Nitinol stenting improves primary patency of the superficial femoral artery after percutaneous transluminal angioplasty in hemodialysis patients: A propensity-matched analysis

Predictive Modeling for One-Year Lower Extremity Endovascular Revascularization Failure in Black Persons

INTRODUCTION

Black persons bear a disproportionate burden of peripheral artery disease (PAD) and experience higher rates of endovascular revascularization failure (ERF) when compared with non-Hispanic White persons. We aimed to identify predictors of ERF in Black persons using predictive modeling.

METHODS

This retrospective study included all persons identifying as Black who underwent an initial endovascular revascularization procedure for PAD between 2011 and 2018 at a midwestern tertiary care center. Three predictive models were developed using (1) logistic regression, (2) penalized logistic regression (least absolute shrinkage and selection operator [LASSO]), and (3) random forest (RF). Predictive performance was evaluated under repeated cross-validation.

RESULTS

Of the 163 individuals included in the study, 113 (63.1%) experienced ERF at 1 y. Those with ERF had significant differences in symptom status (P < 0.001), lesion location (P < 0.001), diabetes status (P = 0.037), and annual procedural volume of the attending surgeon (P < 0.001). Logistic regression and LASSO models identified tissue loss, smoking, femoro-popliteal lesion location, and diabetes control as risk factors for ERF. The RF model identified annual procedural volume, age, PAD symptoms, number of comorbidities, and lesion location as most predictive variables. LASSO and RF models were more sensitive than logistic regression but less specific, although all three methods had an overall accuracy of ≥75%.

CONCLUSIONS

Black persons undergoing endovascular revascularization for PAD are at high risk of ERF, necessitating need for targeted intervention. Predictive models may be clinically useful for identifying high-risk patients, although individual predictors of ERF varied by model. Further exploration into these models may improve limb salvage for this population.

[Interventional Treatments for Femoropopliteal Arterial Disease and Recent Updates]

Peripheral arterial occlusive disease (PAOD) of the femoropopliteal artery is commonly caused by atherosclerosis. It can present with varying clinical symptoms depending on the degree of disease, ranging from intermittent claudication to critical limb ischemia and tissue loss. Therefore, appropriate and timely treatment is required to improve symptoms and salvage the affected limbs. Interventional approaches for femoropopliteal arterial disease commonly include percutaneous transluminal angioplasty, atherectomy, and stent placement. Over the years, endovascular recanalization has been widely performed for treating PAOD due to continuous developments in its techniques and availability of dedicated devices with the inherent advantage of being minimal invasive. In this review, we introduce various types of endovascular treatment methods, discuss the results of clinical research from existing literature, and illustrate the treatment procedures using representative images.

Long-term clinical outcomes after self-expandable bare nitinol stent implantation for femoropopliteal occlusive disease in hemodialysis patients

OBJECTIVES

To compare the long-term clinical outcomes after self-expandable bare nitinol stent (BNS) implantation between hemodialysis (HD) and non-HD patients with femoropopliteal (FP) disease.

BACKGROUND

Although a BNS has been commonly used in patients with FP disease, the long-term efficacy of BNSs in HD patients remains unknown.

METHODS

In total, 427 HD patients treated with a BNS for FP disease were enrolled, along with 157 non-HD patients as a control group. Over the following 5 years, the incidence of target lesion revascularization (TLR), major amputation and mortality was investigated. We also performed propensity-score matching analysis.

RESULTS

The 5-year TLR rate (45.2 vs. 32.5%, p = .013) and mortality rate (39.3 vs. 14.0%, p = .0002) were significantly higher in the HD group than in the non-HD group. The major amputation rate was comparable between the groups (7.2% in the HD group vs. 2.8% in the non-HD group, p = .16). In the propensity-score-matched cohort, the TLR rate, and mortality rate were remained higher in the HD group than in the non-HD group (48.9 vs. 34.1%, hazard ratio [HR] 2.11, 95% confidence interval [CI] 1.30-3.49, p = .0024, and 47.9 vs. 12.0%, HR 3.38, 95% CI 1.86-6.56, p < .0001, respectively). The adjusted amputation rate was consistently similar between the groups (1.7% in the HD group vs. 2.7% in the non-HD group, HR 0.90, 95% CI 0.26-2.99, p = .86).

CONCLUSIONS

The TLR rate and mortality at 5 years post BNS implantation for FP disease were significantly higher in HD patients than in non-HD patients, though the limb salvage rate was similar.

