Dynamic Perioperative Platelet Activity and Cardiovascular Events in Peripheral Artery Disease.

OBJECTIVE: Patients with peripheral artery disease (PAD) undergo lower extremity revascularization (LER) for symptomatic relief or limb salvage. Despite LER, patients remain at increased risk of platelet-mediated complications, such as major adverse cardiac and limb events (MACLE). Platelet activity is associated with cardiovascular events; yet little is known about the dynamic nature of platelet activity over time. We therefore investigated the change in platelet activity over time and its association with long-term cardiovascular risk. METHODS: Patients with PAD undergoing LER were enrolled into the multicenter, prospective Platelet Activity and Cardiovascular Events (PACE) study. Platelet aggregation was assessed by light transmission aggregometry (LTA) to submaximal epinephrine (0.4µ M) immediately prior to LER, and on post-operative day 1 or 2 (POD1) and 30 (POD30). A hyperreactive platelet phenotype was defined as >60% aggregation. Patients were followed longitudinally for MACLE, defined as the composite of death, myocardial infarction, stroke, major lower extremity amputation, or acute limb ischemia leading to reintervention. RESULTS: Among 287 patients undergoing LER, mean age was 70 ± 11 years, 33% were female, 61% were white, and 89% were on baseline antiplatelet therapy. Platelet aggregation to submaximal epinephrine induced a bimodal response; 15.5%, 16.8%, and 16.4% of patients demonstrated a hyperreactive platelet phenotype at baseline, POD1, and POD30, respectively. Platelet aggregation increased by 18.5% (P=0.001) from baseline to POD1, which subsequently returned to baseline at POD30. After a median follow-up of 19 months, MACLE occurred in 165 (57%) patients. After adjustment for demographics, clinical risk factors, procedure type, and antiplatelet therapy, platelet hyperreactivity at POD1 was associated with a significant hazard of long-term MACLE (aHR 4.61, 95% CI 2.08-10.20, P<0.001). CONCLUSION: Among patients with severe PAD, platelet activity increases following LER. Platelet hyperreactivity to submaximal epinephrine on POD1 is associated with long-term MACLE. Platelet activity following LER may represent a modifiable biomarker associated with excess cardiovascular risk.

Association of anemia and transfusion with major adverse cardiac events and major adverse limb events in patients undergoing open infrainguinal bypass.

INTRODUCTION: Anemia is highly prevalent patients with peripheral vascular disease and has been associated with postoperative cardiac events and mortality, and adverse limb events after revascularization procedures. Allogenic blood transfusions have also been associated with adverse events including hospital acquired infections, cardiac morbidity and reduced survival. The aim of this study was to evaluate the impact of blood transfusion on major adverse cardiac events (MACE) and major adverse limb events (MALE) in patients undergoing infrainguinal lower extremity bypass operations. METHODS: We performed a retrospective cohort analysis of patients undergoing infrainguinal lower extremity bypass in the Society for Vascular Surgery Vascular Quality Initiative database between 2003 and 2020. Patients were first grouped by their preoperative hemoglobin (Hgb) number (severe anemia: Hgb 7-10g/dL; moderate anemia: 10-12g/dL; normal Hgb: >12g/dL) and then stratified by their transfusion status (perioperative transfusion vs. no perioperative transfusion). Primary endpoints were MACE, defined as myocardial infarction, new congestive heart failure, dysrhythmia, or stroke in the postoperative period, and MALE, defined as return to operating room for thrombosis, loss of primary patency on follow-up and major ipsilateral amputation on follow-up. Secondary outcomes included wound complications, graft infections, 30-day mortality and 1-year survival. Outcomes were compared between patients who received transfusions and those who did not at every anemic threshold. Multivariable logistic regression was performed to evaluate the impact of blood transfusion on primary outcomes. RESULTS: A total of 55,884 patients were included for analysis, of which 16.3% had severe anemia, 25.9% had moderate anemia and 57.8% had normal hemoglobin. Anemia severity was associated with increased rates of MACE (9.8% vs. 8.3% vs. 5.2%, p<0.0001) and MALE (32.2% vs. 24.8% vs. 18.6%, p<0.0001). On univariate analysis, transfusion was consistently associated with increased rates of MACE and MALE at every anemic threshold (p<0.0001 for all). Transfusion was also associated with increased rates of 30-day mortality at all anemic thresholds (p<0.0001 for all) and reduced 1-year survival at all anemic thresholds (log-rank p<0.0001 for all). On multivariable analysis for MACE, an interaction factor was observed between preoperative Hgb and transfusion status (p<0.0001). At every anemic threshold, transfusion was independently associated with MACE (severe: OR 2.4 [95% CI: 2.0 - 2.9]; moderate: OR 2.8 [95% CI: 2.5 - 3.2]; normal: OR 4.5 [95% CI: 4.0 - 5.0]). On multivariable analysis for MALE, an interaction factor was also observed between preoperative Hgb and transfusion status (p<0.0001). At every anemic threshold, transfusion was independently associated with MALE (severe: OR 2.1 [95% CI: 1.9 - 2.3]; moderate: OR 1.8 [95% CI: 1.7 - 2.0]; normal: OR 2.6 [95% CI: 2.4 - 2.8]). CONCLUSIONS: Perioperative blood transfusion in patients undergoing infrainguinal lower extremity bypass is independently associated with MACE and MALE in all patients with preoperative Hgb > 7 g/dL. Despite the morbidities associated with anemia, these findings highlight that transfusion may not be the optimal treatment modality, particularly in patients with higher preoperative Hgb. Future research is needed to define the transfusion threshold in this population.

