UC San Diego

Background

Chronic limb-threatening ischemia (CLTI) in patients with chronic kidney disease (CKD) has a high risk of poor outcomes. We aimed to compare the outcomes of lower extremity revascularization in patients with CLTI stratified by CKD severity in patients enrolled in the prospective, randomized Best Endovascular vs Best Surgical Therapy in Patients with CLTI (BEST-CLI) trial.

Methods

The BEST-CLI trial dataset was queried to categorize patients into three groups according to CKD stage. Group A includes non-CKD and CKD stages <3; group B includes stage 3 and stage 4 CKD patients; and group C includes stage 5 CKD and dialysis-dependent patients. Furthermore, spline modeling was performed across the range of estimated glomerular filtration rate (eGFR, mL/min/1.73 m²) observed in study participants to identify a threshold eGFR that impacted the primary trial outcomes: major adverse limb events (MALEs; defined as above-ankle amputation or major reintervention) or all-cause mortality, by surgical or endovascular revascularization (as-treated analysis). Kaplan-Meier and multivariate Cox regression analyses were used to assess association of CKD risk groups with the outcomes.

Results

A total of 1797 patients were included. Group C patients had double the risk of amputation (hazard ratio [HR], 2.13; P < .001), MALE, or all-cause mortality (HR, 2.05; P < .001) and more than triple the risk of all-cause mortality (HR, 3.40; P < .001) compared with group A. In dialysis-dependent patients, endovascular therapy was associated with better survival, but twice the risk of reintervention compared with surgical revascularization. According to spline model analysis, hazard of MALE or all-cause mortality increased sharply at eGFR <30. The hazard ratios for eGFR <30 vs ≥60 were 2.03 (95% confidence interval [CI], 1.68-2.43; P < .001) and 3.46 (95% CI, 2.80-4.27; P < .001) for MALE and mortality, respectively. At eGFR <30, there was no difference in the primary outcome by treatment received (surgical or endovascular revascularization).

Conclusions

The progressive nature of renal impairment in patients with CLTI threatens their survival and limb salvage and may reduce the relative benefit of open vs endovascular revascularization seen in the overall BEST-CLI trial population. In dialysis-dependent patients, endovascular therapy was associated with lower mortality but increased reintervention rate.