Association of diabetes and hemodialysis with ankle pressure and ankle-brachial index in Japanese patients with critical limb ischemia

Clinical implications of diverse calcification patterns in endovascular therapy for femoral-popliteal arterial occlusive disease

OBJECTIVE

The aim of this study was to investigate whether intimal arterial calcification (IAC) and medial arterial calcification (MAC) are correlated with the various clinical outcomes following endovascular therapy (EVT) for peripheral arterial disease (PAD).

METHODS

This single-center retrospective study comprised 154 consecutively hospitalized individuals with PAD who underwent EVT for de novo femoral-popliteal calcific lesions from January 2016 to July 2021. The predominant calcification patterns of IAC and MAC were assessed using a semi-quantitative computed tomography scoring system. The Kaplan-Meier method and Cox regression were conducted to evaluate the correlations between calcification patterns and medium- to long-term outcomes.

RESULTS

The distribution of calcification patterns was as follows: IAC in 111 patients (72%) and MAC in 43 patients (28%). No remarkable variation was noted between the IAC and MAC groups regarding age (P = .84) and gender (P = .23). The MAC group indicated lower rates of 4-year primary patency, assisted primary patency, secondary patency, and amputation-free survival (AFS) compared with the IAC group (24% ± 7% vs 40% ± 6%; P = .003; 30% ± 8% vs 51% ± 6%; P = .001; 51% ± 8% vs 65% ± 5%; P = .004; and 43% ± 9% vs 76% ± 5%; P < .001, respectively). There was no significant difference in the rate of freedom from clinically driven target lesion revascularization between the MAC and IAC groups (63% ± 10% vs 73% ± 5%; P = .26). Stepwise multivariable Cox regression analysis demonstrated that MAC was associated with poor patency (hazard ratio, 1.81; 95% confidence interval, 1.12-2.93; P = .016) and AFS (hazard ratio, 2.80; 95% confidence interval, 1.52-5.16; P = .001).

CONCLUSIONS

Compared with IAC, MAC is independently associated with lower medium- to long-term patency and AFS after EVT for de novo femoral-popliteal occlusive lesions.

Impact of postprocedural minimum lumen area on clinical outcome after femoropopliteal drug-eluting stent implantation

INTRODUCTION

Although favorable results of fluoropolymer-based drug-eluting stent (FP-DES) treatment for femoropopliteal lesions have been reported, it is unclear whether minimal lumen area (MLA) after FP-DES implantation affects clinical outcomes. This study aimed to reveal the association between intravascular ultrasound (IVUS)-evaluated MLA and the 1-year risk of restenosis and aneurysmal degeneration after FP-DES implantation for femoropopliteal lesions.

METHODS

A subanalysis of the CAPSICUM (Contemporary outcomes After Paclitaxel-eluting peripheral Stent implantation for symptomatic lower limb IsChemia with sUperficial feMoral or proximal popliteal lesion) study analyzed 718 limbs in 686 patients with available IVUS-evaluated MLA data. The association of MLA with the 1-year risk of restenosis and aneurysmal degeneration was analyzed using the generalized propensity score method.

RESULTS

The 1-year incidence rate of restenosis was estimated to be 8.8% (95% CI, 6.1% to 12.5%) for the upper quartile of MLA (21.1 mm2) versus 14.3% (95% CI, 10.7% to 18.7%) for the lower quartile of MLA (15.2 mm2), with an odds ratio of 0.58 (95% CI, 0.36 to 0.93; p = 0.024), whereas the 1-year incidence rate of aneurysmal degeneration was 23.8% (95% CI, 19.5% to 28.8%) for the upper quartile versus 16.8% (95% CI, 12.6% to 22.0%) for the lower quartile, with an odds ratio of 1.55 (95% CI, 1.04 to 2.32; p = 0.031).

CONCLUSION

A large MLA after FP-DES implantation for femoropopliteal lesions was associated with decreased restenosis risk but increased aneurysmal degeneration risk. These findings suggest that MLA is a valuable predictor of clinical outcomes.

