Balloon dilation and stent implantation for treatment of femoropopliteal arterial disease: meta-analysis

Peripheral arterial disease: a literature review

INTRODUCTION

Peripheral arterial disease (PAD) is a common vascular condition that affects both quality of life and life expectancy with an increased risk of cardiovascular events.

SOURCES OF DATA

A literature search was carried out of Pub-Med, MEDLINE, the Cochrane Library and Google Scholar from the establishment of these databases up to February 2012. The search was performed by using the keywords 'peripheral arterial disease' and one of the following words: 'management', 'investigations', 'risk factors', 'epidemiology', 'revascularization', 'cryoplasty', 'atherectomy' and 'gene therapy'. Studies were limited to those published in English language.

AREAS OF AGREEMENT

Aggressive risk factors modification is needed to reduce cardiovascular-related mortality in PAD patients.

AREAS OF CONTROVERSY

Choice of endovascular or surgical intervention remains controversial in an ever-evolving field.

GROWING POINTS

There is a rapid expansion of endovascular technologies aiming to improve the effectiveness of this modality.

AREAS TIMELY FOR DEVELOPING RESEARCH

The advances in the fields of gene therapy and therapeutic angiogenesis mean these are potential future treatments. Tissue engineering is a developing area and aims to produce grafts with similar patency and infection profiles to those of autologous material. Further elucidation of the pathophysiology of atherosclerosis is required to provide new targets for pharmacotherapy.

Crioplastia para tratamento da doença arterial fêmoro-poplítea

CONTEXTO: O tratamento endovascular da doença arterial obstrutiva periférica apresenta baixa morbidade e mortalidade, no entanto, a perviedade dos stents a médio e longo prazo ainda é controversa. A crioplastia foi desenvolvida para reduzir os grandes desafios da angioplastia: dissecção, retração e reestenose. OBJETIVO: Avaliar os resultados clínicos e a perviedade a médio prazo em pacientes submetidos à técnica de crioplastia da doença arterial do território femoro-poplíteo. MÉTODOS: Pacientes com indicação de revascularização de membro inferior por técnica endovascular do território femoro-poplíteo, segundo as classificações clínicas de Fontaine e Rutherford e classificações anatômicas do TASC II, foram submetidos à crioplastia com cateter balão PolarCath®. No seguimento, foram avaliadas as manifestações clínicas e perviedade anatômica pelo duplex scan. RESULTADOS: Dez pacientes foram submetidos à angioplastia do território femoro-poplíteo utilizando a técnica de crioplastia. Nove pacientes apresentavam quadro clínico de claudicação limitante do membro inferior e um paciente apresentava úlcera isquêmica, três pacientes apresentavam lesão classe B pelo TASC II e sete pacientes, classe A. Sucesso técnico angiográfico inicial foi obtido em todos os casos, sendo que um caso necessitou do implante de stent devido à dissecção. Seguimento foi realizado em 9 pacientes, por período médio de 31,6 meses (28-35), com perviedade primária de 77,7% e perviedade secundária de 100%. Todos os pacientes apresentam-se assintomáticos no final do seguimento (Fontaine I). CONCLUSÕES: A crioplastia do território femoro-poplíteo é um método seguro, de baixa morbidade, com resultados a curto e médio prazo comparáveis à angioplastia convencional e com potencial de reduzir as taxas de dissecção e retração durante o procedimento, e redução do grau de reestenose a médio e longo prazo.

WITHDRAWN: Rationale and Design of a Randomised Controlled Trial Comparing Stent-Protected Angioplasty with Bypass Surgery for Intermittent Claudication: The ABC Study

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Current approach to the diagnosis and treatment of femoral-popliteal arterial disease. A systematic review

Peripheral arterial disease (PAD) is a common manifestation of atherosclerosis affecting 5 million adults in the United States, with an age-adjusted prevalence of 4% to 15% and increasing up to 30% with age and the presence of cardiovascular risk factors. In this article we focus on lower extremity PAD and specifically on the superficial femoral and proximal popliteal artery (SFPA), which are the most common anatomic locations of lower extremity atherosclerosis. We summarize current evidence and perform a systematic review on the diagnostic evaluation as well as the medical, endovascular and surgical management of SFPA disease.

