Detection of peripheral artery disease by duplex ultrasonography among hemodialysis patients

The Double Burden: Deciphering Chronic Limb-Threatening Ischemia in End-Stage Renal Disease

BACKGROUND

Chronic limb-threatening ischemia (CLTI) in patients with end-stage renal disease (ESRD) poses significant challenges in clinical management due to its unique pathology and poor treatment outcomes. This review calls for a tailored classification and risk assessment for these patients to guide better revascularization choices with early minor amputation as a first-line strategy in advanced stages.

METHODS

This review consolidates key findings from recent literature on CLTI in ESRD, focusing on disease mechanisms, treatment options, and patient outcomes. It evaluates the literature to clarify the decision-making process for managing CLTI in ESRD.

RESULTS

CLTI in ESRD patients often results in worse clinical outcomes, such as nonhealing wounds, increased limb loss, and higher mortality rates. While the literature reveals ongoing debates regarding the optimal revascularization method, recent retrospective studies and meta-analyses suggest potential benefits of endovascular treatment (EVT) over open bypass surgery (OB) in reducing mortality and wound complications, with comparable amputation-free survival rates.

CONCLUSIONS

The selection of revascularization methods in ESRD patients with CLTI is complex, necessitating individualized strategies. The importance of early detection and timely intervention is critical to decelerate disease progression and improve revascularization outcomes. There is a shift in these treatment strategies toward less invasive endovascular procedures, acknowledging the limitations these patients face with open revascularization surgeries. Considering early minor amputations after revascularization could prevent worse consequences, reflecting a shift in the approach to managing CLTI in ESRD patients.

Prosthesis use and the change in activities of daily living following below-knee amputation in patients undergoing hemodialysis

INTRODUCTION

Patients undergoing hemodialysis are at an increased risk of peripheral arterial disease, amputation of lower extremities, and decline of activities of daily living. Although a prosthesis is used to support activities of daily living, no previous study reported the association of prosthesis use with the change in activities of daily living following leg amputation in hemodialysis patients. The purpose of this study was to compare the changes in activities of daily living following amputation between those who created a prosthesis and those who did not.

METHODS

This study was a single-center, retrospective observational study. We screened medical records for hemodialysis patients who underwent below-knee amputation (BKA) and activities of daily living were examined two times with the functional independence measure (FIM) before BKA and at discharge. They were divided into two groups according to the creation of a prosthesis.

FINDINGS

We identified 28 eligible patients, among whom 12 patients used a prosthesis (prosthesis group), whereas 16 patients did not (non-prosthesis group). The FIM score was significantly decreased following BKA in the non-prosthesis group, whereas it was not significantly changed in the prosthesis group. The change in FIM score was significantly different between the two groups, and the difference remained significant after considering potential confounders.

DISCUSSION

The results of this study showed that use versus nonuse of a prosthesis was an independent factor associated with changes in activities of daily living in hemodialysis patients following BKA, supporting the important role of a prosthesis in maintaining activities of daily living in hemodialysis patients who need BKA.

Clinical Characteristics of the Patient With Unmeasurable Ankle-Brachial Index in Endovascular Treatment

Introduction Ankle-brachial index (ABI) is an important indicator to diagnose lower extremity arterial disease (LEAD). However, patients with unmeasurable ABI are sometimes excluded from the analysis and their clinical characteristics are poorly understood. Methods One hundred twenty-two consecutive Japanese subjects (mean age, 72 years), who underwent successful endovascular treatment (EVT) for lower extremity arteries at our hospital were retrospectively studied. Results Of the 122 patients, 23 (19%) patients presented an unmeasurable ABI before EVT. Five of 23 (22%) had still an unmeasurable ABI one day after EVT. Comorbidities including hypertension, diabetes, dyslipidemia, hemodialysis, smoking, ischemic heart disease, atrial fibrillation, and past-EVT history were not different between ABI measurable and unmeasurable patients. However, patients with unmeasurable ABI presented a significantly higher degree of Rutherford category and a smaller number of tibial vessel runoff than patients with measurable ABI before EVT (p<0.05 and p<0.01, respectively). There was no difference in the lesion site between the two groups. The event rate including all-cause mortality, re-EVT, lower limb amputation, and bypass surgery did not differ between two groups four years after EVT. ABI after four years of initial EVT did not differ between pre-EVT measurable and unmeasurable patients (0.96 vs. 0.84, p=0.48). Conclusions Patients with unmeasurable ABI before EVT were characterized by higher degree of Rutherford categorization and a small number of tibial vessel runoff, but there was no significant difference in outcomes during the follow-up period.

