Influence of renal insufficiency on limb loss and mortality after initial lower extremity surgical revascularization

Impact of Chronic Kidney Disease on In-Hospital Outcomes of Hospitalizations With Acute Limb Ischemia Undergoing Endovascular Therapy

PURPOSE

Studies on outcomes related to endovascular treatment (EVT) in advanced stages of chronic kidney disease (CKD) and end-stage renal disease (ESRD) among hospitalizations with acute limb ischemia (ALI) are limited.

METHODS

The Nationwide Inpatient Sample was quarried from October 2015 to December 2017 to identify the hospitalizations with ALI and undergoing EVT. The study population was subdivided into 3 groups based on their CKD stages: group 1 (No CKD, stage I, stage II), group 2 (CKD stage III, stage IV), and group 3 (CKD stage V and ESRD). The primary outcome was all-cause in-hospital mortality.

RESULTS

A total of 51 995 hospitalizations with ALI undergoing EVT were identified. The in-hospital mortality was significantly higher in group 2 (OR = 1.17; 95% CI 1.04 - 1.32, p=0.009) and group 3 (OR = 3.18; 95% CI 2.74-3.69, p<0.0001) compared with group 1. Odds of minor amputation, vascular complication, atherectomy, and blood transfusion were higher among groups 2 and 3 compared with group 1. Group 2 had higher odds of access site hemorrhage compared with groups 1 and 3, whereas group 3 had higher odds of major amputation, postprocedural infection, and postoperative hemorrhage compared with groups 1 and 2. Besides, groups 2 and 3 had lower odds of discharge to home compared with group 1. Finally, the length of hospital stay and cost of care was significantly higher with the advancing CKD stages.

CONCLUSION

Advanced CKD stages and ESRD are associated with higher mortality, worse in-hospital outcomes and higher resource utilization among ALI hospitalizations undergoing EVT.

CLINICAL IMPACT

Current guidelines are not clear for the optimum first line treatment of acute limb ischemia, especially in patients with advanced kidney disease as compared to normal/mild kidney disease patients. We found that advanced kidney disease is a significant risk factor for worse in-hospital morbidity and mortality. Furthermore, patients with acute limb ischemia and advanced kidney disease is associated with significantly higher resource utilization as compared to patients with normal/mild kidney disease. This study suggests shared decision making between treating physician and patients when considering endovascular therapy for the treatment of acute limb ischemia in patients with advanced kidney disease.

Contemporary outcomes of initial treatment strategy of endovascular intervention or bypass in patients with critical limb ischemia

OBJECTIVE

The optimal management for revascularization after critical limb ischemia (CLI) is controversial due to limited studies comparing long-term results of endovascular and open techniques. This study compares long-term outcomes after initial management of CLI via lower extremity bypass (LEB) and percutaneous vascular intervention (PVI).

METHODS

This retrospective cohort study investigates outcomes of patients who underwent endovascular or open surgical management for CLI at a single institution from 2013-2018. All patients with diagnosis of CLI were included and separated based on initial therapy of PVI or LEB. Demographic, procedural, and follow-up data were assessed. Primary endpoints included major adverse limb events (MALE), specifically the need for major amputation and reintervention. Secondary endpoints included mortality at 30 days and one year. A multivariable Cox Proportional Hazard regression model was used to assess the relationship between Surgery group and time to MALE/death while controlling for confounding variables.

RESULTS

This study identified 338 patients with an initial diagnosis of CLI who underwent either LEB (n = 108, 32%) or PVI (n = 230, 68%). The average age was 71.4, 54.4% were male, 30% were African American, 53.6% were diabetic, and 93.2% had hypertension. Patients who underwent LEB were more predominantly smokers (p = .003) and less predominantly on dialysis at time of surgery (p = .01). Re-intervention rates in the bypass group (11%) were not significantly different than the PVI group (9%; p = .95). In the bypass group, 20 (19%) patients had a major amputation with a median time of 189.5 days compared to 23 (10%) patients at a median time of 113 days in the PVI group; however, this difference was not significant (p = .16). There was no significant difference in 1-year mortality between the LEB (2%) and PVI group (4%; p = .2). The cumulative incidence of MALE/death at 30 days was 4.0% in the bypass group and 3.7% in the PVI group (p = .2). Incidences of MALE/death were 21.1% and 48.5% in the bypass group and 19.7 and 45.9% in the PVI group at one and 2 years, respectively. Intervention type was not found to be significantly associated with MALE/death after controlling for possible confounders (HR = 0.82, p = .43).

CONCLUSIONS

In the initial management of CLI, there is no significant difference in long-term outcomes in terms of major amputation, need for reintervention, limb-salvage, and 1-year mortality.

Investigation of center-specific saphenous vein utilization rates in femoral popliteal artery bypass and associated impact of conduit on outcomes

OBJECTIVE

The purpose of this study is to investigate variation in great saphenous vein (GSV) use among the various centers participating in the Vascular Quality Initiative infrainguinal bypass modules. Further, differences in outcomes in femoral-popliteal artery bypass with single segment GSV conduit vs prosthetic conduit will be documented. Center GSV use rate impact on outcomes will be investigated.

METHODS

Primary exclusions were patients undergoing redo bypass, urgent or emergent bypass, and those in whom prosthetic graft was used while having undergone prior coronary artery bypass grafting. The distribution of GSV use across the 260 centers participating in Vascular Quality Initiative infrainguinal bypass module was placed into histogram and variance in mean GSV use evaluated with analysis of variance analysis. Centers that used GSV in >50% of bypasses were categorized as high use centers and centers that used the GSV in <30% of cases were categorized as low use centers. Baseline differences in patient characteristics and comorbidities in those undergoing bypass with GSV vs prosthetic conduit were analyzed with χ2 testing and the Student t test, as were those undergoing treatment in high vs low use centers. Multivariable time-dependent Cox regression analyses were then performed for the primary outcomes of major amputation ipsilateral to the operative side and mortality in long-term follow-up. High vs low use center was a dichotomous variable in these regressions. Secondary outcomes of freedom from graft infection and freedom from loss of primary patency were performed with Kaplan-Meier analysis.

RESULTS

Among centers with >50 patients meeting inclusion criteria for this study, GSV use ranged from 15% to 93% (analysis of variance P < .001). When considering all centers irrespective of number of patients, the range was 0% to 100%. On Kaplan-Meier analysis, GSV conduit use was associated with improved freedom from loss of primary or primary assisted patency, improved freedom from major amputation after index hospitalization, improved freedom from graft infection after the index hospitalization, and improved freedom from mortality in long-term follow-up (log-rank P < .001 for all four outcomes). Both low use center (hazard ratio, 1.35; P < .001) and prosthetic graft use (hazard ratio, 1.24; P < .001) achieved multivariable significance as risks for mortality in long-term follow-up. Other variables with a multivariable mortality association are presented in the manuscript. Low use center and prosthetic bypass were significant univariable but not multivariable risks for major amputation after index hospitalization.

CONCLUSIONS

There is remarkably wide variation in GSV use for femoral popliteal artery bypass among various medical centers. GSV use is associated with enhanced long-term survival as well as freedom from loss of bypass patency and graft infection. The data herein indicate institutional patterns of prosthetic conduit choice, which has the potential to be altered to enhance outcomes.

