Long-term outcomes of autologous vein bypass for repair of upper and lower extremity major arterial trauma.

OBJECTIVE: Autologous vein is the preferred bypass conduit for extremity arterial injuries owing to superior patency and low infection risk; however, long-term data on outcomes in civilians are limited. Our goal was to assess short- and long-term outcomes of autologous vein bypass for upper and lower extremity arterial trauma. METHODS: A retrospective review was performed of patients with major extremity arterial injuries (2001-2019) at a level I trauma center. Demographics, injury and intervention details, and outcomes were recorded. Primary outcomes were primary patency at 1 year and 3 years. Secondary outcomes were limb function at 6 months, major amputation, and mortality. Multivariable analysis determined risk factors for functional impairment. RESULTS: There were 107 extremity arterial injuries (31.8% upper and 68.2% lower) treated with autologous vein bypass. Mechanism was penetrating in 77% of cases, of which 79.3% were due to firearms. The most frequently injured vessels were the common and superficial femoral (38%), popliteal (30%), and brachial arteries (29%). For upper extremity trauma, concomitant nerve and orthopedic injuries were found in 15 (44.1%) and 11 (32.4%) cases, respectively. For lower extremities, concomitant nerve injuries were found in 10 (13.7%) cases, and orthopedic injuries in 31 (42.5%). Great saphenous vein was the conduit in 96% of cases. Immediate intraoperative bypass revision occurred in 9.3% of patients, most commonly for graft thrombosis. The in-hospital return to operating room rate was 15.9%, with graft thrombosis (47.1%) and wound infections (23.5%) being the most common reasons. The median follow-up was 3.6 years. Kaplan-Meier analysis showed 92% primary patency at 1 year and 90% at 3 years. At 6 months, 36.1% of patients had functional impairment. Of patients with functional impairment at 6 months, 62.9% had concomitant nerve and 60% concomitant orthopedic injuries. Of those with nerve injury, 91.7% had functional impairment, compared with 17.8% without nerve injury (P < .001). Of patients with orthopedic injuries, 51.2% had functional impairment, vs 25% of those without orthopedic injuries (P = .01). On multivariable analysis, concomitant nerve injury (odds ratio, 127.4; 95% confidence interval, 17-957; P <. 001) and immediate intraoperative revision (odds ratio, 11.03; 95% confidence interval, 1.27-95.55; P = .029) were associated with functional impairment. CONCLUSIONS: Autologous vein bypass for major extremity arterial trauma is durable; however, many patients have long-term limb dysfunction associated with concomitant nerve injury and immediate intraoperative bypass revision. These factors may allow clinicians to identify patients at higher risk for functional impairment, to outline patient expectations and direct rehabilitation efforts toward improving functional outcomes.

Longer Operative Time for Lower Extremity Bypass Surgery is Associated With Inferior Outcomes.

INTRODUCTION: This study aims to assess the association of operative time with the postoperative length of stay and unplanned return to the operating room in patients undergoing femoral to below knee popliteal bypasses, stratified by autologous vein graft or polytetrafluoroethylene (PTFE). MATERIALS AND METHODS: A retrospective analysis of vascular quality initiative database (2003-2021). The selected patients were grouped into the following: vein bypass (group I) and PTFE (group II) patients. Each group was further stratified by a median split of operative time (i.e., 210 min for autologous vein and 155 min for PTFE) to study the outcomes. The outcomes were assessed by univariate and multivariate approach. RESULTS: Of the 10,902 patients studied, 3570 (32.7%) were in the autologous vein group, while 7332 (67.3%) were in the PTFE group. Univariate analysis revealed autologous vein and PTFE graft recipients that had increased operative times were associated with a longer mean postoperative length of stay and a higher incidence of all-cause return to the operating room. In PTFE group, patients with prolonged operative times were also found to be associated with higher incidence of major amputation, surgical site infection, and cardiovascular events, along with loss of primary patency within a year. CONCLUSIONS: For patients undergoing femoral to below knee popliteal bypasses using an autologous vein or PTFE, longer operative times were associated with inferior outcomes. Mortality was not found to be associated with prolonged operative time.

Alternative Conduits for Lower Extremity Bypass.

While single-segment great saphenous vein (GSV) remains the gold-standard conduit for infrainguinal bypass, several alternative options are available for use when GSV is absent in patients with chronic limb threatening ischemia requiring infrainguinal revascularization including alternative autologous vein, prosthetic conduits, and cryopreserved vein grafts.

