Incidence and Factors Associated With Major Amputation in Patients With Peripheral Artery Disease

Outcomes of drug-coated balloon angioplasty in patients with dyslipidemia in the BIOLUX P-III registry: A subgroup analysis

OBJECTIVES

The aim of this study was to assess the mid-term outcomes of the use of drug-coated balloons (DCBs) to treat infrainguinal peripheral arterial disease (PAD) in patients with dyslipidemia.

METHODS

BIOLUX P-III is a prospective, international, multicenter, all-comers registry-based study that was conducted at 44 sites with follow-ups at 6, 12 and 24 months. The present study is a subgroup analysis comparing the outcomes associated with endovascular revascularization with those associated with Passeo-18 lux DCBs in patients with and without dyslipidemia. The proportions of patients free from major adverse events (defined as device- or procedure-related mortality within 30 days, clinically driven target lesion revascularization (CD-TLR) and major target limb amputation), target vessel revascularization, and patient-reported outcomes within 24 months postintervention were compared between the two groups.

RESULTS

A total of 876 patients with symptomatic PAD who underwent peripheral revascularization with DCBs and had information on their dyslipidemia status were included; 588 of those patients had dyslipidemia. There was no difference in the proportion of patients free from MAEs between the groups. The percentages of patients who were 6, 12 and 24 months free from CD-TLR were significantly lower in the dyslipidemia group than in the nondyslipidemia group (86.3% vs 91.9% at 2 years, p = .0183). Similarly, the percentage of patients free from target vessel revascularization was lower in the dyslipidemia group at all timepoints (83.3% vs 89.3% at 2 years, p = .0203). There was no difference in mortality or major or minor limb amputation rates. Other secondary outcomes were similar between the groups.

CONCLUSIONS

Compared to those without dyslipidemia, patients with symptomatic PAD and dyslipidemia who underwent revascularization with a Passeo-18 lux DCB had greater rates of CD-TLR and TVR. However, having dyslipidemia did not increase the risk of mortality or limb amputation.

CLINICAL TRIAL REGISTRATION

NCT02276313.

Factors associated with 90-day reintervention following lower extremity revascularization

OBJECTIVE

Peripheral artery disease (PAD) represents a high-volume, high-cost burden on the health care system. The Centers for Medicare and Medicaid Services has developed the Bundled Payments for Care Improvement-Advanced program, in which a single payment is provided for all services administered in a postsurgical 90-day episode of care. Factors associated with 30- and 90-day reinterventions after PAD interventions would represent useful data for both payors and stake holders.

METHODS

We conducted a national cohort study of adults 65 years and older in the Vascular Quality Initiative and Centers for Medicare and Medicaid Services-linked dataset who underwent an open, endovascular, or hybrid revascularization procedure for PAD between January 1, 2010, and December 31, 2018. Procedures for acute limb ischemia and aneurysms were excluded. The primary outcome was 90-day reintervention. Reintervention at 30 days was a secondary outcome. Covariates of interest included demographics, comorbidities, and patient- and facility-level characteristics. Multivariable Cox regression was used to determine the association between patient- and facility-level characteristics and the risk of 30- and 90-day reinterventions.

RESULTS

Among 42,429 patients (71.3% endovascular, 23.3% open, and 5.4% hybrid), median age was 74 years (interquartile range, 69-80 years), 57.9% were male, and 84.3% were White. Chronic limb-threatening ischemia was the operative indication in 40.4% of the procedures. Overall, 42.8% were completed in the outpatient setting (40.3% outpatient, 2.5% office-based lab). Over 70% of procedures for chronic limb-threatening ischemia were completed as inpatient, whereas 60% of the claudication interventions were done as outpatient. The 90-day reintervention rate was 14.5%, and the 30-day reintervention rate was 5.5%. Compared with inpatient procedures, PAD interventions completed in the outpatient or office-based lab setting had significantly higher 90- and 30-day reintervention rates (reference, inpatient; outpatient 90-day reintervention: hazard ratio [HR], 1.41; 95% confidence interval [CI] 1.25-1.60; outpatient 30-day reintervention: HR, 1.90; 95% CI, 1.62-2.24; office-based lab 90-day reintervention: HR, 2.09; 95% CI, 1.82-2.41; office-based lab 30-day reintervention: HR, 3.54; 95% CI, 3.17-3.94). Open and hybrid approaches demonstrated lower risk of reintervention compared with endovascular procedures at 30 and 90 days and, compared with aortoiliac disease, all other anatomic segments of disease were associated with higher 90-day reintervention, but no difference was noted at 30 days.

CONCLUSIONS

Although outpatient PAD interventions may be convenient for patients and providers, the outpatient setting is associated with a significant risk of subsequent reintervention. Additional work is needed to understand how to improve the longevity of outpatient PAD interventions.

Risk of Heart Disease in Patients With Amputation: A Nationwide Cohort Study in South Korea

BACKGROUND

Amputation confers disabilities upon patients and is linked to substantial morbidity and death attributed to heart disease. While some studies have focused on traumatic amputees in veterans, few studies have focused on traumatic amputees within the general population. Therefore, the present study aimed to assess the risk of heart disease in patients with traumatic amputation with disability within the general population using a large-scale nationwide population-based cohort.

