Perioperative outcomes of infrainguinal bypass surgery in patients with and without prior revascularization

A Meta-Analysis to Derive Population-Based Quality Benchmarks of the Incidence of Surgical Site Infection after Lower Limb Revascularization Surgery

BACKGROUND

The reported incidence of surgical site infection (SSI) after lower limb revascularization surgery varies. We conducted a systematic review and meta-analysis of population-based studies reporting the incidence of SSI in adults who underwent these surgeries in high-income countries to derive SSI quality benchmarks.

METHODS

We searched MEDLINE, EMBASE, CENTRAL, and Evidence-Based Medicine Reviews (inception-to-April 28th, 2022) for population-based studies estimating the cumulative incidence of SSI among adults who underwent lower limb revascularization surgery for peripheral artery disease (PAD) in high-income countries. Two investigators independently screened abstracts and full-text articles, extracted data, and assessed risks of bias. We used random-effects models to pool data and GRADE to assess certainty.

RESULTS

Among 6,258 citations, we included 53 studies (n = 757,726 patients); 8 of which (n = 435,769 patients) reported nonoverlapping data that were meta-analyzed. The pooled cumulative incidence of any SSI was 6.0 in 100 patients [95% confidence interval (CI) = 4.3-8.0 in 100 patients; n = 8 studies; n = 435,769 patients; moderate certainty]. The cumulative incidence of Szilagyi grade I (cellulitis), grade II (subcutaneous tissue), and grade III (prosthetic graft) SSI was 6.5 in 100 patients (95% CI = 4.3-8.6 in 100 patients; n = 2 studies; n = 39,645 patients; low certainty), 2.1 in 100 patients (95% CI = 2.0-2.3 in 100 patients; n = 2 studies; low certainty), and 0.4 in 100 patients (95% CI = 0.4-0.4 in 100 patients; n = 1 study; n = 333,275 patients; low certainty), respectively. The pooled cumulative incidence of any early (in-hospital/≤30-days) and late (>30-days) SSI was 6.2 in 100 patients (95% CI = 4.4-8.0 in 100 patients; n = 7 studies; n = 431,273 patients; moderate certainty) and 3.7 in 100 patients (95% CI = 2.2-5.2 in 100 patients; n = 2 studies; n = 10,565 patients; low certainty), respectively.

CONCLUSIONS

This systematic review derived population-based benchmarks of the incidence of any SSI; Szilagyi I, II, and III SSI; and early and late SSI after lower limb revascularization surgery. These may be used by practicing surgeons and healthcare leaders/administrators to guide quality improvement efforts in the United States and perhaps other countries.

Descriptive Analysis of Amputation-Free Survival After First Time Infra-Inguinal Bypass Occlusion

INTRODUCTION

Occlusion after infra-inguinal bypass surgery for peripheral artery disease is a major complication with potentially devastating consequences. In this descriptive analysis, we sought to describe the natural history and explore factors associated with long-term major amputation-free survival following occlusion of a first-time infra-inguinal bypass.

METHODS

Using a prospective database from a tertiary care vascular center, we conducted a retrospective cohort study of all patients with peripheral artery disease who underwent a first-time infra-inguinal bypass and subsequently suffered a graft occlusion (1997-2021). The primary outcome was longitudinal rate of major amputation-free survival after bypass occlusion. Cox proportional hazard models were used to generate hazard ratios (HRs) and 95% confidence intervals (CIs) to explore predictors of outcomes.

RESULTS

Of the 1318 first-time infra-inguinal bypass surgeries performed over the study period, 255 bypasses occluded and were included in our analysis. Mean age was 66.7 (12.6) years, 40.4% were female, and indication for index bypass was chronic limb threatening ischemia (CLTI) in 89.8% (n = 229). 48.2% (n = 123) of index bypass conduits used great saphenous vein, 29.0% (n = 74) prosthetic graft, and 22.8% (n = 58) an alternative conduit. Median (interquartile range) time to bypass occlusion was 6.8 (2.3-19.0) months, and patients were followed for median of 4.3 (1.7-8.1) years after bypass occlusion. Following occlusion, 38.04% underwent no revascularization, 32.94% graft salvage procedure, 25.1% new bypass, and 3.92% native artery recanalization. Major amputation-free survival following occlusion was 56.9% (50.6%-62.8%) at 1 y, 37.1% (31%-43.3%) at 5 y, and 17.2% (11.9%-23.2%) at 10 y. In multivariable analysis, factors associated with lower amputation-free survival were older age, female sex, advanced cardiorenal comorbidities, CLTI at index procedure, CLTI at time of occlusion, and distal index bypass outflow. Initial treatment after occlusion with both a new surgical bypass (HR 0.44, CI: 0.29-0.67) or a graft salvage procedure (HR 0.56, CI: 0.38-0.82) showed improved amputation-free survival. One-year rate of major amputation or death were 59.8% (50.0%-69.6%) for those who underwent no revascularization, 37.9% (28.7%-49.0%) for graft salvage, and 26.7% (17.6%-39.5%) for new bypass.