Prevalence and Predictors of Peripheral Vascular Disease Amongst Predialysis Hypertensive Chronic Kidney Disease Patients in Southern Nigeria

BACKGROUND

Peripheral vascular disease (PVD) is an atherosclerotic disease associated with increased morbidity and mortality among chronic kidney disease (CKD) patients. However, despite the substantial burden of PVD in CKD, local data are lacking.

OBJECTIVE

To determine the prevalence and predictors of PVD in predialysis CKD patients.

METHOD AND MATERIALS

The study was cross-sectional. One hundred fifty hypertensive CKD patients and age- and sex-matched hypertensive non-CKD subjects were consecutively enrolled at the renal unit of Delta State University Teaching Hospital (DELSUTH), Oghara. Structured questionnaires were used to obtain information on participants' demographic data and health status. PVD was defined by an ankle-brachial index of < 0.9 or > 1.4 in either lower extremity. eGFR was calculated from serum creatinine using the MDRD equation.

RESULTS

The mean ages of the study and control groups were 48±14 and 51±15years, respectively. The sex ratio was 3:2 in favour of males for both the study and control groups. The majority of the study group was in CKD stage 4 (44%). The prevalence of PVD was higher among the CKD group compared with controls (24.0% vs. 14.7%). Of the CKD patients with PVD, 11.1% were symptomatic. Predictors of PVD in the study group were eGFR (B=0.010, 95%CI: 0.007-0.013), diastolic BP (B=-0.005, 95%CI: -0.007- -0.002), MAP (B=-0.018, 95%CI: -0.027- -0.008), urinary ACR (B=-0.0036, 95%CI: -0.040- -0.024) and smoking history (p<0.001, OR=14.71).

CONCLUSION AND RECOMMENDATION

PVD is common and largely asymptomatic in CKD patients. The predictors of PVD in this study were eGFR, diastolic BP, mean arterial pressure (MAP), urinary albumin to creatinine ratio (ACR), and smoking. A proactive assessment of PVD and early intervention in CKD patients is needed.

Risks and outcomes of critical limb ischemia in hemodialysis patients: a prospective cohort study

Background

Peripheral arterial disease (PAD) is more common in patients receiving maintenance hemodialysis than in the general population. Critical limb ischemia (CLI), the most severe form of PAD, is associated with high amputation and mortality risk. However, few prospective studies are available evaluating this disease's presentation, risk factors and outcomes for patients receiving hemodialysis.

Methods

The Hsinchu VA study, a prospective multicentre study, investigated the impact of clinical factors on cardiovascular outcomes of patients receiving maintenance hemodialysis from January 2008 until December 2021. We evaluated the presentations and outcomes of patients with newly diagnosed PAD and the correlations of clinical variables with newly diagnosed CLI.

Results

Of 1136 study participants, 1038 had no PAD on enrolment. After a median follow-up period of 3.3 years, 128 had newly diagnosed PAD. Of these, 65 presented with CLI, and 25 underwent amputation or died from PAD. Patients presenting with CLI had more below-the-knee (52%) and multi-level (41%) disease, and completely occluded segments (41%), and higher risk for amputation or PAD-related death compared with patients without CLI (27.7% vs 9.5%, P = .01). After multivariate adjustment, disability, diabetes mellitus, current smoking and atrial fibrillation were significantly associated with newly diagnosed CLI.

Conclusions

Patients undergoing hemodialysis had higher rates of newly diagnosed CLI than the general population. Those with disabilities, diabetes mellitus, smoking and atrial fibrillation may require careful examination for PAD. Trial registration: Hsinchu VA study, ClinicalTrials.gov identifier: NCT04692636.

Renin-Angiotensin-Aldosterone System (RAS) Inhibitors May Suppress the Prevalence of Peripheral Arterial Disease (PAD) in Elderly, Chronic Hemodialysis Patients

