A prospective analysis of critical limb ischemia: factors leading to major primary amputation versus revascularization

Current Status and Principles for the Treatment and Prevention of Diabetic Foot Ulcers in the Cardiovascular Patient Population: A Scientific Statement From the American Heart Association

Despite the known higher risk of cardiovascular disease in individuals with type 2 diabetes, the pathophysiology and optimal management of diabetic foot ulcers (DFUs), a leading complication associated with diabetes, is complex and continues to evolve. Complications of type 2 diabetes, such as DFUs, are a major cause of morbidity and mortality and the leading cause of major lower extremity amputation in the United States. There has recently been a strong focus on the prevention and early treatment of DFUs, leading to the development of multidisciplinary diabetic wound and amputation prevention clinics across the country. Mounting evidence has shown that, despite these efforts, amputations associated with DFUs continue to increase. Furthermore, due to increasing patient complexity of management secondary to comorbid conditions, such as cardiovascular disease, the management of peripheral artery disease associated with DFUs has become increasingly difficult, and care delivery is often episodic and fragmented. Although structured, process-specific approaches exist at individual institutions for the management of DFUs in the cardiovascular patient population, there is insufficient awareness of these principles in the general medicine communities. Furthermore, there is growing interest in better understanding the mechanistic underpinnings of DFUs to better define personalized medicine to improve outcomes. The goals of this scientific statement are to provide salient background information on the complex pathogenesis and current management of DFUs in cardiovascular patients, to guide therapeutic and preventive strategies and future research directions, and to inform public policy makers on health disparities and other barriers to improving and advancing care in this expanding patient population.

A systematic review and meta-analysis on the influence of sociodemographic factors on amputation in patients with peripheral arterial disease

OBJECTIVE

To identify disparities in sociodemographic factors that are associated with major lower limb amputation in patients with peripheral arterial disease (PAD).

METHODS

A systematic review of the literature was performed to identify studies that reported major lower limb amputation rates in patients with PAD among different sociodemographic groups. Data that compared amputation rates on the basis of sex, race, ethnicity, income, insurance, geography, and hospital type were collected and described. Outcomes were then aggregated and standardized, and a meta-analysis was performed to synthesis data into single odds ratios (ORs).

RESULTS

Forty-one studies were included in the review. There was no association found between males and females (OR, 0.95; 95% confidence interval [CI], 0.90-1.00). Compared with Whites, higher rates of amputation were seen among Blacks/African Americans (OR, 2.02; 95% CI, 1.81-2.26) and Native Americans (OR, 1.22; 95% CI, 1.04-1.45). No significant association was found between Whites and Asians, Native Hawaiians, or Pacific Islanders (OR, 1.15; 95% CI, 1.00-1.33). Hispanics had higher rates of amputation compared with non-Hispanics (OR, 1.36; 95% CI, 1.22-1.52). Compared with private insurance, higher rates of amputation were seen among Medicare patients (OR, 1.38; 95% CI, 1.27-1.50), Medicaid patients (OR, 1.59; 95% CI, 1.44-1.76), and noninsured patients (OR, 1.41; 95% CI, 1.02-1.95). Compared with the richest income quartile, higher rates of amputation were seen among the second income quartile (OR, 1.10; 95% CI, 1.05-1.15), third income quartile (OR, 1.20; 95% CI, 1.07-1.35), and bottom income quartile (OR, 1.36; 95% CI, 1.24-1.49). There was no association found between rural and urban populations (OR, 1.35; 95% CI, 0.92-1.97) or between teaching and nonteaching hospitals (OR, 1.01; 95% CI, 0.91-1.12).

CONCLUSIONS

Our study has identified a number of disparities and quantified the influence of sociodemographic factors on major lower limb amputation rates owing to PAD between groups. We believe these findings can be used to better target interventions aimed at decreasing amputation rates, although further research is needed to better understand the mechanisms behind our findings.

Understanding the multifaceted etiopathogenesis of foot complications in individuals with diabetes

Diabetes mellitus, a chronic disease of metabolism, is characterized by a disordered production or cellular utilization of insulin. Diabetic foot disease, which comprises the spectrum of infection, ulceration, and gangrene, is one of the most severe complications of diabetes and is the most common cause of hospitalization in diabetic patients. The aim of this study is to provide an evidence-based overview of diabetic foot complications. Due to neuropathy, diabetic foot infections can occur in the form of ulcers and minor skin lesions. In patients with diabetic foot ulcers, ischemia and infection are the main causes of non-healing ulcers and amputations. Hyperglycemia compromises the immune system of individuals with diabetes, leading to persistent inflammation and delayed wound healing. In addition, the treatment of diabetic foot infections is challenging due to difficulty in accurate identification of pathogenic microorganisms and the widespread issue of antimicrobial resistance. As a further complicating factor, the warning signs and symptoms of diabetic foot problems can easily be overlooked. Issues associated with diabetic foot complications include peripheral arterial disease and osteomyelitis; accordingly, the risk of these complications in people with diabetes should be assessed annually. Although antimicrobial agents represent the mainstay of treatment for diabetic foot infections, if peripheral arterial disease is present, revascularization should be considered to prevent limb amputation. A multidisciplinary approach to the prevention, diagnosis, and treatment of diabetic patients, including those with foot ulcers, is of the utmost importance to reduce the cost of treatment and avoid major adverse consequences such as amputation.

Below Knee Angioplasty Using Drug-Eluting Balloons in Patients with Critical Limb Ischemia with Six Months Follow-Up: Single-Center Experience at Tertiary Care Hospital

Aims and Objective The aim of this study was to evaluate 6 monthly safety and primary patency rates of drug-eluting balloons (DEB) angioplasty in below-the-knee (BTK) arteries in critical limb ischemia (CLI) patients.

Methods A prospective observational study was conducted over 2 years in a tertiary care center. A total of 25 patients with CLI were enrolled in this study. Inclusion criteria were patients presenting with CLI (Rutherford class 4 or greater), equal to or more than 50% luminal stenosis or occlusion of at least one tibial artery, and agreement to 6-month evaluation. Exclusion criteria were life expectancy less than 1 year, allergy to paclitaxel, and contraindication to antiplatelet treatment.

Follow-up was performed by clinical and Doppler assessment. The primary endpoint was a 6-month primary patency rate, and secondary endpoints were changes in the Rutherford class and incidence of major amputation. Restenosis rate is defined as a reduction in the luminal diameter by 50% or greater by duplex ultrasound.

Results Six-month primary patency was achieved in 19 (76%) patients. Both Rutherford category improvement and reduction in the percentage of stenosis after angioplasty were statistically significant (p-value <0.0001). At 6 months, better patency rates were seen among diabetics (88.8%) than smokers (69.2%). Limb salvage was observed in 24 (96%) patients with one major amputation (above the ankle).

Conclusion DEBs have shown safe and promising clinical outcomes with successful performance in infrapopliteal arteries in the short-term follow-up. DEB had a substantial 6-month primary patency rate. DEB angioplasty is a safe and effective treatment option for CLI patients with BTK vascular disease.

