Long-Term Results of Femorotibial Polytetrafluoroethylene Bypass with a Distal Vein Cuff for Critical Limb Ischemia

Heparin-Bonded Expanded Polytetrafluoroethylene Is a Solution for Infrapopliteal Revascularization in the Absence of an Adequate Autologous Vein Graft

BACKGROUND

To analyze the outcomes of heparin-bonded expanded polytetrafluoroethylene (HePTFE) graft as an alternative conduit in infrapopliteal revascularization of chronic limb-threatening ischemia (CLTI) in the absence of an autologous vein conduit.

METHODS

A single-center retrospective analysis of patients with CLTI submitted to infrapopliteal bypasses with autologous vein graft (VEIN group) or HePTFE graft (HePTFE group) was implemented. Primary end points were freedom from CLTI at 12 months and recurrence of CLTI at 3 years. Secondary end points included freedom from major amputation, amputation-free survival (AFS), survival, and primary (PP) and secondary patency (SP) rates at 3 years of follow-up.

RESULTS

A total of 348 limbs submitted to infrapopliteal bypasses, 214 with venous graft and 134 with HePTFE graft, were followed-up for a median of 25 months. Most patients of the HePTFE group were male (69%), with a median age of 76 years (interquartile range [IQR] 15). Fifty-nine percent of the limbs of the HePTFE group had Wound grade ≥2, being 46% of them infected. Eighty-eight percent were GLASS stage III. Freedom from CLTI was not significantly different between HePTFE and VEIN groups (75% vs. 84%, adjusted hazard ratio [aHR] 0.88, confidence interval [CI] 0.66-1.18, P = 0.401). Recurrence of CLTI was higher in the HePTFE group (42% vs.18% at 3 years; aHR 2.82, CI 1.59-5.00, P < 0.001). The VEIN group achieved higher rates of freedom from major amputation (87% vs.69% at 3 years; aHR 2.21, CI 1.31-3.75, P = 0.003) and AFS (59% vs. 37% at 3 years; aHR 1.39, CI 1.02-1.88, P = 0.036), but no significance in survival (aHR 1.10, CI 0.72-1.66, P = 0.667). Patency rates were inferior in the HePTFE group, with 2-year PP and SP rates of 52% vs. 74%, and 76% vs. 90%, respectively (PP: aHR 1.70, CI 1.11-2.59, P = 0.014; SP: aHR 2.51, CI 1.42-4.42, P = 0.001).

CONCLUSIONS

Infrapopliteal bypass with autologous vein graft is the gold standard to treat CLTI limbs. HePTFE graft should be regarded as an alternative for complex infrapopliteal revascularization when lacking an autologous vein conduct.

Short-Term Results of Varicose Vein Graft Used for Lower-Limb Bypass Surgery

Objective: Due to the potential of thrombus blockage and aneurysm rupture, saphenous veins with varicose veins are not advised for use as bypass grafts. However, if no other autologous vein is accessible for use as a conduit in lower-limb bypass; varicose vein transplants may be employed. Few reports have studied the clinical results of lower-limb bypass using varicose vein grafts. We therefore investigated whether or not acceptable patency rates of varicose vein graft for lower-limb bypass could be achieved. Methods: We performed lower-limb bypass using varicose vein graft on nine limbs from June 2017 to May 2020 and conducted a retrospective analysis of prospectively collected data. Results: Early graft failure following bypass surgery using a varicose vein transplant was not detected, and major complications, such as acute graft occlusion or aneurysm dilatation, were not noted throughout the follow-up period. The primary and secondary patency of varicose vein graft was 70.0% and 100% at 3 years, respectively. Conclusion: The incidence of major problems of the varicose vein transplants does not seem to be higher than with conventional saphenous vein grafts. If there are no other appropriate autologous veins, a varicose vein graft may be useful as a conduit for bypass surgery.

Treatment Outcomes between Bypass Surgery and Endovascular Therapy in Patients with Chronic Limb-Threatening Ischemia classified as Bypass-preferred category based on Global Vascular Guidelines

OBJECTIVE

To examine outcomes between bypass surgery and endovascular therapy (EVT) in patients with chronic limb-threatening ischemia (CLTI), classified as bypass-preferred according to the Global Vascular Guidelines (GVG).

