Contextualizing the BEST-CLI Trial Results in Clinical Practice

Chronic limb-threatening ischemia (CLTI) is associated with poor long-term outcomes. Although prompt revascularization is recommended, the optimal revascularization strategy remains uncertain. The BEST-CLI trial compared endovascular and open surgical revascularization for CLTI, but the generalizability of this study to the clinical population with CLTI has not been evaluated.

We included Medicare beneficiaries aged 65-85 years with CLTI who underwent revascularization and would be eligible for enrollment in BEST-CLI between 2016 and 2019. The primary exposure was type of revascularization (endovascular vs autologous graft [cohort 1] vs nonautologous graft [cohort 2]), and the primary outcome was a composite of major adverse limb events (MALE) and death. MALE included above-ankle amputation and major intervention, which was defined as new bypass of index limb, thrombectomy, or thrombolysis.

A total of 66,153 patients were included in this study (10,125 autologous grafts; 7867 nonautologous grafts; 48,161 endovascular). Compared with those enrolled in BEST-CLI cohort 1, patients in this study were older (mean age, 73.5 ± 5.7 vs 69.9 ± 9.9 years), more likely to be female (38.3% [22,340/58,286] vs 28.5% [408/1434]), and presented with more comorbidities. Endovascular operators for the study population vs BEST-CLI cohort 1 were less likely to be surgeons (55.9% [26,924/48,148] vs 73.0% [520/708]) and more likely to be cardiologists (25.5% [5900/48,148] vs 14.5% [103/78]). When assessing long-term outcomes, the crude risk of death or MALE in this cohort was higher with surgery (56.6% autologous grafts vs 42.6% BEST-CLI cohort 1 at a median of follow-up 2.7 years; 51.6% nonautologous grafts vs 42.8% BEST-CLI cohort 2 at a median follow-up of 1.6 years) but similar with the endovascular cohort (58.7% Medicare vs 57.4% cohort 1 at 2.7 years; 47.0% Medicare vs 47.7% cohort 2 at 1.6 years). Of those who received endovascular treatment, the risk of incident major intervention was less than half in this cohort compared with the trial cohort (10.0% Medicare vs 23.5% cohort 1 at 2.7 years; 8.6% Medicare vs 25.6% cohort 2 at 1.6 years), although technical endovascular failures were not captured.

These results suggest that the findings of the BEST-CLI trial may not be applicable to the entirety of the Medicare population of patients with CLTI undergoing revascularization.