Major Lower Limb Amputations and Amputees in an Aging Population in Southwest Finland 2007-2017

Purpose

The aim of the present study was to describe and analyze changes in the incidences of lower extremity amputations (LEAs), patient characteristics, vascular history of amputees and survival in Southwest Finland.

Patients and Methods

This is a retrospective patient study in the Hospital District of Southwest Finland. All consecutive patients with atherosclerosis and diabetes-caused LEA, between 1st January 2007 and 31st December 2017, were included. The annual incidences of major LEA patients were statistically standardized. Patients' diagnoses, functional status, previous revascularizations and minor amputations were recorded, and survival was analyzed.

Results

During the 11-year-period major LEAs were performed on 891 patients, 118 (13.2%) were urgent operations. The overall incidence of major LEA was 17.2/100 000 and was age-dependent (3.1 for ≤64 years, 34.3 for 65-74 years, 81.5 for 75-84 years, 216 for ≥85 years). A decrease in incidence was detected in the <65 year-age-group (incidence 4.98 in 2007 and 1.88 in 2017; p = 0.0018). Among older age groups, there was no significant change. Half (50.6%) of all amputees were diabetics. Altogether, 472 patients (53.0%) had a history of revascularization before LEA. 80.1% of index amputations were transfemoral and 19.9% transtibial. Re-surgery was performed on 94 (10.5%) patients. The 1-, 3- and 5-year overall survival were 56%, 30%, and 18%, respectively.

Conclusion

Our results suggest that in an aging population, despite good availability of vascular services, a significant number of patients are not fit for active revascularization, and LEA is the only feasible treatment for critical limb ischemia.

Assessing Resident Impact on Surgical Outcomes in Below-the-Knee Amputations Based on Operative Autonomy

BACKGROUND

Gradual increases in resident autonomy with attending physician oversight is crucial to developing safe and competent surgeons¹. The Veterans Affairs Surgical Quality Improvement Program (VASQIP) follows surgical outcomes within the VA. We set forth to examine the VASQIP database to compare outcomes between resident independent cases and nonindependent cases during below-the-knee amputations (BKA).

METHODS

All VASQIP records for BKA from 2000 to 2020 were examined and categorized based on whether the attending was scrubbed during the case. Case matching was performed based on preoperative comorbidities; 30-day postoperative outcomes, including a return to the operating room, wound infection, and mortality, were assessed in addition to operative time, hospital length of stay, and transfusion requirements. Student's t-test and Fisher's Exact Test were utilized.

RESULTS

A total of 13,208 BKA VASQIP records were obtained. After case control matching, 2,688 cases remained. Cases were identified with the attending surgeon noted as being scrubbed during the case (n = 1,344), or not scrubbed (n = 1,344). Patients were similar in comorbidities across both groups. No statistically significant difference in operative time (1.52 hr ± 0.78 vs. 1.47 hr ± 0.75, P = 0.08), 30-day mortality (3.3% vs. 4.8%, P = 0.05), or complication rate (19.5% vs. 21.3%, P = 0.25). Resident independent cases were noted to have slightly longer postop length of stay (12.47 days ± 12.69 vs. 15.33 days ± 20.56, P < 0.01) and operative bleeding requiring more than 4 units transfused (0.3% vs. 1.3%, P ≤ 0.01).

CONCLUSIONS

Resident independent operating during below-the-knee amputation at VA hospitals is associated with an increased length of stay and blood transfusion. There was no statistically significant increase in operative time, 30-day mortality, or total complication rate. Further research is required to assess the risks associated with surgical training, resident supervision, and resident preparedness for independent practice.

Amputation as a First Treatment is Highly Associated With Late Presentation: An Underestimated Modifiable Major Risk Factor for Diabetic Foot Ulcer

PURPOSE

Several risk factors for lower extremity amputation in diabetic patients have been identified; however, late presentation has been poorly investigated. Very few studies looked at the impact of such risk factor. As none has investigated the link between admission to amputation and late presentation in this population, we investigated such association.

METHODS

The study is a retrospective comparative cohort of continuous series of patients admitted for amputation related to diabetic foot ulcer (DFU) as a first treatment. A late presentation was defined as a period of 3 weeks or more from the onset of the ulcer.

RESULTS

Forty-six patients admitted for amputation and all wounds were infected and located on the plantar forefoot in 32 cases (69.5%), on the toes in 10 cases (21.7%), and in the heel area in 4 cases (8.8%). The mean duration to admission was 5.2 ±1.8 weeks (range 4-10 weeks). Late presentation was recorded in 42 (91.3%) patients.

CONCLUSION

This study demonstrates that amputation due to DFU is highly associated with late presentation. Educational campaigns targeting patient and first-line health care providers and highlighting the urgency of diabetic ulcers are needed to impact this major modifiable risk factor.Levels of Evidence: Therapeutic, Level III: Retrospective Comparative.

Racial disparities in surgical management and outcomes of acute limb ischemia in the United States

Background

Although significant racial disparities in the surgical management of lower extremity critical limb threatening ischemia have been previously reported, data on disparities in lower extremity acute limb ischemia are lacking.

Methods

The 2012–2018 National Inpatient Sample was queried for all adult hospitalizations for acute limb ischemia (N = 225,180). Hospital-specific observed-to-expected rates of major lower extremity amputation were tabulated. Multivariable logistic and linear models were developed to assess the impact of race on amputation and revascularization.

Results

Nonwhite race was associated with significantly increased odds of overall (adjusted odds ratio: 1.16, 95% confidence interval 1.06–1.28) and primary (adjusted odds ratio: 1.34, 95% confidence interval 1.17–1.53) major amputation, decreased odds of revascularization (adjusted odds ratio 0.79, 95% confidence interval 0.73–0.85), but decreased in-hospital mortality (adjusted odds ratio: 0.86, 95% confidence interval 0.74–0.99). The nonwhite group incurred increased adjusted index hospitalization costs (β: +$4,810, 95% confidence interval 3,280-6,350), length of stay (β: + 1.09 days, 95% confidence interval 0.70–1.48), and nonhome discharge (adjusted odds ratio: 1.15, 95% confidence interval 1.06–1.26).

Conclusion

Significant racial disparities exist in the management of and outcomes of lower extremity acute limb ischemia despite correction for variations in hospital amputation practices and other relevant hospital and patient characteristics. Whether the etiology lies primarily in patient, institution, or healthcare provider–specific factors has not yet been determined. Further studies of race-based disparities in management and outcomes of acute limb ischemia are warranted to provide effective and equitable care to all.

Healthcare disparities in vascular surgery: A critical review

Health disparities in vascular surgical care have existed for decades. Persons categorized as Black undergo a nearly twofold greater risk-adjusted rate of leg amputations. Persons categorized as Black, Latinx, and women have hemodialysis initiated via autogenous fistula less often than male persons categorized as White. Persons categorized as Black, Latino, Latina, or Latinx, and women are less likely to undergo carotid endarterectomy for symptomatic carotid stenosis and repair of abdominal aortic aneurysms. New approaches are needed to address these disparities. We suggest surgeons use data to identify groups that would most benefit from medical care and then partner with community organizations or individuals to create lasting health benefits. Surgeons alone cannot rectify the structural inequalities present in American society. However, all surgeons should contribute to ensuring that all people have access to high-quality vascular surgical care.