[Evolution of stents for the treatment of femoral artery lesions]

Endovascular treatment and stent implantation in the superficial femoral artery have been proposed for over 20 years. However, the first experiments with stainless stents were relatively disappointing. The first improvement consisted in the introduction of nitinol self-expanding stents. This technology allowed an initial improvement of clinical performances, but the first generation of nitinol stents demonstrated a relatively high rate of fractures. Better knowledge of the femoral artery biomechanics and advances in technology allowed to propose a second generation of nitinol stents with improved flexibility, which decreased the rates of fracture. In-stent restenosis related to neointimal hyperplasia has also led to the development of new concepts to improve patency rates after stenting of the femoral artery: drug-eluting stents (coated-stents), biodegradable stents, and covered stents. These technologies will help to treat more complex lesions of the femoral artery in the future, with comparable results to those obtained with femoropopliteal bypasses, but we are still waiting for results of ongoing studies.

Drug-eluting stents and balloons in peripheral arterial disease: evidence so far

Restenosis by myointimal hyperplasia after peripheral arterial angioplasty or stenting is a major problem limiting its long-term efficiency and patency, and may lead to recurrent symptoms. Drug-eluting devices which inhibit the proliferation of neo-intimal growth of vascular smooth muscle cells may prevent restenosis. The aim of this article is to examine the evidence in published literature on the use of drug-eluting devices in the treatment of peripheral arterial diseases. A systematic literature review was undertaken of all published literature on this subject using Medline and cross-referenced. All published relevant articles on the use of drug-eluting stents and balloons in peripheral arterial disease were used. Cochrane Central Register of Controlled Trials and electronic databases were also searched for on-going studies. Published results from randomised studies such as the SIROCCO I and II Trials and the THUNDER study, together with single cohort studies, are now available. There are on-going studies comparing drug-eluting and non-drug-eluting devices. Evidence from the published literature suggests that drug-eluting stents and balloons are safe and effective in preventing restenosis after peripheral angioplasty. However, drug-eluting devices are more expensive and many are limited to single-use only. It is anticipated that results from all the on-going studies may allow a meta-analysis to show whether these preliminary data can translate into a clinically applicable cost-effective strategy in combating restenosis after peripheral angioplasty or stenting.

The use of the CUSUM chart method for surveillance of learning effects and quality of care in endovascular procedures

INTRODUCTION

Quality of care and learning effect surveillance are two mandatory responsibilities within a changing therapeutical paradigm. We aimed to evaluate the feasibility and value of CUSUM chart method in assessing performance in consecutive endovascular procedures done by vascular surgeons of a single department on aorto-iliac, femoropopliteal and renal artery occlusive disease.

MATERIAL AND METHOD

Data were collected in 405 consecutive patients, scheduled for endovascular intervention of aorto-iliac (n = 131, 32.3%), femoropopliteal (n = 142, 35%) and renal artery (n = 132, 32.7%) occlusive disease during a 6-year period. Quality indicators included inability to cross the lesion, peri- and post-procedural complications and significant residual stenosis or occlusion at 1 month. CUSUM curves were generated for each territory globally and according to each quality indicator. The relevance of curve upward inflections was evaluated with Fisher's Exact Test.

RESULTS

Failure to cross the lesion occurred in 6.9% (aorto-iliac), 10.6% (femoropopliteal) and 2.3% (renal) of patients. One-hundredth twenty aorto-iliac, 127 femoropopliteal and 132 renal angioplasties were finally performed. Peri- and post-procedural complications appeared in 14.5% (aorto-iliac), 9.2% (femoropopliteal) and 2.3% (renal), while significant residual stenosis or occlusion was seen in 0.8%, 4.9% and 2.3% of patients, respectively. Aorto-iliac CUSUM curve showed two upward inflections at the beginning and the end of the period, both associated with peri- and post-procedural complications (p = 0.002 and p = 0.0013) and the latter also with failure to cross the lesion (p = 0.009). Femoro-popliteal CUSUM curve moved progressively upward during all the period, initially related to peri- and post-procedural complications (p = 0.038) and later to failure to cross the lesion (p = 0.004). Renal CUSUM curve didn't show any upward inflection during the analysed period.

CONCLUSION

CUSUM curves are an excellent tool for measuring learning effect and quality of care within a changing paradigm, such it is the case of endovascular interventions. Curve upward inflections can be further interpreted according to the type of "failure" thus helping to evaluate their underlying causes.