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are associated with improved amputation-free survival in chronic limb-threatening ischemia.

BACKGROUND: In the Heart Outcomes Prevention Evaluation study, investigators found that ramipril was associated with improved survival as well as decreased MI and stroke rates in patients with peripheral arterial disease. Nonetheless, their effect on chronic limb-threatening ischemia (CLTI)-specific outcomes is unclear. We aim to assess the effect of ACEIs/ARBs on amputation-free survival in patients with CLTI undergoing peripheral vascular intervention (PVI) in a Medicare-linked database. METHODS: Patients undergoing PVI in the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database were included. Primary outcomes included amputation-free survival. Kaplan-Meier survival and multivariable Cox regression analyses were used to assess 1-year outcomes. RESULTS: A total of 34,284 patients were included, 46.3% of whom were discharged on ACEIs/ARBs. Patients discharged on ACEIs/ARBs were more likely to be smokers, have diabetes, and have hypertension. They were also more likely to present with rest pain. The overall 1-year survival rate for patients on ACEIs/ARBs vs those who are not was (79.1% vs 69.4%; P < .001). Freedom from amputation was 87.8% for patients on ACEIs/ARBs vs 84.2% for those who were not (P < .001). Amputation-free survival was 70.5% vs 59.5% for ACEIs/ARBs vs no ACEIs/ARBs (P < .001). After adjusting for potential confounders, ACEIs/ARBs use was associated with lower 1-year mortality (hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.7-0.8; P < .001), amputation (HR, 0.89; 95% CI, 0.8-0.9; P < .001), and amputation or death (HR, 0.79; 95% CI, 0.76-0.8; P < .001). CONCLUSIONS: ACEIs/ARBs were associated independently with lower amputation, improved survival, and amputation-free rates survival at 1 year in patients with CLTI undergoing PVI. The fact that more than one-half the patients were not discharged on these medications presents an area for potential quality improvement.

The impact of diabetes mellitus on the outcomes of revascularization for chronic limb-threatening ischemia in the BEST-CLI trial.

OBJECTIVE: Several observational studies have demonstrated an association between diabetes mellitus (DM) and above-ankle amputation after lower extremity revascularization (LER). However, data from prospective randomized trials is lacking. This analysis compares the outcomes of patients with and without DM enrolled in the Best Endovascular vs Best Surgical Therapy in patients with Chronic Limb-Threatening Ischemia (BEST-CLI) trial. METHODS: Baseline characteristics were compared between patients with and without DM in the BEST-CLI trial. Cox regression was used to determine the association between DM and major outcomes of major adverse limb events (MALE), reintervention, above-ankle amputation, and all-cause death. RESULTS: Among 1777 patients who underwent LER, 69.2% had DM. Compared with patients without DM, those with DM were significantly younger, less likely to be White, and more likely to be Hispanic. Patients with DM were more likely to have hypertension, hyperlipidemia, coronary artery disease, congestive heart failure, and renal disease and be on optimal medical therapy (antiplatelets and statins), whereas patients without DM were significantly more likely to be smokers and have chronic obstructive pulmonary disease. Patients with DM were significantly more likely to present with late Wound Ischemia foot Infection (WIfI) stages (3-4) (73.7% vs 45.9%; P < .001) that were driven predominantly by differences in wound and infection grade. Conversely, patients without DM had significantly lower ankle pressures and toe pressures and were significantly more likely to have WIfI ischemia grade 3 compared with patients with DM (60% vs 52.5%; P = .016). At 3 years, patients with DM exhibited higher rates of above-ankle amputation and all-cause death compared with patients without DM. Kaplan-Meier analysis demonstrated significantly higher MALE or all-cause death compared with patients without DM (3-year estimate: 53.5% vs 46.4%; P < .001). After adjusting for potential confounders, regression analysis demonstrated that DM was independently associated with increased above-ankle amputation (1.75 [1.22-2.51]), all-cause death (1.63 [1.31-2.03]), and MALE or all-cause death (1.24 [1.04-1.47]). CONCLUSIONS: Patients with DM undergoing LER for chronic limb-threatening ischemia experienced a greater incidence of MALE or all-cause death compared with patients without DM. The impact of DM seems to be mediated by more severe wounds and infections at the time of presentation, and a higher prevalence of cardiac and renal disease.

Antithrombotic Therapy in Patients Undergoing Peripheral Artery Interventions.

Patients with peripheral artery disease (PAD) who undergo lower extremity revascularization (LER) are at high risk for cardiovascular and limb-related ischemic events. The role of antithrombotic therapy is to prevent thrombotic complications, but this requires balancing increased risk of bleeding events. The dual pathway inhibition (DPI) strategy including aspirin and low-dose rivaroxaban after LER has been shown to reduce major adverse cardiovascular and limb-related events without significant differences in major bleeding. There is now a need to implement the broad adoption of DPI therapy in PAD patients who have undergone LER in routine practice.

Mortality and Morbidity After Open Surgical Lower Extremity Revascularization in Patients With Peripheral Artery Disease and Concurrent Abdominal Stoma.