METHODS AND RESULTS

We used data from the Korean National Health Insurance System. A total of 22 950 participants with amputation were selected with 1:3 age, sex-matched controls between 2010 and 2018. We used Cox proportional hazard models to calculate the risk of myocardial infarction, heart failure, and atrial fibrillation among amputees. Participants with amputation had a higher risk of myocardial infarction (adjusted hazard ratio [aHR], 1.30 [95% CI, 1.14-1.47]), heart failure (aHR, 1.27 [95% CI, 1.17-1.38]), and atrial fibrillation (aHR, 1.17 [95% CI, 1.03-1.33]). The risks of myocardial infarction and heart failure were further increased by the presence of disability (aHR, 1.43 [95% CI, 1.04-1.95]; and aHR, 1.38 [95% CI, 1.13-1.67], respectively).

CONCLUSIONS

We demonstrate an increased risk of myocardial infarction, heart failure, and atrial fibrillation among individuals with amputation, and the risk further increased in those with disabilities. Clinicians should pay attention to the increased risk for heart disease in patients with amputation.

Association Between the Society for Vascular Surgery (SVS)-WIfI (Wound, Ischemia, Foot Infection) Classification, Wagner-Meggitt Classification, and Amputation Rate in Patients With Diabetic Foot Infection

Diabetic foot infection (DFI) is a common problem in patients with diabetic foot disease. Amputations and other complications of DFI lead to significant morbidity and mortality. The Society for Vascular Surgery (SVS)-WIfI (wound, ischemia, and foot infection) classification system can evaluate the benefit from revascularization and the risk of amputation in 1 and 3 years. We aimed to evaluate SVS-WIfI and Wagner-Meggitt (WM) prediction of DFI outcome, and to determine factors associated with major amputation and mortality rate. The patients with diabetes who presented between June 2018 and May 2020 with characteristics suggesting a more serious DFI or potential indications for hospitalization were reviewed in this cohort study. Demographic data, clinical characteristics, and type of revascularization were evaluated. One-year and 3-year amputation and mortality rates were the main outcomes. The grading of WM classification and the SVS-WIfI score were compared between amputation and nonamputation groups. Association between mortality and comorbidity were analyzed. One hundred and thirty-one patients admitted with DFI were included in study. And 73.28% had peripheral arterial disease (PAD). The 1-year and 3-year major amputation rates were 16.03% and 26.23%, respectively. Seventy-eight (59.54%) patients required minor amputation to control infection before revascularization. PAD (risk ratio [RR] 1.47: 95% confidence interval [CI] 1.29-1.67, P = .032), benefit from revascularization clinical stage 3 on SVS-WIfI score (RR 4.56: 95%CI 1.21-17.21, P = 0.007), and high WM classification score (RR 9.46: 95% CI 5.65-15.82, P < 0.001) were associated by multivariate analysis with high amputation rates. 1-year & 3-year amputation risk on SVS-WIfI score were not associated with amputation rates in DFI (P = .263 and .496). Only 9 (6.8%) patients were lost to follow up during the 3-year period. WM classification score, SVS-WIfI score on benefit from revascularization, and PAD were strongly associated with major amputation rates in patients with DFI.

Rivaroxaban Plus Aspirin Versus Aspirin Alone After Endovascular Revascularization for Symptomatic PAD: Insights From VOYAGER PAD

BACKGROUND

Rivaroxaban plus aspirin compared with aspirin alone reduced major cardiac and ischemic limb events after lower extremity revascularization (LER) in the VOYAGER PAD (Vascular Outcomes Study of ASA Along With Rivaroxaban in Endovascular or Surgical Limb Revascularization for Peripheral Artery Disease) trial. The effect has not been described in patients undergoing endovascular LER.

METHODS

The VOYAGER PAD trial randomized 6564 patients with symptomatic peripheral artery disease to a double-blinded treatment with 2.5 mg of rivaroxaban BID or matching placebo and 100 mg of aspirin daily. The primary efficacy outcome was a composite of acute limb ischemia, major amputation of a vascular pathogenesis, myocardial infarction, ischemic stroke, or cardiovascular death. The principal safety end point was Thrombolysis in Myocardial Infarction major bleeding. A prespecified subgroup of patients who underwent endovascular revascularization was included.

RESULTS

Endovascular LER occurred in 4379 (66.7%) patients and surgical LER in 2185 (33.3%). Over a 3-year follow-up, rivaroxaban reduced the risk of the primary outcome by 15% (hazard ratio [HR], 0.85 [95% CI, 0.76-0.96]) with an absolute risk reduction of 0.92% at 6 months and 1.04% at 3 years and a consistent benefit in those receiving endovascular (HR, 0.89 [95% CI, 0.76-1.03]) or surgical LER (HR, 0.81 [95% CI, 0.67-0.98]; P interaction=0.43). For endovascular-treated patients, rivaroxaban reduced the risk of acute limb ischemia or major amputation of a vascular pathogenesis by 30% (HR, 0.70 [95% CI, 0.54-0.90]; P=0.005) with an absolute risk reduction of 1.0% at 6 months and 2.0% at 3 years compared with aspirin alone. Among endovascular-treated patients, the median duration of concomitant dual antiplatelet therapy with clopidogrel treatment was 31 days (interquartile range, 30-58). There was a consistent benefit for rivaroxaban regardless of background clopidogrel. Thrombolysis in Myocardial Infarction major bleeding was significantly higher for the rivaroxaban and aspirin group for the endovascular cohort (HR, 1.66 [95% CI, 1.06-2.59]) with an absolute risk increase of 0.9% at 3 years with no increase in intracranial or fatal bleeding observed (HR, 0.86 [95% CI, 0.40-1.87]; P=0.71). Mortality with rivaroxaban was higher in the endovascular-treated patients (HR, 1.24 [95% CI, 1.02-1.52]), although this finding was isolated to specific regions.