METHODS

We retrospectively analyzed the multi-center data of patients who underwent infrainguinal revascularization for CLTI with Wound, Ischemia, and foot Infection (WIfI) Stage 3-4 and Global Limb Anatomical Staging System (GLASS) Stage III, which is classified as bypass-preferred category by the GVG between 2015 and 2020. The endpoints were limb salvage and wound healing.

RESULTS

We analyzed 301 patients and 339 limbs following 156 bypass surgery and 183 EVT. The 2-year limb salvage rates were 92.2% in the bypass surgery group and 76.3% in the EVT group, respectively (P < .01). The 1-year wound healing rates were 86.7% in the bypass surgery group and 67.8% in the EVT group (P < .01). Multivariate analysis shows decreased serum albumin level (P < .01), increased wound grade (P = .04), and EVT (P < .01) were risk factors for major amputation. Decreased serum albumin level (P < .01), increased wound grade (P < .01), GLASS infrapopliteal grade (P = .02), and inframalleolar (IM) P grade (P = .01), and EVT (P < .01) were risk factors for impaired wound healing. Subgroup analysis of limb salvage in patients after EVT, decreased serum albumin level (P < .01), increased wound grade (P = .03), increased IM P grade (P = .04), congestive heart failure (P < .01) were risk factors for major amputation. According to scoring by existence of these risk factors, 2-year limb salvage rates following EVT were 83.0% and 42.8% for the total score of 0-2 and of 3-4, respectively (P < .01).

CONCLUSIONS

Bypass surgery provides better limb salvage and wound healing in patients with WIfI Stage 3-4 and GLASS Stage III, which is classified as bypass-preferred category by the GVG. In patients after EVT, serum albumin level, wound grade, IM P grade, and congestive heart failure were related to major amputation. Although bypass surgery may be considered as initial revascularization procedure in patients classified as bypass-preferred category, in case that EVT has to be selected, relatively acceptable outcomes can be expected in patients with less these risk factors.

Impact of Tibial Bypass Conduit on Long-Term Amputation-Free Survival and Primary Patency in the Vascular Quality Initiative

BACKGROUND

Much research remains focused on tibial bypass conduit selection. We sought to describe long-term amputation-free survival (AFS) and primary patency (PP) of patients undergoing tibial bypass by conduit type and configuration across several permutations in the Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI).

METHODS

Patients in the VQI registry undergoing elective first-time femoral- or popliteal-to-tibial bypass for occlusive disease involving rest pain or tissue loss were identified. Prior ipsilateral infrainguinal bypass or concomitant procedures were excluded. Outcomes of interest included patient AFS at 22 months and PP at 1 year (defined as freedom from revision, thrombectomy, or graft occlusion).

RESULTS

A total of 4,192 bypasses were identified. The majority utilized Great Saphenous Vein (GSV) (76.2%), followed by polytetrafluoroethylene (PTFE) (10.6%), non-autologous biologic (NABC) (6.5%), composite (3.3%), arm vein (2.8%), and Small Saphenous Vein (SSV) (0.6%). Compared to all prosthetic and composite bypasses, vein grafts had the best AFS (76.4%, p<0.0001) and PP (68.1%, p=0.041). Of the single segment vein conduits, GSV bypasses had the best PP (69.1%) and arm vein the worst (60.2%). AFS and PP were similar between single segment GSV orientations. Single segment GSV bypasses exhibited better PP than multiple segment bypasses (69.1% vs 54.6%, p=0.0016). PP was significantly better for PTFE compared to NABC (68.4% vs 51.2%, p=0.0039). PP did not significantly differ between vein cuff (PWC) for prosthetic bypass compared to no vein cuff (PNC) (69.1% vs 59.7%, p=0.091). PP was not significantly different between single segment GSV and prosthetic grafts with vein cuff (69.1% vs 69.1%, p=0.51). There were no significant differences in AFS comparing arm vein, PWC, or composite grafts (67.2% vs 63.8% vs 59.3%, p=0.092), as well as in PP (60.2% vs 69.1% vs 54.8%, p=0.14).

CONCLUSIONS

Single-segment vein bypass was only marginally the most optimal conduit. Surprisingly, there may be more equipoise among conduit types, particularly in the absence of adequate GSV. Prosthetic grafts overall may not be as disadvantaged in the long term as initially thought, especially when compared to arm vein, as PWC did not significantly differ in primary patency. Similarly, a composite conduit may not impact long-term outcomes. These data suggest that conduit choice may not impact outcomes to the degree previously thought and that other factors may have a greater impact than presumed, especially in conduit limited situations.