Autologous Alternative Vein Grafts for Infrainguinal Bypass in the Absence of Single-Segment Great Saphenous Vein: A Single-Center Study.

BACKGROUND: Alternative autologous veins can be used as a conduit when adequate great saphenous vein is unavailable. We analyzed the results of our infrainguinal bypasses after adopting upper extremity veins in our practice. METHODS: This is a single-center observational study involving all patients whose infrainguinal bypass involved the use of upper extremity veins between April 2019, when we began using arm veins, and February 2023. RESULTS: During the study period, 49 bypasses were done in 48 patients; mean age 68.1 ± 9.8; men 32 (66.7%); body mass index 28.0 ± 4.8; indications for surgery: chronic limb threatening ischemia 41 (83.7%); acute limb ischemia 3 (6.1%); complications of previous prosthetic 3 (6.1%), or autologous 2 (4.1%) bypass grafts. Vein splicing was used in 43 (87.8%) bypasses with 3-segment grafts being the most common (26; 53.1%). There were 24 (49.0%) femorotibial, 11 (22.4%) femoropopliteal, 9 (18.4%) femoropedal, and 5 (10.2%) extension jump bypass procedures. Eighteen (36.7%) operations were redo surgeries. Twenty-one (42.9%) bypasses were formed using only arm veins. The median follow-up was 12.9 months (4.5-24.2). Two bypasses occluded during the first 30 postoperative days (2/49; 4.1%). Overall 30-day, 1-year, and 2-year primary patency rates were 93.7% ± 3.5%, 84.8% ± 5.9%, and 80.6% ± 6.9%, and secondary patency (SP) rates were 95.8% ± 2.9%, 89.2% ± 5.3%, and 89.2% ± 5.3%. One-segment grafts had better patencies than 2-, 3-, and 4-segment grafts (1-year SP 100% ± 0% vs 87.6% ± 6.0%). Two-year amputation-free survival was 86.8% ± 6.5%; 2-year overall survival was 88.2% ± 6.6%. CONCLUSIONS: Integration of arm vein grafts in infrainguinal bypass practice can be done safely with low incidences of perioperative graft failure. One-segment grafts had better patencies than spliced vein grafts. The achieved early patency and amputation-free survival rates strongly encourage their use. In the absence of a single-segment great saphenous vein, upper extremity vein grafts should be the preferred conduit choice.

Treatment of Patients With Electrical Injury by Using Modified Forearm Venous Flap: Retrospective Case Series Study.

OBJECTIVE: Severe hand electrical injuries often occur in functional areas such as joints; the repair requires attention to both appearance and function due to the visibility of the hand. This study aimed to present the clinical experience of successfully repairing hand electrical injuries using improved forearm venous flaps. METHODS: From 2020 to 2022, 15 cases of severe hand electrical injuries were diagnosed, including 10 males and 5 females. Among them, 6 cases were repaired in the first web space, 4 in the thumb, 3 in the index finger, 2 in the middle finger, 2 in the ring finger, and 2 in the little finger. The size of venous flaps ranged from 2.0 cm × 1.8 cm to 12 cm × 4.0 cm. All patients underwent repair using improved forearm venous flaps. The follow-up period ranged from 5 to 8 months. RESULTS: All flaps survived without serious complications. All patients were satisfied with the postoperative aesthetics and function of their hands. CONCLUSION: The improved forearm venous flap is a simple and reliable method for repairing hand electrical injuries.

Comparisons of Impact of Vein Grafting with Different Indications on Outcomes of Reconstruction with Free Flaps.

BACKGROUND: Prior studies have shown an increased risk of complications and flap loss with the use of vein grafts in microsurgery. We hypothesize that indication for use of a vein graft can affect flap complications and loss rates. METHODS: We performed a retrospective review of all patients at our institution from 2010 to 2020 who underwent free flap reconstruction and required use of a vein graft. Indications for vein grafting included: salvage of flap during primary operation after microvascular compromise, augmentation of flow during primary operation, lengthening of the flap pedicle during the primary operation, and salvage of the flap during a secondary salvage operation after microvascular compromise. RESULTS: A total of 79 patients met the study inclusion criteria. There were significant differences among the vein graft indication groups and the following: area of reconstruction (p = 0.002), vein graft length (p = 0.018), vessels grafted (p = 0.001), vein graft donor site (p = 0.011), and total flap loss (p = 0.047). Of the four indications for vein grafting, salvage of the flap during secondary salvage operation after microvascular compromise had the highest rate of total flap loss (26.7%). There were no significant associations between other flap complications and vein graft indications. CONCLUSION: Vein graft use in the primary reconstructive setting is efficacious, with low risk of thrombosis. Use in secondary procedures, however, is associated with higher rates of total flap loss, likely due to the thrombotic process, which was initiated prior to the use of the graft resulting in the salvage procedure and not secondary to the graft itself.