OBJECTIVES: Patients with peripheral artery disease (PAD) often require treatment with open lower extremity revascularization (LER). Patients with PAD often have other comorbidities and associated conditions that affect procedural outcomes, including abdominal stomas. The aim of this work is to investigate the impact that stomas may have on postoperative outcomes and complications. METHODS: We performed a 5-year (2016-2020) analysis of the Nationwide Readmission Database. We identified all adult patients undergoing open LER. These patients were categorized into 2 groups: stoma and no-stoma. Propensity score matching (1:1) was used to control for demographics and comorbidities. Index admission outcomes and readmission rate were examined. RESULTS: 212,275 open LER patients were identified. A matched cohort of 3088 patients (1:1 stoma vs no-stoma) was obtained. Patients with stomas had higher rates of several postoperative complications: acute posthemorrhagic anemia (29.1%, P < 0.01), acute kidney injury (21.4%, P < 0.001), index sepsis (10.3%, P < 0.001), and index SSI (2.8%, P < 0.001). There were no significant statistical differences between the 2 groups for acute myocardial infarction. Those with stomas had worse outcomes: greater in-hospital mortality (4.7%, P < 0.05), length of stays (median 7 days, P < 0.001), total charges (median 108,037 dollars, P < 0.001), discharges to long-term care facilities (30.8%, P < 0.001), discharges to their own homes needing home health care (30.1%, P < 0.001), 30-day readmission rates (23.2%, P < 0.01), and 30-day readmission mortality (6.1%, P < 0.01). CONCLUSIONS: Concurrent abdominal stoma is associated with increased postoperative morbidity and mortality after open LER. Further prospective studies are needed to validate these results.

Presentation and patterns of reinterventions after revascularization in patients with premature peripheral arterial disease.

OBJECTIVE: Premature peripheral arterial disease (PAD) (age ≤50 years) has been shown to negatively impact the outcomes of lower extremity revascularization (LER). Patients with premature PAD have an increased risk of major amputation compared with older patients. The primary goal of this study is to compare the frequency of reinterventions after LER in patients with premature PAD to their older counterparts with common age of presentation (ie, 60-80 years). METHODS: A retrospective review of consecutive patients undergoing LER for PAD in a single center was performed. Clinical, procedural, and socioeconomic characteristics were compared between patients with premature PAD and the older group. Perioperative and long-term outcomes were captured and compared including mortality, major amputation, reintervention rate and frequency, as well as major adverse limb events. RESULTS: There were 1274 patients who underwent LER (4.3% premature, 61.8% age 60-80). Patients with premature PAD were more likely to be females of racial minorities. Notably, the mean Distressed Communities Index score was significantly higher in the premature PAD group compared with the older patients. Patients with premature PAD were significantly more likely to have end-stage renal disease but less likely to have hypertension, hyperlipidemia, and coronary artery disease compared with older patients. There was no significant difference in perioperative complications. After a mean follow-up of 5 years, patients with premature PAD were significantly more likely to undergo more frequent reinterventions compared with older patients. Kaplan-Meier curves showed similar overall survival and major adverse limb event-free survival between the two groups. CONCLUSIONS: Patients with premature PAD are likely to undergo more frequent reinterventions after initial LER and have similar 5-year survival curves compared with patients at least 20 years older. Demographic and socioeconomic differences impacting patients with premature PAD, even in this relatively underpowered institutional experience, are striking and warrant further investigation.

Real-world application of Wound, Ischemia, and foot Infection scores in peripheral arterial disease patients.

OBJECTIVE: The Society for Vascular Surgery (SVS) Wound, Ischemia, and foot Infection (WIfI) classification system aims to risk stratify patients with chronic limb-threatening ischemia (CLTI), predicting both amputation rates and the need for revascularization. However, real-world use of the system and whether it predicts outcomes accurately after open revascularization and peripheral interventions is unclear. Therefore, we sought to determine the adoption of the WIfI classification system within a contemporary statewide collaborative as well as the impact of patient factor, and WIfI risk assessment on short- and long-term outcomes. METHODS: Using data from a large statewide collaborative, we identified patients with CLTI undergoing open surgical revascularization or peripheral vascular intervention (PVI) between 2016 and 2022. The primary exposure was preoperative clinical WIfI stage. Patients were categorized according to the SVS Lower Extremity Threatened Limb Classification System into clinical WIfI stages 1, 2, 3, or 4. The primary outcomes were 30-day and 1-year amputation and mortality rates. Multivariable logistic regression was performed to estimate the association of WIfI stage on postrevascularization outcomes. RESULTS: In the cohort of 17,417 patients, 83.4% (n = 14,529) had WIfI stage documented. PVIs were performed on 57.6% of patients, and 42.4% underwent an open surgical revascularization. Of the patients, 49.5% were classified as stage 1, 19.3% stage 2, 12.8% stage 3, and 18.3% of patients met stage 4 criteria. Stage 3 and 4 patients had higher rates of diabetes, congestive heart failure, and renal failure, and were less likely to be current or former smokers. One-half of stage 3 patients underwent open surgical revascularization, whereas stage 1 patients were most likely to have received a PVI (64%). As WIfI stage increased from 1 to 4, 1-year mortality increased from 12% to 21% (P < .001), 30-day amputation rates increased from 5% to 38% (P < .001), and 1-year amputation rates increased from 15% to 55% (P < .001). Finally, patients who did not have WIfI scores classified had significantly higher 30-day and 1-year mortality rates, as well as higher 30-day and 1-year amputation rates. CONCLUSIONS: The SVS WIfI clinical stage is significantly associated with 1-year amputation rates in patients with CLTI after lower extremity revascularization. Because nearly 55% of stage 4 patients require a major amputation within 1 year of intervention, this finding study supports use of the WIfI classification system in clinical decision-making for patients with CLTI.