Recent Update on Peripheral Arterial Endovascular Therapy for Peripheral Arterial Occlusive Disease

Endovascular treatment is effective for symptomatic peripheral arterial disease (PAD). Following recent device improvements, favorable long-term outcomes have been achieved in iliac arteries as well as small arteries such as the femoral and popliteal arteries. This paper outlines the history and recent advances in endovascular treatment of peripheral vascular diseases as well as the characteristics and usage of devices. The history and the advances in endovascular treatment of peripheral vascular disease have been parallel, with the development of devices such as catheters and stents. Accordingly, endovascular treatment is now recommended in guidelines as the first-line for PAD.

Impact of Chronic Renal Failure on Safety and Effectiveness of Paclitaxel-Eluting Stents for Femoropopliteal Artery Disease: Subgroup Analysis from Zilver PTX Post-Market Surveillance Study in Japan

Purpose

Favorable long-term outcomes of the Zilver PTX drug-eluting stent (DES) in femoropopliteal lesions have been demonstrated. Chronic renal failure (CRF) has been shown to be a risk factor for restenosis and decreased limb salvage. The results of the DES in patients with CRF have not previously been reported. This study compares the results with the DES in patients with CRF and those without CRF.

Methods

This retrospective analysis from the Zilver PTX Japan Post-Market Surveillance Study included 321 patients with CRF and 584 patients without CRF. Outcomes included freedom from target lesion revascularization (TLR) and patency.

Results

Of the patients included in this subgroup analysis, 2-year data were available for 209 patients in the CRF group and 453 patients in the non-CRF group. The two groups were similar in terms of lesion length and the frequency of in-stent restenosis. Critical limb ischemia, severe calcification, and diabetes were more common in patients with CRF, whereas total occlusion was more common in patients without CRF. Freedom from TLR rates were 81.4 versus 84.9% (p = 0.24), and patency rates were 70.7 versus 70.3% (p = 0.95) in patients with and without CRF at 2 years, respectively.

Conclusion

This is the first comparative study of the DES in femoropopliteal artery lesions in patients with and without CRF. These results indicate that the DES placed in femoropopliteal artery lesions of CRF patients is safe and effective with similar patency and TLR rates to patients without CRF.

Level of Evidence

Level 3, Post-Market Surveillance Study.

Early Post-Registry Experience With Drug-Eluting Stents in the Superficial Femoral Artery

OBJECTIVE

Restenosis remains the primary failure mode after stent placement in the superficial femoral artery (SFA). Drug-eluting technology aims to reduce intimal hyperplasia and subsequent stent failure, improving durability for endovascular management of SFA occlusive disease. We present our early experience with the Cook Zilver PTX stent.

METHODS

We retrospectively reviewed a prospectively collected database of patients undergoing placement of the Cook Zilver PTX stent for SFA or popliteal disease since its availability to our institution in October 2013. Patients treated with additional non-PTX stents were excluded. Patient demographics, comorbidities, concomitant procedures, TASC classification, procedural details, and follow-up were reviewed.

RESULTS

Thirty-one limbs in 30 patients were treated with Zilver PTX stents, 5 limbs were excluded for concomitant use of non-PTX stents, leaving 26 limbs in 26 patients for analysis. Indications for intervention were claudication in 17 (65.4%), rest pain in 1 (3.8%), and tissue loss in 8 (30.8%). A median of 2 PTX stents per limb was used to treat a mean length of 14.2 ± 11 cm with technical success of 100%. Concomitant inflow (N = 4) or atherectomy (N = 2) interventions were performed in 23%. Sixty-nine percent of lesions were TASC C (N = 7) or D (N = 11) and 42% were total occlusions. Over a mean 20-week follow-up, 2 occlusions were noted (mean 27 weeks), one was treated with surgical bypass and the other with endovascular salvage. Limb salvage in the series was 92.3% with 2 patients requiring major amputations for infected, non-healing wounds, despite patent stents.

CONCLUSION

On mean 20-week follow-up, we have seen 92.3% primary patency and 96.2% secondary patency. A larger number of patients and longer follow-up will be required to determine the true real-world efficacy of this drug-eluting device, but early experience is encouraging and warrants continued trial.

Comparison of long-term patency after endovascular therapy for superficial femoral artery occlusive disease between patients with and without hemodialysis

OBJECTIVE

To compare long-term patency after endovascular therapy (EVT) for superficial femoral artery (SFA) occlusive disease between patients with hemodialysis (HD; HD+) and those without HD (HD-).

BACKGROUND

Long-term patency after EVT for SFA occlusive disease in HD+ remains unknown.