According to the hypertension guidelines, calcium antagonists are recommended as antihypertensive drugs for Stage 5 of chronic kidney disease (CKDG5) and late elderly patients, whereas renin-angiotensin-aldosterone system (RAS) inhibitors (RASi) are not recommended. We screened elderly CKDG5D patients at a single outpatient maintenance hemodialysis center for the progression of peripheral arterial disease (PAD) using the ankle-brachial index (ABI) and skin perfusion pressure (SPP) tests, as well as logistic regression analysis, to determine the association between PAD and the treatment with RASi and the association between the treatment with RASi and the need for hospitalization within one year of observation. With the presence of PAD as the explanatory variable and the presence of RASi as the objective variable, the odds ratio was 1.23 (95% confidence interval [CI] 0.37 to 3.82) in univariate analysis. After adjusting for confounding factors (age, gender, and hypertension), the odds ratio in multivariate analysis was 0.83 (95% CI 0.46 to 6.08). The presence or absence of PAD was significantly associated with an odds ratio of 3.24 (p = .04, 95% CI 1.0 to 10.25) and 4.63 (p = .026, 95% CI 1.20 to 17.84) in univariate and multivariate analyses, respectively, when the outcome was hospitalization at one year, regardless of the presence or absence of RASi. However, in univariate analysis, the odds ratio was 1.23 (95% CI 0.37 to 3.82) with RASi status as the explanatory variable and one-year hospitalization as the objective variable. After adjusting for confounders, the odds ratio in multivariate analysis was 0.83 (95% CI 0.46 to 6.08). Although further large-scale, multicenter studies are needed to establish the evidence, our results suggest that RASi treatment may have a suppressive effect on the prevalence of PAD and the need for hospitalization in elderly CKDG5 dialysis (CKDG5D) patients.

A prognostic risk score for major amputation in dialysis patients with chronic limb-threatening ischemia after endovascular revascularization

BACKGROUND

Almost 38% of all patients with end-stage chronic kidney disease (CKD) have peripheral arterial disease of the lower limbs that can lead to chronic limb threatening ischemia (CLTI). The aim of this study was to assess the impact of several factors to conduct a stratification of the amputation risk in CKD patients with CLTI receiving endovascular revascularization.

METHODS

Observational, retrospective, single-center study of patients treated from 2010 to 2016. The primary endpoint was the major amputation. The study included adult CKD dialysis patients affected by CLTI (rest pain and/or trophic lesions) with indication to endovascular revascularization and excluded for open repair.

RESULTS

A total of 82 patients were considered (58 men [70.7%], 24 women [29.3%] mean age 70.4±15.0 years). The number of major amputations was 28 (34.1%). The arterial lesion severity (TASC II-classification) and the trophic lesions extension (WIfI classification) were significantly associated with major amputation (OR and 95%CI, 1.20 [1.07-1.34], P=0.001; 2.65 [1.49-4.72], P=0.001; respectively). Based on the above-mentioned characteristics, a prognostic score was proposed to predict the major amputation risk. A score ≥23 was associated with a 67.6% probability of amputation in the following 12 months.

CONCLUSIONS

The CLTI revascularization is associated with poor outcomes in CKD patients. The present clinical score provided a pragmatic tool to calculate the major amputation risk. An elevated score could facilitate the decision-making process in order to perform an endovascular treatment vs. conservative approach.

Prognostic Significance of Abnormal Ankle-Brachial Index Among Long-term Hemodialysis Patients in Kinshasa, the Democratic Republic of the Congo

OBJECTIVE

Early identification of atherosclerosis using a non-invasive tool like ankle-brachial index (ABI) could help reduce the risk for cardiovascular disease among long-term hemodialysis patients. The study objective was to assess the frequency and impact of abnormal ABI as a marker of subclinical peripheral artery disease (PAD) in chronic hemodialysis patients.

METHODS

This was a historic cohort study of kidney failure patients on long-term hemodialysis for at least 6 months. The ABI, measured with two oscillometric blood pressure devices simultaneously, was used to assess subclinical atherosclerosis of low limb extremities. Abnormal ABI was defined as ABI <0.9 or >1.3 (PAD present). Survival was defined as time to death. Independent factors associated with abnormal ABI were assessed using multiple logistic regression analysis. Kaplan-Meier method (log-rank test) was used to compare cumulative survival between the two groups; a P value <0.05 was statistically significant.

RESULTS

Abnormal ABI was noted in 50.6% (n=43) of the 85 kidney failure patients included in the study; 42.4% (n=36) had a low ABI, and 8.2% (n=7) had a high ABI. Factors associated with PAD present were cholesterol (adjusted odds ratio [AOR], 1.02; 95% confidence interval [CI], 1.01-1.04; P=0.019), inflammation (AOR, 9.44; 95% CI, 2.30-18.77; P=0.002), phosphocalcic product (AOR, 6.25; 95% CI, 1.19-12.87; P=0.031), and cardiac arrhythmias (AOR, 3.78; 95% CI, 1.55-7.81, P=0.009). Cumulative survival was worse among patients with PAD present (log-rank; P=0.032).