Reducing Nontraumatic Lower-Extremity Amputations by 20% by 2030: Time to Get to Our Feet: A Policy Statement From the American Heart Association

Nontraumatic lower-extremity amputation is a devastating complication of peripheral artery disease (PAD) with a high mortality and medical expenditure. There are ≈150 000 nontraumatic leg amputations every year in the United States, and most cases occur in patients with diabetes. Among patients with diabetes, after an ≈40% decline between 2000 and 2009, the amputation rate increased by 50% from 2009 to 2015. A number of evidence-based diagnostic and therapeutic approaches for PAD can reduce amputation risk. However, their implementation and adherence are suboptimal. Some racial/ethnic groups have an elevated risk of PAD but less access to high-quality vascular care, leading to increased rates of amputation. To stop, and indeed reverse, the increasing trends of amputation, actionable policies that will reduce the incidence of critical limb ischemia and enhance delivery of optimal care are needed. This statement describes the impact of amputation on patients and society, summarizes medical approaches to identify PAD and prevent its progression, and proposes policy solutions to prevent limb amputation. Among the actions recommended are improving public awareness of PAD and greater use of effective PAD management strategies (eg, smoking cessation, use of statins, and foot monitoring/care in patients with diabetes). To facilitate the implementation of these recommendations, we propose several regulatory/legislative and organizational/institutional policies such as adoption of quality measures for PAD care; affordable prevention, diagnosis, and management; regulation of tobacco products; clinical decision support for PAD care; professional education; and dedicated funding opportunities to support PAD research. If these recommendations and proposed policies are implemented, we should be able to achieve the goal of reducing the rate of nontraumatic lower-extremity amputations by 20% by 2030.

Disparities in amputation in patients with peripheral arterial disease

BACKGROUND

To describe peripheral arterial disease-related amputation as a marker for health disparities.

Seasonal variation in U.S. hospitalizations for chronic limb-threatening ischemia

BACKGROUND

Seasonal variation in coronary artery disease is well described, with a peak in the winter and a trough in the summer. However, little is known about seasonal trends in hospital admission for critical limb-threatening ischemia (CLTI) and associated outcomes.

METHODS

Patients admitted with CLTI from January 1, 2012 through August 31, 2015 were identified in the Healthcare Cost and Utilization Project's National Inpatient Sample based upon administrative claims diagnosis codes. The primary outcome was seasonal hospitalization incidence, and secondary outcomes included mortality rates and rates of in-hospital major and minor amputations among nondiabetics and diabetics.

RESULTS

Of 1,276,745 hospitalizations for CLTI during the study period, 28.3% occurred in the spring, the peak admission season, and 19.1% occurred in the fall, the nadir. In-hospital mortality was highest during the winter (adjusted odds ratio [OR]: 1.08; 95% confidence interval [CI]: 1.03-1.14), and followed the highest seasonal rates of influenza in the fall; however, other important comorbidities did not differ significantly by season. For the overall cohort, there was no significant seasonal variation in rates of major or minor amputation, although seasonal rates were different according to diabetic status. Patients without diabetes had the highest odds of amputation in the spring (OR 1.07; 95% CI: 1.02-1.12), although this trend was not identified among patients with diabetes.

CONCLUSIONS

There is significant seasonal variability in CLTI admissions and mortality but minimal variability in amputation rates. Understanding the seasonal variation in CLTI may help to identify individuals at greatest risk for hospitalization and death through patient and provider education efforts.

A meta-analysis of mortality after minor amputation among patients with diabetes and/or peripheral vascular disease

OBJECTIVE

Foot complications in patients with diabetes or peripheral artery disease (PAD) are serious events in the life of these patients that often lead to amputations and mortality. No evidence synthesis has been reported on the mortality rates after minor lower extremity amputation; thus, a quantitative evidence synthesis was needed.

METHODS

A systematic literature search was performed to identify studies that had reported the survival or mortality rates after a minor LEA. The studies were required to include one or more of the following primary outcomes: mortality rate at 30 days, 1 year, 3 years, 5 years, 6 to 7 years, or 8 to 9 years. The secondary outcomes were the mortality rates according to the anatomic location of the amputation in the foot and the independent risk factors for mortality.

RESULTS

A total of 28 studies with 17,325 subjects fulfilled the inclusion criteria. The meta-analytical results of the mortality rates were as follows: 3.5% at 1 month, 20% at 1 year, 28% at 3 years, 44.1% at 5 years, 51.3% at 6 to 7 years, and 58.5% at 8 to 9 years. From these studies of diabetic patients, age was the most consistent independent risk factor, followed by chronic kidney disease, PAD, and coronary artery disease. One study of patients with PAD had reported diabetes as an independent risk factor for mortality. The subgroup analysis of the four studies reporting the outcomes of patients with PAD showed greater 3- and 5-year mortality rates compared with the overall and "diabetic" results.

CONCLUSIONS

Mortality after minor amputation for patients with diabetes and/or PAD was found to be very high. Compared with the reported cancer data, survival was worse than that for many cancers. Just as in the case of major amputations, minor amputations should be considered a pivotal event in the life of these patients.

One-Year Outcomes of Peripheral Endovascular Device Intervention in Critical Limb Ischemia Patients: Sub-Analysis of the LIBERTY 360 Study

Background

High-risk patients with advanced peripheral artery disease (PAD), including critical limb ischemia (CLI), are often excluded from peripheral endovascular device intervention clinical trials, leading to difficulty in translating trial results into real-world practice. There is a need for prospectively assessed studies to evaluate peripheral endovascular device intervention outcomes in CLI patients.

Methods

LIBERTY 360 is a prospective, observational, multi-center study designed to evaluate the procedural and long-term clinical outcomes of peripheral endovascular device intervention in real-world patients with symptomatic lower-extremity PAD. One thousand two hundred and four patients were enrolled and stratified based on Rutherford Classification (RC): RC2-3 (N=501), RC4-5 (N=603), and RC6 (N=100). For this sub-analysis, RC5 and RC6 patients (RC5-6; N=404) were pooled and 1-year outcomes were assessed.

Results

Procedural complications rarely (1.7%) resulted in post-procedural hospitalization and 89.1% of RC5-6 patients were discharged to home. Considering the advanced disease state in RC5-6 patients, there was a high freedom from 1-year major adverse event rate of 65.5% (defined as target vessel revascularization, death to 30 days, and major target limb amputation). At 1 year, freedom from major amputation was 89.6%. Wounds identified at baseline on the target limb had completely healed in 172/243 (70.8%) of the RC5-6 subjects by 1 year. Additionally, the overall quality of life, as measured by VascuQoL, improved from baseline to 1 year.