Prefabrication-a Vascularized Skin Flap Using an Arteriovenous LoopPrefabricated Flap With Arteriovenous Loop: An Experimental Study in Minipigs.

BACKGROUND: Arteriovenous loops have a high potency to induce angiogenesis and are promising to solve the problem of scarce implanted pedicle sources and insufficient neovascularization in flap prefabrication. But there is a lack of large animal experiments to support their clinical application. Therefore, we aimed to explore the feasibility of prefabricating large flaps based on arteriovenous loops in pigs. METHODS: Five minipigs were used. In the experimental group, a 10-cm-long ear vein graft was microanastomosed with the saphenous artery and vein to form an arteriovenous loop and implanted under the medial thigh flap. A month later, a 10×10 cm prefabricated flap pedicled with the arteriovenous loop was elevated and sutured in situ. In the control group, a 10×10 cm flap with no vascular pedicle was elevated completely and sutured in situ in the same position. The patency of the arteriovenous loop was evaluated by angiography 30 days after implantation, and the viability of flaps was assessed by macroscopic analysis 10 days after elevation. Three animals received arteriovenous loop flaps unilaterally and no-pedicle flaps unilaterally. Two animals received arteriovenous loop flaps bilaterally. RESULTS: In the experimental group, no thrombi were exhibited in any arteriovenous loop. All 7 prefabricated flaps survived uneventfully. In the control group, 3 flaps were completely necrotic. CONCLUSION: The arteriovenous loops with long interpositional venous grafts can be used as vascular pedicles to prefabricated large area and well-vascularized flaps. This approach can greatly expand the application of flap prefabrication.

Comparison of Prosthetic and Vein Bypass with Nitinol Stents in Long Femoropopliteal Lesions.

BACKGROUND: Guidelines for the treatment of long femoropopliteal lesions are not based on a high level of evidence and recent randomized controlled trials (RCTs) challenge vein bypass (VBP) as the recommended therapy. This study compared prosthetic (PTFE) bypass, VBP and angioplasty with nitinol stents in long femoropopliteal lesions. METHODS: Pooled data from a RCT and a retrospective database with the same inclusion criteria were analyzed with primary and secondary patency as well as freedom from target lesion revascularization (TLR) as primary endpoints. RESULTS: Between 2016 and 2018 a total of 172 lesions were treated in three groups (PTFE: n = 62, VBP: n = 55, stent: n = 55). Clinical and lesion characteristics were similar with mean lesion lengths between 260 and 279mm. Technical success rate in the stent group was 87%. There were no significant differences between the groups in patency rates, freedom from TLR, limb salvage and survival during 2-year follow-up. The primary patency rates for the PTFE, VBP and stent groups were 50%, 56% and 60% at 2 years. The PTFE group had significantly less complications compared to the other groups and a shorter hospital-stay compared to the VBP group. Clinical improvement was significantly better in the PTFE and VBP group compared to the stent group. CONCLUSIONS: The 2-year results indicate that the role of VBP as the recommended therapy for long femoropopliteal lesions may not be unchallenged due to the similar results in all three groups. Further RCTs are needed to determine the best revascularization modality for long femoropopliteal lesions.

Distal revascularization and interval ligation for dialysis access-related ischemia is best performed using arm vein conduit.