CONCLUSION

The presence of PAD was a common finding in the present study, and associated with both traditional and emerging cardiovascular risk factors as well as a worse survival rate than patients without PAD.

Indoxyl Sulfate and Incident Peripheral Artery Disease in Hemodialysis Patients

Peripheral artery disease (PAD) is highly prevalent among patients with chronic kidney disease (CKD) and portends a very poor prognosis. Indoxyl sulfate has been shown to induce atherothrombosis and impaired neovascularization in uremic mice. However, there is no clinical evidence regarding the role of indoxyl sulfate in PAD associated with CKD. We examined associations between indoxyl sulfate and incident symptomatic lower extremity PAD events as well as major adverse cardiovascular events (MACE) and all-cause mortality using Cox proportional hazards models in a prospective cohort of 200 hemodialysis patients free of PAD at baseline. Patients were considered as having PAD if they developed PAD symptoms confirmed by an ankle-brachial index with waveforms, duplex ultrasound or angiography, and/or major adverse limb events including revascularization and amputation. During a median follow-up of 6.5 years, 37 patients (18.5%) experienced incident symptomatic PAD. MACE occurred in 52 patients, and a total of 85 patients died. After adjusting for traditional risk factors for PAD, including age, current smoking, diabetes, and cardiovascular disease, indoxyl sulfate was significantly associated with the risk of PAD (hazard ratio (HR), 1.19 for every 10-μg/mL increase in indoxyl sulfate; 95% confidence interval (CI), 1.05–1.35). However, indoxyl sulfate was not associated with risk of MACE (HR, 1.00; 95% CI, 0.90–1.12) or death from any cause (HR, 0.98; 95% CI, 0.90–1.07). Indoxyl sulfate was associated with incident symptomatic PAD but not with MACE or all-cause mortality, suggesting that indoxyl sulfate toxicity may be unique to PAD among hemodialysis patients.

Pole Test and Ankle-Brachial Index by Using Doppler Ultrasound for Peripheral Arterial Disease in End-Stage Renal Disease Patients

Peripheral arterial disease (PAD) causes great disability in end-stage renal disease (ESRD). Pole test is a simplified test utilizing the basis of Doppler ultrasound invented to correct false elevation in ankle-brachial index (ABI) in diabetic patients with severe calcification of the tibial artery. However, the role of pole test in ESRD patients is still unclear. The aim of this study was to explore the sensitivity, specificity, and overall utility of pole tests in such patients. One hundred and four patients were recruited and examined with 3 tests: pole test, ABI, and toe-brachial index, the latter serving as the gold standard. Receiver operating characteristic analysis was performed using SPSS version 22.0. The sensitivity, specificity, and other diagnostic values of ABI and pole tests were calculated. There were 104 ESRD patients enrolled. Pole tests showed to have low probability to provide accurate results (area under the curve = 0.505, standard error = 0.042). Low sensitivity of ABI (34.96%) can be observed in ESRD patients. Specificity, positive predictive value, and negative predictive value of ABI in all cases were, respectively, 85.91%, 81.13%, and 43.26%. It is concluded that pole test accuracy seemed to be limited in ESRD patients. ABI was found to be confounded by medial arterial calcification, resulting in low sensitivity as well. The results of this study permit the observation that an optimal tool for screening peripheral arterial disease in ESRD patients remains to be discovered.

Laser Doppler blood flowmeter as a useful instrument for the early detection of lower extremity peripheral arterial disease in hemodialysis patients: an observational study

BACKGROUND

A simpler method for detecting atherosclerosis obliterans is required in the clinical setting. Laser Doppler flowmetry (LDF) is easy to perform and can accurately detect deterioration in skin perfusion. We performed LDF for hemodialysis patients to determine the correlations between blood flow in the lower limbs and peripheral arterial disease (PAD).

METHODS

This retrospective study included 128 hemodialysis patients. Patients were categorized into the non-PAD group (n = 106) and PAD group (n = 22), 14 early stage PAD patients were included in the PAD group. We conducted LDF for the plantar area and dorsal area of the foot and examined skin perfusion pressure (SPP) during dialysis.