Diabetes Mellitus and Lower Extremity Peripheral Artery Disease

Lower extremity peripheral artery disease, or often simply called peripheral artery disease (PAD), is a common cardiovascular disease, as coronary artery disease is. Atherosclerotic disease of the arteries of the lower extremity, or arteriosclerosis obliterans, accounts for the vast majority of PAD today. Rest pain, nonhealing ulcers, and gangrenes associated with chronic ischemia (i.e., Fontaine stage III and IV or Rutherford category 4 to 6) are referred to as chronic limb-threatening ischemia (CLTI), formally called critical limb ischemia (CLI). This narrative review focuses on atherosclerotic PAD, especially CLTI, mainly highlighting its link with diabetes mellitus (DM). This article will first overview the clinical impact of DM in patients with symptomatic PAD and that of symptomatic PAD in patients with DM, followed by the clinical features of CLTI, which will be discussed from a viewpoint of its prognosis, patient profile, onset, and seasonality. DM poses a great clinical impact on CLTI, and vice versa. Patient profile appears different between DM patients complicated with CLTI and the general population with DM. Furthermore, although CLTI is pathologically rooted in atherosclerosis as is acute coronary syndrome (ACS), CLTI has considerably different clinical features compared with ACS. CLTI has an extremely poor prognosis even after revascularization, and there is ample room for improvement in terms of its prognosis. Some measures might be needed in healthcare and clinical settings before revascularization: e.g., DM control and regular ischemia risk evaluation before CLTI onset, proper diagnosis at CLTI onset, and prompt referral to a vascular specialist after CLTI onset, although its evidence is still scanty. Piling up evidence of patients with CLTI, by patients with CLTI, and for patients with CLTI is needed.

Poor survival of dialysis patients with unhealed wounds because of critical limb ischemia: Limb salvage and survival requires wound healing

Maintenance of blood flow in the wound area is required to heal wounds of critical limb ischemia (CLI) in dialysis patients. However, many dialysis patients have both a stenotic lesion in below-knee blood vessels and a cardiovascular event as complications, and thus, it may be difficult to ensure sufficient blood flow. Therefore, many deaths occur because of problems with wound healing. The aim of this study is to identify the optimal treatment, including revascularisation and amputation, from the perspective of wound healing by analysing the survival of hemodialysis patients with CLI who had healed or unhealed wounds in a lower extremity. The subjects were 52 patients who received maintenance dialysis at our clinic, including 27 with healed CLI wounds and 25 with unhealed CLI wounds. The Kaplan-Meier method was used to compare survival between the two groups. Multivariate analysis was conducted to examine the effect of an unhealed wound on mortality. The mean follow-up period was 1.7 ± 1.1 years. In the unhealed wound group, the 1-, 2-, and 3-year survival rates were 48%, 20%, and 12%, respectively. The overall survival rate was significantly lower in the unhealed wound group compared with the healed wound group (12% vs 63%, P = .0002 by log-rank test). In multivariate analysis, unhealed CLI wounds had a significant independent association with mortality (hazard ratio 3.32; 95% confidence interval [CI]: 1.41-8.77, P = .0054). In this study, the 3-year survival rate suggested a significantly poorer prognosis of hemodialysis patients with unhealed CLI wounds compared with those with healed wounds. An unhealed wound is an independent risk factor for mortality in hemodialysis patients with CLI.

MiR-323b-5p acts as a novel diagnostic biomarker for critical limb ischemia in type 2 diabetic patients

Type 2 diabetes mellitus (T2DM) is a major contributor to peripheral artery disease (PAD), especially in cases that advance to critical limb ischemia (CLI). Accumulating evidence indicates that miRNAs play an important role in the development of PAD and T2DM. Due to the limited value of current diagnostic methods for CLI in T2DM patients, we compared the miRNA expression profiles of Chinese T2DM patients with or without CLI to find out whether distinctive miRNAs could serve as potential diagnostic biomarkers. We statistically identified 7 miRNAs (hsa-miR-200b-3p, hsa-miR-2115-3p, hsa-miR-431-5p, hsa-miR-486-5p, hsa-miR-210-3p, hsa-miR-1264, hsa-miR-323b-5p) which were up-regulated in the CLI group, whereas other 4 miRNAs (hsa-miR-5579-3p, hsa-miR-665, hsa-miR-4285, hsa-miR-500a-3p) were down-regulated. Our validation test suggested a relatively high diagnostic accuracy of serum hsa-miR-323b-5p levels for the detection of CLI in T2DM patients, with a sensitivity of 62.67% and a specificity of 80.65%. The area under the curve (AUC) for miR-323b-5p + confounding risk factors was 0.94 (95% CI: 0.884-0.994, P < 0.001), which was higher than that for miR-323b-5p. Taken together, our results indicate that circulating hsa-miR-323b-5p could be a promising serum biomarker for the diagnosis of critical limb ischemia in type 2 diabetic patients.