Global disease burden and its attributable risk factors of peripheral arterial disease

Peripheral arterial disease (PAD) is a prevalent subtype of atherosclerotic cardiovascular diseases. It is crucial to assess the PAD-related burden and its attributable risk factors. We use the Global Burden of Disease study 2019 database to calculate the incidence, prevalence, mortality, disability-adjusted life years (DALY), attributable risk factors and estimated annual percentage change. The disease burden of PAD grows significantly with age accompanied by prominent heterogeneity between male and female. Despite the increase in the absolute numbers of disease burden from 1990 to 2019, the global PAD-related age-standardized death rate (ASDR) and age-standardized disability-adjusted life years rate (ASDALYR) have a mild downward trend from 1990 to 2019, which negatively correlated with sociodemographic index (SDI). Smoking and high systolic blood pressure (SBP) were the primary attributable risk factors for males (ASDR: 33.4%; ASDALYR: 43.4%) and females (ASDR: 25.3%; ASDALYR: 27.6%), respectively. High fasting plasma glucose (FPG) had become the second risk factor for ASDR (males: 28.5%; females: 25.2%) and ASDALYR (males: 29.3%; females: 26.3%) with an upward tendency. Low-middle SDI regions were predicted to have the most remarkable upward trend of PAD-related burden caused by high FPG. Smoking caused more disease burden in males before 85-90 years old and females before 65-70 years old, while high FPG and high SBP caused more burden after that. The patterns of PAD-related burden and its attributable risk factors are heterogeneous across ages, genders, and SDI regions. To reduce disease burden, tailored strategies should be implemented.

Activation of the Aryl Hydrocarbon Receptor in Muscle Exacerbates Ischemic Pathology in Chronic Kidney Disease

BACKGROUND

Chronic kidney disease (CKD) accelerates the development of atherosclerosis, decreases muscle function, and increases the risk of amputation or death in patients with peripheral artery disease (PAD). However, the mechanisms underlying this pathobiology are ill-defined. Recent work has indicated that tryptophan-derived uremic solutes, which are ligands for AHR (aryl hydrocarbon receptor), are associated with limb amputation in PAD. Herein, we examined the role of AHR activation in the myopathy of PAD and CKD.

METHODS

AHR-related gene expression was evaluated in skeletal muscle obtained from mice and human PAD patients with and without CKD. AHRmKO (skeletal muscle-specific AHR knockout) mice with and without CKD were subjected to femoral artery ligation, and a battery of assessments were performed to evaluate vascular, muscle, and mitochondrial health. Single-nuclei RNA sequencing was performed to explore intercellular communication. Expression of the constitutively active AHR was used to isolate the role of AHR in mice without CKD.

RESULTS

PAD patients and mice with CKD displayed significantly higher mRNA expression of classical AHR-dependent genes (Cyp1a1, Cyp1b1, and Aldh3a1) when compared with either muscle from the PAD condition with normal renal function (P<0.05 for all 3 genes) or nonischemic controls. AHRmKO significantly improved limb perfusion recovery and arteriogenesis, preserved vasculogenic paracrine signaling from myofibers, increased muscle mass and strength, as well as enhanced mitochondrial function in an experimental model of PAD/CKD. Moreover, viral-mediated skeletal muscle-specific expression of a constitutively active AHR in mice with normal kidney function exacerbated the ischemic myopathy evidenced by smaller muscle masses, reduced contractile function, histopathology, altered vasculogenic signaling, and lower mitochondrial respiratory function.

CONCLUSIONS

These findings establish AHR activation in muscle as a pivotal regulator of the ischemic limb pathology in CKD. Further, the totality of the results provides support for testing of clinical interventions that diminish AHR signaling in these conditions.

Chronic activation of the aryl hydrocarbon receptor in muscle exacerbates ischemic pathology in chronic kidney disease

Chronic kidney disease (CKD) accelerates the development of atherosclerosis, decreases muscle function, and increases the risk of amputation or death in patients with peripheral artery disease (PAD). However, the cellular and physiological mechanisms underlying this pathobiology are ill-defined. Recent work has indicated that tryptophan-derived uremic toxins, many of which are ligands for the aryl hydrocarbon receptor (AHR), are associated with adverse limb outcomes in PAD. We hypothesized that chronic AHR activation, driven by the accumulation of tryptophan-derived uremic metabolites, may mediate the myopathic condition in the presence of CKD and PAD. Both PAD patients with CKD and mice with CKD subjected to femoral artery ligation (FAL) displayed significantly higher mRNA expression of classical AHR-dependent genes ( Cyp1a1 , Cyp1b1 , and Aldh3a1 ) when compared to either muscle from the PAD condition with normal renal function ( P <0.05 for all three genes) or non-ischemic controls. Skeletal-muscle-specific AHR deletion in mice (AHR mKO ) significantly improved limb muscle perfusion recovery and arteriogenesis, preserved vasculogenic paracrine signaling from myofibers, increased muscle mass and contractile function, as well as enhanced mitochondrial oxidative phosphorylation and respiratory capacity in an experimental model of PAD/CKD. Moreover, viral-mediated skeletal muscle-specific expression of a constitutively active AHR in mice with normal kidney function exacerbated the ischemic myopathy evidenced by smaller muscle masses, reduced contractile function, histopathology, altered vasculogenic signaling, and lower mitochondrial respiratory function. These findings establish chronic AHR activation in muscle as a pivotal regulator of the ischemic limb pathology in PAD. Further, the totality of the results provide support for testing of clinical interventions that diminish AHR signaling in these conditions.

The association of estimated glomerular filtration rate with outcomes following infrainguinal bypass for peripheral arterial disease

OBJECTIVE

Chronic kidney disease (CKD) is a recognized predictor of long-term survival, frequently coexisting with peripheral arterial disease (PAD). Estimated glomerular filtration rate (eGFR) is a more accurate marker of renal function than creatinine. This study sought to determine the graded impact of CKD, defined by eGFR, on infrainguinal lower extremity bypass (LEB) outcomes.

METHODS

This retrospective study examined 44,332 patients from the Vascular Quality Initiative database who underwent LEB between January 2003 and November 2019. The GFR was estimated using the Modification of Diet in Renal Disease equation. Multivariable logistic regression was used to study perioperative mortality and Kaplan-Meier survival estimation and multivariable Cox regression were used to evaluate 5-year mortality, 1-year major amputation, and major amputation/death.

RESULTS

The 30-day mortality odds was increased for CKD 3 (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.32-1.91; P < .001) and CKD 5 (OR, 3.08; 95% CI, 2.45-3.87; P < .001) relative to CKD 1 to 2. Comparing CKD stages 3, 4, and 5 with CKD 1 and 2, there was a stepwise increase in the adjusted hazard of 5-year mortality (hazard ratio [HR], 1.18; 95% CI, 1.09-1.27; P < .001), (HR, 1.73; 95% CI; 1.47-2.03; P < .001) and (HR, 2.58; 95% CI, 2.33-3.84; P < .001), respectively. Although the risk of 1-year death or major amputation did not differ for CKD 3 compared with CKD 1, this was 50% higher for CKD 4 (HR, 1.50; 95% CI, 1.26-1.78; P < .001) and doubled for CKD 5 (HR, 2.07; 95% CI, 1.87-2.29; P < .001) compared with CKD 1 and 2. The adjusted HR for major amputation in 1 year was 0.81 (95% CI, 0.71-0.92; P = .002), 1.14 (95% CI, 0.84-1.54; P = .396) and 1.56 (95% CI,1.31-1.84; P < .001) for CKD 3, 4, and 5, respectively, compared with CKD 1 and 2.

CONCLUSIONS

The estimated GFR is a useful predictor of postoperative mortality, overall survival, and/or amputation after LEB in patients with PAD. It should be considered in the preoperative risk-benefit analysis process to guide patient selection in the population with concomitant PAD and CKD being considered for LEB.

Clinical outcomes of patients with and without chronic kidney disease undergoing endovascular revascularization of infrainguinal peripheral artery disease: Insights from the XLPAD registry

OBJECTIVES

The purpose of the present study was to define clinical outcomes of chronic kidney disease (CKD) patients undergoing endovascular revascularization of infrainguinal peripheral artery disease (PAD).

BACKGROUND

CKD is an established predictor of advanced PAD. However, clinical outcomes for these patients following endovascular revascularization remain inadequately defined.

METHODS

Using the ongoing multicenter Excellence in Peripheral Artery Disease (XLPAD) registry (NCT01904851), we analyzed all-cause death, target limb amputation, and need for repeat revascularization for patients with and without CKD undergoing infrainguinal endovascular revascularization between the years 2005 and 2018.