RESULTS

SPP-Dorsal Area values were 82.1 ± 22.0 mmHg in the non-PAD, and 59.1 ± 20.3 mmHg in PAD group, respectively (p < 0.05). The LDF-Plantar blood flow (Qb) values were 32.7 ± 15.5 mL/min in non-PAD group and 21.5 ± 11.3 mL/min in PAD group (p < 0.001). A total of 21 non-PAD patients underwent LDF before and during dialysis. The LDF-Plantar-Qb values were 36.5 ± 17.6 mL/min before dialysis and 29.6 ± 17.7 mL/min after dialysis (p < 0.05). We adjusted SPP and LDF for PAD using logistic regression, SPP-Dorsal-Area and LDF-P were significantly correlated with PAD (p < 0.05). The receiver-operating characteristic curve analysis indicated cut-off values of 20.0 mL/min for LDF-Plantar-Qb during dialysis.

CONCLUSION

LDF is a simple technique for sensitive detection of early-stage PAD. This assessment will help physicians identify early-stage PAD, including Fontaine stage II in clinical practice, thereby allowing prompt treatment.

Prevalence, clinical characteristics, and predictors of peripheral arterial disease in hemodialysis patients: a cross-sectional study

Background

Peripheral arterial disease (PAD) is common in patients with end-stage renal disease on hemodialysis, but is frequently underdiagnosed. The risk factors for PAD are well known within the general population, but they differ somewhat in hemodialysis patients. This study aimed to determine the prevalence of PAD and its risk factors in patients on hemodialysis.

Methods

This cross-sectional study included 156 hemodialysis patients. Comorbidities and laboratory parameters were analyzed. Following clinical examinations, the ankle-brachial index was measured in all patients. PAD was diagnosed based on the clinical findings, ankle-brachial index < 0.9, and PAD symptoms.

Results

PAD was present in 55 of 156 (35.3%; 95% CI, 27.7–42.8%) patients. The patients with PAD were significantly older (67 ± 10 years vs. 62 ± 11 years, p = 0.014), more likely to have diabetes mellitus (p = 0.022), and anemia (p = 0.042), and had significantly lower serum albumin (p = 0.005), total cholesterol (p = 0.024), and iron (p = 0.004) levels, higher glucose (p = 0.002) and C-reactive protein (p < 0.001) levels, and lower dialysis adequacies (p = 0.040) than the patients without PAD. Multivariate analysis showed higher C-reactive protein level (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.00–1.06; p = 0.030), vascular access by Hickman catheter (OR, 4.66; 95% CI, 1.03–21.0; p = 0.045), and symptoms of PAD (OR, 5.20; 95% CI, 2.60–10.4; p < 0.001) as independent factors associated with PAD in hemodialysis patients.

Conclusion

The prevalence of PAD was high among patients with end-stage renal disease on hemodialysis. Symptoms of PAD, higher C-reactive protein levels, and Hickman vascular access were independent predictors of PAD in patients on hemodialysis.

Carotid intima-media thickness and plaques in internal carotid artery as surrogate markers of lower limb arterial lesions in Chinese patients with diabetic foot

Peripheral arterial disease (PAD) can impair healing of diabetic foot (DF) in patients with diabetes mellitus. To determine whether carotid intima-media thickness (CIMT) can predict lower limb arterial lesions in patients with DF, this cross-sectional study enrolled patients with DF at West China Hospital (China) between January 2012 and December 2015. Ultrasonography was used to measure CIMT, assess the internal carotid arteries (ICA) for plaques, and evaluate lower limb segmental arteries for stenosis. The optimal CIMT cutoff for detecting lower limb PAD was determined by receiver operating characteristic (ROC) curve analysis. Factors associated with PAD were identified by logistic regression analyses. A total of 167 patients (mean age: 69.7±10.3 years; 102 men) were included. Patients with PAD were older and had higher levels of total cholesterol and low-density lipoprotein than patients without PAD (P<0.05). The area under the ROC curve was 0.747 (P<0.001). At the optimal CIMT cutoff of 0.71 mm, the sensitivity, specificity, positive predictive value, and negative predictive value were 79.65, 61.11, 81.08, and 58.93%, respectively. Compared with those without PAD, more patients with PAD had CIMT ≥0.71 mm (79.65 vs 38.89%; P<0.001) and ICA plaques (66.37vs 11.11%; P<0.001). Multivariate logistic regression revealed that age (odds ratio [OR]: 1.118; 95% confidence interval [95%CI]: 1.056–1.183; P<0.001), ICA plaques (OR: 13.452; 95%CI: 4.450–40.662; P<0.001), and CIMT ≥0.71 mm (OR: 2.802; 95%CI: 1.092–7.188; P=0.032) were associated with PAD.CIMT may be a surrogate marker of PAD in patients with DF.