CONCLUSIONS

Long-term major amputation-free survival is low after occlusion of a first-time infra-inguinal bypass. While several nonmodifiable risk factors were associated with lower amputation-free survival, treatment after graft occlusion with either a new bypass or a graft salvage procedure may improve longitudinal outcomes.

Risk Factors for Surgical Site Infection after Lower Limb Revascularisation Surgery: a Systematic Review and Meta-Analysis of Prognostic Studies

OBJECTIVE

To systematically review and meta-analyse adjusted risk factors for surgical site infection (SSI) after lower limb revascularisation surgery.

DATA SOURCES

MEDLINE, Embase, Evidence Based Medicine Reviews, and the Cochrane Central Register of Controlled Trials (inception to 28 April 2022).

REVIEW METHODS

Systematic review and meta-analysis conducted according to PRISMA guidelines. After protocol registration, databases were searched. Studies reporting adjusted risk factors for SSI in adults who underwent lower limb revascularisation surgery for peripheral artery disease were included. Adjusted odds ratios (ORs) were pooled using random effects models. GRADE was used to assess certainty.

RESULTS

Among 6 377 citations identified, 50 studies (n = 271 125 patients) were included. The cumulative incidence of SSI was 12 (95% confidence interval [CI] 10 - 13) per 100 patients. Studies reported 139 potential SSI risk factors adjusted for a median of 12 (range 1 - 69) potential confounding factors. Risk factors that increased the pooled adjusted odds of SSI included: female sex (pooled OR 1.41, 95% CI 1.20 - 1.64; high certainty); dependent functional status (pooled OR 1.18, 95% CI 1.03 - 1.35; low certainty); being overweight (pooled OR 1.82, 95% CI 1.29 - 2.56; moderate certainty), obese (pooled OR 2.20, 95% CI 1.44 - 3.36; high certainty), or morbidly obese (pooled OR 1.65, 95% CI 1.08 - 2.52; moderate certainty); chronic obstructive pulmonary disease (pooled OR 1.42, 95% CI 1.17 - 1.71; high certainty); chronic limb threatening ischaemia (pooled OR 1.67, 95% CI 1.22 - 2.29; moderate certainty); chronic kidney disease (pooled OR 2.13, 95% CI 1.18 - 3.83; moderate certainty); intra-operative (pooled OR 1.23, 95% CI 1.02 - 1.49), peri-operative (pooled OR 1.92, 95% CI 1.27 - 2.90), or post-operative (pooled OR 2.21, 95% CI 1.44 - 3.39) blood transfusion (moderate certainty for all); urgent or emergency surgery (pooled OR 2.12, 95% CI 1.22 - 3.70; moderate certainty); vein bypass and or patch instead of endarterectomy alone (pooled OR 1.86, 95% CI 1.33 - 2.59; moderate certainty); an operation lasting ≥ 3 hours (pooled OR 1.86, 95% CI 1.33 - 2.59; moderate certainty) or ≥ 5 hours (pooled OR 1.60, 95% CI 1.18 - 2.17; moderate certainty); and early or unplanned re-operation (pooled OR 4.50, 95% CI 2.18 - 9.32; low certainty).

CONCLUSION

This systematic review identified evidence informed SSI risk factors following lower limb revascularisation surgery. These may be used to develop improved SSI risk prediction tools and to identify patients who may benefit from evidence informed SSI prevention strategies.

Postoperative Outcomes and One-Year Mortality of Patients on Chronic Anticoagulation Medications Undergoing Infrainguinal Bypass

BACKGROUND

Patients requiring open infrainguinal bypass (IIB) frequently are taking chronic anticoagulation (AC) medications. Taking these medications in the preoperative setting may affect the outcomes of surgery. This study aims to evaluate postoperative outcomes and 1-year mortality of patients taking chronic AC medications that undergo IIB.

METHODS

Using data obtained from the Vascular Quality Initiative from January 2011 to October 2021, patients on warfarin or any direct oral anticoagulants (DOAC) within 30 days of IIB were compared with patients not taking chronic AC medications. The primary outcomes were in-hospital, 30-day, and 1-year mortality. The secondary outcomes included total procedure time, need for perioperative packed red blood cell transfusion, prolonged length of hospital stay, postoperative myocardial infarction or stroke, and graft patency at discharge. A subgroup analysis was performed comparing patients taking warfarin with those taking DOACs. Univariate analyses and multivariate logistic regression, Kaplan Meier survival, and Cox regression analyses were used to analyze the data for postoperative and 1-year outcomes, respectively.