Conclusion

LIBERTY investigated real-world PAD patients with independent oversight of outcomes. This analysis of LIBERTY RC5-6 patients demonstrates that peripheral endovascular device intervention can be successful in CLI patients, with low rates of major amputation and improvement in wound healing and quality of life through 1-year follow-up.

LIBERTY 360, https://clinicaltrials.gov/ct2/show/NCT01855412, ClinicalTrials.gov Identifier: NCT01855412.

Use of home negative pressure wound therapy in peripheral artery disease and diabetic limb salvage

Use of negative pressure wound therapy (NPWT) in peripheral artery disease (PAD) and diabetic limb salvage (DLS) improves wound healing by providing moist wound conditions, reducing exudate, controlling wound-bed infection, and stimulating granulation. NPWT duration may take several weeks, and home-based NPWT allows patient to recover in the community while minimising risks of prolonged hospitalisation. The aim of this study is to review the use and outcomes of home NPWT in PAD and DLS. The methodology is the retrospective review of patients who were discharged with home NPWT after in-patient PAD revascularisation and DLS debridement or minor amputations. The results included a total of 118 patients who received home NPWT between January 2017 and December 2017. The mean age was 62.8 years with 66% male and 34% female patients. The study population comprised 25% smokers, 98% patients with diabetics, 35% with ischemic heart disease, and 21% with end-stage renal failure (ESRF). Of which, 56% of patients required revascularisation while 31% of patients underwent foot debridement, 48% underwent toe amputations, and 20% underwent forefoot amputations. All patients received in-patient NPWT for a week before being discharged on home NPWT for 4 weeks. Then, 62% received targeted antibiotics regime while 36% received empirical antibiotics on discharge; 60% of patients achieved wound healing on home NPWT, with 9% requiring split-thickness skin graft; 4% required further surgical debridement, 16% required further minor amputation while 20% required major amputation. 9% required further home NPWT extension, with a mean length of 7.1 ± 4.7 weeks' extension. Overall survival of 1 year was 89%. Risk factors that predict the failure of home NPWT includes subjects with a background of ESRF and wet gangrene on presentation. Home NPWT is a useful adjunct in the management of PAD and DLS foot wounds.

The effect of rurality on the risk of primary amputation is amplified by race

OBJECTIVE

Primary amputation (ie, without attempted revascularization) is a devastating complication of peripheral artery disease. Racial disparities in primary amputation have been described; however, rural disparities have not been well investigated. The purpose of this study was to examine the impact of rurality on risk of primary amputation and to explore the effect of race on this relationship.

METHODS

The national Vascular Quality Initiative amputation data set was used for analyses (N = 6795). The outcome of interest was primary amputation. Independent variables were race/ethnicity (non-Latinx whites vs nonwhites) and rural residence. Multivariable logistic regression examined impact of rurality and race/ethnicity on primary amputation after adjustment for relevant covariates and included an interaction for race/ethnicity by rural status.

RESULTS

Primary amputation occurred in 49% of patients overall (n = 3332), in 47% of rural vs 49% of urban patients (P = .322), and in 46% of whites vs 53% of nonwhites (P < .001). On multivariable analysis, nonwhites had a 21% higher odds of undergoing primary amputation overall (adjusted odds ratio [AOR], 1.21; 95% confidence interval [CI], 1.05-1.39). On subgroup analysis, rural nonwhites had two times higher odds of undergoing primary amputation than rural whites (AOR, 2.06; 95% CI, 1.53-2.78) and a 52% higher odds of undergoing primary amputation than urban nonwhites (AOR, 1.52; 95% CI, 1.19-1.94). In the urban setting, nonwhites had a 21% higher odds of undergoing primary amputation than urban whites (AOR, 1.21; 95% CI, 1.05-1.39).

CONCLUSIONS

In these analyses, rurality was associated with greater odds for primary amputation in nonwhite patients but not in white patients. The effect of race on primary amputation was significant in both urban and rural settings; however, the effect was significantly stronger in rural settings. These findings suggest that race/ethnicity has a compounding effect on rural health disparities and that strategies to improve health of rural communities need to consider the particular needs of nonwhite residents to reduce disparities.

Trends in the Types of Physicians Performing Partial Foot Amputations

BACKGROUND

Partial foot amputations (PFAs) are often indicated for the treatment of severe infection, osteomyelitis, and critical limb ischemia, which consequently leads to irreversible necrosis. Many patients who undergo PFAs have concomitant comorbidities and generally present with a severe acute manifestation of the condition, such as gangrenous changes, systemic infection, or debilitating pain, which would then require emergency amputation on an inpatient basis.

METHODS

The purpose of this study was to track the recent prevalence of PFAs and to investigate the current demographic trends of the physicians managing and performing PFAs, specifically regarding medical degree and specialty. Doctors of podiatric medicine are striving to achieve parity with their allopathic and osteopathic surgical counterparts and become a more prominent part of the multidisciplinary approach to limb salvage and emergency surgical treatment. This study evaluated 4 years (2009-2012) of PFA data from the Pennsylvania state inpatient database in the two most populated areas of Pennsylvania: Philadelphia and Allegheny counties. Statistics on medical schools were obtained directly from the accrediting bodies of allopathic, osteopathic, and podiatric medical schools. The goal of this study was to evaluate the general trends of patients undergoing a PFA and to quantify the upswing of podiatric surgeons intervening in the surgical care of these patients.

RESULTS

The number of partial foot amputations in the United States rose from 2006 to 2012. Podiatric surgeons performed 46% of theses procedures for residents of Philadelphia County from 2009 to 2012. In Allegheny County podiatric physicians performed 42% of these procedures during the same time frame.

CONCLUSIONS

Partial foot amputations are increasing over time. Podiatric Surgeons perform a significant share of these operations. This share is increasing in the most populated areas of Pennsylvania.

Risk of contralateral lower limb amputation and death after initial lower limb amputation - a population-based study

Background

Lower limb amputation (LLA) is a complication of lower limb atherosclerosis, infection and tissue gangrene. Following ipsilateral LLA, the risk of major amputation of the contralateral limb or of death is unknown. The aim of this study was to determine the incidence of a contralateral major LLA, comparing those with a non-malignant/non-traumatic ipsilateral major vs. ipsilateral minor LLA.

Methods

We used pre-existing linked administrative health databases for the study. Data were provided by the Institute for Clinical Evaluation Sciences (ICES), Toronto, Ontario. This is a retrospective population-based cohort study across Ontario, Canada, 2002–2012. Cause-specific Cox regression models were used to obtain hazard ratios. Cumulative incidence functions were used to calculate the risk of contralateral major LLA and the risk of the competing event death. Individuals who did not survive at least 30 days after their first ipsilateral LLA were excluded since they were ineligible to have a contralateral LLA.

Results

5,816 adults underwent an ipsilateral major and 4,143 an ipsilateral minor LLA. The incidences of contralateral major LLA were 4.8 and 2.2 (adjusted HR 2.41, 95% CI 2.04–2.84) after ipsilateral major and minor LLA, respectively. Incidence of death was 18.9 and 11.4 (adjusted HR 1.22, 95% CI 1.13–1.31) following ipsilateral major and minor LLA, respectively.