Brachial-ankle pulse wave velocity, cardio-ankle vascular index, and prognosis

Background

Brachial–ankle pulse wave velocity (baPWV) and cardio-ankle vascular index (CAVI) are indices of arterial stiffness, and several studies have used these indices. However, there is no comprehensive review of these parameters in the prognostic significance.

Methods

The aim of this study was to review the articles exploring the prognostic significance of these parameters. Articles demonstrating independent significance after multivariate analysis on the Cox proportional hazards model were defined as “successful.” The success rate was compared using Fisher’s exact test. In addition, multivariate logistic regression analysis was performed to explore the independent determinants of the success of prognostic prediction.

Results

The success rate of the baPWV articles (65.7% [46/70]) tended to be higher than that of the CAVI articles (40.0% [6/15]; P=0.083). Multivariate analysis demonstrated that log (number of patients) (OR 11.20, 95% CI 2.45–51.70, P=0.002) and dialysis population (OR 0.28, 95% CI 0.08–0.94, P=0.039) were positive and negative independent determinants of the success of prognostic prediction, respectively. In addition, after redefining two studies as the absence of arteriosclerosis obliterans (ASO) exclusion, baPWV (OR 3.36, 95% CI 0.86–13.20, P=0.083) and the existence of exclusion criteria of ASO (OR 3.08, 95% CI 0.96–9.93, P=0.060) exhibited statistical tendency in the multivariate analysis.

Conclusion

This study demonstrated that the number of study participants and dialysis population were the independent determinants of the success of prognostic prediction. This study also showed the importance of exclusion criteria of ASO when using these indices. In addition, a prospective large-scale study to confirm the superiority in the prognostic prediction of these indices is warranted.

Pitfalls in the ankle-brachial index and brachial-ankle pulse wave velocity

Background

The ankle-brachial index (ABI) and pulse wave velocity (PWV) are indices of atherosclerosis and arterial stiffness. The Japan-made measuring devices of those indices have spread widely because of their convenience and the significance of the parameters. However, studies that comprehensively discuss the various pitfalls in using these indices are not available.

Methods

This study presents several representative pitfalls in using the ABI and brachial-ankle PWV (baPWV) by showing the result sheets of the device, “the Vascular Profiler”. Furthermore, some considerations when utilizing these indices in the future are also discussed.

Results

Several diseases such as arteriosclerosis obliterans (ASO), arterial calcification in the lower limb, arterial stenosis in the right upper-limb, aortic valve diseases, arterial stenosis in the upper-limb of the contralateral side of the hemodialysis access, are the representative pitfalls when evaluating ABI and baPWV. Moreover, a measurement error is found to actually exist. Furthermore, same phenomena are considered most likely to occur when using other similar indices and devices.

Conclusion

The ABI and baPWV are the useful and significant biomarkers. Nevertheless, caution is sometimes necessary when interpreting them. Moreover, rigorous patient exclusion criteria should be considered when using those indices in the severely conditioned patient population. And the results of this study can be applied to enhance the literacy using other indices, such as the cardio-ankle vascular index and other similar devices.

Electronegative low-density lipoprotein increases the risk of ischemic lower-extremity peripheral artery disease in uremia patients on maintenance hemodialysis

Electronegative low-density lipoprotein (LDL) has been shown to increase coronary artery disease risk in hemodialysis patients, but its effect on the risk of peripheral artery disease (PAD) remains unclear. We separated plasma LDL from 90 uremia patients undergoing hemodialysis into 5 subfractions (L1-L5) according to charge by using fast-protein liquid chromatography with an anion-exchange column and examined the distribution of L5-the most electronegative LDL subfraction-in total LDL (i.e. L5%). During a 5-year period, we followed up with these patients until the occurrence of ischemic lower-extremity PAD. During the follow-up period, ischemic lower-extremity PAD developed in 24.4% of hemodialysis patients. L5% was higher in hemodialysis patients in whom ischemic lower-extremity PAD occurred (3.03% [IQR, 2.36-4.54], n = 22) than in hemodialysis patients in whom PAD did not occur (1.13% [IQR, 0.90-1.83], n = 68) (p < 0.001). Furthermore, L5% significantly increased the adjusted hazard ratio of ischemic lower-extremity PAD (1.54 [95% CI, 1.14-2.10]) (p = 0.005). Flow-mediated dilation was negatively associated with L5% (p < 0.001). Additionally, in vivo experiments from mice showed that L5 compromised endothelium-dependent vascular relaxation through a nitric oxide-related mechanism. Our findings indicate that increased L5% may be associated with the occurrence of ischemic lower-extremity PAD in hemodialysis patients.