Perioperative complications of minor and major reinterventions for peripheral arterial disease.

INTRODUCTION: Patients with peripheral arterial disease (PAD) frequently require reinterventions after lower-extremity revascularization (LER) to maintain perfusion. Current Society for Vascular Surgery guidelines define reinterventions as major or minor based on the magnitude of the procedure. While prior studies have compared primary LER procedures of different magnitudes, similar studies for reinterventions have not been performed. The objective of this study is to compare perioperative outcomes associated with major and minor reinterventions. METHODS: Patients undergoing LER for PAD at a tertiary care center from 2013 to 2017 were included. A retrospective review of electronic medical records was performed, and reinterventions were categorized as major or minor based on the procedure magnitude. Minor reinterventions included endovascular procedures and open revision with patch angioplasty, while major reinterventions were characterized by open surgical or endovascular LER with catheter-directed thrombolysis (CDT). Perioperative outcomes following LER were captured and compared for major and minor reinterventions. An additional subgroup analysis was performed comparing outcomes associated with major reinterventions stratified into open major surgical reinterventions and CDT. RESULTS: This study included 713 patients over a mean follow-up of 2.5 years. A total of 291 patients underwent 696 ipsilateral reinterventions (range = 1-12 reinterventions). Most reinterventions were minor (72.1%, N = 502) and 27.9% (N = 194) were major. Patients receiving reinterventions had an average age of 67.2 ± 11.5 and most were white (73.5%) males (60.1%) initially treated for claudication (58.2%) and CLTI (41.8%). There was significantly higher post-operative bleeding (9.8% vs 3.4%, p = .001), arterial thrombosis (3.1% vs 1.0%, p = .047), and acute renal failure (6.2% vs 2.4%, p = .014) after major reinterventions than minor. Additionally, major reinterventions had significantly higher return to the OR (17.0% vs 11.3%, p = .046) and longer hospital stays (7.5 vs 4.3 days, p = <.0001). Overall, major reinterventions were associated with significantly increased perioperative morbidity (37.6% vs 19.7%, p ≤ .001) with no difference in perioperative mortality. In the subgroup analysis, open reinterventions resulted in significantly longer hospital stays (8.6 days vs 5.5 days, p ≤ .001) and more wound infections than CDT (11.0% vs 0%, p = .017). However, there was no other significant difference in morbidity or mortality following treatment with open surgical reinterventions or CDT. CONCLUSIONS: In this study, major reinterventions after LER were associated with greater perioperative morbidity than minor reinterventions, with no difference in mortality. Major reinterventions performed via open surgery and CDT had similar morbidity and mortality.

Ischemia-Guided Coronary Revascularization Following Lower-Extremity Revascularization Improves 5-Year Survival of Patients With Chronic Limb-Threatening Ischemia.

PURPOSE: To determine whether diagnosis of asymptomatic (silent) coronary ischemia using coronary computed tomography (CT)-derived fractional flow reserve (FFRCT) together with targeted coronary revascularization of ischemia-producing coronary lesions following lower-extremity revascularization can reduce adverse cardiac events and improve long-term survival of patients with chronic limb-threatening ischemia (CLTI). MATERIALS AND METHODS: Prospective cohort study of CLTI patients with no cardiac history or symptoms undergoing elective lower-extremity revascularization. Patients with pre-operative coronary computed tomography angiography (CTA) and FFRCT evaluation with selective post-operative coronary revascularization (FFRCT group) were compared with patients with standard pre-operative evaluation and no post-operative coronary revascularization (control group). Lesion-specific coronary ischemia was defined as FFRCT≤0.80 distal to a coronary stenosis with FFRCT≤0.75 indicating severe ischemia. Endpoints included all-cause death, cardiac death, myocardial infarction (MI) and major adverse cardiovascular (CV) events (MACE=CV death, MI, stroke, or unplanned coronary revascularization) during 5 year follow-up. RESULTS: In the FFRCT group (n=111), FFRCT analysis revealed asymptomatic (silent) coronary ischemia (FFRCT≤0.80) in 69% of patients, with severe ischemia (FFRCT≤0.75) in 58%, left main ischemia in 8%, and multivessel ischemia in 40% of patients. The status of coronary ischemia in the control group (n=120) was unknown. Following lower-extremity revascularization, 42% of patients in FFRCT had elective coronary revascularization with no elective revascularization in controls. Both groups received guideline-directed medical therapy. During 5 year follow-up, compared with control, the FFRCT group had fewer all-cause deaths (24% vs 47%, hazard ratio [HR]=0.43 [95% confidence interval [CI]=0.27-0.69], p<0.001), fewer cardiac deaths (5% vs 26%, HR=0.18 [95% CI=0.07-0.45], p<0.001), fewer MIs (7% vs 28%, HR=0.21 [95% CI=0.10-0.47], p<0.001), and fewer MACE events (14% vs 39%, HR=0.28 [95% CI=0.15-0.51], p<0.001). CONCLUSIONS: Ischemia-guided coronary revascularization of CLTI patients with asymptomatic (silent) coronary ischemia following lower-extremity revascularization resulted in more than 2-fold reduction in all-cause death, cardiac death, MI, and MACE with improved 5 year survival compared with patients with standard cardiac evaluation and care (76% vs 53%, p<0.001). CLINICAL IMPACT: Silent coronary ischemia in patients with chronic limb-threatening ischemia (CLTI) is common even in the absence of cardiac history or symptoms. FFRCT is a convenient tool to diagnose silent coronary ischemia perioperatively. Our data suggest that post-surgery elective FFRCT-guided coronary revascularization reduces adverse cardiac events and improves long-term survival in this very-high risk patient group. Randomized study is warranted to finally test this concept.