OBJECTIVE: Distal revascularization and interval ligation (DRIL) is an effective approach to the management of hemodialysis access-related ischemia that offers both symptom relief and access salvage. The great saphenous vein (GSV) has been the most commonly used conduit. However, the use of an ipsilateral arm vein will allow for performance of the operation with the patient under regional anesthesia and might result in lower harvest site morbidity than the GSV. We sought to determine the suitability of DRIL using an arm vein compared with a GSV conduit. METHODS: All patients who had undergone DRIL from 2008 to 2019 were retrospectively identified in the electronic medical records. The characteristics and outcomes of those with an arm vein vs a GSV conduit were compared using the Wilcoxon log-rank and χ2 tests. Access patency was examined using Kaplan-Meier methods, with censoring at lost to follow-up or death. RESULTS: A total of 66 patients who had undergone DRIL for hand ischemia were included in the present study. An arm vein conduit was used in 40 patients (median age, 65 years; 25% male) and a GSV conduit in 26 patients (median age, 58 years; 19% male). No significant differences in comorbidities were found between the two groups, with the exception of diabetes mellitus (arm vein group, 78%; GSV group, 50% GSV; P = .02). No difference in the ischemia stage at presentation was present between the groups, with most patients presenting with stage 3 ischemia. Also, no differences in patency of hemodialysis access after DRIL between the two groups were found (P = .96). At 12 and 24 months after DRIL, 86.9% (95% confidence interval [CI], 68.3%-94.9%) and 82.0% (95% CI, 61.3%-92.3%) of patients with an arm vein conduit had access patency compared with 93.8% (95% CI, 63.2%-99.1%) and 76.9% (95% CI, 43.0%-92.2%) of those with a GSV conduit, respectively. All but one patient had symptom resolution. The incidence of wound complications was significantly greater in the GSV group than in the arm vein group (46% vs 11%; P = .003). DRIL bypass had remained patent in all but one patient in each group, with a median follow-up of 18 months (range, 1-112 months) in the arm vein conduit group and 15 months (range, 0.25-105 months) in the GSV conduit group. CONCLUSIONS: DRIL procedures using an arm vein have advantages over those performed with the GSV. In our series, symptom resolution and access salvage were similar but distinctly fewer wound complications had occurred in the arm vein group. Additionally, the use of an arm vein conduit avoids the need for general anesthesia. If an ipsilateral arm vein is available, it should be the conduit of choice when performing DRIL.

Long Term Outcomes of Endovascular Therapy for Failing Distal Bypass Vein Grafts.

OBJECTIVE: Although distal bypass using vein has been established with acceptable outcomes for chronic limb threatening ischaemia (CLTI), the major issue affecting long term outcomes is vein graft disease. This study aimed to analyse the peri-procedural results and long term outcomes of endovascular therapy (EVT) for failing vein grafts after distal bypass. METHODS: A retrospective analysis of 113 failing vein grafts (94 patients, 113 limbs) after distal bypass between 2009 and 2019 at the study hospital. RESULTS: The mean age was 74 ± 9 years and 72% of the patients were men. Of the 113 grafts, 54 grafts (48%) were detected in asymptomatic patients, 41 grafts (36%) in patients with recurrent ulcer or gangrene, and 18 grafts (16%) in patients with rest pain. The failing grafts were treated by low pressure long inflation balloon angioplasty with a mean balloon size of 3.0 ± 0.8 mm. The mean procedural time was 60 ± 29 min and procedural success was 98% (111 grafts). During the mean follow up period of 34 months, EVT was performed a median frequency of two times (range 1-11 times). The primary and assisted primary patency of the EVT revised grafts were 41% and 80% at one year, 34% and 68% at three years, 31% and 58% at five years, respectively. Of 41 limbs with recurrent ulcer or gangrene, the wound healed in 34 limbs (85%). The complete healing rate was 71% at three months and 84% at 12 months. Eight patients required major amputation, and the freedom from major amputation rate was 96% at one year and 80% at five years. CONCLUSION: Long term outcomes including patency, wound healing rate, and amputation free survival after EVT for failing vein grafts were acceptable. EVT could be a viable alternative to surgical revascularisation in patients with a failing distal bypass graft for CLTI.

Role of Bypass with Preoperatively Diagnosed Small Caliber Veins in Chronic Limb-Threatening Ischemia.