Cryoplasty versus conventional balloon angioplasty of the femoropopliteal artery in diabetic patients: long-term results from a prospective randomized single-center controlled trial

The purpose of this study was to investigate the immediate and long-term results of cryoplasty versus conventional balloon angioplasty in the femoropopliteal artery of diabetic patients. Fifty diabetic patients (41 men, mean age 68 years) were randomized to cryoplasty (group CRYO; 24 patients with 31 lesions) or conventional balloon angioplasty (group COBA; 26 patients with 34 lesions) of the femoropopliteal artery. Technical success was defined as <30% residual stenosis without any adjunctive stenting. Primary end points included technical success, primary patency, binary in-lesion restenosis (>50%), and freedom from target lesion recanalization. Cox proportional hazards regression analysis was performed to adjust for confounding factors of heterogeneity. In total, 61.3% (19 of 31) in group CRYO and 52.9% (18 of 34) in group COBA were de novo lesions. More than 70% of the lesions were Transatlantic Inter-Society Consensus (TASC) B and C in both groups, and 41.4% of the patients in group CRYO and 38.7% in group COBA suffered from critical limb ischemia. Immediate technical success rate was 58.0% in group CRYO versus 64.0% in group COBA (p = 0.29). According to 3-year Kaplan-Meier estimates, there were no significant differences with regard to patient survival (86.8% in group CRYO vs. 87.0% in group COBA, p = 0.54) and limb salvage (95.8 vs. 92.1% in groups CRYO and COBA, respectively, p = 0.60). There was a nonsignificant trend of increased binary restenosis in group CRYO (hazard ratio [HR] 1.3; 95% CI 0.6-2.6, p = 0.45). Primary patency was significantly lower in group CRYO compared with group COBA (HR 2.2; 95% CI 1.1-4.3, p = 0.02). Significantly more repeat intervention events because of recurrent symptoms were required in group CRYO (HR 2.5; 95% CI 1.2-5.3, p = 0.01). Cryoplasty was associated with lower primary patency and more clinically driven repeat procedures after long-term follow-up compared with conventional balloon angioplasty.

Nitinol stent implantation versus balloon angioplasty for lesions in the superficial femoral artery and proximal popliteal artery: twelve-month results from the RESILIENT randomized trial

BACKGROUND

Controversy still exists regarding the best endovascular treatment strategy for patients with symptomatic disease of the superficial femoral artery. There are conflicting data regarding the benefits of superficial femoral artery stenting and the role of primary stenting compared with balloon angioplasty with provisional stent implantation.

METHODS AND RESULTS

A total of 206 patients from 24 centers in the United States and Europe with obstructive lesions of the superficial femoral artery and proximal popliteal artery and intermittent claudication were randomized to implantation of nitinol stents or percutaneous transluminal angioplasty. The mean total lesion length was 71 mm for the stent group and 64 mm for the angioplasty group. Acute lesion success (<30%residual stenosis) was superior for the stent group compared with the angioplasty group (95.8% versus 83.9%; P<0.01). Twenty-nine (40.3%) patients in the angioplasty group underwent bailout stenting because of a suboptimal angiographic result or flow-limiting dissection. Bailout stenting was treated as a target lesion revascularization and loss of primary patency in the final analysis. At 12 months, freedom from target lesion revascularization was 87.3% for the stent group compared with 45.1% for the angioplasty group (P<0.0001). Duplex ultrasound-derived primary patency at 12 months was better for the stent group (81.3% versus 36.7%; P<0.0001). Through 12 months, fractures occurred in 3.1% of stents implanted. No stent fractures resulted in loss of patency or target lesion revascularization.

CONCLUSIONS

In this multicenter trial, primary implantation of a self-expanding nitinol stent for moderate-length lesions in the superficial femoral artery and proximal popliteal artery was associated with better acute angiographic results and improved patency compared with balloon angioplasty alone.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00673985.

The role of endothelial cells and their progenitors in intimal hyperplasia

Intimal hyperplasia leading to restenosis is the major process that limits the success of cardiovascular intervention. The emergence of vascular progenitor cells and, in particular, endothelial progenitor cells has led to great interest in their potential therapeutic value in preventing intimal hyperplasia. We review the mechanism of intimal hyperplasia and highlight the important attenuating role played by a functional endothelium. The role of endothelial progenitor cells in maintaining endothelial function is reviewed and we describe how reduced progenitor cell number and function and reduced endothelial function lead to an increased risk of intimal hyperplasia. We review other potential sources of endothelial cells, including monocytes, mesenchymal stem cells and tissue resident stem cells. Endothelial progenitor cells have been used in clinical trials to reduce the risk of restenosis with varied success. Progenitor cells have huge therapeutic potential to prevent intimal hyperplasia but a more detailed understanding of vascular progenitor cell biology is necessary before further clinical trials are commenced.