Predicting wound complications following lower extremity revascularization.

OBJECTIVE: The aim of this study was to create a simple risk score to identify factors associated with wound complications after infrainguinal revascularization. METHODS: The Veterans Affairs Surgical Quality Improvement Program national data set was queried from 2005 to 2021 to identify 22,114 patients undergoing elective open revascularization for peripheral arterial disease (claudication, rest pain, tissue loss) or peripheral aneurysm. Emergency and trauma cases were excluded. The data set was divided into a two-thirds derivation set and one-third validation set to create a risk prediction model. The primary end point was wound complication (wound dehiscence, superficial/deep wound surgical site infection). Eight independent risk factors for wound complications resulted from the model and were assigned whole number integer risk scores. Summary risk scores were collapsed into categories and defined as low (0-3 points), moderate (4-7 points), high (8-11 points), and very high (>12 points). RESULTS: The wound complication rate in the derivation data set was 9.7% (n = 1428). Predictors of wound complication included age ≤73 (odds ratio [OR], 1.25; 95% confidence interval [CI], 1.08-1.46), body mass index ≥35 kg/m2 (OR, 1.99; 95% CI, 1.68-2.36), non-Hispanic White (vs others: OR, 1.48; 95% CI, 1.30-1.69), diabetes (OR, 1.23; 95% CI, 1.10-1.37), white blood cell count >9900/mm3 (OR, 1.18; 95% CI, 1.03-1.35), absence of coronary artery disease (OR, 1.27; 95% CI, 1.03-1.35), operative time >6 hours (OR, 1.20; 95% CI, 1.05-1.37), and undergoing a femoral endarterectomy in conjunction with bypass (OR, 1.34; 95% CI, 1.14-1.57). In both the derivation and validation sets, wound complications correlated with risk category. Among the defined categories in the derivation set, wound complication rates were 4.5% for low-risk patients, 8.5% for moderate-risk patients, 13.8% for high-risk patients, and 23.8% for very high-risk patients, with similar results for the internal validation data set. Operative indication did not independently associate with wound complications. Patients with wound complications had higher rates of reoperation and graft failure. CONCLUSIONS: This risk prediction model uses easily obtainable clinical metrics that allow for informed discussion of wound complication risk for patients undergoing open infrainguinal revascularization.

Including socioeconomic status reduces readmission penalties to safety-net hospitals.

OBJECTIVE: Medicare's Hospital Readmissions Reduction Program (HRRP) financially penalizes "excessive" postoperative readmissions. Concerned with creating a double standard for institutions treating a high percentage of economically vulnerable patients, Medicare elected to exclude socioeconomic status (SES) from its risk-adjustment model. However, recent evidence suggests that safety-net hospitals (SNHs) caring for many low-SES patients are disproportionately penalized under the HRRP. We sought to simulate the impact of including SES-sensitive models on HRRP penalties for hospitals performing lower extremity revascularization (LER). METHODS: This is a retrospective, cross-sectional analysis of national data on Medicare patients undergoing open or endovascular LER procedures between 2007 and 2009. We used hierarchical logistic regression to generate hospital risk-standardized 30-day readmission rates under Medicare's current model (adjusting for age, sex, comorbidities, and procedure type) compared with models that also adjust for SES. We estimated the likelihood of a penalty and penalty size for SNHs compared with non-SNHs under the current Medicare model and these SES-sensitive models. RESULTS: Our study population comprised 1708 hospitals performing 284,724 LER operations with an overall unadjusted readmission rate of 14.4% (standard deviation: 5.3%). Compared with the Centers for Medicare and Medicaid Services model, adjusting for SES would not change the proportion of SNHs penalized for excess readmissions (55.1% vs 53.4%, P = .101) but would reduce penalty amounts for 38% of SNHs compared with only 17% of non-SNHs, P < .001. CONCLUSIONS: For LER, changing national Medicare policy to including SES in readmission risk-adjustment models would reduce penalty amounts to SNHs, especially for those that are also teaching institutions. Making further strides toward reducing the national disparity between SNHs and non-SHNs on readmissions, performance measures require strategies beyond simply altering the risk-adjustment model to include SES.

Outcomes of lower extremity revascularization in octogenarians and nonagenarians for intermittent claudication.