Conclusion

There is high incidence of a contralateral major LLA and even higher risk of death following the ipsilateral LLA. Healthcare professionals should develop strategies for contralateral limb preservation in individuals with existing ipsilateral LLA.

Mortality after major amputation in elderly patients with critical limb ischemia

Background

Owing to the aging population, the number of elderly patients with critical limb ischemia (CLI) has increased. The consequence of amputation is immense. However, at the moment, information about the mortality after amputation in the elderly vascular patients is unknown. For this reason, this study evaluated mortality rates and patient-related factors associated with mortality after a major amputation in elderly patients with CLI.

Methods

From 2006 to 2013, we included patients aged >70 years who were treated for chronic CLI by primary or secondary major amputation within or after 3 months of initial therapy (revascularization or conservative management). Outcome measurements were mortality after major amputation and factors associated with mortality (age, comorbidity and timing of amputation).

Results

In total, 168/651 patients (178 legs; 26%) underwent a major amputation. Patients were stratified by age: 70–80 years (n=86) and >80 years (n=82). Overall mortality after major amputation was 44%, 66% and 85% after 1, 3 and 5 years, respectively. The 6-month and 1-year mortality in patients aged 80 years or older was, respectively, 59% or 63% after a secondary amputation <3 months versus 34% and 44% after a secondary amputation >3 months. Per year of age, the mortality rate increased by 4% (P=0.005). No significant difference in mortality after major amputation was found in the presence of comorbidity or according to Rutherford classification.

Conclusion

Despite developments in the treatment of CLI by revascularization, amputation rates remain high and are associated with tremendous mortality rates. Secondary amputation after a failed attempt of revascularization causes a higher mortality. Further research concerning timing of amputation and patient-related outcome is needed to evaluate if selected patients might benefit from primary amputation.

Critical Limb Ischemia: A Practical Up-To-Date Review

Critical limb ischemia (CLI) is the most advanced form of peripheral artery disease. It is associated with significant morbidity and mortality and high management costs. It carries a high risk of amputation and local infection. Moreover, cardiovascular complications remain a major concern. Although it is a well-known entity and new technological and therapeutic advances have been made, this condition remains poorly addressed, with significantly heterogeneous management, especially in nonexperienced centers. This review, from a third-level dedicated inpatient and outpatient cardioangiology structure, aims to provide an updated summary on the topic of CLI of its complexity, encompassing epidemiological, social, economical and, in particular, diagnostic/imaging issues, together with potential therapeutic strategies (medical, endovascular, and surgical), including the evaluation of cardiovascular risk factors, the diagnosis, and treatment together with prognostic stratification.

Revascularization Surgery: Its Efficacy for Limb Salvage in Diabetic Foot

The estimated prevalence of diabetes is 9.78% in Taiwan. The lifetime risk for patients with diabetes to have foot ulcers might be as high as 25%. About 15% of these patients require major limb amputation because of ischemia and infection. Peripheral artery disease is still a major problem involved in diabetic foot disease and the cause for major amputation despite an increase in the prevalence of revascularization surgery and new revascularization techniques over the past 20 years. We investigated the major limb amputation rates in patients with diabetic foot and critical limb ischemia who had undergone revascularization surgery in our hospital. The records of 42 patients who had undergone revascularization surgery for diabetic foot were retrospectively reviewed. Nineteen patients (45%) required major limb amputation despite revascularization. The affected limbs of only 15 patients (36%) were salvaged. Four patients died soon after surgery because of comorbidities, and another 4 were lost to follow-up. Two patients died from procedure-related sepsis, and overall perioperative mortality was 4.8%. Ten predictive risk factors (duration of diabetes, history of smoking, coronary artery disease, congestive heart failure, cerebral vascular accident, contralateral amputation, end-stage renal disease, fever episode, wound infection severity score, and arterial obstruction level) were included for analysis. Although none was significant, long-duration diabetes (OR: 1.13), end-stage renal disease (OR: 10.02), wound infection (OR: 1.56), and infrapopliteal lesions (OR: 3.00) tended to be unfavorable predictive risk factors of limb amputation. Revascularization surgery is still potentially beneficial for these patients--eg, it decreases the contralateral limb amputation rate by 7.5%--if done early in high-risk patients.

Mortality After Nontraumatic Major Amputation Among Patients With Diabetes and Peripheral Vascular Disease: A Systematic Review

High mortality rates have been reported after major amputations of a lower limb secondary to diabetes and peripheral vascular disease. However, the mortality rates have varied across studies. A systematic review of the 5-year mortality after nontraumatic major amputations of the lower extremity was conducted. A data search was performed of Medline using OVID, CINHAL, and Cochrane, 365 abstracts were screened, and 79 full text articles were assessed for eligibility. After review, 31 studies met the inclusion and exclusion criteria. Overall, the 5-year mortality rate was very high among patients with any amputation (major and minor combined), ranging from 53% to 100%, and in patients with major amputations, ranging from 52% to 80%. Mortality after below-the-knee amputation ranged from 40% to 82% and after above-the-knee amputation from 40% to 90%. The risk factors for increased mortality included age, renal disease, proximal amputation, and peripheral vascular disease. Although our previous systematic review of the 5-year mortality after ulceration had much lower rates of death, additional studies are warranted to determine whether amputation hastens death or is a marker for underlying disease severity.

Literature review on the management of diabetic foot ulcer

Diabetic foot ulcer (DFU) is the most costly and devastating complication of diabetes mellitus, which affect 15% of diabetic patients during their lifetime. Based on National Institute for Health and Clinical Excellence strategies, early effective management of DFU can reduce the severity of complications such as preventable amputations and possible mortality, and also can improve overall quality of life. The management of DFU should be optimized by using a multidisciplinary team, due to a holistic approach to wound management is required. Based on studies, blood sugar control, wound debridement, advanced dressings and offloading modalities should always be a part of DFU management. Furthermore, surgery to heal chronic ulcer and prevent recurrence should be considered as an essential component of management in some cases. Also, hyperbaric oxygen therapy, electrical stimulation, negative pressure wound therapy, bio-engineered skin and growth factors could be used as adjunct therapies for rapid healing of DFU. So, it’s suggested that with appropriate patient education encourages them to regular foot care in order to prevent DFU and its complications.