[S3 guidelines for diagnostics and treatment of peripheral arterial occlusive disease]

This report summarizes the most important aspects of the new German S3 guidelines for the diagnostics and treatment of peripheral arterial occlusive disease (PAOD) from March 2009. The guidelines include definitions and epidemiology of peripheral arterial occlusive disease, diagnostic methods including clinical and technical procedures as well as imaging methods, treatment by non-invasive, interventional and surgical methods and patient care during follow-up. In key messages recommendations are given which are graded corresponding to the scientific evidence concluded from the literature.

Endovascular treatment of peripheral vascular disease

Peripheral arterial disease (PAD) affects about 27 million people in North America and Europe, accounting for up to 413,000 hospitalizations per year with 88,000 hospitalizations involving the lower extremities and 28,000 involving embolectomy or thrombectomy of lower limb arteries. Many patients are asymptomatic and, among symptomatic patients, atypical symptoms are more common than classic claudication. Peripheral arterial disease also correlates strongly with risk of major cardiovascular events, and patients with PAD have a high prevalence of coexistent coronary and cerebrovascular disease. Because the prevalence of PAD increases progressively with age, PAD is a growing clinical problem due to the increasingly aged population in the United States and other developed countries. Until recently, vascular surgical procedures were the only alternative to medical therapy in such patients. Today, endovascular practice, percutaneous transluminal angioplasty with or without stenting, is used far more frequently for all types of lower extremity occlusive lesions, reflecting the continuing advances in imaging techniques, angioplasty equipment, and endovascular expertise. The role of endovascular intervention in the treatment of limb-threatening ischemia is also expanding, and its promise of limb salvage and symptom relief with reduced morbidity and mortality makes percutaneous transluminal angioplasty/stenting an attractive alternative to surgery and, as most endovascular interventions are performed on an outpatient basis, hospital costs are cut considerably. In this monograph we discuss current endovascular intervention for treatment of occlusive PAD, aneurysmal arterial disease, and venous occlusive disease.

Endovascular management of the popliteal artery: comparison of atherectomy and angioplasty

PURPOSE

Symptomatic atherosclerotic disease of the popliteal artery presents challenges for endovascular therapy. We evaluated the technical success, complications, and midterm outcomes of atherectomy and angioplasty involving the popliteal segment.

METHODS

We conducted a retrospective review of outcomes of popliteal artery intervention using atherectomy or angioplasty performed between 2003 and 2008.

RESULTS

A total of 56 patients (36% women, age 72.8 +/- 12.2 years, 77% critical limb ischemia) underwent popliteal atherectomy (n = 18) or angioplasty (n = 38). These patients had similar clinical characteristics, TransAtlantic Intersociety Consensus (TASC)/ TASC II classification, mean lesion length, and runoff scores. We observed a trend toward higher rates of technical success defined as <30% residual stenosis after atherectomy compared to angioplasty (94% vs 71%, P = .08). While angioplasty was associated with a higher frequency of arterial dissection (23% vs 0%, P = .003), atherectomy was associated with a higher rate of thromboembolic events (22% vs 0%, P = 0.01). Adjunctive stenting was used more frequently following angioplasty compared to atherectomy (45% vs 6%, P = .005). Thrombolysis was used to treat embolization in 4 patients in the atherectomy group. The improvement in the ankle-brachial index (ABI) was similar between the 2 treatment groups. Primary patency of the popliteal artery at 3, 6, and 12 months was 94%, 88%, and 75% in the atherectomy group and 89%, 82%, and 73% in the angioplasty group (P = not significant [NS]). There were no significant differences in limb salvage and freedom from reintervention at 1 year between the atherectomy and angioplasty groups.

CONCLUSIONS

Our experience with popliteal artery endovascular therapy indicates a distinct pattern of procedural complications with atherectomy compared to angioplasty but similar midterm patency, limb salvage, and freedom from intervention.

Lipoprotein(a) and other serum lipid subfractions influencing primary patency after infrainguinal percutaneous transluminal angioplasty

PURPOSE

To evaluate the influence of serum lipid subfraction concentrations on arterial patency after percutaneous transluminal angioplasty (PTA) in patients with infrainguinal peripheral artery occlusive disease (PAOD).