OBJECTIVE: Revascularization for intermittent claudication (IC) due to infrainguinal peripheral arterial disease (PAD) is dependent on durability and expected benefit. We aimed to assess outcomes for IC interventions in octogenarians and nonagenarians (age ≥80 years) and those younger than 80 years (age <80 years). METHODS: The Vascular Quality Initiative was queried (2010-2020) for peripheral vascular interventions (PVIs) and infrainguinal bypasses (IIBs) performed to treat IC. Baseline characteristics, procedural details, and outcomes were analyzed (comparing age ≥80 years and age <80 years). RESULTS: There were 84,210 PVIs (12.1% age ≥80 years and 87.9% age <80 years) and 10,980 IIBs (7.4% age ≥80 years and 92.6% age <80 years) for IC. For PVI, patients aged ≥80 years more often underwent femoropopliteal (70.7% vs 58.1%) and infrapopliteal (19% vs 9.3%) interventions, and less often iliac interventions (32.1% vs 48%) (P < .001 for all). Patients aged ≥80 years had more perioperative hematomas (3.5% vs 2.4%) and 30-day mortality (0.9% vs 0.4%) (P < .001). At 1-year post-intervention, the age ≥80 years cohort had fewer independently ambulatory patients (80% vs 91.5%; P < .001). Kaplan-Meier analysis showed patients aged ≥80 years had lower reintervention/amputation-free survival (81.4% vs 86.8%), amputation-free survival (87.1% vs 94.1%), and survival (92.3% vs 96.8%) (P < .001) at 1-year after PVI. Risk adjusted analysis showed that age ≥80 years was associated with higher reintervention/amputation/death (hazard ratio [HR], 1.22; 95% confidence interval [CI], 1.1-1.35), amputation/death (HR, 1.85; 95% CI, 1.61-2.13), and mortality (HR, 1.92; 95% CI, 1.66-2.23) (P < .001 for all) for PVI. For IIB, patients aged ≥80 years more often had an infrapopliteal target (28.4% vs 19.4%) and had higher 30-day mortality (1.3% vs 0.5%), renal failure (4.1% vs 2.2%), and cardiac complications (5.4% vs 3.1%) (P < .001). At 1 year, the age ≥80 years group had fewer independently ambulatory patients (81.7% vs 88.8%; P = .02). Kaplan-Meier analysis showed that the age ≥80 years cohort had lower reintervention/amputation-free survival (75.7% vs 81.5%), amputation-free survival (86.9% vs 93.9%), and survival (90.4% vs 96.5%) (P < .001 for all). Risk-adjusted analysis showed age ≥80 years was associated with higher amputation/death (HR, 1.68; 95% CI, 1.1-2.54; P = .015) and mortality (HR, 1.85; 95% CI, 1.16-2.93; P = .009), but not reintervention/amputation/death (HR, 1.1; 95% CI, 0.85-1.44; P = .47) after IIB. CONCLUSIONS: Octogenarians and nonagenarians have greater perioperative morbidity and long-term ambulatory impairment, limb loss, and mortality after PVI and IIB for claudication. Risks of intervention on elderly patients with claudication should be carefully weighed against the perceived benefits of revascularization. Medical and exercise therapy efforts should be maximized in this population.

Medial arterial calcification score is associated with increased risk of major limb amputation.

OBJECTIVE: The pedal medial arterial calcification (MAC) score has been associated with risk of major limb amputation in patients with chronic limb-threatening ischemia. This study aimed to validate the pedal MAC scoring system in a multi-institutional analysis to validate its usefulness in limb amputation risk prediction. METHODS: A multi-institution, retrospective study of patients who underwent endovascular or open surgical infrainguinal revascularization for chronic limb-threatening ischemia was performed. MAC scores of 0 to 5 were assigned based on visible calcified arteries on foot X ray then trichotomized (0-1, 2-4, 5) for analysis. The primary outcome was major limb amputation at 6 months. Adjusted Kaplan-Meier models were used to analyze time-to-major amputation across groups. RESULTS: There were 176 patients with 184 affected limbs (mean age, 66 years; 61% male; 60% White), of whom 97% presented with a wound. The MAC score was 0 in 41%, 1 in 9%, 2 in 13%, 3 in 11%, 4 in 13%, and 5 in 13% of the limbs. There were 26 major amputations (14%) and 16 deaths (8.7%) within 6 months. Patients with MAC 5 had a significantly higher risk of major limb amputation than both the 0 to 1 and 2 to 4 groups (P = .001 and P = .044, respectively), and lower overall amputation-free survival (log-rank P = .008). CONCLUSIONS: Pedal MAC score is a reproducible and generalizable measure of inframalleolar arterial disease that can be used with Wound, Ischemia, and foot Infection staging to predict major limb amputation in patients with chronic limb-threatening ischemia.

Area Deprivation Index is not predictive of worse outcomes after open lower extremity revascularization.