The impact of foot ulceration and amputation on mortality in diabetic patients. I: From ulceration to death, a systematic review

A great deal of emphasis, clinical and financial, is placed on limb salvage efforts in diabetic patients suffering from lower extremity ulceration. This is because of the impression that amputation in such patients may be a proximal cause of death. While amputation is certainly a negative clinical outcome, it is not entirely clear that it causes death. In this systematic review, we examine the available literature to attempt to understand the role that the ulceration itself may play in mortality. In brief, we searched for human studies in OVID, CINAHL and the COCHRANE CENTRAL DATABASE from 1980 to 2013, looking for articles related to ulcer or wound of the foot, in patients with diabetes or peripheral vascular disease, and death. We looked for articles with 5 years of follow-up, or Kaplan-Meier estimates of 5-year mortality, and excluded reviews and letters. Articles were assessed for quality and potential bias using the Newcastle-Ottawa scale. We find that while the patient populations studied varied widely in terms of demographics and comorbidities, limiting generalisability, 5-year mortality rates after ulceration were around 40%. Risk factors for death commonly identified were increased age, male gender, peripheral vascular disease and renal disease.

Saving the Limb in Diabetic Patients With Ischemic Foot Lesions Complicated by Acute Infection

Ischemia and infection are the most important factors affecting the prognosis of foot ulcerations in diabetic patients. To improve the outcome of these patients, it is necessary to aggressively treat 2 important pathologies—namely, occlusive arterial disease affecting the tibial and femoral arteries and infection of the ischemic diabetic foot. Each of these 2 conditions may lead to major limb amputation, and the presence of both critical limb ischemia (CLI) and acute deep infection is a major risk factor for lower-extremity amputation. Thus, the management of diabetic foot ulcers requires specific therapeutic approaches that vary significantly depending on whether foot lesions are complicated by infection and/or ischemia. A multidisciplinary team approach is the key to successful treatment of a diabetic foot ulcer: ischemic diabetic foot ulcers complicated by acute deep infection pose serious treatment challenges because high levels of skill, organization, accuracy, and timing of intervention are required to maximize the chances of limb salvage: these complex issues are better managed by a multidisciplinary clinical group.

Limb salvage in women

The prevalence of peripheral arterial occlusive disease (PAD) in women and men is equal. Studies to date present conflicting data of gender effects on the risk factors, clinical presentation, and treatment outcomes. Clinical trials have often failed to analyze results by gender or to recruit sufficient women to enable such an analysis. This review summarizes the management and outcome of limb salvage therapy with a particular focus in women.

Effectiveness of combined therapy with angiotensin-converting enzyme inhibitors and statins in reducing mortality in diabetic patients with critical limb ischemia: an observational study

AIMS

To investigate the effect of combined treatment with angiotensin-converting enzyme inhibitors (ACE) and statins on mortality in diabetic patients with critical limb ischemia (CLI).

METHODS

Prospective observational study of 553 consecutive diabetic patients admitted because of CLI followed for a mean of 2.2 years. All patients underwent peripheral revascularization and antithrombotic therapy was prescribed or continued and therapy with statin and ACE was recorded. Mortality from any cause was assessed and Kaplan-Meier analyses were performed to compare the relationship between survival and recorded variables.

RESULTS

One hundred thirty-nine patients did not have therapy with statin or an ACE, 78 had therapy with statin without ACE, 164 had therapy with ACE without statin and 172 patients had therapy with both statin and ACE. One hundred thirty-six patients died, 45/139 with neither statin nor ACE, 40/164 with ACE only, 26/78 with statin only, and 25/172 with both statin and ACE. Multivariate analysis confirmed the independent role of age, history of stroke, renal insufficiency and dialysis. Combined treatment with ACE and statin appeared to have a protective role.

CONCLUSIONS

In patients with diabetes and CLI mortality after two years is high. Life expectancy was better in patients receiving combined therapy with ACE and statin but not with therapy with only a statin or an ACE.

Pioglitazone inhibits HIF-1α-dependent angiogenesis in rats by paracrine and direct effects on endothelial cells

Abstract

Pioglitazone was associated with increased hazard for surgical or percutaneous lower extremity revascularization in patients with diabetes in a large clinical trial, but this clinical finding has not been adequately explored in animal models. We hypothesized that pioglitazone would decrease hypoxia-inducible factor 1α (HIF-1α)-dependent angiogenesis in rat ischemic hindlimb models by altering mitochondrial-derived signals supporting HIF-1α activation. We tested oral pioglitazone (10 mg/kg/day) versus placebo in two cohorts of rats with hindlimb ischemia (normal Sprague–Dawley rats and insulin-resistant JCR:La-cp rats), and evaluated direct and paracrine effects of pioglitazone on angiogenesis in vitro using human skeletal muscle and endothelial cells. Pioglitazone treatment was associated with reductions in limb perfusion at 2 weeks measured by contrast-enhanced ultrasound and Tc^99m-Sestamibi SPECT-CT. Ischemic muscle capillary density was also reduced by pioglitazone. HIF-1α and vascular endothelial growth factor (VEGF) expression in ischemic muscle were also reduced by pioglitazone. In vitro, pioglitazone's effects on both skeletal muscle cells and microvascular endothelial cells were associated with a decrease in autocrine and paracrine angiogenesis measured by matrigel assay, decreased HIF-1α expression and activation, as well as increases in both mitochondrial reactive oxygen species and α-ketoglutarate, both mitochondria-derived signals which promote HIF-1α degradation. We conclude that pioglitazone is associated with decreased ischemic limb perfusion and capillary density in relevant rat models of hindlimb ischemia, and these effects are mediated by mitochondria-dependent reductions in HIF-1α-dependent angiogenesis.

Key messages

Pioglitazone inhibits angiogenesis in rats with and without insulin resistance.

Pioglitazone inhibits HIF-1α by inhibiting mitochondrial stabilization of HIF-1.

Pioglitazone inhibits both autocrine and paracrine angiogenesis.

Inhibition of angiogenesis may explain unexpected results of a pioglitazone human clinical trial.

Electronic supplementary material

The online version of this article (doi:10.1007/s00109-013-1115-0) contains supplementary material, which is available to authorized users.

Transcutaneous oxygen tension as a potential predictor of cardiovascular events in type 2 diabetes: comparison with ankle-brachial index

OBJECTIVE

Transcutaneous oxygen tension (TcPO2) measures tissue perfusion and is important in the management of peripheral artery disease (PAD). Ankle brachial index (ABI) is used for the diagnosis of PAD and represents a predictor of major adverse cardiovascular events (MACE), even if in diabetes its diagnostic and predictive value seems to be reduced. No study has evaluated TcPO2 as a predictor of cardiovascular events. Aim of this longitudinal study was to assess whether TcPO2 is better than ABI at predicting MACE in type 2 diabetic patients.

RESEARCH DESIGN AND METHODS

Among 361 consecutive patients with apparently uncomplicated diabetes, 67 MACE occurred during a follow-up period of 45.8 ± 23.2 months.

RESULTS

The percentage of both subjects with low ABI (≤ 0.9) and subjects with low TcPO2 (≤ 46 mmHg as measured by a receiver operating characteristic curve) was significantly (<0.001) greater among patients with than among those without MACEs (ABI 64.2 vs. 40.8; TcPO2 58.2 vs. 34%). The Kaplan-Meier method showed that both low ABI (Mantel log-rank test, 4.087; P = 0.043) and low TcPO2 (Mantel log-rank test, 33.748; P > 0.0001) were associated with a higher rate of MACEs. Cox regression analysis showed that low TcPO2 (hazard ratio 1.78 [95% CI 1.44-2.23]; P < 0.001) was a significant predictor of MACE, while ABI did not enter the model.