RESULTS

Of 3,699 patients, 15.1% (n = 559) had baseline CKD. CKD patients had significantly higher incidence of heavily calcified lesions (48.4% vs. 38.1%, p < .001) and diffuse disease (66.9% vs. 61.5%, p = .007). Kaplan-Meier analysis showed significant differences between CKD and non-CKD patient outcomes at 12 months for freedom from target limb amputation (79.9% vs. 92.7%, p < .001) and all-cause death (90.1% vs. 97.6%, p < .001). However, freedom from target vessel revascularization was similar between the groups. After adjusting for baseline comorbidities in the CKD and non-CKD groups, the hazard ratios for target limb amputation and death at 12 months were 2.28 (95% confidence interval or CI 1.25-4.17, p < .001) and 4.38 (95% CI 2.58-7.45, p < .001), respectively.

CONCLUSIONS

Following endovascular revascularization for infrainguinal PAD, CKD was an independent predictor of all-cause death and target limb amputation at 12 months.

Indoxyl sulfate impairs angiogenesis via chronic aryl hydrocarbon receptor activation

Chronic kidney disease (CKD) is associated with a substantial increased risk of cardiovascular disease. There is growing evidence that uremic metabolites, which accumulate in the blood with CKD, have detrimental impacts on endothelial cell health and function. However, the molecular mechanisms by which uremic metabolites negatively impact endothelial cell biology are not fully understood. In this study, activation of the aryl hydrocarbon receptor (AHR) via indoxyl sulfate, a known uremic metabolite, was found to impair endothelial cell tube formation and proliferation but not migratory function. Moreover, aortic ring cultures treated with indoxyl sulfate also exhibited decreased sprouting and high AHR activation. Next, genetic knockdown of the AHR using shRNA was found to rescue endothelial cell tube formation, proliferation, and aortic ring sprouting. Similarly, pharmacological AHR antagonism using resveratrol and CH223191 were also found to rescue angiogenesis in cell and aortic ring cultures. Finally, a constitutively active AHR (CAAHR) vector was generated and used to confirm AHR-specific effects. Expression of the CAAHR recapitulated the impaired tube formation and proliferation in cultured endothelial cells and decreased sprouting in aortic ring cultures. Taken together, these data define the impact of AHR activation on angiogenesis and highlight the potential for therapeutic AHR antagonists, which may improve angiogenesis in the context of CKD and cardiovascular disease.

Early outcomes of patients with chronic kidney disease after revascularization for critical limb ischemia

BACKGROUND

The aim of this study was to report early outcomes of patients with non-dialysis-dependent chronic kidney disease (NDD-CKD) after revascularization for critical limb-threatening ischemia (CLTI).

METHODS

Perioperative data of patients from the CRITISCH (critical limb ischemia) Registry, who also had NDD-CKD (stages 3 and 4), were compared to their counterparts with normal renal function (NRF) or mild renal insufficiency (stages 1 and 2). Patient characteristics and type of first-line treatment were assessed. Amputation-free survival was the primary composite endpoint. Secondary endpoints included major adverse cardiovascular and cerebral events (MACCE) and hemodynamic failure of revascularization. Multivariable logistic regression determined risk factors for the endpoints.

RESULTS

424 patients with NDD-CKD were identified. Endovascular revascularization (ER) was performed in 251 patients (59.2%). Eighty-six patients (20.3%) underwent bypass surgery (BS) and 29 patients (6.8%) femoral artery patchplasty (FAP). Conservative treatment (CT) was offered to 46 patients (10.9%); 12 patients (2.8%) underwent primary major amputation (PMA). Logistic regression analysis showed an increased early risk for amputation/death (OR=1.92, 95% CI: 1.09-3.40), death (OR=5.53, 95% CI: 1.92-15.90) and hemodynamic failure of the revascularization (OR=1.80, 95% CI: 1.19-2.72) compared to patients with NRF. Patients with NDD-CKD also seem to carry a higher risk for MACCE (OR=1.82, 95% CI: 0.99-3.36). NDD-CKD was not a risk factor for limb loss alone (OR=1.05, 95% CI: 0.49-2.22).

CONCLUSIONS

NDD-CKD was an independent risk factor for early postoperative mortality, morbidity and reduced patency, but not for limb loss. Robust follow-up is necessary to monitor for such events, as well as to prevent readmission.

Influence of end-stage renal disease on long-term survival after major amputation

Background: To analyze long-term outcomes and possible influencing factors in patients with endstage renal disease (ESRD) and critical limb ischemia (CLI) after major amputation compared to patients with normal renal function and non-dialysis-dependent chronic kidney disease. Patients and methods: Abstraction of single-center medical records of patients undergoing above knee (AKA) and below knee (BKA) amputation over a 10 years period (n = 436; 2009-2018). Excluded were amputations due to trauma or tumor. Patients were subdivided according to renal function in three categories: ESRD patients (n = 98), non-dialysis dependent chronic kidney disease (CKD, n = 98) and normal renal function (NF, n = 240). Predefined endpoints were survival and postoperative complications. Cox-regression models were built to analyze independent risk factors for outcome parameters. Results: In total, 298 AKA, 133 BKA and 5 knee joint exarticulations were performed. ESRD patients showed inferior in-hospital results as to death (ESRD 36.7 % vs. CKD 19.4 % and NF 20.0 %, P = .002). Similarly, long-term survival rates (6 months: ESRD 55.0 % vs. CKD 69.4 %, NF 67.9 % 1 year: ESRD 48.6 %, CKD 60.2 %, NF 60.8 % 5 years: ESRD 9.9 %, CKD 31.8 %, NF 37.1 %, P < .001) were significantly decreased for ESRD patients. Median postoperative survival was 10 months in ERSD, and 22 months in CKD and NF, respectively. Analysis of postoperative surgical complications revealed no differences between groups (ESRD 19.4 %, CKD 17.3 %, NF 17.0 %; P = 0.433). Cox regression analysis indicated that dialysis (HR 1.63; 95 % CI 1.22-2.16; P = .001), hypertension (HR 1.59; 95 % CI 0.99-2.54) and smoking (HR 1.22; 95 % CI 1.03-1.44; P = .022) was associated with increased risk of death during follow-up. Conclusions: Mortality after limb amputation in ERSD patients remains high. Survival of ERSD patients is lower in relation to chronic kidney disease and patients with normal renal function. Due to poor in hospital outcomes and absent long-term survival, benefit of primary amputation in ERSD seems scarce.

Chronic kidney disease exacerbates ischemic limb myopathy in mice via altered mitochondrial energetics

Chronic kidney disease (CKD) substantially increases the severity of peripheral arterial disease (PAD) symptomology, however, the biological mechanisms remain unclear. The objective herein was to determine the impact of CKD on PAD pathology in mice. C57BL6/J mice were subjected to a diet-induced model of CKD by delivery of adenine for six weeks. CKD was confirmed by measurements of glomerular filtration rate, blood urea nitrogen, and kidney histopathology. Mice with CKD displayed lower muscle force production and greater ischemic lesions in the tibialis anterior muscle (78.1 ± 14.5% vs. 2.5 ± 0.5% in control mice, P < 0.0001, N = 5-10/group) and decreased myofiber size (1661 ± 134 μm2 vs. 2221 ± 100 μm2 in control mice, P < 0.01, N = 5-10/group). This skeletal myopathy occurred despite normal capillary density (516 ± 59 vs. 466 ± 45 capillaries/20x field of view) and limb perfusion. CKD mice displayed a ~50-65% reduction in muscle mitochondrial respiratory capacity in ischemic muscle, whereas control mice had normal mitochondrial function. Hydrogen peroxide emission was modestly higher in the ischemic muscle of CKD mice, which coincided with decreased oxidant buffering. Exposure of cultured myotubes to CKD serum resulted in myotube atrophy and elevated oxidative stress, which were attenuated by mitochondrial-targeted therapies. Taken together, these findings suggest that mitochondrial impairments caused by CKD contribute to the exacerbation of ischemic pathology.

