Antiplatelet and anticoagulant drugs for prevention of restenosis/reocclusion following peripheral endovascular treatment

Anesthetic management for lower extremity vascular bypass procedures: The impact of general or regional anesthesia on clinical outcomes

PURPOSE

Postoperative complications after major surgery, especially vascular procedures, are associated with a significant increase in costs and mortality. Previous studies evaluating general anesthesia versus regional or neuraxial anesthesia for infrainguinal bypass have produced conflicting results. The main aim of the present study is to review current evidence on the application of regional or general anesthesia in patients undergoing infrainguinal bypass surgery and its potential favorable effects on postoperative outcomes.

CONTENTS

Patients undergoing vascular surgery often have multiple comorbidities, and it is important to outline both benefits and risks of regional anesthesia techniques. Neuraxial anesthesia in vascular surgery allows overall avoidance of general anesthesia and does provide short-term benefits beyond analgesia. Previous observational studies suggest that neuraxial anesthesia for lower limb revascularization may reduce morbidity and length of stay. However, evidence of long-term benefits is lacking in most procedures and further work is still warranted.

CONCLUSIONS

Neuraxial anesthesia is usually an effective anesthesia technique for infrainguinal bypass surgery. Elderly patients and those with underlying respiratory problems may display some benefit from neuraxial anesthesia. Further evaluation within institutions should be performed to identify which patients would most benefit from regional techniques. Notably, systemic antithrombotic and anticoagulation therapy is common among this population and may affect anesthetic choices.

Predicting and Analyzing Restenosis Risk after Endovascular Treatment in Lower Extremity Arterial Disease: Development and Assessment of a Predictive Nomogram

PURPOSE

This study aimed to develop and internally validate nomograms for predicting restenosis after endovascular treatment of lower extremity arterial diseases.

MATERIALS AND METHODS

A total of 181 hospitalized patients with lower extremity arterial disease diagnosed for the first time between 2018 and 2019 were retrospectively collected. Patients were randomly divided into a primary cohort (n=127) and a validation cohort (n=54) at a ratio of 7:3. The least absolute shrinkage and selection operator (LASSO) regression was used to optimize the feature selection of the prediction model. Combined with the best characteristics of LASSO regression, the prediction model was established by multivariate Cox regression analysis. The predictive models' identification, calibration, and clinical practicability were evaluated by the C index, calibration curve, and decision curve. The prognosis of patients with different grades was compared by survival analysis. Internal validation of the model used data from the validation cohort.

RESULTS

The predictive factors included in the nomogram were lesion site, use of antiplatelet drugs, application of drug coating technology, calibration, coronary heart disease, and international normalized ratio (INR). The prediction model demonstrated good calibration ability, and the C index was 0.762 (95% confidence interval: 0.691-0.823). The C index of the validation cohort was 0.864 (95% confidence interval: 0.801-0.927), which also showed good calibration ability. The decision curve shows that when the threshold probability of the prediction model is more significant than 2.5%, the patients benefit significantly from our prediction model, and the maximum net benefit rate is 30.9%. Patients were graded according to the nomogram. Survival analysis found that there was a significant difference in the postoperative primary patency rate between patients of different classifications (log-rank p<0.001) in both the primary cohort and the validation cohort.

CONCLUSION

We developed a nomogram to predict the risk of target vessel restenosis after endovascular treatment by considering information on lesion site, postoperative antiplatelet drugs, calcification, coronary heart disease, drug coating technology, and INR.

CLINICAL IMPACT

Clinicians can grade patients after endovascular procedure according to the scores of the nomograms and apply intervention measures of different intensities for people at different risk levels. During the follow-up process, an individualized follow-up plan can be further formulated according to the risk classification. Identifying and analyzing risk factors is essential for making appropriate clinical decisions to prevent restenosis.

Artificial-Intelligence-Assisted Discovery of Genetic Factors for Precision Medicine of Antiplatelet Therapy in Diabetic Peripheral Artery Disease