BACKGROUND: In chronic limb-threatening ischemia (CLTI), although recent studies suggested that limbs classified as a higher Wound, Ischemia, foot Infection (WIfI) stage would benefit more from bypass surgery than endovascular therapy (EVT), graft unavailability is a major limitation for bypass. However, such graft unavailability is not clearly defined. This study aimed to assess whether bypass with veins judged as small by preoperative ultrasound is acceptable to achieve wound healing. METHODS: Ninety-five limbs classified as WIfI stage 3/4 that underwent infrainguinal bypass with veins were enrolled and divided into two groups based on the preoperative inner diameter of veins. Those with a diameter <2.5 mm were classified as small caliber grafts (SMGs, n=28) and those with a diameter ≥2.5 mm as sufficient caliber grafts (SUGs, n=67), and wound-related outcomes were evaluated. Wound healing rate (WHR) was analyzed in all cohort, and wound recurrence-free rate (WRF) and wound recurrence-free amputation-free survival rate (WRAFS) were calculated for limbs that achieved wound healing. A propensity score matched analysis was also performed to minimize the background difference, and 21 matched pairs were included for the analysis. RESULTS: Although the primary patency rate was significantly worse in SMGs (1-year patency, Crude model: 82.1% in SUGs and 51.0% in SMGs, P=0.0003; matched model: 77.7% in SUGs and 41.6% in SMGs, P = 0.005), the secondary patency rate was maintained in the equivalent level (1-year patency, Crude model: 81.8% in SUGs and 83.1% in SMGs, P=0.26; matched model: 77.7% in SUGs and 78.4% in SMGs, P = 0.24). One-year WHR was equivalent between the groups in both crude and matched models (Crude model: 87.0% in SUGs and 83.8% in SMGs, P=0.13; matched model: 66.3% in SUGs and 61.4% in SMGs, P = 0.65). One-year WRF and WRAFS were also equivalent (Crude model: WRF, 95.9% in SUGs and 100% in SMGs, P = 0.71; WRAFS, 87.2% in SUGs and 88.0% in SMGs, P = 0.78. Matched model: WRF, 100% in SUGs and 100% in SMGs, P = 0.85; WRAFS, 92.9% in SUGs and 78.6% in SMGs, P = 0.38). CONCLUSIONS: Although bypass with small caliber veins showed an inferior primary patency rate, WHR and WRF were equally good if grafts are maintained patent. Bypass with small caliber vein grafts would be an important option to achieve wound healing.

Comparison of Outcomes for Open Popliteal Artery Aneurysm Repair Using Vein and Prosthetic Conduits.

BACKGROUND: Autologous vein is considered the preferred conduit for lower extremity bypass. There is, however, limited literature regarding conduit choice for open popliteal artery aneurysm (PAA) repair. We sought to compare outcomes of PAA repair using vein versus prosthetic conduits. METHODS: The Vascular Quality Initiative database (2003-2019) was queried for patients with PAAs undergoing elective conventional revascularization originating from the superficial femoral and popliteal arteries. Conduits were categorized as vein or prosthetic. Primary outcomes were primary graft patency, freedom from major adverse limb event (MALE) and MALE-free survival at 2-years. Kaplan-Meier method with log-rank tests was used for estimation and comparison of patency. RESULTS: A total of 1,146 limbs in 1,065 patients underwent elective open revascularization for PAA. Vein was used in 921 limbs (80%), and prosthetic in 225 (20%). Patients in the prosthetic cohort had a shorter procedure time, were older, and had a higher prevalence of COPD. Postoperatively, prosthetic patients were more likely to be started and maintained on anticoagulation without increased incidence of hematoma. There was no significant difference in the rate of surgical site infection (2% vs. 2%; P = 0.946). There was an increased tendency toward more symptomatic patients in the vein cohort although not statistically significant (49% vein vs. 41% prosthetic; P = 0.096). On a mean follow-up of 13 ± 5 months, the incidence of MALE and MALE-free survival were comparable between the two groups. The 2-year primary and secondary patency rates were similar, 87% and 96% in the vein, and 91% and 95% in the prosthetic groups, respectively. At multivariable analysis, outflow bypass targets to the infrapopliteal arteries (HR 2.05; 95% confidence interval (CI), 1.16-3.65; P = 0.014) and symptomatic aneurysm (HR 1.81; 95% CI, 1.04-3.15; P = 0.037) were independently associated with loss of primary patency. Conduit type did not make a difference in MALE-free survival, or primary graft patency at 2-years. CONCLUSION: Our study demonstrates that conventional open PAA repair with prosthetic conduit yields results comparable to those with vein conduit with regard to primary and secondary patency and MALEs at 2-years for targets to the popliteal artery. However, when the distal target was infrapopliteal, worse outcomes were observed with prosthetic conduit. Our results suggest that vein conduit should be preferentially used for infrapopliteal targets, while prosthetic conduit confers comparable outcomes in a subset of patients who do not have suitable autologous vein conduits.