Different association between renal dysfunction and clinical outcomes according to the presence of diabetes in patients undergoing endovascular treatment for peripheral artery disease

OBJECTIVE

Although chronic kidney disease (CKD) and diabetes are important prognostic factors in patients with peripheral artery disease, there are limited data regarding the outcomes of endovascular treatment (EVT) according to the severity of CKD, especially in the presence of diabetes. This study sought to compare clinical outcomes of lower limb EVT between patients with and patients without CKD according to the presence of diabetes.

METHODS

Patients were enrolled from the Korean multicenter EVT registry and were divided according to the presence of diabetes, then further stratified by CKD (estimated glomerular filtration rate <60 mL/min/1.73 m²). The primary outcome was major adverse limb events (MALEs; a composite of reintervention for target limb, reintervention for target vessel, and unplanned major amputation) at 2 years.

RESULTS

A total of 3045 patients were eligible for analysis: 1277 nondiabetic patients (944 without CKD, 333 with CKD) and 1768 diabetic patients (951 without CKD, 817 with CKD). CKD was associated with a significantly increased risk of MALEs after EVT in diabetic patients (14.4% vs 9.9%; adjusted hazard ratio, 1.60; 95% confidence interval, 1.28-2.01; P < .001) but not in nondiabetic patients (7.6% vs 9.7%; adjusted hazard ratio, 0.78; 95% confidence interval, 0.53-1.14; P = .203; interaction P = .018). In analysis stratified by the severity of CKD among diabetic patients, end-stage renal disease was significantly associated with an increased risk of MALE.

CONCLUSIONS

CKD was associated with a significantly higher risk of MALEs after EVT in diabetic patients but not in nondiabetic patients. The increased risk of MALEs was mainly driven by patients with end-stage renal disease.

Factors Associated with Wound Complications after Open Femoral Artery Exposure for Elective Endovascular Abdominal Aortic Aneurysm Repair

We identified factors that would lead to wound complications after open femoral exposure for endovascular abdominal aortic aneurysm repair (oEVAR). Using the National Surgical Quality Improvement Program dataset (2005-2014), we examined the patients who underwent oEVAR. Patients were stratified on whether they developed postoperative wound complications. Comparisons were made between group with wound complications and those without and adjusted analyses performed to identify variables that independently increased the risk of wound complications. There were 14,868 patients in the study cohort and 2.6% (384 patients) developed wound complications after EVAR. Among those with wound complications, 94% (360 patients) of patients had superficial and deep surgical site infection. Patients who had wound complication were likely to be younger (72.6 vs. 73.7 years old ( p  = 0.02), functionally dependent (5.4 vs. 2.5%) ( p  < 0.05), smoker (3 vs. 2.4%, p =0.03), female (4 vs. 2.2%), with significantly higher body mass index (31 vs. 28), and more commonly had diabetes (4 vs. 2.4%, p  < 0.001) or renal failure (12 vs. 3%, p  < 0.001). Although perioperative survival was similar, patients who had wound complications had significantly longer hospital length of stay (LOS) (7.3 ± 12 vs. 3.4 ± 5 days, p  < 0.001). Up to 3% patients developed wound complications after open femoral exposure during EVAR with significantly higher LOS and therefore cost utilization.

Unique aspects of peripheral artery disease in patients with chronic kidney disease

Peripheral artery disease (PAD) represents a major health care burden. Despite the advent of screening and interventional procedures, the long-term clinical outcomes remain suboptimal, especially in patients with chronic kidney disease (CKD). While CKD and PAD share common predisposing factors, emerging studies indicate that their co-existence is not merely an association; instead, CKD represents a strong, independent risk factor for PAD. These findings implicate CKD-specific mediators of PAD that remain incompletely understood. Moreover, there is a need to understand the mechanisms underlying poor outcomes after interventions for PAD in CKD. This review discusses unique clinical aspects of PAD in patients with CKD, including high prevalence and worse outcomes after vascular interventions and the influence of renal allograft transplantation. In doing so, it also highlights underappreciated aspects of PAD in patients with CKD, such as disparities in revascularization and higher peri-procedural mortality. While previous reviews have discussed general mechanisms of PAD pathogenesis, focusing on PAD in CKD, this review underscores a need to probe for CKD-specific pathogenic pathways that may unravel novel biomarkers and therapeutic targets in PAD and ultimately improve the risk stratification and management of patients with CKD and PAD.

Editor's Choice - Comparison of Outcomes After Open Surgical and Endovascular Lower Extremity Revascularisation Among End Stage Renal Disease Patients on Dialysis

OBJECTIVES

End stage renal disease (ESRD) patients with peripheral arterial disease (PAD) are at high risk of complications following open surgical revascularisation (OSR). Endovascular revascularisation (ER) is an option, but its role is unclear. This study sought to characterise the outcomes of ER and OSR in ESRD patients treated for claudication or critical limb ischaemia (CLI).

METHODS

The United States Renal Data System was used to investigate outcomes after lower extremity ER and OSR from 2005 to 2011. Primary outcomes were mortality, amputation, and peri-procedural myocardial infarction (MI). Kaplan-Meier (K-M) estimates were generated for mortality and amputation, logistic regression models for 30 day predictors, and proportional hazards models for long-term predictors.

RESULTS

A total of 20,347 patients underwent OSR and ER (20.3% OSR, 79.7% ER). CLI was the indication in 80.8% of ER and 88.4% of OSR. The unadjusted major amputation rate at 30 days was higher after ER compared with OSR (8.8% vs. 6.4%, p < .001). Conversely, the unadjusted mortality rate at 30 days was lower after ER compared with OSR (8.0% vs. 10.5%, p < .001). Multivariable logistic regression models adjusting for medical covariables and CLI versus claudication status demonstrated increased 30 day mortality risk with OSR compared with ER (OR 2.00, 95% CI 1.43-1.79, p < .001), MI (OR 1.38, 1.23-1.54, p < .001), and the combined endpoint of mortality and major amputation (OR 1.57, 1.16-2.12, p = .004), but lower odds of 30 day major amputation alone (OR 0.67, 0.58-0.77, p < .001). Proportional hazards models demonstrated increased long-term mortality risk with OSR compared with ER (HR 1.05, 1.00-1.09, p = .037), without a difference in major amputation (HR 0.99, 0.93-1.05, p = NS).

CONCLUSIONS

In this retrospective analysis of an administrative database, ESRD patients suffer from high mortality and amputation rates following lower extremity revascularisation. Compared with ER, OSR is associated with higher mortality. OSR has better 30 day limb salvage, although long-term outcomes are similar.

Morbidity in parathyroid surgery for renal disease is under reported: a comparison of outcomes with primary hyperparathyroidism

Introduction Parathyroidectomy is considered to be a safe procedure with low morbidity. However, while this is true for primary hyperparathyroidism, whether it applies to tertiary disease is not so well documented. The aim of this study was to assess the morbidity of surgery for tertiary hyperparathyroidism compared with primary disease and to establish whether there are predictive factors for poor outcomes. Methods Data for patients subjected to parathyroidectomy during the period 2007-2015 were retrospectively analysed from a prospectively collected database. Patient age, sex, American Society of Anesthesiologists (ASA) score, renal status, extent of operation and indications for surgery were examined. The complication and mortality rate were compared and independent predictors of outcome were examined. Results A total of 1079 patients were scheduled for a parathyroidectomy during the study period of whom 158 for renal related hyperparathyroidism (renal group) and 921 for primary disease (non-renal group). There was a significantly higher complication rate in the renal parathyroid group, including a higher mortality (1.3% vs 0.1%, P = 0.011), overall complication rate (7.0% vs 2.3%, P = 0.001), surgery related complication rate (4.4% vs 1.7%, P = 0.03) and systemic complication rate (2.5% vs 0.4%, P = 0.005). In patients with ASA score ≤ 2 reoperative surgery (OR 9.25, 95% confidence interval, CI 1.41-60.75), male sex (OR 4.12, 95% CI 1.46-11.63) and renal impairment were (OR 5.86, 95% CI 1.65-20.78) were predictors of worse outcomes. In patients with ASA score ≥3 renal impairment, in addition to other variables, were not predictors of complications. Conclusions Parathyroidectomy in renal-related disease is associated with a significantly higher risk of morbidity and mortality compared with primary hyperparathyroidism.