CONCLUSIONS

Rivaroxaban added to aspirin or dual antiplatelet therapy after LER for peripheral artery disease reduces ischemic risk and increases major bleeding without an increased risk of intracranial or fatal bleeding. These benefits are consistent in those treated with endovascular and surgical approaches with significant benefits for major adverse limb events. These data support the use of rivaroxaban in addition to aspirin or dual antiplatelet therapy after endovascular intervention for symptomatic peripheral artery disease.

Ultrasound-Guided peripheral nerve blocks for major amputation in critically ill patients with peripheral artery disease

OBJECTIVE

The aim of this study was to assess the safety and efficacy of major amputation under ultrasound-guided peripheral nerve blocks in critical peripheral artery disease (PAD) patients.

METHODS

We reviewed the medical records of consecutive patients who underwent major amputation at our center between December 2012 and December 2020. The patients' baseline demographics and comorbidities were collected. The primary outcomes were 30-day and 12-month mortality. The secondary outcomes were intraoperative events, complications and intensive care unit (ICU) admission.

RESULTS

Fifteen patients classified as American Society of Anesthesiologist (ASA) III and 13 ASA IV (mean age: 76.07 ± 11.78 years) were included in the study. These patients were critically ill and had many comorbidities, such as coronary artery disease. All amputations were successfully performed under ultrasound-guided PNB without conversion to GA, but intravenous analgesia was given in 7 patients during the operation. The majority of the patients had stable hemodynamics except for 2 patients who had hypoxia, so none of the patients were transferred to the ICU postoperatively. None of the patients suffered from acute cardio-cerebral events. However, 5 patients had wound infections, and 4 of 5 patients had to receive reamputation. None of the patients died within 48 h after amputation. However, the 30-day mortality was 3.57%, and the 12-month mortality was up to 35.71%.

CONCLUSION

This study demonstrates that major amputation could be safely and effectively performed under ultrasound-guided peripheral nerve blocks for critically ill patients, and ultrasound-guided peripheral nerve blocks could be an alternative for patients at high risk of general anesthesia or spinal anesthesia.

Preventive Therapies in Peripheral Arterial Disease

Atherosclerosis, while initially deemed a bland proliferative process, is now recognized as a multifactorial-lipoprotein-mediated inflammation-driven pathway. With the rising incidence of atherosclerotic disease of the lower extremity arteries, the healthcare burden and clinical morbidity and mortality due to peripheral artery disease (PAD) are currently escalating. With a healthcare cost burden of over 21 billion USD and 200 million patients afflicted worldwide, accurate knowledge regarding the pathophysiology, presentation, and diagnosis of the disease is crucial. The role of lipoproteins and their remnants in atherosclerotic vessel occlusion and plaque formation and progression has been long established. This review paper discusses the epidemiology, pathophysiology, and presentation of PAD. PAD has been repeatedly noted to portend to poor cardiovascular and limb outcomes. We discuss major therapeutic avenues for the prevention of major cardiovascular adverse events and major limb adverse events in patients with PAD.

Cost-Effectiveness of Glucose-Lowering Therapies as Add-on to Standard Care for People With Type 2 Diabetes in Malaysia

OBJECTIVES

This study aims to evaluate the cost-effectiveness of various glucose-lowering therapies as add-on to standard care for people with type 2 diabetes (T2D) in Malaysia.

METHODS

A state-transition microsimulation model was developed to compare the clinical and economic outcomes of 4 treatments: standard care, dipeptidyl peptidase-4 inhibitors, sodium-glucose cotransporter-2 inhibitors (SGLT2is), and glucagon-like peptide-1 receptor agonists. Cost-effectiveness was assessed from a healthcare provider's perspective over a lifetime horizon with 3% discount rate in a hypothetical cohort of people with T2D. Data input were informed from literature and local data when available. Outcome measures include costs, quality-adjusted life-years, incremental cost-effectiveness ratios, and net monetary benefits. Univariate and probabilistic sensitivity analyses were performed to assess uncertainties.

RESULTS

Over a lifetime horizon, the costs to treat a person with T2D ranged from RM 12 494 to RM 41 250, whereas the QALYs gains ranged from 6.155 to 6.731, depending on the treatment. Based upon a willingness-to-pay threshold of RM 29 080 per QALY, we identified SGLT2i as the most cost-effective glucose-lowering treatment, as add-on to standard care over patient's lifetime, with the net monetary benefit of RM 176 173 and incremental cost-effectiveness ratios of RM 12 279 per QALY gained. The intervention also added 0.577 QALYs and 0.809 LYs compared with standard care. Cost-effectiveness acceptability curve showed that SGLT2i had the highest probability of being cost-effective in Malaysia across varying willingness-to-pay threshold. The results were robust to various sensitivity analyses.

CONCLUSIONS

SGLT2i was found to be the most cost-effective intervention to mitigate diabetes-related complications.