RESULTS

A total of 55,076 patients underwent IIB during the study period, and 11,547 (20.97%) were on chronic AC prior to surgery. The 2 cohorts differed significantly in almost every demographic and clinical characteristic. Multivariate analyses adjusting for 45 potential confounders revealed that there was no significant difference in in-hospital, 30-day, and 1-year mortality. The total procedure time for the chronic AC cohort was on average 11.46 ± 2.16 min longer (P ≤ 0.001) and there was a greater risk of prolonged length of stay in the hospital (adjusted odds ratio [aOR]: 1.19, 95% confidence interval [CI]: 1.13-1.26, P < 0.001). These patients also returned to the operating room (OR) at a greater rate (aOR: 1.12, 95% CI: 1.05-1.19; P = 0.016) and demonstrated a significantly lower rate of graft patency at discharge (aOR: 0.73, 95% CI: 0.62-0.86, P = 0.001). On subgroup analysis, multivariate analysis demonstrated lower 30-day mortality for the DOAC group in comparison to the warfarin group (aOR: 0.74, 95% CI: 0.57-0.94, P = 0.015), but no significant differences in in-hospital and 1-year mortality.

CONCLUSIONS

Patients taking AC medications within 30 days prior to IIBs may require more perioperative red blood cell transfusions, longer hospitalizations, and return to the OR at a greater rate. They are also at an increased risk for loss of graft patency at discharge. However, these patients are not at increased risk of in-hospital, 30-day, or 1-year mortality. IIB can, therefore, be performed safely in patients taking chronic AC medications.

A systematic review and meta-analysis of primary bypass surgery compared with bypass surgery after endovascular treatment in peripheral artery disease patients

OBJECTIVE

Both bypass surgery and endovascular treatment are well-recognized interventions for the treatment of peripheral artery disease; however, the effect of failed endovascular treatment on subsequent surgeries remains controversial. A systematic review was conducted to compare the outcomes of primary bypass and bypass surgery after endovascular treatment.

METHODS

Three academic databases (Embase, PubMed, and Scopus) were searched from their inception to August 2022. Two independent investigators searched for studies that reported the outcomes of primary bypass surgery and bypass surgery after endovascular treatment in patients with peripheral artery disease. Abstracts and full-text studies were screened independently using duplicate data abstraction. Dichotomous outcome measures were reported using a random-effects model to generate a summary odds ratio (OR) and 95% confidence interval (CI). The risk of bias was assessed using the Newcastle-Ottawa Scale.

RESULTS

Seventeen retrospective observational studies were selected from 3911 articles and included 8064 patients, 6252 of whom underwent primary bypass surgery and 1812 underwent bypass surgery after endovascular treatment. The mean age was 69.0 years and 61.2% (n = 4938) were male. For perioperative outcomes, the 30-day results showed no difference in mortality (OR, 0.76; 95% CI, 0.53-1.10), or amputation (OR, 0.89; 95% CI, 0.67-1.20). For short- to mid-term outcomes, primary patency did not differ at 6 months (OR, 0.98; 95% CI, 0.81-1.19), 1 year (OR, 1.12; 95% CI, 0.97-1.30), or 2 years (OR, 1.17; 95% CI, 0.85-1.61) follow-up. Amputation-free survival did not differ at 6 months (OR, 1.03; 95% CI, 0.82-1.30), 1 year (OR, 1.09; 95% CI, 0.89-1.32), 2 years (OR, 1.18; 95% CI, 0.93-1.50), or 3 years (OR, 1.09; 95% CI, 0.84-1.40) of follow-up. No significant difference was found in overall survival or second patency.

CONCLUSIONS

This meta-analysis of retrospective, nonrandomized, observational studies suggests that prior endovascular treatment of lower extremity arterial disease does not result in worse perioperative, short-term, or mid-term clinical outcomes of subsequent infrainguinal bypass surgery compared with patients without prior endovascular treatment.

The natural history of chronic limb-threatening ischemia after technical failure of endovascular intervention

OBJECTIVES

The treatment for chronic limb-threatening ischemia (CLTI) has changed dramatically in the last few decades with a shift toward an endovascular-first approach and aggressive revascularization to achieve limb salvage. As the size of the CLTI population and intervention rates increase, patients will continue to experience technical failure (TF). Here, we describe the natural history of patients after TF of endovascular intervention for CLTI.

METHODS

We conducted a retrospective cohort study of patients with CLTI who attempted endovascular intervention or bypass at our multidisciplinary limb salvage center from 2013 to 2019. Patient characteristics were collected according to the Society for Vascular Surgery's reporting standards. Primary outcomes included survival, limb salvage, wound healing, and revascularization patency. Product-limit Kaplan-Meier estimated survival functions for these outcomes, and between-group comparisons were made using Mantel-Cox log-rank nonparametric tests.