Predictors of early mortality and readmissions among dialysis patients undergoing lower extremity amputation

OBJECTIVE

Patients receiving dialysis are at increased risk for lower extremity amputations (LEAs) and postoperative morbidity. Limited studies have examined differences in 30-day outcomes of mortality and health care use after amputation or the preoperative factors that relate to worsened outcomes in dialysis patients. Our objective was to examine dialysis dependency and other preoperative factors associated with readmission or death after LEA.

METHODS

A retrospective cohort study was conducted of dialysis-dependent and nondialysis patients undergoing major LEA in the 2012 to 2013 American College of Surgeons National Surgical Quality Improvement Program. Primary outcomes included death and hospital readmission within 30 days of amputation.

RESULTS

Of 6468 patients, 1166 (18%) were dialysis dependent. The dialysis cohort had more blacks (39% vs 23%), diabetes (76% vs 58%), below-knee amputations (62% vs 55%), and in-hospital deaths (8% vs 3%; all P < .001). The 30-day postoperative death rates (15% vs 7%) and readmission rates (35% vs 20% per 30 person-days; both P < .001) were higher in dialysis patients. Among the live discharges, the rate of any readmission or death within 30 days from amputation was highest in those aged ≥50 years (40% per 30 person-days). Multivariable analyses in the dialysis cohort revealed increased age, above-knee amputation, decreased physical status, heart failure, high preoperative white blood cell count, and low platelet count to be associated with death (P < .05; C statistic, 0.75). The only preoperative factor associated with readmission in dialysis patients was race (P = .04; C statistic, 0.58).

CONCLUSIONS

Readmission or death after amputation is increased among dialysis patients. Predicting which dialysis patients are at highest risk for death is feasible, whereas predicting which will require readmission is less so. Risk factor identification may improve risk stratification, inform reimbursement policies, and allow targeted interventions to improve outcomes.

Predictors of delayed wound healing after successful isolated below-the-knee endovascular intervention in patients with ischemic foot ulcers

OBJECTIVE

The purpose of this study was to explore the predictors of delayed wound healing and their use in risk stratification for endovascular treatment (EVT) of patients with critical limb ischemia (CLI) due to isolated below-the-knee lesions.

METHODS

Wound healing rates were analyzed retrospectively in patients who underwent successful below-the-knee percutaneous transluminal balloon angioplasty for CLI with tissue loss between May 2008 and June 2013. We also analyzed the independent predictors of delayed wound healing and their use in risk stratification.

RESULTS

The cumulative wound healing rates were 13.9%, 43.8%, 57.7%, and 65.7% at 3, 6, 9, and 12 months, respectively. Multivariate Cox proportional hazards analysis revealed the following as independent predictors of wound nonhealing after initial successful EVT: patients with end-stage renal disease receiving dialysis (hazard ratio [HR], 2.6; 95% confidence interval [CI], 1.0-6.3; P  = .04); albumin level <3.0 g/dL (HR, 2.0; 95% CI, 1.1-3.8; P  = .02); C-reactive protein level >5.0 mg/dL (HR, 3.9; 95% CI, 1.6-9.6; P = .003); major tissue loss (HR, 2.1; 95% CI, 1.3-3.4; P = .003); wound infection (HR, 1.9; 95% CI, 1.2-2.9; P = .005); gangrene (HR, 1.8; 95% CI, 1.2-2.8; P = .008); wound depth (University of Texas grade 3; HR, 3.4; 95% CI, 1.4-8.6; P = .009); duration of ulcer (≥2 months; HR, 2.9; 95% CI, 1.0-8.4; P = .048); insulin use (HR, 1.7; 95% CI, 1.0-2.8; P = .04); and lack of below-the-ankle runoff (HR, 1.9; 95% CI, 1.0-3.4; P = .04).

CONCLUSIONS

The general status of the patient and the target limb's condition are important predictors of wound nonhealing. Regarding the limb's condition, information on wound depth and duration in addition to wound extent and infection would further enable the selection of suitable CLI patients for EVT. Such information would also enable optimal wound management, leading to successful wound healing and improved limb salvage and survival rates.

Nationwide Trends in Hospital Outcomes and Utilization After Lower Limb Revascularization in Patients on Hemodialysis

OBJECTIVES

This study aimed to describe the temporal trends and outcomes of endovascular and surgical revascularization in a large, nationally representative sample of patients with end-stage renal disease on hemodialysis hospitalized for peripheral artery disease (PAD).

BACKGROUND

PAD is prevalent among patients with end-stage renal disease on hemodialysis and is associated with significant morbidity and mortality. There is a paucity of information on trends in endovascular and surgical revascularization and post-procedure outcomes in this population.

METHODS

We used the Nationwide Inpatient Sample (2002 to 2012) to identify hemodialysis patients undergoing endovascular or surgical procedures for PAD using diagnostic and procedural codes. We compared trends in amputation, post-procedure complications, mortality, length of stay, and costs between the 2 groups using trend tests and logistic regression.

RESULTS

There were 77,049 endovascular and 29,556 surgical procedures for PAD in hemodialysis patients. Trend analysis showed that endovascular procedures increased by nearly 3-fold, whereas there was a reciprocal decrease in surgical revascularization. Post-procedure complication rates were relatively stable in persons undergoing endovascular procedures but nearly doubled in those undergoing surgery. Surgery was associated with 1.8 times adjusted odds (95% confidence interval: 1.60 to 2.02) for complications and 1.6 times the adjusted odds for amputations (95% confidence interval: 1.40 to 1.75) but had similar mortality (adjusted odds ratio: 1.05; 95% confidence interval: 0.85 to 1.29) compared with endovascular procedures. Length of stay for endovascular procedures remained stable, whereas a decrease was seen for surgical procedures. Overall costs increased marginally for both procedures.

CONCLUSIONS

Rates of endovascular procedures have increased, whereas those of surgeries have decreased. Surgical revascularization is associated with higher odds of overall complications. Further prospective studies and clinical trials are required to analyze the relationship between the severity of PAD and the revascularization strategy chosen.

Effects of chronic kidney disease on clinical outcomes in patients with peripheral artery disease undergoing endovascular treatment: Analysis from the K-VIS ELLA registry

OBJECTIVES

Chronic kidney disease (CKD) is a risk factor for peripheral artery disease (PAD), but the impact of CKD in PAD patients who received endovascular treatment (EVT) is not well studied. Aim of this study is to clarify the impact of CKD in patients with PAD in real EVT era.

METHODS

Using the Korean Vascular Intervention Society (K-VIS) endovascular therapy in lower limb artery disease registry (ELLA) registry, we analyzed 3434 patients who underwent EVT. Baseline characteristics, in-hospital events, and overall- and major adverse limb events (MALE)-free survival were analyzed.

RESULTS

2739 patients (3548 target limbs) were included. 272 patients featured CKD (9.9%). Limbs in CKD patients had higher Rutherford scores, higher prevalence of critical limb ischemia (CLI). There were no differences in technical success rates in non-CKD vs. CKD group comparison and non-severe CKD vs. severe CKD group comparison (p = 0.050, 0.581, respectively). In-hospital death (p < 0.001) and short-term unexpected amputation (p = 0.028) were more frequent in the CKD group. The short-term outcome differences between severe and non-severe CKD were insignificant. Kaplan-Meier curves favored overall and MALE-free survival in non-CKD patients compared with CKD patients, but there was no difference in overall- or MALE-free survival between non-severe CKD and severe CKD groups.

CONCLUSION

PAD patients with CKD showed worse short-term mortality, short-term unexpected amputation outcome, and overall- and MALE-free survival than those without CKD in real EVT era. These findings might provide additive prognostic information for PAD patients with CKD who will be treated with EVT.

Patency of the arterial pedal-plantar arch in patients with chronic kidney disease or diabetes mellitus

BACKGROUND

Patency of the pedal-plantar arch limits risk of amputation in peripheral artery disease (PAD). We examined patients without chronic kidney disease (CKD)/diabetes mellits (DM) [PAD-control], those with DM without CKD, and those with CKD without DM.