Analysis of Lower Extremity Amputations from the SerbVasc Registry

BACKGROUND

Peripheral arterial disease (PAD) and diabetes are the major causes of lower extremity amputations (LEAs) worldwide. Morbidity and mortality in patients with LEAs are high with an associated significant burden on the global health system. The aim of this article is to report the overall morbidity and mortality rates after major and minor LEAs from the Serbian Vascular Registry (SerbVasc), with an analysis of predictive factors that influenced adverse outcomes.

MATERIALS AND METHODS

SerbVasc was created in 2019 as a part of the Vascunet collaboration that is aiming to include all vascular procedures from 21 hospitals in Serbia. Prevalence of diabetes among patients with LEAs, previous revascularization procedures, the degree and the type of foot infection and tissue loss, and overall morbidity and mortality rates were analyzed, with a special reference to mortality predictors.

RESULTS

In the period from January 2020 to December 2022, data on 702 patients with LEAs were extracted from the SerbVasc registry, mean age of 69.06±10.63 years. Major LEAs were performed in 59%, while minor LEAs in 41% of patients. Diabetes was seen in 65.1% of the patients, with 44% of them being on insulin therapy. Before LEA, only 20.3% of patients had previous peripheral revascularization. Soft tissue infection, irreversible acute ischemia, and Fontaine III and IV grade ischemia were the most common causes of above-the-knee amputations while diabetic foot was the most common cause of transphalangeal and toe amputations. The infection rate was 3.7%, the re-amputation rate was 5.7%, and the overall mortality rate was 6.9%, with intrahospital mortality in patients with above-the-knee amputation of 11.1%. The most significant intrahospital mortality predictors were age >65 years (p<0.001), chronic kidney disease (CKD) (p<0.001), ischemic heart disease (IHD) (p=0.001), previous myocardial revascularization (p=0.017), emergency type of admission (p<0.001), not using aspirin (p=0.041), using previous anticoagulation therapy (p=0.003), and postoperative complications (p<0.001).

CONCLUSIONS

The main predictors of increased mortality after LEAs from the SerbVasc registry are age >65 years, CKD, IHD, previous myocardial revascularization, emergency type of admission, not using aspirin, using previous anticoagulation therapy, and postoperative complications. Taking into account high mortality rates after LEAs and a small proportion of previous peripheral revascularization, the work should be done on early diagnosis and timely treatment of PAD hopefully leading to decreased number of LEAs and overall mortality.

CLINICAL IMPACT

Mortality after lower limb amputation from the SerbVasc register is high. A small number of previously revascularized patients is of particular clinical importance, bearing in mind that the main reasons for above-the-knee amputations were irreversible ischemia, Fontaine III and Fontaine IV grade ischemia. Lack of diagnostics procedures and late recognition of patients with PAD, led to subsequent threating limb ischemia and increased amputation rates. The work should be done on early diagnosis and timely treatment of PAD in Serbia, hopefully leading to an increased number of PAD procedures, decreased number of LEAs, and lower overall mortality.

Risk Factors for Lower Extremity Amputation in Patients with End-Stage Kidney Disease: A Nationwide Cohort Study

Individuals with end-stage kidney disease (ESKD) on dialysis are at a high risk of developing foot ulcerations and undergoing subsequent lower extremity amputation (LEA), which can exert significant impacts on their quality of life and contribute to rising healthcare costs. We aimed to identify risk factors associated with LEA in patients with ESKD to predict LEA progression and eventually prevent it. We used 18 years (2002-2019) of data from the Korean National Health Insurance Service (KNHIS). Data were collected from patients with ESKD who underwent renal replacement therapy (RRT) and had no history of amputation caused by trauma or toxins. The risk factors were compared between patients with or without LEA. We collected data from 220,838 patients newly diagnosed with ESKD, including 6348 in the LEA group and 214,490 in the non-LEA group. The total incidence of LEA was 2.9%. Older age, male gender, lower income, non-metropolitan residence, diabetes mellitus, dialysis treatment (compared to kidney transplantation), microvascular disease, peripheral vascular disease, endovascular procedure, and endovascular operation were associated with an increased risk of LEA. Thus, individuals with ESKD who are at a higher risk for LEA should be closely monitored, and kidney transplantation should be considered as a preventative measure.

Association of Health Care Utilization and Access to Care With Vascular Assessment Before Major Lower Extremity Amputation Among US Veterans

Importance

Patient-level characteristics alone do not account for variation in care among US veterans with peripheral artery disease (PAD). Presently, the extent to which health care utilization and regional practice variation are associated with veterans receiving vascular assessment prior to major lower extremity amputation (LEA) is unknown.

Objective

To assess whether demographics, comorbidities, distance to primary care, the number of ambulatory clinic visits (primary and medical specialty care), and geographic region are associated with receipt of vascular assessment prior to LEA.

Design, Setting, and Participants

This national cohort study used US Department of Veterans Affairs' Corporate Data Warehouse data from March 1, 2010, to February 28, 2020, for veterans aged 18 or older who underwent major LEA and who received care at Veterans Affairs facilities.

Exposures

The number of ambulatory clinic visits (primary and medical specialty care) in the year prior to LEA, geographic region of residence, and distance to primary care.

Main Outcomes and Measures

The main outcome was receipt of a vascular assessment (vascular imaging study or revascularization procedure) in the year prior to LEA.