Risk factors for foot ulceration in adults with end-stage renal disease on dialysis: study protocol for a prospective observational cohort study

BACKGROUND

Adults with end-stage renal disease treated with dialysis experience a high burden of foot ulceration and lower extremity amputation. However, the risk factors for foot ulceration in the dialysis population are incompletely understood due to the lack of high-quality prospective evidence. This article outlines the design of a prospective observational cohort study, which aims to investigate the risk factors for foot ulceration in adults on dialysis.

METHODS/DESIGN

This study will recruit 430 participants with end-stage renal disease on dialysis from satellite and home-therapy dialysis units across multiple health organisations in Melbourne, Victoria, Australia. Data collection at baseline will include a participant interview, medical record review, completion of a health-status questionnaire and a non-invasive foot assessment. Twenty participants will also be recruited to a reliability study to evaluate the reproducibility of testing procedures. Primary outcome data includes: new foot ulcer(s). Secondary outcome data includes: number of new foot ulcers, time to onset of new foot ulcer(s), new lower extremity amputation(s), episodes of infection of the foot or lower extremity, episodes of osteomyelitis, foot-related hospitalisations, revascularisation procedure(s) of the lower extremity, new podiatry interventions, kidney transplantation, and mortality. Participants will be assessed at baseline, and at 12 months they will be evaluated for the primary and secondary outcomes. Multivariate Cox proportional hazards models will be used to assess predictors of new foot ulceration and time to event secondary outcomes. Logistic regression will be used for binary outcomes including prevalence of foot ulcerations.

DISCUSSION

This is the first multi-centre prospective observational cohort study to investigate risk factors for foot ulceration in adults with end-stage renal disease on dialysis. This study will improve on prior studies by using prospective methods, multi-centre recruitment, statistical methods to control for confounding variables, and a pre-specified sample size estimation. The findings can inform the design of future trials evaluating the effectiveness of clinical interventions, which may lead to improved patient outcomes in the dialysis setting.

Prediction of Development of Critical Limb Ischemia in Hemodialysis Patients

Hemodialysis (HD) patients with critical limb ischemia (CLI) suffer chronic inflammation and repeated infection, require intervention, and may have a protracted hospital stay. Therefore, early prediction is particularly important for management of CLI in patients with suspected peripheral artery disease. The purpose of this study is to develop a simple score for predicting the incidence of CLI in HD patients with suspected peripheral artery disease. The subjects were 139 asymptomatic patients receiving maintenance HD and with ABI <1.0. Multivariate logistic regression analysis was used to identify factors associated with development of CLI. These factors were subsequently weighted and integrated into a scoring system for the prediction of onset of CLI. Twenty-five patients had onset of CLI. Five factors selected from the multivariate model were weighted proportionally using their respective odds ratio (OR) for incidence of CLI (history of cerebral vascular disease, OR 6.42 [3 points]; diabetes, OR 3.92 [2 points]; hypoesthesia, OR 4.21 [2 points]; left ventricular ejection fraction <50%, OR 3.89 [2 points]; serum albumin <3.5 g/dL, OR 4.39 [2 points]). Three strata of risk were defined (low risk, 0 to 3 points; intermediate risk, 4 to 6 points; and high risk 7 to 11 points) with excellent prognostic accuracy for progression to CLI using the Kaplan-Meier method. Five factors were identified that increased the risk of progression to CLI in HD patients with suspected peripheral artery disease. A combination of those factors permitted establishment of three risk strata for accurate prediction of onset of CLI.