METHODS

From January 2007 to June 2008, a prospective study was conducted involving 39 patients (29 men; mean age 68.6+/-10.0 years) with infrainguinal PAOD in 41 limbs who had preprocedural lipid assessment and underwent successful PTA (<30% residual stenosis). Patient demographics, Fontaine clinical stage classification, Texas University Classification of ulcers, coexisting medical conditions, endovascular procedures, and lipid profiles were collected in a database. Follow-up included clinical and duplex ultrasound evaluation at discharge and at 1, 3, 6, and 12 months. To analyze any correlation between various lipid subfractions and the loss of primary patency (Cox proportional hazards modeling), the patients were dichotomized into high and low groups according to these thresholds: LDL-C >100 mg/dL, HDL-C <40 mg/dL, Lp(a) >30 mg/dL, and an Apo(B)/Apo(A) ratio >0.8 mg/dL.

RESULTS

Mean follow-up was 7.5 months (range 3-12). After 1, 3, and 6 months, the primary patency rates by Kaplan-Meier analysis were 94.9%, 73.7%, and 64.1%, respectively. Restenosis at 6 months was significantly related to female gender (HR 95.9, 95% CI 6.8 to 1352.5, p = 0.001), HDL-C <40 mg/dL (HR 86.9, 95% CI 6.4 to 1183.1, p = 0.001), LDL-C >100 mg/dL (HR 9.6, 95% CI 1.6 to 57.4, p = 0.013), and Lp(a) >30 mg/dL (HR 6.1, 95% CI 1.4 to 26.3, p = 0.016).

CONCLUSION

Our results suggest that Lp(a), LDL-C, and HDL-C are independent risk factors for restenosis after infrainguinal PTA.

[Peripheral arterial disease. Diagnosis and therapy according to current guidelines]

Guidelines conduce to establish consistent standards of therapy and contribute to the orientation and safeguard of the attending physician. Peripheral arterial disease (PAD) may be classified according to its stage as intermittent claudication, chronic critical limb ischemia or acute limb ischemia. Since these diseases are common and life-threatening, current guidelines are of major interest for the attending physician, not least because of forensic reasons. This overview describes the current principles of diagnosis and therapy as well as recent developments in peripheral endovascular intervention. Current national and international guidelines, particularly the Transatlantic Intersociety Consensus (TASC), were taken into account.

Cost-effectiveness of new cardiac and vascular rehabilitation strategies for patients with coronary artery disease

Objective

Peripheral arterial disease (PAD) often hinders the cardiac rehabilitation program. The aim of this study was evaluating the relative cost-effectiveness of new rehabilitation strategies which include the diagnosis and treatment of PAD in patients with coronary artery disease (CAD) undergoing cardiac rehabilitation.

Data Sources

Best-available evidence was retrieved from literature and combined with primary data from 231 patients.

Methods

We developed a Markov decision model to compare the following treatment strategies: 1. cardiac rehabilitation only; 2. ankle-brachial index (ABI) if cardiac rehabilitation fails followed by diagnostic work-up and revascularization for PAD if needed; 3. ABI prior to cardiac rehabilitation followed by diagnostic work-up and revascularization for PAD if needed. Quality-adjusted-life years (QALYs), life-time costs (US $), incremental cost-effectiveness ratios (ICER), and gain in net health benefits (NHB) in QALY equivalents were calculated. A threshold willingness-to-pay of $75 000 was used.

Results

ABI if cardiac rehabilitation fails was the most favorable strategy with an ICER of $44 251 per QALY gained and an incremental NHB compared to cardiac rehabilitation only of 0.03 QALYs (95% CI: −0.17, 0.29) at a threshold willingness-to-pay of $75 000/QALY. After sensitivity analysis, a combined cardiac and vascular rehabilitation program increased the success rate and would dominate the other two strategies with total lifetime costs of $30 246 a quality-adjusted life expectancy of 3.84 years, and an incremental NHB of 0.06 QALYs (95%CI:−0.24, 0.46) compared to current practice. The results were robust for other different input parameters.

Conclusion

ABI measurement if cardiac rehabilitation fails followed by a diagnostic work-up and revascularization for PAD if needed are potentially cost-effective compared to cardiac rehabilitation only.