Role of Cilostazol Therapy in Hemodialysis Patients with Asymptomatic Peripheral Arterial Disease: A Retrospective Cohort Study

Background. Peripheral arterial disease (PAD) and its relevant complications are more common in hemodialysis (HD) patients, while the evidence regarding antiplatelet therapy in CKD patients is scarce. We retrospectively analyzed the efficacy of cilostazol on outcomes in HD patients with asymptomatic PAD (aPAD). Methods. This cohort study enrolled 217 HD patients (median follow-up time: 5.75 years). Associations between cilostazol use and the outcomes were evaluated by time-dependent Cox regression analysis. Results. During follow-up, 39.5% (47/119) patients used cilostazol for aPAD and 31.8% (69/217) patients died. Cilostazol users had significantly lower CVD and all-cause mortalities (adjusted HR [95% CI]: 0.11 [0.03, 0.51] and 0.2 [0.08, 0.52]) than nonusers. Both death risks were nonsignificantly higher in cilostazol users than in HD patients without aPAD. The unadjusted and adjusted HR [95% CI] of CVD death risk were 0.4 [0.07, 2.12] and 0.14 [0.02, 0.8] for patients with aPAD during follow-up and were 0.74 [0.16, 3.36] and 0.19 [0.04, 0.93] for those with aPAD at initial. Conclusions. In HD patients with aPAD, lower CVD and all-cause mortality rates were observed in low-dose cilostazol user. Further evidences from large-scale prospective study and randomization trial are desired to confirm the effect of cilostazol.

A modified nontransposed brachiobasilic arteriovenous fistula versus brachiocephalic arteriovenous fistula for maintenance hemodialysis access

OBJECTIVE

With the growing need for reliable and durable upper arm hemodialysis access, we sought to compare the performance of a novel modified nontransposed brachiobasilic arteriovenous fistula (mNT-BBAVF) with that of the more traditional brachiocephalic arteriovenous fistula (BCAVF).

METHODS

Briefly, to construct an mNT-BBAVF, an incision is made on the ulnar side of the elbow. The brachial artery and basilic vein are then isolated, and a side-to-side anastomosis is performed without transposition of the basilic vein. Next, the proximal basilic vein and the perforating veins within the surgical field are ligated. In this study, we retrospectively reviewed the medical records of all patients who underwent either an mNT-BBAVF or a BCAVF between January 2011 and October 2014 to compare 1-year primary unassisted patency, cumulative patency, and complications. We also examined hemodynamic parameters of vessels in each fistula type.

RESULTS

We identified a total of 84 patients: 45 had a BCAVF, and 39 had an mNT-BBAVF. The two groups were well matched for baseline characteristics. Maturation rates at 1 month were 97% for mNT-BBAVF and 96% for BCAVF. The 1-year primary unassisted patency was significantly higher in the mNT-BBAVF group than that in the BCAVF group (87% vs 67%; hazard ratio, 2.86; 95% confidence interval, 1.11-6.40; P = .03), although cumulative patency did not differ (90% vs 73%; hazard ratio, 2.80; 95% confidence interval, 0.98-6.96 ; P = .06). There were no differences in thrombosis, failure of maturation, bleeding, steal syndrome, arm swelling, aneurysm, and stenosis between the two groups during the 12-month study. Importantly, diameters and blood flow volumes of the proximal cephalic vein, distal cephalic vein, and distal basilic vein in patients who received an mNT-BBAVF increased significantly after 12 months. All three vessels met the Kidney Disease Outcomes Quality Initiative (KDOQI) criteria for fistula maturation and were available for dialysis cannulation, whereas only the proximal cephalic vein in the BCAVF group met the maturation criteria and could be used for cannulation.

CONCLUSIONS

mNT-BBAVF appeared to be an effective alternative to BCAVF for upper arm hemodialysis access.