CONCLUSIONS

This longitudinal study showed that TcPO2 may be a potential predictor of MACE among patients with uncomplicated type 2 diabetes and that its predictive value seems to be greater than that of ABI.

Efficacy of shellac, a natural product, for the prevention of wet gangrene

OBJECTIVE

To determine the effects of applying a natural polymer solution (shellac) to dry gangrene, and thereby prevent infection and progression to wet gangrene, in diabetic patients.

METHODS

This randomized, controlled, pilot study included patients with type 2 diabetes mellitus who had unreconstructable peripheral vascular disease and were awaiting autoamputation. Eligible patients were contraindicated for surgery, had a limited life expectancy and/or had refused surgical amputations. All patients received the best possible medical treatment and were randomized to receive either topical shellac or antiseptic application of 10% povidone-iodine (PVP-I) solution to gangrenous areas.

RESULTS

A total of 26 diabetic patients were eligible for inclusion, of whom 23 completed the study: 13 were treated with shellac and 10 with PVP-I. The amputation rate was higher in the conventional treatment group versus the shellac group (60.0% versus 46.2%, respectively), although this difference was not statistically significant.

CONCLUSIONS

Shellac is a natural solution that may be used to embalm gangrenous tissue in selected diabetic patients. More studies are needed to assess the long-term outcomes of this technique.

APC resistance due to Factor V Leiden is not related to baseline inflammatory mediators or survival up to 10 years in patients with critical limb ischemia

To prospectively evaluate the potential influence of resistance to activated protein C (APC-resistance) on the initial inflammatory response, amputation rate and survival during 10 years of follow-up in patients with critical limb ischemia (CLI). Two hundred and fifty-six consecutive CLI patients were analyzed for APC-ratio, the Factor V Leiden mutation and inflammatory mediators and then prospectively followed for 10 years. Inflammatory mediators, amputation rate, morbidity and mortality were compared between patients with and without APC resistance. Of the 256 CLI patients, 35 (14 %) were heterozygotes and 2 (1 %) homozygotes for the Factor V gene mutation, whereas 219 (86 %) patients were non-APC resistant. No significant differences were found between APC resistant and non-APC resistant patients regarding inflammatory mediators. Non-APC resistant patients more often had infrainguinal atherosclerosis (172 [79 %] vs 22 [59 %]; p = 0.017). Amputation rate at 1 year did not differ. Furthermore, there were no significant differences between groups regarding 1-, 3-, 5-, or 10-year survival. APC resistance in patients with CLI was not related to inflammatory activity, and had no impact on limb salvage or rate of amputation or long-term mortality. APC-resistant CLI-patients less frequently had infrainguinal arteriosclerosis, however.

Limb revascularization feasibility in diabetic patients with critical limb ischemia: results from a cohort of 344 consecutive unselected diabetic patients evaluated in 2009

AIMS

To evaluate the feasibility of peripheral revascularization by angioplasty (PTA) or bypass grafting (BPG) in diabetic patients with critical limb ischemia (CLI).

METHODS

All diabetic patients referred to our Diabetic Foot Centre for foot lesion or rest pain were assessed for the presence of CLI as assessed by the TASC criteria. All patients underwent angiography that was evaluated jointly by an interventional radiologist, a vascular surgeon and a diabetologist of the diabetic foot care team.

RESULTS

During 2009, 344 diabetics were admitted because of CLI in a total of 360 limbs. PTA was performed in 308 (85.6%) limbs, and BPG was performed in 40 (11.1%) limbs in which PTA was not feasible. Revascularization could not be carried out in 12 (3.3%) limbs due to the lack of target vessel (9 limbs) or high surgical risk (3 limbs). According to the judgement of the vascular surgeon, BPG was anatomically feasible in 180 (58.4%) of the 308 limbs that underwent PTA. Therefore, considering also the 40 limbs that underwent BPG, surgical revascularization was judged anatomically possible in a total of 220 (61.1%) limbs. At 30 days, 19 (5.3%) above-the-ankle amputations were performed: 8 (66.7%) amputations were performed in the 12 non-revascularized limbs, 8 (2.6%) amputations were performed in the 308 limbs treated with PTA and 3 (7.5%) amputations were performed in the 40 limbs treated with BPG.

CONCLUSIONS

Revascularization by PTA is highly feasible in diabetics with CLI. The feasibility of revascularization by BPG is lower but nonetheless consistent. In centres where both revascularization procedures are available, it is possible to revascularize more than 96% of diabetics with CLI.

Chapter II: Diagnostic methods

Non-invasive vascular studies can provide crucial information on the presence, location, and severity of critical limb ischaemia (CLI), as well as the initial assessment or treatment planning. Ankle-brachial index with Doppler ultrasound, despite limitations in diabetic and end-stage renal failure patients, is the first-line evaluation of CLI. In this group of patients, toe-brachial index measurement may better establish the diagnosis. Other non-invasive measurements, such as segmental limb pressure, continuous-wave Doppler analysis and pulse volume recording, are of limited accuracy. Transcutaneous oxygen pressure (TcPO(2)) measurement may be of value when rest pain and ulcerations of the foot are present. Duplex ultrasound is the most important non-invasive tool in CLI patients combining haemodynamic evaluation with imaging modality. Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) are the next imaging studies in the algorithm for CLI. Both CTA and MRA have been proven effective in aiding the decision-making of clinicians and accurate planning of intervention. The data acquired with CTA and MRA can be manipulated in a multiplanar and 3D fashion and can offer exquisite detail. CTA results are generally equivalent to MRA, and both compare favourably with contrast angiography. The individual use of different imaging modalities depends on local availability, experience, and costs. Contrast angiography represents the gold standard, provides detailed information about arterial anatomy, and is recommended when revascularisation is needed.

Chapter V: Diabetic foot

Ulcerated diabetic foot is a complex problem. Ischaemia, neuropathy and infection are the three pathological components that lead to diabetic foot complications, and they frequently occur together as an aetiologic triad. Neuropathy and ischaemia are the initiating factors, most often together as neuroischaemia, whereas infection is mostly a consequence. The role of peripheral arterial disease in diabetic foot has long been underestimated as typical ischaemic symptoms are less frequent in diabetics with ischaemia than in non-diabetics. Furthermore, the healing of a neuroischaemic ulcer is hampered by microvascular dysfunction. Therefore, the threshold for revascularising neuroischaemic ulcers should be lower than that for purely ischaemic ulcers. Previous guidelines have largely ignored these specific demands related to ulcerated neuroischaemic diabetic feet. Any diabetic foot ulcer should always be considered to have vascular impairment unless otherwise proven. Early referral, non-invasive vascular testing, imaging and intervention are crucial to improve diabetic foot ulcer healing and to prevent amputation. Timing is essential, as the window of opportunity to heal the ulcer and save the leg is easily missed. This chapter underlines the paucity of data on the best way to diagnose and treat these diabetic patients. Most of the studies dealing with neuroischaemic diabetic feet are not comparable in terms of patient populations, interventions or outcome. Therefore, there is an urgent need for a paradigm shift in diabetic foot care; that is, a new approach and classification of diabetics with vascular impairment in regard to clinical practice and research. A multidisciplinary approach needs to implemented systematically with a vascular surgeon as an integrated member. New strategies must be developed and implemented for diabetic foot patients with vascular impairment, to improve healing, to speed up healing rate and to avoid amputation, irrespective of the intervention technology chosen. Focused studies on the value of predictive tests, new treatment modalities as well as selective and targeted strategies are needed. As specific data on ulcerated neuroischaemic diabetic feet are scarce, recommendations are often of low grade.