Results

Among 19 396 veterans, the mean (SD) age was 66.78 (10.20) years and 98.5% were male. In the year prior to LEA, 8.0% had no primary care visits and 30.1% did not have a vascular assessment. Compared with veterans with 4 to 11 primary care clinic visits, those with fewer visits were less likely to receive vascular assessment in the year prior to LEA (1-3 visits: adjusted odds ratio [aOR], 0.90; 95% CI, 0.82-0.99). Compared with veterans who lived less than 13 miles from the closest primary care facility, those who lived 13 miles or more from the facility were less likely to receive vascular assessment (aOR, 0.88; 95% CI, 0.80-0.95). Veterans who resided in the Midwest were most likely to undergo vascular assessment in the year prior to LEA than were those living in other regions.

Conclusions and Relevance

In this cohort study, health care utilization, distance to primary care, and geographic region were associated with intensity of PAD treatment before LEA, suggesting that some veterans may be at greater risk of suboptimal PAD care practices. Development of clinical programs, such as remote patient monitoring and management, may represent potential opportunities to improve limb preservation rates and the overall quality of vascular care for veterans.

Amputation in diabetic foot ulcer: A treatment dilemma

Diabetic foot is a clinical manifestation of diabetes with a wide range of symptoms, including ulceration, osteomyelitis, osteoarticular destruction, and gangrene, as a consequence of advanced disease. Some diabetic foot cases present general indications for amputation, including dead limb, threat to the patient’s life, pain, loss of function, or nuisance. Various tools have been introduced to help decision-making in amputation for diabetic foot. However, it remains a conundrum because diabetic foot involves multiple pathomechanisms and factors that hinder its outcomes. Sociocultural issues often impede treatment from the patient’s side. We reviewed different perspectives in diabetic foot management, particularly related to amputation. In addition to deciding whether to amputate, physicians should address amputation level, timing, and ways to avoid patient deconditioning. Surgeons should not be autocratic in these circumstances and should be aware of beneficence and maleficence when considering whether to amputate. The main goal should be improving the patients’ quality of life rather than preserving the limb as much as possible.

Cost-effectiveness analysis of screening for peripheral artery disease in patients with coronary artery disease in China: A Markov model

BACKGROUND

The innovative pharmacological combination of low-dose rivaroxaban plus aspirin provides clinicians with an ideal opportunity to intensify the medical treatment of patients with coronary artery disease (CAD) and comorbid peripheral artery disease (PAD). We aimed to determine the cost-effectiveness of PAD screening using the ankle-brachial index (ABI) test in patients with CAD (with rivaroxaban administered if the PAD screening was positive) compared with no-screening strategy in China.

METHODS

A Markov decision model using a 1-month cycle was developed to simulate the 25-year effectiveness and cost of PAD screening on 75-year-old patients with CAD in China, evaluating the quality-adjusted life years (QALYs) and incremental cost-effectiveness ratio (ICER). One-way, two-way, and probabilistic sensitivity analyses were conducted to assess the impact of variations in the key parameters for ICERs.

RESULTS

Our model found an incremental cost of RMB4,959 (US$740) and an incremental QALY of 0.054 after one-time ABI screening, leading to an ICER of RMB91,936 (US$13,717) per QALY gained over a 25-year period. The reduction in all-cause mortality related to rivaroxaban and its cost were the factors most affecting the ICER. The screening would become cost-effective by decreasing the monthly cost of rivaroxaban to RMB184.5 (US$27.5) or by using domestic-brand rivaroxaban according to the threshold of a willingness to pay RMB72,447 (US$10,809) per QALY gained.

CONCLUSIONS

Our study demonstrated that ABI screening for PAD to decide on low-dose rivaroxaban administration was not cost-effective for patients with CAD in China. Nevertheless, policy-guided cost changes for domestic-brand rivaroxaban could easily resolve this issue.

Role of Lipid-Lowering Therapy in Peripheral Artery Disease

Atherosclerosis is a multifactorial, lipoprotein-driven condition that leads to plaque formation within the arterial tree, leading to subsequent arterial stenosis and thrombosis that accounts for a large burden of cardiovascular morbidity and mortality globally. Atherosclerosis of the lower extremities is called peripheral artery disease and is a major cause of loss in mobility, amputation, and critical limb ischemia. Peripheral artery disease is a common condition with a gamut of clinical manifestations that affects an estimated 10 million people in the United States of America and 200 million people worldwide. The role of apolipoprotein B-containing lipoproteins, such as LDL and remnant lipoproteins in the development and progression of atherosclerosis, is well-established. The focus of this paper is to review existing data on lipid-lowering therapies in lower extremity atherosclerotic peripheral artery disease.

Neutrophil-to-Lymphocyte Ratio as a Predictive Tool for Post-Operative Outcomes in Patients Undergoing Open Lower Extremity Revascularization Procedures

INTRODUCTION

Elevated neutrophil-to-lymphocyte ratio (NLR), a marker of systemic inflammation, has been shown to correlate with worse outcomes in patients undergoing vascular surgery. Limited data exists on the association of NLR and outcomes in patients undergoing lower extremity vascular surgery. We sought to investigate whether preoperative NLR correlates with outcomes in patients undergoing open lower extremity revascularization procedures.

METHODS

We conducted a retrospective analysis of a prospectively maintained database of patients who underwent open lower extremity revascularization procedures from January 2011 to January 2017 (N=535). Preoperative NLR was calculated within six months of surgery. Primary outcomes were major adverse limb event (MALE) or death. The maximally-ranked statistic method was used to determine the NLR cut-off point. Kaplan-Meier analyses of death and MALE and NLR were used to compare the groups by NLR cut-off point. We conducted a multivariate analysis of the association between NLR and mortality using Cox proportional hazard models, including confounding variables such as age, smoking status, and diabetes. P-values <0.05 were considered statistically significant.