Novel Technique for Latero-anterior Approach to the Terminal Peroneal Artery for Bypass Surgery without Fibular Resection.

The peroneal artery (PeA) is often a vital target vessel for lower limb revascularization. Exploring the distal PeA can be challenging via the conventional approaches. We present a new, minimally invasive technique for a latero-anterior approach to the terminal PeA without fibular resection as either a target outflow vessel for open bypass revascularization surgery or, as in this report, the inflow for a crural-pedal bypass in a challenging case of critical limb-threatening ischemia.

Contemporary Outcomes of Peripheral Bypass Compared with Amputation in Octogenarians.

BACKGROUND: Chronic limb threatening ischemia in octogenarians presents unique treatment challenges in patients with multiple comorbidities and variable functional status. Endovascular interventions offer a better risk profile; however, this is not always a feasible option for anatomic or disease-specific reasons. This study compares outcomes of peripheral bypass versus amputation in octogenarians. METHODS: The American College of Surgeon's National Surgical Quality Improvement Program database was queried from 2013 to 2016 for patients >80 years undergoing femoral-popliteal bypass (FPB), femoral-tibial bypass, or popliteal-tibial bypass with vein or prosthetic graft versus above-knee amputation (AKA) or below-knee amputation. Patients presenting with systemic inflammatory response syndrome, sepsis, septic shock, or a leukocytosis >11,000 were excluded. Patient demographics, risk factors, and 30-day unadjusted outcomes were analyzed. Multivariate regression analysis was then performed to compare risk adjusted 30-day morbidity and mortality. RESULTS: The bypass group contained 2226 patients compared with 1253 patients in the amputation group. AKA represented 59.9% of the amputation group. The largest portion of bypasses were FPBs at 58.6%. Total preoperative functional dependence was 1.3% for bypass versus 18.2% for amputation (P-value, <0.01). Risk factors for amputation over bypass included age, minority race, American Society of Anesthesiologists class IV-V, diabetes, congestive heart failure, dialysis, preoperative open wound, facility of origin, and functional dependence. Unadjusted 30-day mortality was 3.6% for bypasses and 7.7% for amputations (P-value, <0.01), with an in-hospital mortality of 2.0% vs. 3.2% and a mortality after discharge of 1.6% vs. 4.5%, respectively (P-value <0.01). Unadjusted morbidity was not significantly different between the 2 groups (18.7% bypass vs. 17.8% amputation, P-value, 0.52). After multivariate risk adjustment, there was no statistically significant difference in mortality or morbidity between the groups. CONCLUSIONS: Contemporary risk-adjusted 30-day morbidity and mortality for bypass versus amputation in octogenarians show no significant difference. These data demonstrate that aggressive surgical limb salvage can be safe in well-selected patients in this age group.

Predictive Model for Postoperative Ambulatory Function after Lower Extremity Bypass in Chronic Limb-Threatening Ischemia.

BACKGROUND: In chronic limb-threatening ischemia, maintenance or recovery of ambulatory function is an important goal of treatment. This study aimed to develop a predictive model for ambulatory ability 1 year after bypass based on preoperative risk factors, including the Wound, Ischemia, and foot Infection (WIfI) classification. METHODS: We analyzed 146 patients with chronic limb-threatening ischemia (154 limbs) who underwent bypass to below the knee arteries. The patients were classified into 2 groups based on ambulatory status 1 year postoperatively: postoperative ambulation (99 patients, 104 limbs) and postoperative nonambulation (47 patients, 50 limbs). Various factors associated with postoperative ambulation were analyzed and a predictive model of postoperative ambulation was developed. RESULTS: Multivariate logistic regression analysis detected preoperative nonambulatory status, functional nonindependence in daily living, older age, WIfI wound grade 3, chronic obstructive pulmonary disease, and hemodialysis as independent risk factors for postoperative nonambulation. The predictive scoring model (scores ranging from -5.0 to 4.4) comprising these risk factors discriminated the postoperative ambulatory status well: the probabilities of postoperative ambulatory ability were ≥85% in those with a score ≤-2, 50% in those with a score of zero, and ≤15% in those with a score ≥2. The area under the receiver operating characteristic curve was 0.898, indicating good performance of the model. CONCLUSIONS: Preoperative nonambulatory status, functional nonindependence, advanced age, high WIfI wound grade, chronic obstructive pulmonary disease, and hemodialysis were important predictors of postoperative nonambulatory status. The predictive model will help us identify patients who will benefit from bypass surgery.