An increased risk of cardiovascular events was identified in patients with peripheral artery disease (PAD). Clopidogrel is one of the most widely used antiplatelet medications. However, there are heterogeneous outcomes when clopidogrel is used to prevent cardiovascular events in PAD patients. Here, we use an artificial intelligence (AI)-assisted methodology to identify genetic factors potentially involved in the clopidogrel-resistant mechanism, which is currently unclear. Several discoveries can be pinpointed. Firstly, a high proportion (>50%) of clopidogrel resistance was found among diabetic PAD patients in Taiwan. Interestingly, our result suggests that platelet function test-guided antiplatelet therapy appears to reduce the post-interventional occurrence of major adverse cerebrovascular and cardiac events in diabetic PAD patients. Secondly, AI-assisted genome-wide association study of a single-nucleotide polymorphism (SNP) database identified a SNP signature composed of 20 SNPs, which are mapped into 9 protein-coding genes (SLC37A2, IQSEC1, WASHC3, PSD3, BTBD7, GLIS3, PRDM11, LRBA1, and CNR1). Finally, analysis of the protein connectivity map revealed that LRBA, GLIS3, BTBD7, IQSEC1, and PSD3 appear to form a protein interaction network. Intriguingly, the genetic factors seem to pinpoint a pathway related to endocytosis and recycling of P2Y12 receptor, which is the drug target of clopidogrel. Our findings reveal that a combination of AI-assisted discovery of SNP signatures and clinical parameters has the potential to develop an ethnic-specific precision medicine for antiplatelet therapy in diabetic PAD patients.

Do we have a unified consensus on antithrombotic management of PAD?

Peripheral artery disease (PAD) is one of the most frequent manifestations of atherosclerosis with high rates of morbidity and mortality. Platelets and coagulation are involved in the progression of atherosclerosis and thromboembolic complications. PAD patients have increased prothrombotic potential, which includes platelet hyperaggregability and increased pro-coagulant state. Therefore, antithrombotic treatment is of utmost importance for the prevention of cardiovascular events in this group of patients. Aspirin is the basic antiplatelet drug, but with limited efficacy in PAD. In contrast to coronary artery disease, its effect on the prevention of cardiovascular events in PAD has been limited proven. Particularly in asymptomatic PAD, there is no evidence for risk reduction with aspirin. Clopidogrel and ticagrelor are more effective than aspirin. Clopidogrel is thus an effective alternative to aspirin for prevention of cardiovascular events in symptomatic PAD. In patients who are non-responders to clopidogrel, ticagrelor is indicated. Dual antiplatelet treatment (DAPT) with aspirin and ticagrelor in patients with coronary artery disease and concomitant PAD significantly decreased the rate of major adverse cardiovascular events, including adverse limb events. However, in the CHARISMA Trial, aspirin and clopidogrel were not more effective than aspirin alone and increased bleeding complications. Therefore, DAPT seems effective only in PAD accompanied by coronary artery disease. Anticoagulant treatment for symptomatic PAD with vitamin K antagonists alone or in combination with aspirin is not more effective than single antiplatelet treatment but increases the rate of major bleeding. Low dose rivaroxaban combined with aspirin in PAD patients significantly reduces cardiovascular events, including limb-threatening ischemia and limb amputations. Anticoagulation and antiplatelet treatment after percutaneous or surgical revascularization of PAD improve the patency of treated vessels. Aspirin with or without dipyridamole improved patency of infra-inguinal by-pass grafts at one year. The combination of clopidogrel with aspirin was more effective than aspirin alone in the prevention of prosthetic graft occlusions in patients undergoing below-knee by-pass-grafting. Oral vitamin K antagonists were not more effective than aspirin in the prevention of infra-inguinal by-pass occlusion. The combination of low dose rivaroxaban and aspirin was effective in preventing major adverse cardiovascular events and adverse limb events after infrainguinal endovascular or surgical revascularization in patients with intermittent claudication. However, the data on antithrombotic treatment after revascularization for limb-threatening ischemia is scanty and inconclusive. In conclusion: Antithrombotic treatment of PAD is a cornerstone for the management of these patients. Antiplatelet drugs prevent the initiation and progression of atherosclerosis and are effective also in the prevention of thromboembolic events. Simultaneous use of antiplatelet and anticoagulation drugs is accompanied by an increased risk of bleeding. However, combined treatment with aspirin and low-dose rivaroxaban is more effective than single antithrombotic treatment and safer than full-dose combined treatment.

Association of Mortality with Antiplatelet Treatment in Patients with Stent Placement or Angioplasty: A Population-Based Nested Case-Control Study

PURPOSE

Antiplatelet drugs are essential in patients with cardiovascular disease who undergo stent placement. We hypothesized that risks of mortality would differ according to adherence to antiplatelet agents, number of antiplatelet agents, and antiplatelet regimens in patients undergoing stent placement or angioplasty.