METHOD

Uni- and multivariate logistic regression was used to assess association of CKD with loss of patency of the pedal-plantar arch and presence of tibial or peroneal vessel occlusion. Multivariate models adjusted for age, sex, hypertension, hyperlipidemia and smoking.

RESULTS

A total of 419 patients were included [age 75.2 ± 10.3 years, 288 (69%) male]. CKD nearly doubled the unadjusted odds ratio (OR) for loss of patency of the pedal-plantar arch. After adjustment, association remained significant for severe CKD [estimated glomerular filtration rate (eGFR) ≤ 29 ml/min compared with eGFR ≥ 60 ml/min, adjusted (adj.) OR 8.24 (95% confidence interval {CI} 0.99-68.36, p = 0.05)]. CKD was not related to risk of tibial or peroneal artery occlusion [PAD-control versus CKD, adj. OR 1.09 (95% CI 0.49-2.44, p = 0.83)] in contrast to DM [PAD-control versus DM, adj. OR 2.41 (95% CI 1.23-4.72, p = 0.01), CKD versus DM, adj. OR 2.21 (95% CI 0.93-5.22); p = 0.07)].

CONCLUSIONS

Below the knee (BTK) vascular pattern differs in patients with either DM or CKD alone. Severe CKD is a risk factor for loss of patency of the pedal-plantar arch.

Clinical Outcomes after Isolated Infrapopliteal Revascularization in Hemodialysis Patients with Critical Limb Ischemia: Endovascular Therapy versus Bypass Surgery

AIM

To investigate the long-term clinical outcome of endovascular therapy (EVT) or bypass surgery in patients on hemodialysis (HD) with critical limb ischemia due to isolated infrapopliteal disease.

METHODS

We enrolled 254 consecutive HD patients successfully undergoing infrapopliteal revascularization by EVT (126 patients) and bypass surgery (128 patients). They were followed up for five years. Amputation-free survival (AFS) and incidence of any re-intervention were evaluated. A propensity score from all baseline variables was incorporated into Cox analysis.

RESULTS

In the EVT group, age was higher (p=0.039), diabetes and coronary artery disease were more frequent (p=0.004 and p=0.0052, respectively), and tissue loss was more rarely observed (p＜ 0.0001) than in the bypass group. During the follow-up period, 21 major amputations and 64 deaths occurred. The propensity score-adjusted AFS rate at 5 years was comparable between groups (61.0% in EVT group vs. 55.1% in the bypass group, adjusted hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.52-1.42, p=0.58). The adjusted survival rates were also similar between groups for amputation and all-cause mortality. However, freedom from any re-intervention was markedly lower in the EVT than in the bypass group (48.6% vs. 84.6%, adjusted-HR, 3.56, 95% CI 1.95-6.75, p＜ 0.0001).

CONCLUSIONS

The rate of AFS was broadly comparable between the two strategies, although compared with bypass surgery, EVT had much higher rates for re-intervention.

Outcomes of Isolated Tibial Endovascular Intervention for Rest Pain in Patients on Dialysis

BACKGROUND

Tibial interventions for critical limb ischemia are frequent in patients with end-stage renal disease (ESRD) presenting with critical ischemia. The aim of this study was to examine impact of ESRD on the patient-centered outcomes following tibial endovascular Intervention for rest pain.

METHODS

A database of patients undergoing lower extremity endovascular interventions between 2006 and 2016 was retrospectively queried. Patients with rest pain (Rutherford 4) were identified. Patients with claudication (Rutherford 1 to 3) and tissue loss (Rutherford 5 and 6) were excluded. Patients were categorized by the presence or absence of ESRD. Patient-orientated outcomes of clinical efficacy (CE; absence of recurrent symptoms, maintenance of ambulation, and absence of major amputation), amputation-free survival (AFS; survival without major amputation), and freedom from major adverse limb events (MALEs; above ankle amputation of the index limb or major reintervention new bypass graft, jump/interposition graft revision) were evaluated.

RESULTS

A total of 829 patients (56% male, average age 59 years; 658 nonhemodialysis [non-HD] and 171 HD) underwent isolated tibial intervention in one leg for rest pain. Technical success was 99% with a median of 2 vessels treated per patient. There was no difference in the distribution of Trans-Atlantic Inter-Society Consensus I lesions, but both the modified Society for Vascular Surgery (SVS) runoff score and the pedal runoff score were worse in the HD group. The 30-day major adverse cardiac events and 30-day MALEs were equivalent in both groups. CE was 38 ± 9% and 19 ± 8% at 5 years for the non-HD and HD groups, respectively (P < 0.01). Overall, AFS was 45 ± 8% and 18 ± 9% at 5 years for the non-HD and HD groups, respectively (P < 0.01). Freedom from MALE was 41 ± 9% and 21 ± 8% at 5 years for the non-HD and HD groups, respectively (P < 0.01).

CONCLUSIONS

Patients with ESRD who present with rest pain have equivalent short-term outcomes to those not on dialysis but do not achieve long-term satisfactory CE and AFS after isolated tibial intervention for rest pain.

Results for primary bypass versus primary angioplasty/stent for lower extremity chronic limb-threatening ischemia

BACKGROUND

Long-term results comparing percutaneous transluminal angioplasty with or without stenting (PTA/S) and open surgical bypass for chronic limb-threatening ischemia (CLTI) in patients who have had no prior intervention are lacking.

METHODS

All patients undergoing a first-time lower extremity revascularization for CLTI by vascular surgeons at our institution from 2005 to 2014 were retrospectively reviewed. Outcomes included perioperative complications, wound healing, restenosis, primary patency, reintervention, major amputation, RAS events (ie, reintervention, major amputation, or stenosis), and mortality. Outcomes were evaluated using χ², Kaplan-Meier, and Cox regression analyses.

RESULTS

Of the 2869 total lower extremity revascularizations performed between 2005 and 2014, there were 1336 that fit our criteria of a first-time lower extremity intervention for CLTI (668 bypass procedures and 668 PTA/S procedures). Bypass patients were younger (71 vs 72 years; P = .02) and more often male (62% vs 56%; P < .02). Total mean hospital length of stay (LOS) was significantly longer after a first-time bypass (10 vs 8 days; P < .001), as were mean preoperative LOS (4 vs 3 days; P < .01) and postoperative LOS (7 vs 5 days; P < .001). There was no difference in perioperative mortality (3% vs 3%; P = .63). Surgical site infection occurred in 10% of bypass patients. Freedom from reintervention was significantly higher in patients undergoing a first-time bypass procedure (62% vs 52% at 3 years; P = .04), as was freedom from restenosis (61% vs 45% at 3 years; P < .001). Complete wound healing at 6-month follow-up was significantly better after an initial bypass (43% vs 36%; P < .01). A Cox regression model of all patients showed that reintervention was predicted by a first-time PTA/S (hazard ratio, 1.6; 95% confidence interval, 1.3-2.1) and both preoperative femoropopliteal TransAtlantic Inter-Society Consensus (TASC) C and TASC D lesions (2.0 [1.3-3.1] and 1.8 [1.3-2.7], respectively). Major amputation among all patients was predicted by an initial presentation of gangrene (2.5 [1.3-5.0]), dialysis dependence (1.9 [1.3-2.9]), diabetes (2.0 [1.1-3.8]), and preoperative femoropopliteal TASC D lesions (2.1 [1.1-4.0]) and was not predicted by procedure type.

CONCLUSIONS

In this retrospective analysis, bypass for the primary treatment of CLTI showed improved 6-month wound healing, higher freedom from restenosis, improved patency rates, significantly fewer reinterventions, and higher survival than PTA/S within 3 years; however, a bypass-first approach was associated with increased total hospital LOS and wound infection. Perioperative mortality and amputation rates were similar between procedure types.