RESULTS

254 patients undergoing surgery from January 2011 to January 2013 were analyzed. The median NLR was 3.6 [IQR 2.5 - 6.7]. The analysis showed a negative correlation between elevated NLR and mortality (P<0.001), but not MALE (P=0.8). Controlling for multiple comorbidities including gender, age, smoking, BMI, diabetes, hyperlipidemia, hypertension, and infection, the NLR cut-off point was a significant independent predictor of mortality (P<0.0001), but not MALE (P=0.551). Elevated NLR was also correlated with statistically and clinically significant longer hospital stays (6.5 [IQR 3.0 - 12.8] days vs. 4.0 [IQR 2.0 - 8.0] days, P=0.027).

CONCLUSION

This study suggests that NLR is an independent predictor of mortality and hospital length of stay in patients undergoing open lower extremity revascularizations. Going forward, we plan to expand this study to include more patients and to compare NLR to other risk assessment tools.

Statins and statin intensity in peripheral artery disease

Background: Peripheral artery disease (PAD) affects more than 202 million people worldwide. Several studies have shown that patients with PAD are often undertreated, and that statin utilization is suboptimal. European and American guidelines highlight statins as the first-line lipid-lowering therapy to treat patients with PAD. Our objective with this meta-analysis was to further explore the impact of statins on lower extremities PAD endpoints and examine whether statin dose (high vs. low intensity) impacts outcomes. Patients and methods: We performed a systematic review and meta-analysis according to the PRISMA guidelines. Any study that presented a comparison of use of statins vs. no statins for PAD patients or studies comparing high vs. low intensity statins were considered to be potentially eligible. We excluded studies with only critical limb threatening ischemia (CLTI) patients. The Medline (PubMed) database was searched up to January 31, 2021. A random effects meta-analysis was performed. Results: In total, 39 studies and 275,670 patients were included in this meta-analysis. In total, 136,025 (49.34%) patients were on statins vs. 139,645 (50.66%) who were not on statins. Statin use was associated with a reduction in all cause-mortality by 42% (HR: 0.58, 95% CI: 0.49-0.67, p<0.01) and cardiovascular death by 43% (HR: 0.57, 95% CI: 0.40-0.74, p<0.01). Statin use was associated with an increase in amputation-free survival by 56% (HR: 0.44, 95% CI: 0.30-0.58, p<0.01). The risk of amputation and loss of patency were reduced by 35% (HR: 0.65, 95% CI: 0.41-0.89, p<0.01) and 46% (HR: 0.54, 95% CI: 0.34-0.74, p<0.01), respectively. Statin use was also associated with a reduction in the risk of major adverse cardiovascular events (MACE) by 35% (HR: 0.65, 95% CI: 0.51-0.80, p<0.01) and myocardial infarction rates by 41% (HR: 0.59, 95% CI: 0.33-0.86, p<0.01). Among patients treated with statins, the high-intensity treatment group was associated with a reduction in all cause-mortality by 36% (HR: 0.64, 95% CI: 0.54-0.74, p<0.01) compared to patients treated with low intensity statins. Conclusions: Statin treatment among patients with PAD was associated with a statistically significant reduction in all-cause mortality, cardiovascular mortality, MACE, risk for amputation, or loss of patency. Higher statin dose seems to be associated with improved outcomes.

Comorbid Depression is Associated with Increased Major Adverse Limb Events in Peripheral Arterial Disease: A systematic review and meta-analysis

OBJECTIVE

Depression is a significant risk factor for mortality in coronary artery disease. On the contrary, the research surrounding depression and peripheral arterial disease is limited. This review aims to systematically evaluate the available literature on the impact of comorbid depression on adverse outcomes in peripheral arterial disease.

DATA SOURCES

A systematic review and meta-analysis were performed using the following databases: MEDLINE, EMBASE, CINAHL, PsycINFO, and Cochrane Library from inception until July 2021.

REVIEW METHODS

Included studies compared depressed and non-depressed patients with peripheral arterial disease. The outcomes included mortality, major adverse cardiovascular events, and major adverse limb events.

RESULTS

A total of 9 297 articles were searched. Of these, seven studies were identified. Depressed patients were more likely to be women, be diabetic, have a history of smoking, and have chronic limb threatening ischemia, despite being younger than non-depressed patients. There was a 20% increase in major adverse limb events in depressed patients [RR 1.20, 95% CI (1.11 - 1.31), z =3.9, p<.001, GRADE strength: very low] but no increased risk of mortality [RR 1.03, 95% CI (0.72-1.40), z =0.06, p =.95. GRADE strength: very low] or major adverse cardiovascular events [RR 1.16, 95% CI (0.67 - 2.01), z =0.54, p =.59, GRADE strength: very low]. A follow-up meta-regression of various comorbidities and demographic variables did not demonstrate a significant contribution to the observed risk ratio for major adverse limb events.

CONCLUSION

Depression was reported in 13% of peripheral arterial disease patients, associated with more medical comorbidity, and a 20% increased risk of major adverse limb events. Although the strength of this evidence is very low, the current state of the literature is still limited. Future studies should prospectively assess the impact of depression and its relationship with medical comorbidities and high risk health behaviors.

