Anticoagulation does not improve limb outcomes after lower extremity cryopreserved vein bypass

Cryopreserved vein grafts serve as alternative conduits for infrainguinal bypass when autogenous vein is unavailable or inadequate. Anticoagulation has been advocated to improve outcomes, but published studies demonstrate conflicting results. We assessed the association of anticoagulation on outcomes after infrainguinal bypass with cryopreserved vein in patients with chronic limb-threatening ischemia.

The Vascular Quality Initiative was queried (2003-2022) for infrainguinal bypass performed using cryopreserved vein graft for chronic limb-threatening ischemia. Baseline characteristics, procedural details, and outcomes between those discharged with or without anticoagulation were recorded. Univariable, Kaplan-Meier, and multivariable analyses were performed.

There were 2336 patients who underwent an infrainguinal bypass with cryopreserved vein conduit. The average age was 70.6 years and 63.5% were male. Bypass targets were femoral/popliteal (27.5%) and tibial (72.5%). Indication for intervention included rest pain (25.7%) and tissue loss (74.3%). Patients were discharged with aspirin (80.1%), a P2Y12 inhibitor (45.6%), and anticoagulation (47.3%). Patients discharged on postoperative anticoagulation more often were treated for rest pain (28.1% vs 23.5%), had a tibial bypass target (78.4% vs 67.2%), and less often underwent endarterectomy (27.8% vs 34.2%) (all P < .05). Kaplan-Meier analysis at 1 year demonstrated that postoperative anticoagulation had similar freedom from loss of primary patency/death (28.9% vs 34.3%), major amputation/death (62.3% vs 63.8%), and reintervention/major amputation/death (50.6% vs 53.8%) (all P > .05), but higher survival (85.1% vs 81.7%; P = .03). Multivariable analysis at 1 year demonstrated that postoperative anticoagulation had a similar likelihood for loss of primary patency/death (hazard ratio [HR], 0.95; 95% confidence interval [CI], 0.83.-1.09), major amputation/death (HR, 0.88; 95% CI, 0.74-1.05), and reintervention/major amputation/death (HR, 0.93; 95% CI, 0.79-1.08) (all P > .05), but a lower likelihood for death (HR, 0.59; 95% CI, 0.46-0.74; P < .001) compared with no anticoagulation. Postoperative aspirin was associated with a lower likelihood for amputation/death (HR, 0.74; 95% CI, 0.61-0.91; P = .003) and reintervention/major amputation/death (HR, 0.76; 95% CI, 0.64-0.9; P = .002). Postoperative P2Y12 inhibitor was associated with decreased likelihood for amputation/death (HR, 0.75; 95% CI, 0.63-0.9; P = .002) and reintervention/major amputation/death (HR, 0.78; 95% CI, 0.67-0.91; P = .001). Results were similar when analyzing patients who were not on anticoagulation preoperatively.

Postoperative anticoagulation after infrainguinal bypass using cryopreserved vein did not affect patency or limb salvage. Antiplatelet agents were associated with improved outcomes. Overall patency and limb salvage rates at 1 year were poor. When cryopreserved vein is used, surgeons should consider antiplatelet therapy for cryopreserved graft patency rather than anticoagulation.