RESULTS

We identified 242 limbs from 220 unique patients who underwent primary bypass (n = 30) or attempted endovascular intervention (n = 212) at our limb salvage center. Endovascular intervention was a TF in 31 (14.6%) limbs. After TF, 13 limbs underwent secondary bypass and 18 limbs were managed medically. Patients who experienced TF tended to be older (P < .001), male (P = .003), current tobacco users (P = .014), have longer lesions (P = .001), and have chronic total occlusions of target arteries (P < .001) as compared with those who experienced technical success. Furthermore, the TF group had worse limb salvage (P = .047) and slower wound healing (P = .028), but their survival was not different. Survival, limb salvage, and wound healing were not different in patients who received secondary bypass or medical management after TF. The secondary bypass group was older (P = .012) and had a lower prevalence of tibial disease (P = .049) than the primary bypass group and trended toward decreased survival, limb salvage, and wound healing (P = .059, P = .083, and P = .051, respectively).

CONCLUSIONS

Increased age, male sex, current tobacco use, longer arterial lesions, and occluded target arteries are associated with TF of endovascular intervention. Limb salvage and wound healing are relatively poor after TF of endovascular intervention, but survival appears comparable with patients who experience technical success. Secondary bypass may not always rescue patients after TF, though our sample size limits statistical power. Interestingly, patients who received a secondary bypass after TF trended toward decreased survival, limb salvage, and wound healing compared with primary bypass.

Is open surgery still the first line of treatment for long femoropopliteal lesions?

INTRODUCTION

Treatment of long femoropopliteal lesions remains a challenge for vascular physicians as patients often present with multilevel complex pathologies and consequently face a high amputation risk and associated mortality. This review aimed to assess the current state of optimal revascularizations for the treatment of long femoropopliteal lesions.

EVIDENCE ACQUISITION

An online literature research of medical databases for original articles and review articles on open and endovascular revascularization of femoropopliteal lesions was conducted using mesh terms.

EVIDENCE SYNTHESIS

There has been an accumulation of evidence over the last years that endovascular treatment is a feasible and enduring alternative to open surgery for treatment of long femoropopliteal lesions if the lesions are restricted to the superficial femoral artery. But when disease extends to the infragenual level venous bypass remains superior with regards to long-term patency, clinical improvement and limb-salvage.

CONCLUSIONS

While the role of venous bypass as a first-line treatment might be declining, especially in frail patients or claudicants, the superior clinical improvement and amputation-free survival highlighted in several trials, demonstrate the relevance of bypass surgery. More randomized clinical trials are needed to verify the non-inferiority of endovascular treatment options to open surgery, especially when arterial disease extends below the knee.

Outcomes and Fate of the Distal Landing Zone Compared Between Prosthetic and Autologous Grafts After Infra-Inguinal Graft Occlusions

Background

Due to an increasing life expectancy, more and more patients experience the failure of peripheral arterial revascularization. This study aims to investigate patients treated for the failure of infra-inguinal bypass grafts, and to investigate the interaction of different bypass materials [great saphenous vein (GSV) and polytetrafluoroethylene (PTFE)] and the further outcome.

Methods

Retrospective single-center analysis of consecutive patients treated for acute or chronic occlusion of infra-inguinal bypasses at a university hospital was conducted. Hospitalizations from 1st January 2010 through 31st December 2019 were included. Perioperative parameters from the index operation including graft material (prosthetic vs. autologous) were assessed. After bypass occlusion, the grade of ischemia, as well as the distal landing zone of the redo bypass compared with the primary bypass was investigated.

Results

In this study, 158 (65% men and 35% women with a m mean age of 70.5 years) eligible patients were included (57% vein and 42% prosthetic bypass grafts). After graft occlusion, 47% of the patients presented with symptoms of acute limb-threatening ischemia, 53% with symptoms of chronic leg ischemia. The rate of acute limb-threatening ischemia was significantly higher when prosthetic graft material was used during the index operation (p =0.016). Additionally, in case of reoperation, the landing zone of the redo bypass was significantly more distally located after occlusion of prosthetic bypass graft (p = 0.014)

Conclusion

Occlusions of prosthetic bypass grafts were associated with significantly higher rates of acute symptoms compared with vein grafts. Additionally, a shift to a more distal landing zone was recognized after the failure of a prosthetic bypass graft during the redo bypass operation.

Reinterventions in Patients with Claudication and Chronic Limb Threatening Ischemia

BACKGROUND

Patients with peripheral artery disease (PAD) present with claudication or chronic limb threatening ischemia (CLTI). CLTI patients have a more advanced stage of atherosclerosis and increased comorbidities compared to claudicants, and are at an elevated risk of major amputation and mortality after lower extremity revascularization (LER). However, the frequency of reinterventions for claudication and CLTI have not been compared. Our hypothesis is that patients with CLTI undergo more frequent reinterventions to prevent major amputation.

METHODS

A single-center retrospective chart review of consecutive patients undergoing lower extremity revascularization (LER) for PAD in 2013-2015 was performed. Patients were stratified based on indication for revascularization into claudication or CLTI. Patient characteristics, outcomes, and reinterventions were compared between the 2 groups.