Etiology and outcomes of amputation in patients with peripheral artery disease in the EUCLID trial

OBJECTIVE

Amputation remains a frequent and feared outcome in patients with peripheral artery disease (PAD). Although typically characterized as major or minor on the extent of tissue loss, the etiologies and outcomes after amputation by extent are not well-understood. In addition, emerging data suggest that the drivers and outcomes of amputation in patients with PAD may differ in those with and without diabetes mellitus (DM).

METHODS

The EUCLID trial randomized 13,885 patients with symptomatic PAD, including 5345 with concomitant diabetes, to ticagrelor or clopidogrel and followed them for long-term outcomes. Amputations were prospectively reported by trial investigators. Their primary and contributing drivers were adjudicated using safety data, including infection, ischemia, or multifactorial etiologies. Outcomes following major and minor amputations were analyzed, including recurrent amputation, major adverse limb events, adverse cardiovascular events, and mortality. Multivariable logistic regression models were used to identify independent predictors of minor amputations. Analyses were performed overall and stratified by the presence or absence of DM at baseline.

RESULTS

Of the patients randomized, 398 (2.9%) underwent at least one lower extremity nontraumatic amputation, for a total of 511 amputations (255 major and 256 minor) over a median of 30 months. A history of minor amputation was the strongest independent predictor for a subsequent minor amputation (odds ratio, 7.29; 95% confidence interval, 5.17-10.30; P < .001) followed by comorbid DM (odds ratio, 4.60; 95% confidence interval, 3.16-6.69; P < .001). Compared with patients who had a major amputation, those with a minor amputation had similar rates of subsequent major amputation (12.2% vs 13.6%), major adverse limb events (15.1% vs 14.9%), and major adverse cardiovascular events (17.6% vs 16.3%). Ischemia alone was the primary driver of amputation (51%), followed by infection alone (27%), and multifactorial etiologies (22%); however, infection was the most frequent driver in those with DM (58%) but not in those without DM (15%).

CONCLUSIONS

Outcomes after amputation remain poor regardless of whether they are categorized as major or minor. The pattern of amputation drivers in PAD differs by history of DM, with infection being the dominant etiology in those with DM and ischemia in those without DM. Greater focus is needed on the prognostic importance of minor amputation and of the multifactorial etiologies of amputation in PAD. Nomenclature with anatomical description of amputations and eliminating terms "major" or "minor" would seem appropriate.

Update on the pathophysiology and medical treatment of peripheral artery disease

Approximately 6% of adults worldwide have atherosclerosis and thrombosis of the lower limb arteries (peripheral artery disease (PAD)) and the prevalence is rising. PAD causes leg pain, impaired health-related quality of life, immobility, tissue loss and a high risk of major adverse events, including myocardial infarction, stroke, revascularization, amputation and death. In this Review, I describe the pathophysiology, presentation, outcome, preclinical research and medical management of PAD. Established treatments for PAD include antithrombotic drugs, such as aspirin and clopidogrel, and medications to treat dyslipidaemia, hypertension and diabetes mellitus. Randomized controlled trials have demonstrated that these treatments reduce the risk of major adverse events. The drug cilostazol, exercise therapy and revascularization are the current treatment options for the limb symptoms of PAD, but each has limitations. Novel therapies to promote collateral and new capillary growth and treat PAD-related myopathy are under investigation. Methods to improve the implementation of evidence-based medical management, novel drug therapies and rehabilitation programmes for PAD-related pain, functional impairment and ischaemic foot disease are important areas for future research.

Peripheral artery disease leading to major amputation: Trends in revascularization and mortality over 18 years

BACKGROUND

Patients with peripheral artery disease (PAD) are at risk for amputation. The aim of this study was to assess the type of revascularization prior to and the 30-day mortality rate after major amputation due to PAD.

METHODS

Retrospective analysis of consecutive patients undergoing major amputation for PAD between 01/2000 and 12/2017 at a tertiary referral center. The number and target level of ipsilateral revascularizations prior to amputation were analyzed per patient and over the years. There were 3 types of revascularization (open, endovascular and combined treatment) at 3 levels: aortoiliac, femoropopliteal and infrapopliteal. Univariate and multivariate logistic regression models were used to assess the association of level of amputation and patient characteristics with 30-day mortality.

RESULTS

A total of 312 patients (65.7% male) with a mean age of 73.3 ± 11 years underwent 338 major amputations: 70 (21%) above/through knee and 268 (79%) below knee. A median of 2 (interquartile range, IQR 1-4) revascularizations were performed prior to amputation, with a slight decrease of 1.4% per year from 2000-2017 (incidence rate ratio of 0.986 0.974-0.998; Poisson regression analysis, P = 0.021). 16% (53/338) of patients underwent primary amputation without revascularization; this number remained relatively stable throughout the study period. The proportion of exclusively open treatment before amputation decreased substantially from 35% in 2006 to none in 2016, while exclusively endovascular revascularizations were performed increasingly from 17% in 2002 to 64% in 2016. Amputation occurred after a median of 9.5 months (IQR 0.9-67.6 months) if the first revascularization was aortoiliac or femoropopliteal and after 2.1 months (IQR 0.5-13.8 months) if the first intervention was infrapopliteal (P < 0.001) with no significant change over the years (normal linear regression, P= 0.887). Thirty-day mortality was 8.9% (22/247) after below knee and 27.7% (18/65) after above/through knee amputation (adjusted OR 3.84, 95% CI 1.74-8.54, P= 0.001) with a slight increase of mortality over the study period (adjusted OR 1.09, 95% CI 1.018-1.159, Poisson regression analysis, P= 0.021). The uni- and multivariate analysis of patient characteristics did not show an association with mortality, except higher ASA classification (adjusted OR 2.65, 95% CI 1.23-5.72, P= 0.012).