Routine stent implantation vs. percutaneous transluminal angioplasty in femoropopliteal artery disease: a meta-analysis of randomized controlled trials

AIMS

We performed a meta-analysis of randomized controlled trials comparing routine stenting (ST) with percutaneous transluminal angioplasty (PTA) for symptomatic superficial femoral-popliteal artery (SFPA) disease.

METHODS AND RESULTS

Ten trials were pooled randomizing patients to ST (n = 724 limbs) or PTA with provisional stenting (n = 718 limbs) with a follow-up period of 9-24 months. The mean lesion length was similar in the two groups (45.8 mm in the ST group and 43.3 mm in the PTA group). We calculated the summary risk ratios (RRs) for immediate technical failure, restenosis, and target vessel revascularization (TVR) using random-effects models. The immediate technical failure was higher in the PTA group than in the ST group [17.1 vs. 5.9%, respectively, RR = 0.28, 95% confidence interval (CI) = 0.15-0.54, P < 0.001], with 10.3% of the PTA patients undergoing stenting because of suboptimal result. There was a trend for lower restenosis in the ST group (37.6% in ST vs. 45.3% in PTA, RR = 0.85, 95% CI = 0.69-1.06, P = 0.146), but no difference in the need for TVR (20% in ST vs. 20.2% in PTA, RR = 0.98, 95% CI = 0.78-1.23, P = 0.89). In an analysis restricted to nitinol stents, there was a trend towards reduction in TVR (RR = 0.79, 95% CI = 0.59-1.06, P = 0.12).

CONCLUSION

Despite the higher immediate success, routine stenting was not associated with a significant reduction in the rate of restenosis or TVR. Our data do not support use of routine stenting as the primary endovascular treatment for short SFPA lesions.

[The vascular surgeon's role in interdisciplinary treatment of diabetic foot syndrome]

There are more than 6 million diabetes patients in Germany. Due to long-term neuropathic and angiopathic sequelae, the number of patients with "diabetic foot syndrome" has increased dramatically in recent years. Diabetic foot ulcers have become one of the most common pathologies in interdisciplinary wound care centers. Because of its complex pathogenesis, diabetic foot syndrome needs a multidisciplinary therapeutic approach. More than 150,000 diabetics per year develop foot ulcers that often heal slowly and progress into chronic wounds. Despite all efforts at prevention, early diagnosis, and adequate therapy, more than 20,000 diabetics suffer major limb amputation in Germany every year. Applying stringent standards of care in interdisciplinary wound care centers, the amputation rate in patients with diabetic foot syndrome can be reduced to less than 50%. This article describes the complexity of diabetic foot syndrome with respect to pathogenesis, diagnostics, and therapy from a vascular surgeon's point of view. The importance of an interdisciplinary approach is emphasized.

[Critical limb ischemia]

Critical limb ischemia can be divided into acute and chronic forms. All patients suspected of the acute form should be evaluated immediately, as urgent revascularization is usually necessary. Chronic critical limb ischemia is the most complicated type of peripheral artery disease (PAD). Typical for it are pain at rest and necrosis or gangrene. The most important known risk factors are nicotine, hypertension, diabetes, and hyperlipoproteinemia. Patients suffering from PAD run a significantly higher risk of cardiovascular or cerebrovascular events and therefore should be on permanent antithrombotic therapy as secondary prophylaxis. Besides clinical examination and determination of the ankle/brachial index, complementary imaging is mandatory. Here angiography is the gold standard. For therapy surgical and other interventional procedures are available. The decision on individual therapy follows an interdisciplinary approach based on an international consensus (TASC classification).

Endovascular therapy for critical limb ischemia

Abstract

Chronic critical limb ischemia (CLI) occurs when arterial perfusion is reduced below a threshold level that results in rest pain and/or tissue breakdown in the lower extremities. Importantly, it is associated with high cardiovascular morbidity and mortality. Without prompt revascularization, CLI may result in loss of a limb (i.e. amputation) and/or life. The goal of endovascular therapy is the re-establishment of pulsatile, straight-line flow to the distal extremity. Percutaneous transluminal angioplasty (PTA) has been shown to be effective and safe in the setting of CLI, with limb salvage rates that compare favorably with surgical procedures. Stents are indicated for failed PTA, while adjunctive therapies such as lasers, thermal angioplasty and atherectomy devices lack data demonstrating improved efficacy compared with conventional lower extremity interventions. In addition to successful revascularization, the institution of lifestyle changes, atherosclerotic risk factor modification, and pharmacologic therapies are indicated to reduce cardiovascular morbidity and mortality.