OBJECTIVE: Prior research has shown that socioeconomic status (SES) is associated with higher rates of diabetes, peripheral vascular disease, and amputation. We sought to determine whether SES or insurance type increases the risk of mortality, major adverse limb events (MALE), or hospital length of stay (LOS) after open lower extremity revascularization. METHODS: We conducted a retrospective analysis of patients who underwent open lower extremity revascularization at a single tertiary care center from January 2011 to March 2017 (n = 542). SES was determined using state Area Deprivation Index (ADI), a validated metric determined by income, education, employment, and housing quality by census block group. Patients undergoing amputation in this same time period (n = 243) were included to compare rates of revascularization to amputation by ADI and insurance status. For patients undergoing revascularization or amputation procedures on both limbs, each limb was treated individually for this analysis. We performed a multivariate analysis of the association between ADI and insurance type with mortality, MALE, and LOS using Cox proportional hazard models, including confounding variables such as age, gender, smoking status, body mass index, hyperlipidemia, hypertension, and diabetes. The cohort with an ADI quintile of 1, meaning least deprived, and the Medicare cohort were used for reference. P values of <.05 were considered statistically significant. RESULTS: We included 246 patients undergoing open lower extremity revascularization and 168 patients undergoing amputation. Controlling for age, gender, smoking status, body mass index, hyperlipidemia, hypertension, and diabetes, ADI was not an independent predictor of mortality (P = .838), MALE (P = .094), or hospital LOS (P = .912). Controlling for the same confounders, uninsured status was independently predictive of mortality (P = .033), but not MALE (P = .088) or hospital LOS (P = .125). There was no difference in the distribution of revascularizations or amputations by ADI (P = .628), but there was higher proportion of uninsured patients undergoing amputation compared with revascularization (P < .001). CONCLUSIONS: This study suggests that ADI is not associated with an increased risk of mortality or MALE in patients undergoing open lower extremity revascularization, but that uninsured patients are at higher risk of mortality after revascularization. These findings indicate that individuals undergoing open lower extremity revascularization at this single tertiary care teaching hospital received similar care, regardless of their ADI. Further study is warranted to understand the specific barriers that uninsured patients face.

Retrospective Review of Directional Atherectomy and Drug-Coated Balloon Use in a PAD Safety-Net Population.

BACKGROUND: Peripheral artery disease (PAD) is associated with high morbidity and mortality, particularly once patients develop critical limb threatening ischemia (CLTI). Minorities and vulnerable populations often present with CLTI and experience worse outcomes. The use of directional atherectomy (DA) and drug-coated balloon (DCB) during lower-extremity revascularization (LER) has not been previously described in a safety-net population. OBJECTIVE: To review demographic and clinical characteristics, and short- intermediate term outcomes of patients presenting to a safety-net hospital with PAD treated with DA and DCB during LER. METHODS: In this retrospective, observational cohort study, chart review was performed of all patients who underwent DA and DCB during LER for PAD from April 2016 to January 2020 in a safety-net hospital. RESULTS: The analysis included 58 patients, with 41% female, 24% Black/African American, and 31% Hispanic. From this group, 17% spoke a non-English primary language and 10% reported current or previous housing insecurity. Most (65%) presented with CLTI and had undergone a previous index leg LER (58%). The combination of DA and DCB was efficacious, resulting in low rates of bail-out stenting (16%) and target-vessel revascularization (26%) at 2 years. Low complication rates (tibial embolism in 12% and vessel perforation in 2% of cases) were also observed. Most patients (67%) with Rutherford category 5 experienced wound healing by 2 years. CONCLUSION: In this safety-net population, the majority presented with CLTI and a previous LER of the index leg. The combination of DA and DCB resulted in low complication rates, and good short-intermediate outcomes in this frequently undertreated population.

The outcomes of lower extremity revascularization: What role do race, ethnicity, and socioeconomic status play?

Lower extremity peripheral artery disease and the resultant complications disproportionately affect underrepresented racial and ethnic minority groups, as well as those with low socioeconomic status (SES). Revascularization, including both open surgical and endovascular techniques, is a mainstay of therapy for symptomatic peripheral artery disease; it is required to maximize limb salvage in chronic limb-threatening ischemia and used to improve function and quality of life in patients with claudication. The outcomes of lower extremity revascularization in Black and Hispanic patients, as well as patients with low SES, are not widely known and this knowledge gap formed the basis for this review. The preponderance of evidence suggests that Black, Hispanic, and low-SES patients have inferior limb-related outcomes after revascularization compared with White patients. Based solely on the limited published evidence in the revascularization literature, the specific reasons for these disparities are not clear. The high prevalence of comorbidities and risks factors, as well as the advanced presentation of peripheral artery disease in Black, Hispanic, and low-SES patients, appear to contribute to the inferior limb outcomes post revascularization seen in these groups, but do not account for all of the disparities. Undoubtedly, a complex interplay of social determinants underlies these disparities in care and outcomes at individual, community, and societal levels. Additional understanding of the underpinnings and mechanisms of inferior outcomes in these populations in the specific context of lower extremity revascularization is needed, as this would allow us to identify targets for intervention to improve post-revascularization outcomes in these at-risk populations.

Predictors of poor outcomes after lower extremity revascularization for acute limb ischemia.