CONCLUSIONS

Mortality, especially after above/through knee amputation, remains high over the past 2 decades. There is a clear shift towards endovascular treatment of patients with PAD prior to major amputation. In patients needing infrapopliteal revascularizations, amputation was performed much sooner than in those with aortoiliac or femoropopliteal interventions, with no improvement over the years. Strategies to extend limb salvage in these patients should be the focus of further research.

Advances in Revascularization for Peripheral Artery Disease: Revascularization in PAD

Effective revascularization of the patient with peripheral artery disease is about more than the procedure. The approach to the patient with symptom-limiting intermittent claudication or limb-threatening ischemia begins with understanding the population at risk and variation in clinical presentation. The urgency of revascularization varies significantly by presentation; from patients with intermittent claudication who should undergo structured exercise rehabilitation before revascularization (if needed) to those with acute limb ischemia, a medical emergency, who require revascularization within hours. Recent years have seen the rapid development of new tools including wires, catheters, drug-eluting technology, specialized balloons, and biomimetic stents. Open surgical bypass remains an important option for those with advanced disease. The strategy and techniques employed vary by clinical presentation, lesion location, and lesion severity. There is limited level 1 evidence to guide practice, but factors that determine technical success and anatomic durability are largely understood and incorporated into decision-making. Following revascularization, medical therapy to reduce adverse limb outcomes and a surveillance plan should be put in place. There are many hurdles to overcome to improve the efficacy of lower extremity revascularization, such as restenosis, calcification, microvascular disease, silent embolization, and tools for perfusion assessment. This review highlights the current state of revascularization in peripheral artery disease with an eye toward technologies at the cusp, which may significantly impact current practice.

Evidence-Based Recommendations for Medical Management of Peripheral Artery Disease

Patients with lower limb artery stenosis or occlusion (peripheral artery disease; PAD) have been determined to be at very high risk of both major adverse cardiovascular events, such as myocardial infarction and stroke, and major adverse limb events, such as amputation and requirement for artery surgery.Effective medical management has been identified as key in reducing this risk; however, this is often poorly implemented in clinical practice. Thus, the aim of this narrative review was to summarize the current evidence on the medical management of PAD in order to inform clinicians and highlight recommendations for clinical practice. International guidelines, randomized controlled trials, and relevant systematic reviews and meta-analyses have been included in this study. The focus was the management of the key modifiable risk factors to mitigate possible adverse events through prescription of anti-platelet and anticoagulation drugs and medications to control low-density lipoprotein cholesterol, blood pressure, and diabetes and aid smoking cessation. The available evidence from randomized clinical trials provide a strong rationale for the need for holistic medical management programs that are effective in achieving uptake of these medical therapies in patients with PAD. In conclusion, people with PAD have some of the highest adverse event rates among those with cardiovascular diseases. Secondary preventive measures have been proven effective in reducing these adverse events; however, they remain to be adequately implemented. Thus, the need for an effective implementation program has emerged to reduce adverse events in this patient group.

The effect of deep vein thrombosis on major adverse limb events in diabetic patients: a nationwide retrospective cohort study

Little is known about the association between deep vein thrombosis (DVT) and arterial complications in patients with type 2 diabetes (T2DM). The aim of this retrospective cohort study was to assess the influence of prior DVT on major adverse limb events (MALEs) and major adverse cardiovascular events (MACEs) in T2DM. A total of 1,628,675 patients with T2DM with or without a history of DVT from 2001 to 2013 were identified in the National Health Insurance Research Database of Taiwan. Before matching, the patients in the DVT group (n = 2020) were older than the control group (66.3 vs. 58.3 years). Patients in the DVT group were more likely to be female than the control group (54.3% vs. 47.5%). Before matching, the DVT group had higher prevalence of most comorbidities, more prescription of antiplatelet, antihypertensive agents and insulins, but less prescription of metformin and sulfonylurea. During a mean follow-up of 5.2 years (standard deviation: 3.9 years), the matched DVT group (n = 2017) have a significantly increased risk of MALE (8.4% vs. 5.2%; subdistribution hazard ratio [SHR] 1.60, 95% CI 1.34-1.90), foot ulcer (5.2% vs. 2.6%, SHR 1.96, 95% CI 1.57-2.45), gangrene (3.4% vs. 2.3%, SHR 1.44, 95% CI 1.10-1.90) and amputation (2.5% vs. 1.7%; SHR 1.42, 95% CI 1.03-1.95) than the 10,085 matched controls without DVT. They also tended to have a greater risk of all-cause mortality (38.1% vs. 33.1%; hazard ratio [HR] 1.18, 95% CI 1.09-1.27) and systemic thromboembolism (4.2% vs. 2.6%; SHR 1.56, 95% CI 1.22-1.99), respectively. We showed the presence of DVT may be associated with an increased risk of MALEs, major amputation, and thromboembolism, contributing to a higher mortality rate in T2DM.