Current status of heroic limb salvage for critical limb ischemia

The treatment of chronic lower extremity peripheral arterial disease is in a state of flux. During the past decade, vascular surgeons have assumed the responsibility for the endovascular care of patients needing vascular intervention. Once surgeons began performing these procedures, a change in attitude toward angioplasty resulted in an "endovascular explosion" and an overall reassessment of the traditional approaches to critical limb ischemia. Our current method of assessing outcomes is also in a state of flux. The original measure of procedural success, reconstruction patency, has been found to be a poor predictor of both patient palliation and functional success. A shift toward determining more accurate, patient-oriented outcome measures is ongoing. Until then, evidence would suggest that there are patients with such severe medical comorbidities, which include impaired ambulatory ability at presentation, that the benefits of revascularization seem to be insignificant. As our patient population ages and our healthcare system continues to fail financially, economic rationing motivated by lack of evidence-based data to the contrary may dictate that these patients are best served by primary limb amputation.

Randomized, multicenter study comparing expanded polytetrafluoroethylene-covered endoprosthesis placement with percutaneous transluminal angioplasty in the treatment of superficial femoral artery occlusive disease

PURPOSE

To compare the safety and effectiveness of the Viabahn endoprosthesis with that of percutaneous transluminal angioplasty (PTA) alone in the treatment of symptomatic peripheral arterial disease (PAD) affecting the superficial femoral artery (SFA).

MATERIALS AND METHODS

From 1998 to 1999, patients with symptomatic SFA PAD were enrolled in a prospective, multicenter randomized study and underwent either PTA alone (n = 100) or PTA followed by stent-graft placement (expanded polytetrafluoroethylene/nitinol self-expanding stent-graft) (n = 97) for stenoses or occlusions of the SFA that were 13 cm long or shorter. At baseline, there were no significant differences between the PTA and stent-graft treatment groups, including chronic limb ischemia status and treated lesion length.

RESULTS

The stent-graft group had a significantly higher technical success rate (95% vs 66%, P < .0001) and 1-year primary vessel patency rate at duplex ultrasonography (65% vs 40%, P = .0003). A patency benefit was seen for lesions at least 3 cm long. At 12 months, chronic limb ischemia status was 15% further improved for the stent-graft group (P = .003). There were no significant differences between treatment groups with regard to the occurrence of early or late major adverse events.

CONCLUSIONS

In this multicenter study, the patency, technical success, and clinical status results obtained with stent-grafts were superior to those obtained with PTA alone.

Cryoplasty therapy for limb salvage in patients with critical limb ischemia

PURPOSE

To report the 6-month outcomes from a prospective multicenter study investigating the use of cryoplasty (cold balloon angioplasty) to treat below-knee occlusive disease in patients with critical limb ischemia (CLI).

METHODS

Between August 2004 and October 2005, 108 patients (77 men; mean age 73+/-12 years, range 41-101) with CLI involving 111 limbs were enrolled in a prospective multicenter trial (Below-the-Knee Chill Study), which was conducted at 16 institutions. The primary study endpoints were acute technical success, defined as the ability to achieve < or =50% residual stenosis and continuous inline flow to the foot, and absence of major (above or below-knee) amputation of the target limb 180 days post procedure.

RESULTS

Acute technical success was achieved in 108 (97.3%) of the 111 limbs treated, with only 1 (0.9%) clinically significant dissection (> or =type C) and 2 residual stenoses >50%. During the 180-day follow-up, 15 (13.9%) of the initial 108 patients either withdrew or were lost to follow-up. Five (4.6%) deaths occurred, leaving 88 (81.5%) patients with 91 (82.0%) treated limbs available for 180-day assessment. The rate of freedom from major amputation at 180 days was 93.4%. Amputation-free survival was 89.3% at 180 days (5 deaths, 6 major amputations). Stratifying data by diabetics (n=71) versus non-diabetics (n=34), the 180-day death and amputation rates were 4.9% and 10.0%, respectively, for diabetics versus 6.7% and 0.0%, respectively, for non-diabetics.

CONCLUSION

Cryoplasty therapy is a safe and effective method of treating infrapopliteal disease, providing excellent acute outcomes and a high rate of limb salvage in patients with CLI. Study outcomes support the use of cryoplasty therapy as a primary treatment option for patients with CLI secondary to below- knee disease.