METHODS

EVT to SFA was successfully performed in 382 consecutive patients during 2004-2011. Cox proportional hazard model estimated the hazard ratio (HR) for the loss of primary patency (PP), secondary patency (SP), and amputation-free survival (AFS) in HD+. Binominal logistic regression analysis calculated the propensity score (PS) for covariates with a P value of <0.2 for HD as a dependent variable. HRs were adjusted for PS in multivariate analysis using the Cox proportional hazard model.

RESULTS

PP and SP in HD+ and HD- were 47.9 and 79.4% and 68.4 and 92.5%, respectively, 4 years after EVT. There were no procedure-related amputations or in-hospital deaths. Adjusted HRs for the loss of PP, SP, and AFS were as follows: loss of PP, adjusted HR 2.010, 95% CI 1.157-3.492, P = 0.013; loss of SP, adjusted HR 2.927, 95% CI 1.236-6.933, P = 0.015; and loss of AFS, adjusted HR 1.665, 95% CI 0.994-2.791, P = 0.053.

CONCLUSIONS

Although HD+ had more than double the risks for loss of PP and SP than HD-, EVT to SFA in HD+ was found to be safe with an acceptable PP and SP. © 2015 Wiley Periodicals, Inc.

Factors Affecting the Results of Superficial Femoral Artery Stenting

INTRODUCTION

The aim of this study was to assess the durability of superficial femoral artery (SFA) stents and factors that affect stent patency.

METHODS

A retrospective assessment of 214 SFA stent procedures between 2003 and 2012 was conducted from a prospectively compiled database. Patency rates and patient outcomes were compiled from case notes and computerized records. Stent patency was confirmed by either duplex scan or clinical examination (palpable distal pulse). Survival and patency were compared across a range of factors using Kaplan-Meier plots and log-rank tests. Factors found to be significant were further assessed by Cox regression models.

RESULTS

Data were analyzed for 214 limbs in 205 patients. Inclusion criteria included those patients who received an SFA stent for treatment of claudication or critical limb ischemia (CLI) with follow-up data. This gave a study group of 151 limbs divided into 76 claudicant and 75 patients with CLI (male-female ratio = 103:48, mean age 71 years, standard deviation 11.7). Seventy-one percent of procedures were elective and 29% were emergency procedures; 53% of procedures were carried out on a day case basis. Median follow-up was 11 months (range 1 day-89 months). Patency was significantly worse for patients with CLI (P = .009), with a 1- and 3-year patency of 63% and 34% compared to 79% and 60% in patients with claudication. Significant factors associated with patency included oral therapy controlled diabetes (P = .003), lesions located in either the mid-SFA (P = .029) or the mid-popliteal (P = .013), and periprocedural complications (P = .005). There was no significant difference in patency rates between insulin-dependent and nondiabetic patients (hazard ratio: 1.0, 95% confidence interval: 0.4-5.6, P = .983). The overall amputation rate for the total study group was 5%. Patients with 1- and 3-year survival were 98% and 96% in the claudication group and 74% and 51%, respectively, in the CLI group.

CONCLUSION

SFA stents have superior outcomes in claudicants. Patency is related to severity of disease, diabetes, and location of disease.

S.M.A.R.T. self-expanding nitinol stent for the treatment of atherosclerotic lesions in the superficial femoral artery (STROLL): 1-year outcomes

PURPOSE

To assess safety and efficacy of the S.M.A.R.T. Vascular Stent System (Cordis Corp, Fremont, California) in obstructive superficial femoral artery (SFA) disease.

MATERIALS AND METHODS

The single-arm, multicenter STROLL study (S.M.A.R.T. Nitinol Self-Expanding Stent in the Treatment of Obstructive Superficial Femoral Artery Disease) included 250 patients (250 lesions in SFA or proximal popliteal artery). The efficacy endpoint was primary patency defined by freedom from binary restenosis (peak systolic velocity ratio > 2.5) as derived by duplex ultrasound plus clinically driven target lesion revascularization (TLR) at 12 months.