Pseudoaneurysm Development after Drug-Eluting Balloon (DEB) Angioplasty of a Venous Femoropopliteal Bypass Graft.

Endovascular recanalization of occluded venous femoropopliteal bypass grafts is widely used because of easy access. This case report describes pseudoaneurysm developing 4 weeks after endovascular recanalization of an occluded in situ venous femoropopliteal graft. The patient was treated for a popliteal aneurysm with a venous femoropopliteal bypass graft, which subsequently occluded. Four weeks after DEB PTA, the occluded graft developed 3 pseudoaneurysms. Impaired vessel wall healing after intraluminal paclitaxel administration could have contributed to this. This case adds a perspective to the choice of treatment of occluded venous femoropopliteal bypass grafts.

A Comparison of Outcomes Based on Vessel Type (Native Artery vs. Bypass Graft) and Artery Location (Below-Knee Artery vs. Non-Below-Knee Artery) Using a Combination of Multiple Endovascular Techniques for Acute Lower Limb Ischemia.

BACKGROUND: To evaluate outcomes of endovascular treatment (EVT) using a combination of multiple endovascular techniques for acute lower limb ischemia (ALLI) and to compare outcomes based on vessel type and artery location. METHODS: A total of 95 consecutive patients with ALLI (mean age, 72.0 years; 65 males; 104 lower limbs) who received emergency EVT using a combination of multiple endovascular techniques including thrombolysis, aspiration thrombectomy, stenting, and balloon angioplasty with or without surgical thromboembolectomy, between January 2005 and December 2017 were included. Vessel type was classified into native artery occlusion (native occlusion) and bypass graft occlusion (graft occlusion), including prosthetic and vein graft. Additionally, native arteries were categorized into below-knee occlusion and non-below-knee occlusion. Technical success, perioperative death (POD), ALLI-related death, amputation, amputation-free survival (AFS), and complications were compared according to vessel type (native occlusion vs. graft occlusion) and artery location (below-knee occlusion vs. non-below-knee occlusion). RESULTS: Of all patients with ALLI, 16.8% underwent a single endovascular technique, whereas 83.2% underwent a combination of multiple endovascular techniques. The technicalsuccess, POD, and ALLI-related death rates in the total number of patients were 94.7%, 11.6%, and 4.2%, respectively. A total of 67 patients (75 limbs) and 28 patients (29 limbs) were classified as having native occlusion and graft occlusion (prosthetic, 24 limbs; vein, 5 limbs), respectively. No significant differences in technical success (native occlusion: 92.5% vs. graft occlusion: 100%), POD (14.9% vs. 3.6%), and ALLI-related death (6.0% vs. 0%) were noted between native occlusion and graft occlusion. However, the 30-day AFS rate of native occlusion was significantly lower than that of graft occlusion (75.2% vs. 96.3%, P=0.01). The amputation rate (P=0.03) and AFS rate (P=0.03) of below-knee occlusion were significantly worse for below-knee occlusion patients than for non-below-knee occlusion patients. CONCLUSIONS: EVT using multiple endovascular techniques for ALLI is effective and safe. A combination of multiple endovascular techniques is crucial for successful treatment. However, native occlusion may have a lower AFS rate than graft occlusion, and below-knee occlusion may have a higher risk of amputation than non-below-knee occlusion.

Heterogeneous and dynamic lumen remodeling of the entire infrainguinal vein bypass grafts in patients.