RESULTS

There were 826 patients undergoing LER and 44% (N = 361) had CLTI. Patients treated for CLTI were more likely to be smokers (P < 0.001), to have diabetes (P< 0.001), chronic renal insufficiency (P< 0.001), end stage renal disease (P< 0.001), and cardiac disease (P< 0.001). CLTI patients were less likely to be on optimal medical management as reflected by decreased rate of aspirin (P< 0.001), ADP receptor/P2Y12 inhibitors (P< 0.001), and statins (P< 0.001) compared to patients with claudication. Patients with CLTI had significantly higher major amputation (3.7% vs. 0.2%, P< 0.001) and mortality (1.4% vs. 0.2%, P = 0.092) at 30 days. At long-term follow up, patients with CLTI had higher rates of major amputation (15.5% vs. 1.3%, P < 0.001) and mortality (37.1% vs. 18.1%, P < 0.001) compared to patients with claudication. There was a significant difference in mean follow-up time between the 2 cohorts (claudication: 3.7 ± 1.5 years versus CLTI: 2.6 ± 1.8 years, P < 0.001). There was no significant difference in the ipsilateral reintervention rate between the 2 groups (claudication: 39.6% vs. CLTI: 42.7%, P = 0.37) or the mean number of ipsilateral reinterventions (claudication: 2.0 ± 1.6 vs. CLTI: 2.0 ± 1.7). However, after adjusting for follow-up time, the mean number of reinterventions per year was significantly higher for CLTI patients compared to patients with claudication (1.4 ± 2.2 vs. .6 ± 0.7 intervention per year, P < 0.001).

CONCLUSIONS

Patients undergoing LER for CLTI undergo more frequent reinterventions over time compared to patients treated for claudication. Research on reinterventions after LER should include reporting of the frequency of reintervention adjusted for the follow up period in addition to the reintervention rate defined as the percentage of patients undergoing reintervention.

Covered stent grafts for relining of chronically occluded femoro-popliteal bypasses in frail patients

In four high-risk patients with chronically occluded femoro-popliteal bypass suffering from Rutherford 4-5 chronic limb threatening ischemia we performed, as an alternative for redo surgery, endovasculair relining with covered stent grafts. During follow-up (3, 8, 14 and 20 months) one patient had redo percutaneous intervention and eventually below-the-knee amputation.

The Upper-Arm Basilic-Cephalic Loop: A Valueable Alternative for Below-Knee Arterial Reconstruction

INTRODUCTION

Despite advances of endovascular interventions, bypass surgery remains the gold standard for treatment of long and complex arterial occlusions in the lower limb. Autologous vein is regarded superior to other options. As the graft of first choice, the great saphenous vein (GSV) is often not available due to previous bypass, stripping or poor quality. Other options like arm veins (AV) are important alternatives. As forearm portions of AVs are often unusable, a graft created from the upper arm basilic and cephalic veins provides a valuable alternative.

PATIENTS AND METHODS

We analyzed consecutive patients treated at an academic tertiary referral center between 01/1998 and 07/2018 using arm veins as the main peripheral bypass graft. Study endpoints were primary patency, secondary patency, limb salvage and survival.

RESULTS

In the observed time period 2702 bypass procedures were performed at our institution for below-knee arterial reconstructions. Vein grafts used included the ipsilateral GSV (iGSV; n = 1937/71.7%), contralateral GSV (cGSV; 192/7.1%), small saphenous vein (SSV; 133/4.9%), prosthetic conduits (61/2.3%) and different configurations of AV (379/14%). In the majority of patients receiving AV grafts a complete continuous cephalic or basilic vein (CAV) was used (n = 292/77%). If it was not possible to use major parts of these 2 veins, either spliced arm vein grafts (SAV) (42/11%) or an upper arm basilic-cephalic loop graft (45/12%) were used. Median follow-up was 27 (interquartile range: 8-50) months. After 3 years secondary patency (CAV: 85%; SAV: 62%; loop: 66%; p = 0.125) and limb salvage rates (CAV: 79%, SAV: 68%; loop: 79%; p = 0.346) were similar between the 3 bypass options.

CONCLUSION

The encouraging results of alternative AV configurations highlight their value in case the basilic or cephalic veins are not useable in continuity. Especially for infragenual redo-bypass procedures, these techniques should be considered to offer patients durable revascularization options.