RESULTS

Mean age of patients was 67.7 years ± 10.3; 47.2% of patients had diabetes; distribution of Rutherford/Becker classes 2, 3, and 4 was 45.8%, 51.4%, and 2.8%. Mean lesion length and reference vessel diameter were 77.3 mm ± 35.3 and 4.9 mm ± 0.7, respectively (23.6% cases with total occlusions). The 30-day freedom from major adverse events (death, index limb amputation, clinically driven TLR) was 100%. The 1-year primary patency was 81.7% by Kaplan-Meier estimate. The presence of diabetes or total occlusion had no effect on primary patency. Ankle-brachial index was 0.4-0.8 in 84.6% of patients at baseline and improved to > 0.8 in 81.0% of patients at 12 months. The proportion of patients in Rutherford/Becker class 3-4 was reduced from 54.2% at baseline to 8.0% at 12 months. Four patients (2.0%) experienced single-stent strut fracture (type I) at 1 year, without associated loss of stent patency.

CONCLUSIONS

The S.M.A.R.T. Vascular Stent System proved to be safe and effective for endovascular treatment of obstructive SFA and proximal popliteal artery disease, based on 1-year vessel patency and associated hemodynamic and clinical improvements.

Application of rotational atherectomy for a calcified superficial femoral artery lesion

A 78-year-old man on dialysis with a history of femoro-popliteal bypass grafting of his right superficial femoral artery was presented with a recurrence of intermittent claudication. Angiography revealed new heavily calcified stenosis located distal to the anastomosis of the graft. A guide wire was crossed the lesion, however, a balloon catheter could not pass. Rotational atherectomy with Rotablator enabled the balloon to cross the lesion with full dilatation. Due to residual stenosis and dissection, a stent was implanted. Final angiogram showed no residual stenosis with TIMI 3 flow. The patient remained free of symptoms during the 1-year follow-up.

Impact of endovascular therapy on oxidative stress in patients with peripheral artery disease

BACKGROUND

Atherosclerosis is believed to be caused by oxidative stress. Endovascular therapy (EVT) is effective for claudication of patients with peripheral artery disease (PAD). However, its effect on oxidative stress in PAD patients is unknown. Here, the impact of EVT on oxidative stress in PAD patients is investigated.

METHODS AND RESULTS

Twenty-five PAD patients (Rutherford stage II or III) who underwent EVT were enrolled. The levels of diacron-reactive oxygen metabolite (d-ROM; an oxidative stress marker), ankle-brachial index (ABI), and maximum walking distance at baseline and at 3 months after EVT were measured. As compared with baseline values, the maximum walking distance and ABI improved significantly after EVT (109.9±104.2 vs. 313.7±271.8m, P<0.0001; 0.61±0.15 vs. 0.91±0.13m, P<0.0001, respectively). The improved exercise capacity and arterial flow induced a significant decrease in d-ROM levels (from 472.8±64.8 to 390.2±46.7U.CARR; P<0.0001). The decrease in d-ROM levels after EVT was more prominent in PAD patients with a high baseline d-ROM level. The increased ABI (r=0.524, P=0.0007) and maximum walking distance (r=-0.416, P=0.039) after EVT were significantly correlated with the decreased d-ROM levels.

CONCLUSIONS

The improved exercise capacity and peripheral blood flow induced by EVT decreases oxidative stress in PAD patients.

Prognostic values of C-reactive protein levels on clinical outcome after endovascular therapy in hemodialysis patients with peripheral artery disease

PURPOSE

Endovascular therapy (EVT) has been widely performed for peripheral artery disease. However, the high restenosis rate after EVT remains a major problem in patients on hemodialysis. Recent studies suggest that C-reactive protein (CRP) reflects vascular wall inflammation and can predict adverse events. We evaluated the possible prognostic values of CRP on outcomes in hemodialysis patients undergoing EVT.

METHODS

A total of 234 hemodialysis patients undergoing EVT for peripheral artery disease were enrolled and followed-up for up to 5 years. They were divided into tertiles according to serum CRP levels (lowest tertile, < 1.4 mg/L; middle tertile, 1.4-6.0 mg/L; highest tertile, ≥ 6.0 mg/L). We analyzed the incidence of any reintervention or above-ankle amputation of the limb index (RAO) and any-cause death.

RESULTS

Kaplan-Meier analysis showed that the event-free rate from the composite end point of RAO and any-cause death for 5 years was 60.2% in the lowest tertile, 50.0% in the middle tertile, and 25.1% in the highest tertile (P < .0001). The survival rate from any-cause death for 5 years was 81.5% in the lowest tertile, 65.2% in the middle tertile, and 59.3% in the highest tertile (P = .0078). Even after adjusting for other risk factors at baseline, preprocedural CRP levels were a significant predictive factor for RAO and any-cause death after EVT in a multivariable Cox analysis.

CONCLUSIONS

Elevated preprocedural serum CRP levels were associated with RAO and any-cause death after EVT in hemodialysis patients with peripheral artery disease.