Predicting functional status following amputation after lower extremity bypass

BACKGROUND

Some patients who undergo lower extremity bypass (LEB) for critical limb ischemia ultimately require amputation. The functional outcome achieved by these patients after amputation is not well known. Therefore, we sought to characterize the functional outcome of patients who undergo amputation after LEB, and to describe the pre- and perioperative factors associated with independent ambulation at home after lower extremity amputation.

METHODS

Within a cohort of 3,198 patients who underwent an LEB between January, 2003 and December, 2008, we studied 436 patients who subsequently received an above-knee (AK), below-knee (BK), or minor (forefoot or toe) ipsilateral or contralateral amputation. Our main outcome measure consisted of a "good functional outcome," defined as living at home and ambulating independently. We calculated univariate and multivariate associations among patient characteristics and our main outcome measure, as well as overall survival.

RESULTS

Of the 436 patients who underwent amputation within the first year following LEB, 224 of 436 (51.4%) had a minor amputation, 105 of 436 (24.1%) had a BK amputation, and 107 of 436 (24.5%) had an AK amputation. The majority of AK (75 of 107, 72.8%) and BK amputations (72 of 105, 70.6%) occurred in the setting of bypass graft thrombosis, whereas nearly all minor amputations (200 of 224, 89.7%) occurred with a patent bypass graft. By life-table analysis at 1 year, we found that the proportion of surviving patients with a good functional outcome varied by the presence and extent of amputation (proportion surviving with good functional outcome = 88% no amputation, 81% minor amputation, 55% BK amputation, and 45% AK amputation, p = 0.001). Among those analyzed at long-term follow-up, survival was slightly lower for those who had a minor amputation when compared with those who did not receive an amputation after LEB (81 vs. 88%, p = 0.02). Survival among major amputation patients did not significantly differ compared with no amputation (BK amputation 87%, p = 0.14, AK amputation 89%, p = 0.27); however, this part of the analysis was limited by its sample size (n = 212). In multivariable analysis, we found that the patients most likely to remain ambulatory and live independently despite undergoing a lower extremity amputation were those living at home preoperatively (hazard ratio [HR]: 6.8, 95% confidence interval [CI]: 0.94-49, p = 0.058) and those with preoperative statin use (HR: 1.6, 95% CI: 1.2-2.1, p = 0.003), whereas the presence of several comorbidities identified patients less likely to achieve a good functional outcome: coronary disease (HR: 0.6, 95% CI: 0.5-0.9, p = 0.003), dialysis (HR: 0.5, 95% CI: 0.3-0.9, p = 0.02), and congestive heart failure (HR: 0.5, 95% CI: 0.3-0.8, p = 0.005).

CONCLUSIONS

A postoperative amputation at any level impacts functional outcomes following LEB surgery, and the extent of amputation is directly related to the effect on functional outcome. It is possible, based on preoperative patient characteristics, to identify patients undergoing LEB who are most or least likely to achieve good functional outcomes even if a major amputation is ultimately required. These findings may assist in patient education and surgical decision making in patients who are poor candidates for lower extremity bypass.

Institutional Results and Meta-Analysis of Outcome after Infrainguinal Surgical Revascularization in Patients Greater than 80 Years Old

Our aim was to evaluate the outcome after infrainguinal bypass revascularization in patients greater than 80 years old with lower limb ischemia treated at our institution and to perform a metaanalysis of literature data to better estimate current postoperative results. Eighty-four infrainguinal bypass procedures were performed in 76 patients of at least 80 years of age. Major outcome end points included survival, limb salvage, and amputation-free survival. Systematic review and meta-analysis of literature data on immediate and late outcome in patients older than 80 years who underwent infrainguinal surgical revascularization have been performed. At 30 days, seven patients (8.3%) died and seven major amputations (8.3%) occurred. Kaplan-Meier estimates of survival at 1, 3, and 5 -years were 73.8, 59.8, and 43.1 per cent; leg salvage 78.9, 71.4, and 67.8 per cent; and amputation-free survival 58.3, 42.7, and 28.2 per cent, respectively. The mean survival was 4.6 ± 0.4 years. Only Finnvasc score greater than 2 was predictive of poor late amputation-free survival (at 5 years: 4.5 vs 42.3%; relative risk, 2.19; 95% confidence interval, 1.27 to 3.76). Eleven studies were additionally available for analysis. Pooled estimates of survival at 30 days, 1 year, and 5 years were 94.8, 86.0, and 47.6 per cent, respectively, and of leg salvage were 95.5, 84.7, and 84.1 per cent, respectively. Infrainguinal bypass in patients older than 80 years carries a significant operative risk and is associated with suboptimal long-term amputation-free survival, which is particularly poor among patients with a Finnvasc score greater than 2.

Gender differences in diabetes-related lower extremity amputations

BACKGROUND

Diabetes is a major cause of morbidity and mortality in the United States, with much of the economic and social costs related to macrovascular and microvascular complications, such as myocardial infarctions, renal failure, and lower extremity amputations. While racial/ethnic differences in diabetes are well documented, less attention has been given to differences in diabetes outcomes by gender.

QUESTIONS/PURPOSES

Does gender influence the rate of diabetes-related lower extremity amputations and/or the rate of mortality after amputation?

METHODS

I reviewed the literature utilizing peer-reviewed publications found through MEDLINE searches. WHERE ARE WE NOW?: Major complex gender differences exist in diabetes-related lower extremity amputations: men are more likely to undergo lower extremity amputations, but women apparently have higher mortality related to these procedures. The reasons for such differences are not entirely clear, but it appears biologic factors may play important roles (increased rates of peripheral vascular disease and peripheral neuropathy in men, interaction between gender and cardiac mortality in women). WHERE DO WE NEED TO GO?: More research is warranted to confirm gender differences in diabetes-related lower extremity amputation mortality and explore underlying mechanisms for the gender differences in lower extremity amputations and its associated mortality. HOW DO WE GET THERE?: Exploring gender disparities in diabetes-related outcomes, such as lower extremity amputations, will need to become a national priority from a research (eg, National Institutes of Health) and policy (eg, Centers for Medicare and Medicaid Services) perspective. Only when we have a better understanding of the causes of such differences can we begin to make strides in addressing them.