8% (n = 229). 48.2% (n = 123) of index bypass conduits used great saphenous vein, 29.0% (n = 74) prosthetic graft, and 22.8% (n = 58) an alternative conduit. Median (interquartile range) time to bypass occlusion was 6.8 (2.3-19.0) months, and patients were followed for median of 4.3 (1.7-8.1) years after bypass occlusion. Following occlusion, 38.04% underwent no revascularization, 32.94% graft salvage procedure, 25.1% new bypass, and 3.92% native artery recanalization. Major amputation-free survival following occlusion was 56.9% (50.6%-62.8%) at 1 y, 37.1% (31%-43.3%) at 5 y, and 17.2% (11.9%-23.2%) at 10 y. In multivariable analysis, factors associated with lower amputation-free survival were older age, female sex, advanced cardiorenal comorbidities, CLTI at index procedure, CLTI at time of occlusion, and distal index bypass outflow. Initial treatment after occlusion with both a new surgical bypass (HR 0.44, CI: 0.29-0.67) or a graft salvage procedure (HR 0.56, CI: 0.38-0.82) showed improved amputation-free survival. One-year rate of major amputation or death were 59.8% (50.0%-69.6%) for those who underwent no revascularization, 37.9% (28.7%-49.0%) for graft salvage, and 26.7% (17.6%-39.5%) for new bypass.
CONCLUSIONS: Long-term major amputation-free survival is low after occlusion of a first-time infra-inguinal bypass. While several nonmodifiable risk factors were associated with lower amputation-free survival, treatment after graft occlusion with either a new bypass or a graft salvage procedure may improve longitudinal outcomes.
摘要：
背景：周围动脉疾病腹股沟下旁路手术后的阻塞是一种主要并发症，具有潜在的破坏性后果。在这种描述性分析中，我们试图描述患者的自然史,并探讨与首次腹股沟下搭桥术闭塞后长期无截肢生存相关的因素.
方法：使用三级护理血管中心的前瞻性数据库，我们进行了一项回顾性队列研究,对所有首次行腹股沟下分流术并随后发生移植物闭塞(1997~2021年)的外周动脉疾病患者进行了研究.主要结果是旁路闭塞后无截肢的纵向生存率。Cox比例风险模型用于生成风险比（HR）和95％置信区间（CI）以探索结果的预测因子。
结果：在研究期间进行的1318例首次腹股沟下旁路手术中，255个旁路阻塞，并包括在我们的分析中。平均年龄为66.7（12.6）岁，40.4%是女性，指征分流术为慢性威胁肢体缺血(CLTI)占89.8%(n=229)。48.2％（n=123）的索引旁路导管使用大隐静脉，29.0%(n=74)人工移植,和22.8%(n=58)的替代管道。旁路闭塞的中位数（四分位距）时间为6.8（2.3-19.0）个月，患者在旁路闭塞后中位随访4.3年(1.7-8.1年).遮挡后，38.04%未进行血运重建,32.94%的移植物抢救程序，25.1%新旁路,3.92%的天然动脉再通。闭塞后1年无主要截肢生存率为56.9％（50.6％-62.8％），5y时37.1%（31%-43.3%），10年时为17.2%(11.9%-23.2%)。在多变量分析中，与较低的无截肢生存率相关的因素是年龄较大，女性性别,晚期心肾合并症,CLTI在索引程序，CLTI在闭塞时，和远端索引旁路流出。新的手术搭桥（HR0.44，CI：0.29-0.67）或移植抢救程序（HR0.56，CI：0.38-0.82）闭塞后的初始治疗显示无截肢生存率提高。无血运重建者的一年大截肢或死亡率为59.8%(50.0%-69.6%),移植物抢救的37.9%(28.7%-49.0%)，和26.7%（17.6%-39.5%）的新旁路。
结论：首次腹股沟下搭桥术闭塞后，长期无截肢生存率较低。虽然一些不可改变的危险因素与较低的无截肢生存率相关，在移植物闭塞后,采用新的旁路或移植物抢救程序进行治疗可能会改善纵向结局.
方法：使用三级护理血管中心的前瞻性数据库，我们进行了一项回顾性队列研究,对所有首次行腹股沟下分流术并随后发生移植物闭塞(1997~2021年)的外周动脉疾病患者进行了研究.主要结果是旁路闭塞后无截肢的纵向生存率。Cox比例风险模型用于生成风险比（HR）和95％置信区间（CI）以探索结果的预测因子。
结果：在研究期间进行的1318例首次腹股沟下旁路手术中，255个旁路阻塞，并包括在我们的分析中。平均年龄为66.7（12.6）岁，40.4%是女性，指征分流术为慢性威胁肢体缺血(CLTI)占89.8%(n=229)。48.2％（n=123）的索引旁路导管使用大隐静脉，29.0%(n=74)人工移植,和22.8%(n=58)的替代管道。旁路闭塞的中位数（四分位距）时间为6.8（2.3-19.0）个月，患者在旁路闭塞后中位随访4.3年(1.7-8.1年).遮挡后，38.04%未进行血运重建,32.94%的移植物抢救程序，25.1%新旁路,3.92%的天然动脉再通。闭塞后1年无主要截肢生存率为56.9％（50.6％-62.8％），5y时37.1%（31%-43.3%），10年时为17.2%(11.9%-23.2%)。在多变量分析中，与较低的无截肢生存率相关的因素是年龄较大，女性性别,晚期心肾合并症,CLTI在索引程序，CLTI在闭塞时，和远端索引旁路流出。新的手术搭桥（HR0.44，CI：0.29-0.67）或移植抢救程序（HR0.56，CI：0.38-0.82）闭塞后的初始治疗显示无截肢生存率提高。无血运重建者的一年大截肢或死亡率为59.8%(50.0%-69.6%),移植物抢救的37.9%(28.7%-49.0%)，和26.7%（17.6%-39.5%）的新旁路。
结论：首次腹股沟下搭桥术闭塞后，长期无截肢生存率较低。虽然一些不可改变的危险因素与较低的无截肢生存率相关，在移植物闭塞后,采用新的旁路或移植物抢救程序进行治疗可能会改善纵向结局.