MATERIALS AND METHODS

Between 2002 and 2013, we initially enrolled 8671 subjects who underwent stent placement or angioplasty in the National Health Insurance Service-National Sample Cohort in Korea. Using the International Classification of Diseases, 10th revision, the incidence of all-cause death, including cardiovascular disease, cerebrovascular disease, and cancer, was defined. Using a nested case-control study design, controls were matched to cases at a ratio of 4:1, and a total of 5415 subjects were eligible for this study.

RESULTS

During a median follow-up period of 3.51 years, the incidence rate of all-cause death was 40 per 1000 person-years. We found that adherence to antiplatelet monotherapy significantly decreased risk of death by cerebro-cardiovascular disease, compared with discontinuation of antiplatelets [adjusted odds ratio (OR) 0.62, 95% confidence interval (CI) (0.41-0.96)]. Compared with dual antiplatelet therapy (DAPT), aspirin and clopidogrel monotherapy significantly reduced death by cerebro-cardiovascular disease [adjusted OR 0.65, 95% CI (0.44-0.95) and adjusted OR 0.58, 95% CI (0.35-0.96), respectively]. There was no significant difference of mortality between aspirin monotherapy and clopidogrel monotherapy.

CONCLUSION

Our study demonstrated that adherence to antiplatelet therapy and antiplatelet monotherapy, compared with DAPT, in patients with stent placement or angioplasty may have a beneficial effect on mortality in cerebro-cardiovascular disease.

Antithrombotic therapy for postinterventional management of peripheral arterial disease

PURPOSE

Evidence on the use of antithrombotic pharmacotherapy in patients undergoing revascularization of lower extremities for symptomatic peripheral arterial disease (PAD) is reviewed.

SUMMARY

Individuals with PAD can experience leg pain, intermittent claudication, critical limb ischemia, and acute limb ischemia. In such patients, revascularization may be indicated to improve the quality of life and to prevent amputations. Antithrombotic therapy is often intensified in the postrevascularization period to prevent restenosis of the index artery and to counteract the prothrombotic state induced by the intervention. Therapeutic modalities include dual antiplatelet therapy (DAPT), anticoagulation, a combination of antiplatelet and anticoagulation therapy, and addition of cilostazol to single antiplatelet therapy. Subgroup analyses of data from randomized clinical trials provided low-quality evidence for the use of DAPT in patients with a below-knee prosthetic bypass graft and anticoagulation for those with a venous bypass graft. Cilostazol, when added to aspirin therapy, has been shown to prevent index vessel reocclusion after an endovascular intervention in patients at low risk for thrombosis in several small randomized trials.

CONCLUSION

There is a considerable paucity of high-quality evidence on the optimal antithrombotic regimen for patients undergoing lower extremity revascularization, with no particular therapy shown to consistently improve patient outcomes. The decision to initiate intensified antithrombotic therapy should include a close examination of its risk-benefit profile. The demonstrated benefit of such treatment is restricted to the prevention of index artery reocclusion, while an increased risk of bleeding may lead to significant morbidity and mortality.

[Current concepts of anticoagulant and antiplatelet therapy in patients with vascular pathology]

The routine practice of a vascular surgeon is invariably associated with decreasing the risk of adverse cardiovascular events in patients presenting with either arterial or venous pathology. Antithrombotic therapy is one of the key approaches used to achieve this purpose. However, a wide variety of modern drugs inhibiting platelet aggregation and agents blocking the coagulation cascade, as well as their combinations makes the selection of the most appropriate treatment for a particular patient quite a difficult task. The choice should carefully be made taking into consideration the nosology, aetiology, accompanying diseases and therapy thereof, as well as the balance of the risk of ischaemic and haemorrhagic complications. Therefore, availability of modern antithrombotic drugs favourably contributing to a more personified approach to treatment is of utmost importance. Thus, for example, rivaroxaban, an anticoagulant belonging to the class of direct-acting oral factor Xa inhibitors, provides a possibility to select an optimal dosage and regimen for a particular patient with arterial or vascular pathology in practice of a cardiovascular surgeon.

Atherectomy for peripheral arterial disease

BACKGROUND

Symptomatic peripheral arterial disease (PAD) has several treatment options, including angioplasty, stenting, exercise therapy, and bypass surgery. Atherectomy is an alternative procedure, in which atheroma is cut or ground away within the artery. This is the first update of a Cochrane Review published in 2014.

OBJECTIVES

To evaluate the effectiveness of atherectomy for peripheral arterial disease compared to other established treatments.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Allied and Complementary Medicine (AMED) databases, and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 12 August 2019.