Impact of prior endovascular interventions on outcomes of lower limb bypass surgery: A systematic review and meta-analysis

The aim of this meta-analysis was to evaluate the mortality, amputation and complication rates in patients with peripheral lower limb arterial disease undergoing bypass surgery with or without a prior history of endovascular operation. A systematic literature screen was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines on four academic databases, Medline, Scopus, Embase and Cochrane Central Register of Controlled Trials. Out of 1,072 records, six articles involving 11,420 patients (mean age, 68.1±2.0 years) met the inclusion criteria. The findings presented a 2b level of evidence (i.e. overall evidence represents data from individual cohort study or low quality randomized controlled trials) and suggested lower mortality, amputation and complication rates for patients undergoing bypass surgery without any history of endovascular operation, compared with those with a history of prior endovascular operation. Moreover, a random-effect meta-analysis suggested a small, positive reduction in mortality (Hedge's g=0.08), amputation (Hedge's g=0.18) and complication rates (Hedge's g=0.05) for patients undergoing bypass surgery without any history of endovascular operation. Nevertheless, owing to the scarcity of high-quality data, further studies and randomized clinical trials are needed to confirm these effects.

Arm Vein versus Small Saphenous Vein for Lower Extremity Bypass in the Absence of Both Great Saphenous Veins

BACKGROUND

Bypass surgery remains the gold standard for long and complex arterial occlusions in the lower limb. The vein is regarded superior to prosthetic conduits in peripheral arterial bypass surgery. However, this option is often limited because of previous bypass, stripping, or poor quality of the ipsilateral and/or contralateral great saphenous vein (GSV). Under these circumstances, the arm vein (AV) and small saphenous vein (SSV) are the only alternative autologous vein grafts.

METHODS

We analyzed all consecutive patients treated at an academic tertiary referral center between January 1998 and July 2018 using either the AV or SSV as the main peripheral bypass graft. Study end points were primary patency, secondary patency, limb salvage, and survival.

RESULTS

In total, 416 bypass procedures using exclusively AV (n = 327) or SSV (n = 89) were performed. There was a predominance of male gender. The majority of risk factors were evenly distributed between groups. The mean follow-up period was 2.3 years (0.9 to 13.3 years). Five-year primary and secondary patency rates were 39% (95% CI: 31-47%) and 67% (59-75%) for AV and 53% (41-66%) and 76% (67-86%) for SSV, respectively (P = 0.2 and 0.25). The five-year limb salvage and survival rates were 71% (68-81%) and 84% (77-90%) for AV and 78% (67-88%) and 90% (82-98%) for SSV, respectively (P = 0.52 and 0.11).

CONCLUSIONS

Both AV and SSV are equally effective alternatives for peripheral bypass if no GSV is available. Although there was a trend toward better results with the SSV, there was no significant difference between the 2 options.

Outcomes after Open Lower Extremity Revascularization in Patients with Critical Limb Ischemia

BACKGROUND

For decades, open intervention was the treatment of choice in patients requiring lower extremity revascularization. In the endovascular era, however, open and endovascular revascularization are options. The implications of prior revascularization on the outcomes for subsequent revascularization are not known. In the present study, we evaluated 30-day outcomes after open lower extremity revascularization for critical limb ischemia (CLI) in those who had previous interventions.

METHODS

The 2012-2017 open lower extremity bypass Participant User Data Files from the National Surgical Quality Improvement Program were used to identify a cohort of patients with CLI. Patients whose operation was considered emergent were excluded from the analysis. Patients were stratified on whether they had a previous open or endovascular intervention or undergoing a primary revascularization. The primary outcome measure was 30-day major adverse limb events (MALEs). Secondary outcomes included major adverse cardiac events (MACEs) and wound complications.

RESULTS

A total of 12,668 patients met study criteria with 59.6% (n = 7,549) undergoing a primary open revascularization, 22.4% (n = 2,839) having a prior endovascular intervention, and 18.0% (n = 2,280) having a prior open revascularization. There were notable differences in the baseline characteristics between the 3 groups. In addition, there were differences in the reason for intervention (rest pain versus tissue loss), type of revascularization, and type of conduit used between the 3 groups. After adjustment, a prior open revascularization was significantly associated with 30-day MALE when compared with a primary revascularization (adjusted odds ratio, 1.69; 95% confidence interval, 1.47-1.94; P < 0.001) and prior endovascular intervention (adjusted odds ratio, 1.76; 95% confidence interval, 1.46-2.12; P < 0.001). There were no differences in outcomes between primary revascularization and prior endovascular patients. There were no differences between MACEs or wound complications between the 3 groups.

CONCLUSIONS

A prior endovascular intervention does not seem to accrue any additional short-term risk when compared with primary revascularization, suggesting an endovascular-first approach may be a safe strategy in patients with CLI. However, a prior open intervention is significantly associated with 30-day MALE in patients undergoing redo open revascularization, which may be related to the rapid decline in patients once they have exhausted their best open revascularization option.