Infrainguinal occlusive disease: endovascular intervention is the first line therapy

The preferred treatment of infrainguinal occlusive disease at many centers has undergone a paradigm shift from open bypass to endovascular intervention as the first-line therapeutic modality. Our own experience supports a percutaneous first approach. Though skeptics initially cited lower primary patency rates for angioplasty when compared with bypass, more recent studies have shown favorable secondary patencies nearly challenging that of bypass. The need for repeat endovascular intervention to achieve a higher secondary patency is not a major deterring factor because most procedures are associated with a short hospital stay and a relatively low rate of complication. The risk is low and this complex group of patients can tolerate minimally invasive reinterventions well. The longevity of this patient population is generally short, and consequently less durable outcomes may be acceptable. Patients do require close follow-up with early treatment of restenosis. However, there appears to be a decreased cost of intervention when compared with surgery. Furthermore, the functional outcomes and quality of life appear more optimal with angioplasty. The concern that angioplasty may preclude future surgical intervention by damaging the distal bypass target has not borne true. It is unusual for a percutaneous therapy to eliminate the possibility of a bypass should the endovascular approach not be successful. Finally, advances in techniques and devices may herald improved outcomes because percutaneous therapy in the periphery is still in the early stages of its maturation. Thus, endovascular intervention has become an established, as well as a developed method for treating peripheral arterial occlusive disease and should be considered the first-line therapeutic modality for patients with.lower extremity vascular disease.

Endovascular therapies for peripheral arterial disease: an evidence-based review

Peripheral arterial disease is one manifestation of systemic atherosclerosis. The prevalence of peripheral arterial disease increases with the age of the population. It is important to remember the significant association of coincident coronary artery disease, which is the major cause of mortality in these patients. Remarkable technological advances in the past decade, along with patient preference, have shifted revascularization strategies from traditional open surgical approaches toward lower-morbidity percutaneous endovascular treatments. The availability of stents, more than any other advance, has fueled the growth of catheter-based procedures by improving the safety, durability, and predictability of percutaneous revascularization.

Balloon angioplasty compared with stenting for treatment of femoropopliteal occlusive disease: a meta-analysis

BACKGROUND

The goal of this study was to review the currently available literature and to compare the short and long-term results of primary stenting and angioplasty of femoropopliteal occlusive disease by performing a meta-analysis review.

METHODS

A systematic review of the literature that was published between September 2000 and January 2007 was performed. All studies that reported data on the long-term results after balloon dilatation or stent implantation were included if at least one-year primary patency or restenosis rate was presented; the study follow-up was at least 1 year and the number of subjects at the start of study was at least 20 patients. Three investigators independently extracted the data. The Pooled survival curves were then constructed for graft patency according to a random-effects protocol for meta-analysis.

RESULTS

Twenty-four articles were initially identified but only seven were selected and included in this meta-analysis: seven were RCTs publications and one was a retrospective study comparing the outcome of angioplasty and stenting of the femoropopliteal segment. In our meta-analysis, there were a total of 934 patients with 452 patients who underwent balloon angioplasty (273 patients were male) and 482 patients who underwent stenting (297 patients were male). Primary patency at 1-year and postoperative ABI post intervention was used to evaluate the pooled odds ratio (OR) of all studies. The pooled OR of all studies estimate for the 12-month patency rates was 0.989 (95% confidence interval [CI], 0.623 to 1.570, P = .962) showing no difference in outcome between the two groups (SE 0.269% to 1.025%). The pooled OR estimate for the postoperative ABI was 0.869 (95% CI, 0.557 to 1.357, P = .561) showing a slight advantage in favor of the angioplasty group but the P value was not statistically significant (SE 0.282% to 1.326%). The 1-year primary patency rates following balloon angioplasty ranged from 45% to 84.2% and at 2 years it varied from 25% to 77.2%. In the stent implantation group, the 1-year primary patency rates varied from 63% to 90%, and 2-year primary patency ranged from 46% to 87%. Heterogeneity was seen among studies, and publication bias could not be excluded.

CONCLUSIONS

The results of our meta-analysis suggest that stent placement in the femoropopliteal occlusive disease does not increase the patency rate when compared with angioplasty alone at 1 year. This conclusion should be viewed in the light of study-design considerations and all limitations in this meta-analysis that may have an impact of the outcome of stenting and angioplasty after a 1-year follow-up.