Bypass with Prosthetic Graft Is Superior to Endovascular Therapy in Diabetic Patients with Chronic Limb-threatening Ischemia

Abstract

Bypass with saphenous vein graft (SVG) is considered the standard of care in all patients with chronic limb-threatening ischemia (CLTI), including patients with diabetes mellitus (DM). However, when an autogenous graft is not available, the options are bypass with a prosthetic graft (BPG) or endovascular therapy (ET). In the present study, we aimed to compare midterm outcomes of BPG to ET in patients with DM using data from Vascular Quality Initiative Medicare-Linked (Vascular Implant Surveillance and Interventional Outcomes Network) database. We queried the Vascular Implant Surveillance and Interventional Outcomes Network database for diabetic patients who underwent lower extremity revascularization for CLTI from 2003 to 2019. DM was either insulin-dependent DM (IDDM) or noninsulin-dependent DM (NIDDM). Patients undergoing bypass with SVG and grafts other than prosthetic grafts were excluded. Moreover, patients with prior ipsilateral interventions/major amputation and concomitant suprainguinal procedures were excluded. The primary outcome was amputation-free survival. The secondary outcomes included overall survival, limb salvage, and freedom from target lesion reintervention. Kaplan-Meier Estimates and Cox regression were used for analysis. The study included two cohorts: BPG (n = 1941; 8.6%) and ET (n = 20,703; 91.4%). Patients undergoing ET were more likely to have IDDM (NIDDM on diet, 8.8%; NIDDM on oral medications, 24.7%; IDDM, 66.5%) than the patients undergoing BPG (NIDDM on diet, 9.0%; NIDDM on oral medications, 31.7%; IDDM, 59.3%; P < .001). Patients who underwent BPG had higher amputation-free survival at 1 year (65.8% vs 59.1%; P < .001) and 4 years (34.1% vs 29.4%; P < .001; Figure). After adjusting for potential confounders, ET was associated with higher rates of amputation or death at 1 year (adjusted hazard ratio [aHR], 1.16; 95% confidence interval [CI], 1.06-1.27; P = .001) and 4 years (aHR, 1.10; 95% CI, 1.03-1.19; P = .007) compared to bypass with prosthetic graft. Moreover, ET was associated with higher 4-year mortality (aHR, 1.10; 95% CI, 1.02-1.19; P = .019) and target lesion reintervention (aHR, 1.35; 95% CI, 1.23-1.48, P < .001) compared to BPG. On subanalysis of the data stratified by the type of treatment used for DM, ET was associated with increased risk of amputation or death in 1 year and 4 years only in patients with NIDDM (on diet or oral medications) but not IDDM (Table). Despite recent evidence showing no advantage of using alternative conduit to SVG for bypass over endovascular therapy, this study supports the use of prosthetics grafts over ET for the treatment of CLTI in Medicare beneficiaries with DM and particularly in NIDDM when SVG is not adequate. Further prospective studies are necessary to confirm our findings.TableMultivariate Cox regression analysis of bypass with prosthetic graft vs endovascular therapy in diabetic patients with chronic limb-threatening ischemia (CLTI) (Reference = bypass with prosthetic graft)Outcome1 Year4 YearsET, aHR (95% CI)P valueET, aHR (95% CI)P valueAll diabetic patients Major amputation or death1.16 (1.06-1.27).0011.10 (1.03-1.19).007 Mortality1.14 (1.02-1.28).0201.10 (1.02-1.19).019 Major amputation1.17 (1.01-1.34).0301.07 (0.95-1.21).278 Reintervention on target lesion1.50 (1.33-1.70)<.0011.35 (1.23-1.48)<.001Subanalysis NIDDM on dietMajor amputation or death1.60 (1.12-2.29).0101.36 (1.05-1.75).019Mortality1.34 (0.92-1.94).1231.21 (0.93-1.57).154Major amputation1.55 (0.90-2.68).1161.29 (0.83-2.01).253Reintervention on target lesion3.06 (1.88-4.98)<.0012.13 (1.46-3.12)<.001 NIDDM on oral medicationsMajor amputation or death1.34 (1.10-1.62).0031.15 (1.01-1.32).042Mortality1.22 (0.95-1.57).1181.11 (0.94-1.30).211Major amputation1.72 (1.27-2.32)<.0011.37 (1.06-1.76).017Reintervention on target lesion1.48 (1.20-1.83)<.0011.46 (1.23-1.75)<.001 IDDMMajor amputation or death1.06 (0.95-1.19).2931.05 (0.96-1.15).302Mortality1.09 (0.95-1.26).2171.07 (0.96-1.18).220Major amputation1.01 (0.86-1.20).8740.97 (0.84-1.12).701Reintervention on target lesion1.42 (1.22-1.64)<.0011.25 (1.12-1.40)<.001aHR, Adjusted hazard ratio; CI, confidence interval; ET, endovascular therapy; IDDM, insulin-dependent diabetes mellitus; NIDDM, noninsulin-dependent diabetes mellitus. Open table in a new tab