Proposed Classification of Incision Complications: Analysis of a Prospective Study on Elective Open Lower-Limb Revascularization

Background: Incision complications (IC) have a significant impact on procedure-related morbidity after lower-limb revascularization. One of the most studied IC is surgical site infection (SSI). Reporting these complications in a uniform way is crucial to evaluate treatment approaches. The aim of this study was to propose a comprehensive classification of IC and apply it to compare SSI with other IC in a trial on elective open lower-limb revascularization procedures. Methods: Two hundred twenty-three eligible patients undergoing elective unilateral inguinal and infra-inguinal arterial vascular surgery were extracted from a randomized controlled trial on incisional negative-pressure wound therapy (NPWT) on inguinal vascular surgical incisions. The IC were classified by grades of severity (grade 0-6) that focused on IC-related consequences such as out-patient treatment (grade 1), prolonged in-patient treatment (grade 2), re-admission (grade 3), and re-operation (grade ≥4). An SSI was defined by the ASEPSIS score criteria. Results: An SSI was diagnosed in 63 patients (28.3%). Thirty-five of 160 patients (21.8%) not suffering from SSI underwent IC treatment. Treatment for IC was recorded for 25/144 patients (17.4%) with satisfactory site healing as judged by the ASEPSIS score. The median incision-related in-hospital stay in those with SSI (n = 79) and disturbed healing (n = 16) according to the ASEPSIS score was 13 days in both groups (p = 0.53). Five patients had peri-vascular SSI (IC grade 4 n = 4; grade 5 n = 1). The proposed classification of IC and the ASEPSIS score correlated highly (r = 0.77; p < 0.001). Inter-rater reliability for IC grading was substantial for three investigators with different levels of experience (k = 0.81, 0.71, and 0.70). Conclusions: The proposed incision classification suggests a comparable clinical significance of vascular IC in terms of IC-related in-patient stay, whether there was a surgical site infection or not. This classification system requires external validation.

Extracorporeal shock wave-assisted adipose-derived fresh stromal vascular fraction restores the blood flow of critical limb ischemia in rat

We tested the hypothesis that extracorporeal-shock-wave (ECSW)-assisted adipose-derived stromal vascular fraction (SVF) therapy was better than either one for restoring the blood flow in critical limb ischemia (CLI). Adult male-SD rats were categorized into group 1 (sham-operated-control), group 2 (CLI), group 3 [CLI + ECSW (280 impulses/0.10 mJ/mm²) applied to left inguinal area at 3 h after CLI], group 4 [CLI + SVF (1.2 × 10⁶) implanted into CLI area at 3 h after CLI], group 5 (CLI + ECSW-SVF). In vitro studies showed that ECSW significantly enhanced angiogenesis in human umbilical-vein endothelial cells and carotid-artery ring, and SVF significantly suppressed inflammation (TNF-α/NF-Κb/IL-1ß/MMP-9) in smooth-muscle cells treated by LPS (all p < .001). By day 14 after CLI, the ratio of ischemic/normal blood flow (INBF) was highest in group 1, lowest in group 2, significantly higher in group 5 than in groups 3 and 4, but no difference was shown between the latter two groups (all p < .001). The fibrotic area in CLI region exhibited an opposite pattern of INBF ratio (all p < .0001). Protein (CD31/vWF/eNOS) and cellular (CD31/vWF) expressions and number of small vessels in CLI area exhibited an identical pattern, whilst protein expressions of apoptotic (caspase3/PARP/mitochondrial-Bax) fibrotic/DNA-damaged (Samd3/TFG-ß/γ-H2AX) biomarkers exhibited an opposite pattern to INBF among five groups (all p < .0001). The numbers of angiogenetic cells in CLI region (SDF-1α/VEGF/CXCR4) and endothelial-progenitor cells (C-kit/CD31+//Sca-1/CD31+//CD34/KDR+/VE-cadherin/CD34+) in circulation significantly and progressively increased from groups 2 to 5 (all p < .0001). In conclusion, ECSW-SVF therapy effectively enhanced angiogenesis and restoration of blood flow in CLI area.

Objective Performance Goals for Surgical Treatment of Critical Limb Ischemia

BACKGROUND

Based on prospective vein bypass trials for lower leg ischemia, objective performance goals (OPG) were established by the Society for Vascular Surgery (SVS) and are used as a benchmark tool for open and endovascular treatments. This study aims to analyze OPG of all patients with critical limb ischemia (CLI) treated by open revascularization techniques at a tertiary care facility in routine practice.

METHODS

From January 2005 to March 2013, 315 patients (mean age 72 years) with CLI were retrospectively included in this study. Inclusion criteria were patients with Fontaine stage III and IV, realized revascularization with open surgical procedures (bypass grafting or endarterectomy), or hybrid method (open + endovascular). Exclusion criteria were primary major amputations, patients with revascularization treatments of the index leg within the last 3 months, and missing aftercare. Primary end point was "amputation-free survival" (AFS), and secondary end point was "freedom from major adverse limb event + perioperative death (30 days)" (MALE + POD) according to the SVS. The technical end point was primary patency. Mean follow-up was 34 months. The following variables were studied: clinical stage (Fontaine), previous interventions, bypass material used, and site of the distal anastomosis. The statistical evaluation and preparation was carried out using the Kaplan-Meier estimator and the log-rank test. A multivariate analysis was performed using the Cox proportional hazards model. A P value ≤0.05 was considered to be statistically significant.