OBJECTIVES: Acute lower extremity ischemia is one of the most common emergencies in vascular surgery and is a cause of considerable morbidity and mortality. The goal of this study was to evaluate outcomes of revascularization for acute lower extremity ischemia and to determine factors associated with perioperative morbidity and mortality. METHODS: A total of 354 patients underwent urgent revascularization for acute lower extremity ischemia at an academic medical center between 2014 and 2019. A retrospective review of patients' demographics, comorbidities, etiology and severity of limb ischemia, and procedural characteristics was recorded. Outcomes, including postoperative complications, perioperative limb loss, and mortality, were analyzed. RESULTS: The mean patient age was 69 ± 17 years, and 52% were females. 50% of patients presented with Rutherford Class IIb ischemia. Arterial embolization was the most common cause of limb ischemia, seen in 33% of cases. Open surgical revascularization was performed in 241 (68%) patients, while endovascular and hybrid approaches were utilized in 53 (15%) and 60 (17%) cases, respectively. Postoperative adverse events occurred in 44% of patients, including wound complications (11%), cardiac (5%) and pulmonary (16%) complications, strokes (4%), UTIs (10%), renal failure (14%), bleeding (5%), and compartment syndrome (3%). The rate of unplanned return to the operating room was 21%. Major adverse cardiovascular events were seen in 103 (29%) patients and major adverse limb events were seen in 57 (16%) patients. The median length of stay was 10 days (IQR = 4); 49% patients were discharged to skilled nursing facility and 19% were readmitted within 30 days.The rate of amputation during index admission was 10%, and perioperative mortality was 20%. Gender, tibial runoff, and etiology of limb ischemia were independent predictors of limb loss. Women had lower risk of limb loss than men (OR, 0.11; 95% CI, 0.023, 0.38). Poor tibial runoff (one-vessel or absence of flow below the knee) was a significant predictor of limb loss as compared to three-vessel runoff (OR, 14.92; 95% CI, 1.92, 115.88). Aneurysmal disease (OR, 38.35; 95% CI, 3.54, 42.45) and traumatic injuries (OR, 108.08; 95% CI, 8.21, 159.06) were the strongest predictors of amputation as compared to other etiologies of limb ischemia. Multivariate model identified ESRD (OR, 9.2; 95% CI, 1.8-46.3), degree of ischemia (class IIb or higher vs class IIa; OR, 3.5; 95% CI, 1.2-10.6), and age (OR, 1.5; 95% CI 1.1-2.0 for every 10 years) as independent predictors of perioperative mortality. CONCLUSIONS: Urgent revascularization for management of acute limb ischemia is associated with high morbidity and mortality. Elderly patients with ESRD presenting with severely threatened limbs have especially high risk of perioperative mortality and may not be ideal candidates for limb salvage.

Open Proximal Endarterectomy with Retrograde Access and Stenting: A Novel Technique for Lower Extremity Revascularization.

BACKGROUND: Treatment of chronic limb threatening ischemia (CLTI) poses a significant clinical challenge despite recent medical advancements. Chronic total occlusion (CTO) lesions make endovascular approaches to CLTI particularly challenging. Open proximal exposure with retrograde access and stenting (OPERAS) aims to solve this challenge through retrograde subintimal crossing of a CTO with direct visualization of proximal re-entry into the true lumen. We describe this novel technique and present its efficacy in eight patients. METHODS: We conducted a retrospective case series at a single tertiary academic center. Data for patients who received OPERAS intervention included demographics, peri-operative details, and follow-up information. Statistical analysis was performed on length of stay, major post-operative complications, further intervention, clinical progression at 1 year, and amputation-free survival at 1 year. Immediate technical failure (ITF) and limb-based patency (LBP) at 1 year were calculated. RESULTS: Nine limbs underwent OPERAS between January 2019 and March 2020. Inflow was achieved with common femoral artery endarterectomy. All limbs underwent balloon angioplasty and stenting of the SFA, and seven underwent the same procedure in the popliteal artery. ITF was 0% for all nine cases. There were no major post-operative complications, and ankle-brachial index significantly improved pre-and post-operatively (P < .001). Eight limbs (88.9%) sustained amputation-free survival at 1 year, and overall LBP was 67% at 1 year. CONCLUSION: Our study presents a hybrid revascularization option to address severe, anatomically complex limbs (GLASS III) that lack a single autogenous conduit for open surgical revascularization. OPERAS addresses a main point of technical failure of subintimal techniques by directly visualizing the wire in the true lumen. Our data suggest that OPERAS can be effective to: (1) improve technical success of luminal re-entry following a subintimal approach; (2) address inflow concurrently with severe femoropopliteal disease; and (3) can be utilized when distal tissue loss is involved.

Combined Prognostic Value of Preprocedural Protein-Energy Wasting and Inflammation Status for Amputation and/or Mortality after Lower-Extremity Revascularization in Hemodialysis Patients with Peripheral Arterial Disease.

Protein-energy wasting is associated with inflammation and advanced atherosclerosis in hemodialysis patients. We enrolled 800 patients who had undergone successful lower-extremity revascularization, and we investigated the association among the Geriatric Nutritional Risk Index (GNRI) as a surrogate marker of protein-energy wasting, C-reactive protein (CRP), and their joint roles in predicting amputation and mortality. They were divided into lower, middle, and upper tertiles (T1, T2, and T3) according to GNRI and CRP levels, respectively. Regarding the results, the amputation-free survival rates over 8 years were 47.0%, 56.9%, and 69.5% in T1, T2, and T3 of the GNRI and 65.8%, 58.7%, and 33.2% for T1, T2, and T3 of CRP, respectively (p < 0.0001 for both). A reduced GNRI [adjusted hazard ratio (aHR) 1.78, 95% confidence interval (CI) 1.24-2.59, p = 0.0016 for T1 vs. T3] and elevated CRP (aHR 1.86, 95% CI 1.30-2.70, p = 0.0007 for T3 vs. T1) independently predicted amputation and/or mortality. When the two variables were combined, the risk was 3.77-fold higher (95% CI 1.97-7.69, p < 0.0001) in patients who occupied both T1 of the GNRI and T3 of CRP than in those who occupied both T3 of the GNRI and T1 of CRP. In conclusion, patients with preprocedurally decreased GNRI and elevated CRP levels frequently experienced amputation and mortality, and a combination of these two variables could more accurately stratify the risk.