Peripheral artery disease and chronic kidney disease: clinical synergy to improve outcomes

Persons with CKD are at a higher risk of developing peripheral artery disease (PAD) and its adverse health outcomes than individuals in the general population who have normal renal function. Classic atherosclerosis risk factors (eg, age, smoking, diabetes, hypertension, and hyperlipidemia) are common in patients with CKD, but CKD also imposes additional unique risk factors that promote arterial disease (eg, chronic inflammation, hypoalbuminemia, and a procalcific state). Current nephrology clinical practice is adversely affected by PAD diagnostic challenges, the complexities of managing 2 serious comorbid diseases, delayed vascular specialist referral, and slow PAD treatment initiation in patients with CKD. Persons with CKD are less likely to be provided recommended "optimal" PAD care. The knowledge that both limb and mortality outcomes are significantly worse in patients with CKD, especially those on dialysis, is not just a biologic fact but can serve as a care delivery call to action. Nephrologists can facilitate positive change. This article proposes that patients with PAD and CKD be strategically comanaged by care teams that encompass the skills to create and use evidence-based care pathways. This proposed collaborative multidisciplinary approach will include vascular medicine specialists, nephrologists, wound specialists, and mid-level providers. Just as clinical care quality metrics have served as the base for ESRD and acute MI quality improvement, it is time that such quality outcomes metrics be initiated for the large PAD-CKD population. This new system will identify and resolve key gaps in the current care model so that clinical outcomes improve within a cost-effective care frame for this vulnerable population.

The value of Doppler waveform analysis in predicting major lower extremity amputation among dialysis patients treated for diabetic foot ulcers

AIMS

This study examined the predictors for lower extremity amputation (LEA) in patients with diabetic foot ulcers according to kidney function and, in the case of dialysis patients, specifically evaluated the vasculature with the ankle-brachial index (ABI) and Doppler waveforms.

METHODS

Among 658 diabetic patients admitted to the Diabetic Foot Care Center, 286 had an estimated glomerular filtration rate (eGFR)≥ 60 ml/min per 1.73 m(2), 275 had an eGFR<60, and 97 patients were under maintenance dialysis. All clinical variables were analyzed. A specialist retrospectively reviewed Doppler images of 78 of the patients in dialysis to evaluate peripheral arterial disease.

RESULTS

Forty-two percent of patients with eGFR<60 presented with ABI≤0.90. For ABI values>1.40, the proportion of dialysis patients (31.3%) was greater than the proportion of patients with eGFR<60 (5.3%). Wagner wound classifications, reduced serum albumin levels, and low ABI values were the predictors for major LEA among patients in the non-dialysis groups. Nevertheless, these indicators were not predictive of the risk of amputation in diabetic patients on dialysis. The presence of poor monophasic waveforms in the dorsalis pedis artery or posterior tibial artery served as an independent predictor (odds ratio: 7.61; P=0.008) for major LEA among dialysis patients. The sensitivity and specificity were 88.0% and 59.6%, respectively.

CONCLUSIONS

Poor monophasic Doppler waveforms of below-the-knee arteries, commonly found among dialysis patients in treatment for diabetic foot ulcers, can serve as an independent predictor for major LEA.

Peripheral arterial disease in the Middle East: Underestimated predictor of worse outcome

Peripheral arterial disease (PAD) is a common manifestation of systemic atherosclerosis and is associated with significant morbidity and mortality. The prevalence of PAD in the developed world is approximately 12% among adult population, which is age-dependent and with men being affected slightly more than women. Despite the strikingly high prevalence of PAD, the disease is underdiagnosed. Surprisingly, more than 70% of primary health care providers in the US were unaware of the presence of PAD in their patients. The clinical presentation of PAD may vary from asymptomatic to intermittent claudication, atypical leg pain, rest pain, ischemic ulcers, or gangrene. Claudication is the typical symptomatic expression of PAD. However, the disease may remains asymptomatic in up to 50% of all PAD patients. PAD has also been reported as a marker of poor outcome among patients with coronary artery disease. Despite the fact that the prevalence of atherosclerotic disease is increasing in the Middle East with increasing cardiovascular risk factors (tobacco use, diabetes mellitus and the metabolic syndrome), data regarding PAD incidence in the Middle East are scarce.

Diagnosis and treatment of peripheral arterial disease in CKD patients

Peripheral arterial disease (PAD) is a cardiovascular disease risk equivalent and is a common problem in chronic kidney disease patients. Unlike in the general population, PAD in CKD occurs due to medial calcification as opposed to intimal atherosclerotic process. PAD intervention should be performed in select symptomatic patients, as described by the guidelines, and CVD risk factor modification should occur in all CKD patient, regardless of the presence of PAD. As a discipline, Interventional Nephrology has emerged out of a desire to create better outcomes for our patients and to "fix a problem." The core values of our discipline have evolved out of this fundamental desire to meet an unmet clinical need, to provide insight into a disease state specific to our patients, and to offer clinical/academic excellence in doing so. We must endeavor to follow a similar path in our approach to PAD. The purpose of this review is to educate interventional nephrologists in the diagnosis and treatment of PAD in their CKD patients.