RESULTS

A total of 128 patients (31%) fulfilling the adjusted SVS OPG criteria showed significantly better results for AFS, MALE + POD, and primary patency (P = 0.013, P = 0.015, P = 0.002, respectively). Regarding the AFS (1 year: 74%), multivariate analysis displayed significant worse results for patients with end-stage renal disease (hazard ratio [HR] 2.90, 95% confidence interval [CI] 1.83-4.60, P < 0.001) and Fontaine stage IV (HR 1.69, 95% CI 1.11-2.57, P = 0.015). Regarding MALE + POD (1 year: 64%), male patients (HR 0.64, 95% CI 0.46-0.90, P = 0.011) showed a significantly better outcome and patients without previous interventions of the index leg (HR 1.51, 95% CI 1.09-2.09, P = 0.013) showed a significantly worse outcome.

CONCLUSIONS

In this study, we were able to show that it is possible to reach the efficacy of OPGs set by SVS in a surgically treated all-comers cohort of CLI patients. Nevertheless, patients who did not fulfill the SVS OPG criteria showed significantly worse results for AFS and MALE + POD.

Patient selection and perioperative outcomes of bypass and endovascular intervention as first revascularization strategy for infrainguinal arterial disease

OBJECTIVE

The optimal initial revascularization strategy remains uncertain for patients with peripheral arterial disease. The purpose of this study was to evaluate current nationwide selection and perioperative outcomes of patients undergoing bypass or endovascular intervention for infrainguinal disease in those with no prior ipsilateral revascularization.

METHODS

Patients undergoing nonemergent first-time infrainguinal revascularization were identified in the Targeted Vascular module of the National Surgical Quality Improvement Program (NSQIP) for 2011 to 2014 and stratified by symptom status (chronic limb-threatening ischemia [CLTI] or claudication). Patients treated with endovascular intervention were compared with those who underwent bypass. Multivariable logistic regression was used to evaluate current selection of patients and to establish independent associations between first-time procedures and postoperative outcomes.

RESULTS

Of 5998 first-time infrainguinal revascularizations performed, 3193 were bypass procedures (63% for CLTI) and 2805 were endovascular interventions (64% for CLTI). Current patient characteristics associated with an endovascular-first approach as opposed to bypass-first in CLTI patients were age ≥80 years, tissue loss, nonsmoking, functional dependence, diabetes, dialysis, and tibial lesions, whereas age ≥80 years, nonwhite race, nonsmoking, diabetes, and tibial lesions were associated with an endovascular approach for claudication. In comparing first-time endovascular intervention with bypass, there was no difference in 30-day mortality in CLTI patients (univariate: 2.1% vs 2.2%; adjusted: odds ratio [OR], 0.7; 95% confidence interval [CI], 0.4-1.1) or claudication patients (0.3% vs 0.6%). Among CLTI patients, endovascular-first intervention was associated with lower rates of major adverse cardiovascular event (3.6% vs 4.7%; OR, 0.6; 95% CI, 0.4-0.9), surgical site infection (0.9% vs 7.7%; OR, 0.1; 95% CI, 0.1-0.2), bleeding (8.5% vs 17%; OR, 0.4; 95% CI, 0.3-0.5), unplanned reoperation (13% vs 17%; OR, 0.7; 95% CI, 0.5-0.8), and unplanned readmission (17% vs 18%; OR, 0.8; 95% CI, 0.7-0.9). Patients with claudication undergoing endovascular-first intervention also had lower rates of major adverse cardiovascular event (0.8% vs 1.6%; OR, 0.4; 95% CI, 0.2-0.95), surgical site infection (0.7% vs 6.6%; OR, 0.1; 95% CI, 0.04-0.2), bleeding (2.3% vs 6.0%; OR, 0.3; 95% CI, 0.2-0.5), unplanned reoperation (4.3% vs 6.6%; OR, 0.6; 95% CI, 0.4-0.9), and unplanned readmission (5.9% vs 9.0%; OR, 0.6; 95% CI, 0.4-0.8). Conversely, endovascular-first intervention was associated with a higher rate of secondary revascularizations within 30 days for CLTI (4.3% vs 3.1%; OR, 1.6; 95% CI, 1.04-2.3) but not for claudication (2.6% vs 1.9%; OR, 1.7; 95% CI, 0.9-3.4).

CONCLUSIONS

An endovascular-first approach as a revascularization strategy for infrainguinal disease was associated with substantially lower early morbidity but not mortality, at the cost of higher rates of postoperative secondary revascularizations. As a national representation of first-time revascularizations, this study highlights the early endovascular perioperative benefit, although more robust long-term data are needed to adopt either one strategy or the other in select patients with peripheral arterial disease.