OBJECTIVE: To examine the regional variation and temporal change in lumen size along the entire autogenous vein bypass graft used for treating arterial occlusive disease in lower extremity and to explore the factors associated with graft expansive or constrictive remodeling. METHODS: Patients were prospectively scanned using contrast-enhanced computed tomography at 1 week and 1, 6, and 12 months postoperatively to obtain lumen cross-sectional areas at 1-mm intervals along the entire grafts. Graft lumen remodeling characteristics and the associated demographic and clinical factors were examined. RESULTS: Fifty-six patients with at least two consecutive computed tomography scans were analyzed. Patients with a composite or longer graft, or with diabetes, had a larger lumen cross-sectional area variation along the graft. The mean lumen cross-sectional areas of all the grafts demonstrated no significant changes through 12 months. However, individually, graft remodeling was time dependent and there was a more dramatic change in lumen cross-sectional area within the first postoperative month. At 12 months, a near equal distribution between expansive and constrictive grafts existed. A negative relation between the initial lumen diameters and the subsequent lumen diameter changes was observed. Eleven grafts failed within 12 months; failed and patent grafts had similar mean lumen cross-sectional areas at all four time points, but failed grafts had a larger maximal local cross-sectional area reduction from 1 week to 1 month (58.0 ± 6.7% vs 38.1 ± 3.1%, mean ± standard error of the mean, failed vs patent, P = .004). Black patients had a smaller mean lumen cross-sectional area than white patients at all four time points and also had a higher early percent mean area reduction (-20.5 ± 6.3% vs -1.0 ± 3.7%, black vs white, P = .018). Cilostazol use was associated with early expansive graft remodeling. CONCLUSIONS: Vein grafts remodel heterogeneously and dynamically. Remodeling is associated with initial graft lumen size, race, and cilostazol use. It is found that remodeling that produces some critical minimum area or maximal percent reduction during the first postoperative month may predispose to vein graft failure. These findings offer insight into further investigation to examine the underlying mechanisms and opportunities to improve graft remodeling and durability.

Vein Source Influences Neointimal Response in Rat Vein-to-Artery Grafts.

BACKGROUND: Vein graft stenosis is a major complication of coronary artery bypass surgery and peripheral arterial bypass procedures. Experimental models of this clinical complication have used in vivo grafting procedures, relying on the relatively modest neointimal thickening in these models as a surrogate for clinical graft stenosis without regard to the donor site origin of the vein graft. MATERIALS AND METHODS: In a standard rat model of vein grafting, three different donor sites were used to supply veins used as interpositional grafts to the femoral artery: the superficial inferior epigastric vein, the common femoral vein, and the posterior facial vein (distal branch of the jugular vein). Grafts were harvested as 4 wk and histomorphometrically evaluated for the extent of neointimal formation and lumen narrowing. RESULTS: The posterior facial vein showed significantly thicker neointima and a greater extent of lumen narrowing than the other two graft sources, despite having a similar diameter to the femoral vein and nearly twice the initial diameter of the epigastric vein. CONCLUSIONS: The source of donor graft material can greatly influence the extent of neointimal response after interpositional vein grafting to arterial flow. These findings support use of the posterior facial vein graft over other more standard donor vein grafts in research directed at understanding the causes and prevention of vein graft stenosis.

Clinical Outcomes Following Lower Extremity Vein Bypass for Chronic Limb Threatening Ischaemia (CLTI) at the University of Colombo, Sri Lanka.

OBJECTIVE: Although high quality epidemiological data are lacking, the global increase in chronic limb threatening ischaemia may be disproportionately affecting low and LMICs. All available data for outcomes from bypass for limb salvage are from high income countries, with none from LMIC settings where the challenge is greatest. This study aimed to assess the clinical outcomes following vein lower extremity bypass for chronic limb threatening ischaemia at the University of Colombo, Sri Lanka, and to compare patients and outcomes with those described in the Society for Vascular Surgery (SVS) Objective Performance Goals (OPG) and United States National Surgical Quality Improvement Program (NSQIP). METHODS: Consecutive patients (n = 367) undergoing SVS-OPG eligible lower extremity bypass between 2015 and 2017 were studied. Thirty day major adverse cardiovascular events (MACE), major adverse limb events (MALE), deaths, and amputations are reported, along with one year overall survival, limb salvage, and amputation free survival. RESULTS: Patients at University of Colombo had more diabetes mellitus (80% vs. SVS 57% vs. NSQIP 50%, p < .001) and tissue loss (100% vs. SVS 74% vs. NSQIP 59%, p < .001). The 30 day MALE was 7.6%, which is not a statistically significant difference from the SVS (6.1%) or NSQIP (9%). The 30 day MACE was 8.2%, statistically significantly higher than NSQIP (4.2%, p < .001) but not SVS (6.2%, p = .20). At 12 months, the overall survival (82%) was within the OPG threshold, but limb salvage (81.8%) and amputation free survival (64.5%) were just outside. CONCLUSION: Outcomes following vein bypass for ischaemic necrosis at the University of Colombo, Sri Lanka, are acceptable and similar to those reported from high income countries despite greater limb threat severity and resource limitations. Further real world data from similar settings on outcomes following revascularisation are required. These data suggest that a vein bypass first strategy for advanced ischaemic necrosis is feasible and effective even in resource limited settings.