Wound healing of critical limb ischemia with tissue loss in patients on hemodialysis

We assessed wound healing in patients on hemodialysis (HD) with critical limb ischemia (CLI). This study enrolled 267 patients (including 120 patients on HD and 147 patients not on HD) who underwent endovascular therapy (EVT) for CLI. The primary endpoint was wound-healing rate at two years. Secondary endpoints were time to wound healing, wound recurrence rate, and limb salvage at two years. The percentage of male and young patients was higher in the HD patients ( p < 0.01). A lower patency of the pedal arch after EVT was observed frequently in HD patients ( p < 0.01). The wound-healing rate was significantly lower in HD patients (79.5% vs. 92.4%, p < 0.001). Time to wound healing was significantly longer in HD patients (median 132 days vs. 82 days, p = 0.005). Wound recurrence was observed more frequently in HD patients (25.0% vs. 10.2%, p = 0.007). Limb salvage (72.8% vs. 86.4%, p = 0.002) was significantly lower in HD patients. In a cox proportional hazard model, HD was an independent predictor of wound healing (risk ratio (RR), 0.46; 95% confidence interval (CI), 0.33-0.62; p < 0.001) and wound recurrence (RR, 1.58; 95% CI, 1.11-2.22; p = 0.01). HD was independently associated with lower and delayed wound healing, and wound recurrence.

A Comparison of the Regional Circulation in the Feet between Dialysis and Non-Dialysis Patients using Indocyanine Green Angiography

BACKGROUND AND AIMS

Peripheral artery disease in dialysis cases is more prone to critical limb ischemia compared to non-dialysis cases, with a significantly high rate of major amputation of the lower limbs. Lesions are distributed on the more distal side in dialysis critical limb ischemia cases. The aim of this study was to investigate the usefulness of indocyanine green angiography to determine differences in the regional circulation in the foot between dialysis and non-dialysis patients.

MATERIALS AND METHODS

The subjects included 62 cases, among which 20 were dialysis patients and 42 were non-dialysis patients. We compared the indocyanine green angiography parameters for regions of interest in the dialysis and non-dialysis groups, which included the magnitude of intensity from indocyanine green onset to maximum intensity (Imax), the time from indocyanine green onset to maximum intensity (Tmax), the time elapsed from the fluorescence onset to half the maximum intensity (T1/2), and the time from maximum intensity to declining to 90% of the maximum intensity (Td90%). These indocyanine green angiography parameters were measured at region of interest 1 (the Chopart joint), region of interest 2 (the Lisfranc joint), and region of interest 3 (the distal region of the first metatarsal bone).

RESULTS

In the comparison between the dialysis and non-dialysis groups, a significant difference was observed regarding Tmax, T1/2, and Td90%, especially in region of interest 3.

CONCLUSION

In this study, we show that regional tissue perfusion is more deteriorated in dialysis patients compared with non-dialysis patients using indocyanine green angiography. Tmax, T1/2, and Td90% could be useful clinical parameters to compare ischemic severity of the lower limb between dialysis and non-dialysis patients.

Relation of Baseline Renal Dysfunction With Outcomes in Patients Undergoing Popliteal and Infrapopliteal Percutaneous Peripheral Arterial Interventions

Renal dysfunction is a major risk factor for peripheral arterial disease (PAD). Infrapopliteal PAD is associated with more co-morbid conditions and worse prognosis than suprapopliteal PAD. Long-term outcomes of patients with renal dysfunction and popliteal or infrapopliteal PAD undergoing peripheral vascular intervention (PVI) are not well described. We retrospectively evaluated long-term outcomes in 726 patients undergoing infrapopliteal PVI categorized into 3 glomerular filtration rate (GFR)-based groups: GFR (≥60 ml/min/1.73 m(2)), GFR (<60 ml/min/1.73 m(2)), and those on dialysis. At mean follow-up of 36 ± 20 months, amputation rates were 3%, 5%, and 11% with mortality rates of 23%, 36%, and 56% in normal renal function, chronic kidney disease (adjusted odds ratio [OR] for amputation 1.75, 95% CI 0.73 to 4.21; adjusted OR for mortality 1.53, 95% CI 1.05 to 2.23, p = 0.028), and dialysis (adjusted OR for amputation 2.43, 95% CI 0.84 to 7.02, p = 0.100; adjusted OR for mortality 4.51, 95% CI 2.46 to 8.26, p <0.0001) groups, respectively. Repeat revascularization was similar in all 3 groups at roughly 25%. In conclusion, chronic kidney disease and dialysis were associated with increased major amputations and mortality in patients who received PVI for popliteal and infrapopliteal PAD.

[Lower limb peripheral arterial disease in 268 patients in Guadeloupe]

Peripheral arterial disease of the lower limbs is a serious condition because of its local and general prognosis.

OBJECTIVES

To identify the localization of peripheral arterial disease, associated risk factors, topography and features of the disease in Guadeloupe.

PATIENTS AND METHODS

A descriptive non-interventional study was performed in Guadeloupe located in French West Indies from March to June 2014. Data for all patients, who underwent Doppler ultrasound of the lower limb in a vascular outpatient clinic and in the University Hospital in Guadeloupe for known or suspected peripheral arterial disease were included.

RESULTS

The study included 268 patients. Localizations were: infrapopliteal (n=227 patients), popliteal (n=148), femoral (n=185) and aorto-iliac (n=115). Smoking was associated with aorto-iliac (16 patients; P<0.05) and femoral (27 patients; P<0.05) localizations. Diabetes was associated with infrapopliteal localizations (133 patients; P<0.05), and high blood pressure was associated with infrapopliteal, popliteal and femoral localizations. Mean age was 73.1±10.8 years; half of patients (51 %) were women. Peripheral arterial disease was known for 52 % of the population; 147 patients were asymptomatic. Associated factors were high blood pressure (88 %), diabetes (63 %), dyslipidemia (45 %), and smoking (7 %). Ischemic heart disease was found in 14 % of patients, cerebrovascular disease in 18 % and all three localizations in 4 %. A history of amputation, bypass or endovascular treatment was found in 11 %, 20 % and 32 % of patients respectively.

CONCLUSION

In our population, an infrapopliteal site was more often found than a proximal site. Distal localization was associated with diabetes, and proximal localization with smoking. Cardiovascular risk factors exhibited an atypical pattern with a large majority of patients (88 %) having high blood pressure, two-thirds diabetes, but with very few (7 %) smokers. Peripheral arterial disease was more often associated with a history of stroke than with ischemic heart disease.

CKD and Acute and Long-Term Outcome of Patients with Peripheral Artery Disease and Critical Limb Ischemia

BACKGROUND AND OBJECTIVES

Despite the many studies showing an association between CKD and a high risk of ischemic events and mortality, the association of CKD with peripheral arterial disease (PAD) still has not been well described.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This large cohort study assessed the association of CKD, even in the earlier stages, with morbidity, short- and long-term outcome, and costs among patients with PAD.

RESULTS

We identified 41,882 patients with PAD who had an index hospitalization between January 1, 2009, and December 31, 2011. Of these, 8470 (20.2%) also had CKD (CKD stage 2: n=2158 [26%]; stage 3: n=3941 [47%]; stage 4: n=935 [11%]; stage 5: n=1436 [17%]). The ratio of women to men was 1:1.2. Compared with patients without known CKD, those with CKD had higher frequencies of coronary artery disease (1.8-fold higher; P<0.001), chronic heart failure (3.3-fold higher; P<0.001), and Rutherford PAD categories 5 and 6 (1.8-fold higher; P<0.001); underwent significantly fewer revascularizations (0.9-fold fewer; P<0.001); had a nearly two-fold higher amputation rate (P<0.001); had higher frequencies of in-hospital infections (2.1-fold higher; P<0.001), acute renal failure (2.8-fold higher; P<0.001), and sepsis (1.9-fold higher; P<0.001); had a 2.5-fold higher frequency of myocardial infarction (P<0.001); and had a nearly three-fold higher in-hospital mortality rate (P<0.001). In an adjusted multivariable Cox regression model, CKD remained a significant predictor of long-term outcome of patients with PAD during follow-up for up to 4 years (until December 31, 2012; median, 775 days; 25th-75th percentiles, 469-1120 days); the hazard ratio was 2.59 (95% confidence interval, 2.21 to 2.78; P<0.001). The projected mortality rates after 4 years were 27% in patients without known CKD and 46%, 52%, 72%, and 78% in those with CKD stages 2, 3, 4, and 5, respectively. Lengths of hospital stay and reimbursement costs were on average nearly 1.4-fold higher (P<0.001) in patients who also had CKD.

