Trends in Utilization of Completion Imaging after Lower Extremity Bypass and Its Association with Major Adverse Limb Events and Loss of Primary Patency

Abstract

Failure following lower extremity bypasses (LEBs) isoften secondary to technical defects. Despite traditional teachings, routine use of completion imaging (CI) in LEB has been debated. This study assesses national trends of CI following LEBs and the association of routine CI with 1-year major adverse limb events (MALE) and 1-year loss of primary patency (LPP). The Vascular Quality Initiative (VQI) LEB dataset from 2003-2020 was queried for patients who underwent elective bypass for occlusive disease. The cohort was divided based on surgeons' CI strategy at time of LEB, categorized as routine (≥80% of cases/year), selective (<80% of cases/year), or never. The cohort was further stratified by surgeon volume category [low (<25th percentile), medium (25th-75th percentile), or high (>75th percentile)]. The primary outcomes were 1-year MALE-free survival and 1-year loss of primary patency (LPP)-free survival. Our secondary outcomes were temporal trends in CI use and temporal trends in 1-year MALE rates. Standard statistical methods were utilized. We identified 37,919 LEBs; 7,143 in routine CI strategy cohort, 22,157 selective CI and 8,619 in never CI. Patients in the 3 cohorts had comparable baseline demographics and indications for bypass. There was a significant decrease in CI utilization from 77.2% in 2003 to 32.0% in 2020 (P<0.001). Similar trends in CI use were observed in patients who underwent bypass to tibial outflows (86.0% in 2003 vs. 36.9% in 2020; P<0.001). While the use of CI has decreased over time, 1-year MALE rates have increased from 44.4% in 2003 to 50.4% in 2020 (P<0.001). On multivariate COX regression, however, no significant associations between CI use or CI strategy and risk of 1-year MALE or LPP was found. Procedures performed by high-volume surgeons carried a lower risk of 1-year MALE (HR: 0.84; 95% CI [0.75-0.95]; P=0.006) and LPP (HR:0.83; 95% CI [0.71-0.97]; P<0.001) compared to low-volume surgeons. Repeat adjusted analyses showed no association between CI (use or strategy) and our primary outcomes when the subgroups with tibial outflows were analyzed. Similarly, no associations were found between CI (use or strategy) and our primary outcomes when the subgroups based on surgeons' CI volume were evaluated. The use of CI, for both proximal and distal target bypasses, has decreased over time while 1-year MALE rates have increased. Adjusted analyses indicate no association between CI use and improved MALE or LPP survival at 1year and all CI strategies were found to have equivalent outcomes.