CONCLUSIONS

This analysis illustrates the significant and important association of CKD with in-hospital and long-term mortality, morbidity, amputation rates, duration and costs of hospitalization, in-hospital treatment, and complications in patients with PAD.

Outcomes of Isolated Tibial Endovascular Interventions for Tissue Loss in CLI Patients on Hemodialysis

PURPOSE

To compare the objective performance goals (OPGs) and patient-centered outcomes of isolated tibial interventions in patients with tissue loss who were on hemodialysis (HD) to patients with tissue loss who were not on HD.

METHODS

Interrogation of a prospectively maintained database identified 242 critical limb ischemia (CLI) patients who underwent isolated tibial interventions for tissue loss in a single limb between 2007 and 2012. The 78 patients (mean age 66±12 years; 44 men) on HD were compared with 164 patients (mean age 50±13 years; 82 men) who were not on HD. There was an equal distribution of the tibial vessels treated; 152 (63%) patients had more than one treated tibial vessel. Patient-centered outcomes of clinical efficacy (absence of recurrent symptoms, maintenance of ambulation, and no major amputation), amputation-free survival (AFS), and freedom from major adverse limb events (MALE) were evaluated. The Society for Vascular Surgery OPGs were defined at 30 days and 1 year.

RESULTS

The 30-day major adverse cardiac events was significantly higher (p=0.004) in the HD group (5, 5%) compared with the no-HD group (0%), but both remained under the stated OPG of ≤10%. The 30-day MALE rates were significantly higher than the stated ≤9% OPG at 13% and 18% for the no-HD and HD groups, respectively. At 1 year, the rates for AFS, freedom from MALE, limb salvage, and survival did not achieve the stated Society for Vascular Surgery OPGs in the HD group. Clinical efficacy was 61% and 25% at 3 years for the no-HD and HD groups, respectively (p<0.01). Overall, AFS was 54% and 22% and freedom from MALE was 56% and 27% at 3 years for the no-HD and HD groups, respectively (both p<0.01).

CONCLUSION

Tibial intervention for tissue loss in patients on HD is a valid treatment option but is associated with a high MALE rate. Three-year outcomes remain relatively poor, with <25% success in terms of clinical efficacy and AFS.

Epidemiology of peripheral artery disease

New data on the epidemiology of peripheral artery disease (PAD) are available, and they should be integrated with previous data. We provide an updated, integrated overview of the epidemiology of PAD, a focused literature review was conducted on the epidemiology of PAD. The PAD results were grouped into symptoms, diagnosis, prevalence, and incidence both in the United States and globally, risk factors, progression, coprevalence with other atherosclerotic disease, and association with incident cardiovascular morbidity and mortality. The most common symptom of PAD is intermittent claudication, but noninvasive measures, such as the ankle-brachial index, show that asymptomatic PAD is several times more common in the population than intermittent claudication. PAD prevalence and incidence are both sharply age-related, rising >10% among patients in their 60s and 70s. With aging of the global population, it seems likely that PAD will be increasingly common in the future. Prevalence seems to be higher among men than women for more severe or symptomatic disease. The major risk factors for PAD are similar to those for coronary and cerebrovascular disease, with some differences in the relative importance of factors. Smoking is a particularly strong risk factor for PAD, as is diabetes mellitus, and several newer risk markers have shown independent associations with PAD. PAD is strongly associated with concomitant coronary and cerebrovascular diseases. After adjustment for known cardiovascular disease risk factors, PAD is associated with an increased risk of incident coronary and cerebrovascular disease morbidity and mortality.

Prognostic Factors in Hemodialysis Patients Undergoing Endovascular Treatment for Critical Limb Ischemia due to Isolated Below-the-Knee Disease

AIM

To investigate the prognosis and to clarify the predictors of both patient and limb survival among hemodialysis (HD) patients with critical limb ischemia (CLI) due to isolated below-the-knee (BK) disease.

METHODS

An observational cohort study, analyzing a total of 546 HD patients with 681 limbs who underwent endovascular treatment (EVT) for CLI with isolated BK disease at 11 hospitals in Japan between March 2004 and June 2011, was performed.

RESULTS

The mean patient age was 69.0±9.5 years, and 420 (76.9%) of the subjects were men. The number of patients classified with Rutherford stage 4, 5 and 6 disease was 103 (18.9%), 332 (60.8%) and 111 (20.3%), respectively. The mean HbA1c level was 6.48±1.20%, and 195 (35.7%) of the subjects were active smokers. During the follow-up period (mean: 557.5 days), 191 (35.0%) patients died and 82 (12.0%) limbs underwent major amputation. The freedom from all-cause death was 75.5%, 53.4% and 36.9% and freedom from major amputation was 86.7%, 83.9% and 83.9% at one, three and five years after EVT, respectively. Cox proportional hazard regression analyses revealed that a non-ambulatory status, low serum albumin level and ＜2 runoff vessels after EVT were significant predictors for both all-cause death and major amputation.

CONCLUSIONS

Although patient survival remains poor, the limb salvage rate after EVT is favorable among those on HD with CLI due to isolated BK disease. The present results allow for the risk stratification of HD patients with CLI undergoing EVT for isolated BK disease.

Efficacy of revascularization for critical limb ischemia in patients with end-stage renal disease

OBJECTIVE

To evaluate the outcomes of surgical revascularization for critical limb ischemia in patients with end-stage renal disease (ESRD).

PATIENTS AND METHODS

From 2004 to 2010, 184 patients with 213 critically ischaemic limbs caused by arteriosclerosis were admitted to The University of Tokyo Hospital. The outcomes of primarily surgical revascularization-based treatments were retrospectively compared in patients with ESRD (ESRD group: 79 patients, 101 limbs) and without ESRD (non-ESRD group: 105 patients, 112 limbs) during the same period.

RESULTS

Arterial reconstruction was performed on 56 limbs in 46 patients in the ESRD group and 78 limbs in 73 patients in the non-ESRD group (55% vs. 70%; p = .03). Major amputation was performed in 6 of 48 limbs with patent grafts in the ESRD group because of uncontrolled infection or progression of necrosis. The limb salvage rate after arterial reconstruction was significantly lower in the ESRD group than in the non-ESRD group (p = .0019). The postoperative survival rate was lower in the ESRD group than in the non-ESRD group, although this difference was not significant (p = .052). Associated cardiovascular disease and systemic infection were the most frequent causes of death in the ESRD group. There was no significant difference in graft patency between the two groups after distal bypass surgery; however, the limb salvage rate was significantly lower in the ESRD group than in the non-ESRD group (p = .03).

CONCLUSIONS

Critical limb ischemia associated with ESRD has a poor prognosis. Infection control is particularly important for achievement of good treatment outcomes.

A retrospective review of leg wound complications after coronary artery bypass surgery

Little research or attention has been paid to finding out whether wound closure with sutures or staples attains the best outcomes after saphenous vein harvest for coronary artery bypass grafting. We undertook a quality improvement project to compare the prevalence of leg wound complications (eg, infection, seroma, hematoma, dehiscence) between two types of skin closure (ie, staples, subcuticular sutures) after conventional open surgery with bridging between incisions and vein harvesting during coronary revascularization to determine the need for practice changes. We found no significant differences between patients with wound complications and those without. However, in this project, the risk for infections was greater for patients with diabetes whose wounds were closed by using subcuticular sutures. These findings have led to practice changes for reducing leg wound complications within our institution: clinicians now assess patients for increased risk of leg wound complications preoperatively and opt to close wounds with staples for patients who have diabetes.