SELECTION CRITERIA

We included all randomised controlled trials that compared atherectomy with other established treatments. All participants had symptomatic PAD with either claudication or critical limb ischaemia and evidence of lower limb arterial disease.

DATA COLLECTION AND ANALYSIS

Two review authors screened studies for inclusion, extracted data, assessed risk of bias and used GRADE criteria to assess the certainty of the evidence. We resolved any disagreements through discussion. Outcomes of interest were: primary patency (at six and 12 months), all-cause mortality, fatal and non-fatal cardiovascular events, initial technical failure rates, target vessel revascularisation rates (TVR; at six and 12 months); and complications.

MAIN RESULTS

We included seven studies, with a total of 527 participants and 581 treated lesions. We found two comparisons: atherectomy versus balloon angioplasty (BA) and atherectomy versus BA with primary stenting. No studies compared atherectomy with bypass surgery. Overall, the evidence from this review was of very low certainty, due to a high risk of bias, imprecision and inconsistency. Six studies (372 participants, 427 treated lesions) compared atherectomy versus BA. We found no clear difference between atherectomy and BA for the primary outcomes: six-month primary patency rates (risk ratio (RR) 1.06, 95% confidence interval (CI) 0.94 to 1.20; 3 studies, 186 participants; very low-certainty evidence); 12-month primary patency rates (RR 1.20, 95% CI 0.78 to 1.84; 2 studies, 149 participants; very low-certainty evidence) or mortality rates (RR 0.50, 95% CI 0.10 to 2.66, 3 studies, 210 participants, very low-certainty evidence). One study reported cardiac failure and acute coronary syndrome as causes of death at 24 months but it was unclear which arm the participants belonged to, and one study reported no cardiovascular events. There was no clear difference when examining: initial technical failure rates (RR 0.48, 95% CI 0.22 to 1.08; 6 studies, 425 treated vessels; very low-certainty evidence), six-month TVR (RR 0.51, 95% CI 0.06 to 4.42; 2 studies, 136 treated vessels; very low-certainty evidence) or 12-month TVR (RR 0.59, 95% CI 0.25 to 1.42; 3 studies, 176 treated vessels; very low-certainty evidence). All six studies reported complication rates (RR 0.69, 95% CI 0.28 to 1.68; 6 studies, 387 participants; very low-certainty evidence) and embolisation events (RR 2.51, 95% CI 0.64 to 9.80; 6 studies, 387 participants; very low-certainty evidence). Atherectomy may be less likely to cause dissection (RR 0.28, 95% CI 0.14 to 0.54; 4 studies, 290 participants; very low-certainty evidence) and may be associated with a reduction in bailout stenting (RR 0.26, 95% CI 0.09 to 0.74; 4 studies, 315 treated vessels; very low-certainty evidence). Four studies reported amputation rates, with only one amputation event recorded in a BA participant. We used subgroup analysis to compare the effect of plain balloons/stents and drug-eluting balloons/stents, but did not detect any differences between the subgroups. One study (155 participants, 155 treated lesions) compared atherectomy versus BA and primary stenting, so comparison was extremely limited and subject to imprecision. This study did not report primary patency. The study reported one death (RR 0.38, 95% CI 0.04 to 3.23; 155 participants; very low-certainty evidence) and three complication events (RR 7.04, 95% CI 0.80 to 62.23; 155 participants; very low-certainty evidence) in a very small data set, making conclusions unreliable. We found no clear difference between the treatment arms in cardiovascular events (RR 0.38, 95% CI 0.04 to 3.23; 155 participants; very low-certainty evidence). This study found no initial technical failure events, and TVR rates at six and 24 months showed little difference between treatment arms (RR 2.27, 95% CI 0.95 to 5.46; 155 participants; very low-certainty evidence and RR 2.05, 95% CI 0.96 to 4.37; 155 participants; very low-certainty evidence, respectively).

AUTHORS' CONCLUSIONS

This review update shows that the evidence is very uncertain about the effect of atherectomy on patency, mortality and cardiovascular event rates compared to plain balloon angioplasty, with or without stenting. We detected no clear differences in initial technical failure rates or TVR, but there may be reduced dissection and bailout stenting after atherectomy although this is uncertain. Included studies were small, heterogenous and at high risk of bias. Larger studies powered to detect clinically meaningful, patient-centred outcomes are required.

Umbrella review and meta-analysis of antiplatelet therapy for peripheral artery disease

Background

The literature on antiplatelet therapy for peripheral artery disease has historically been summarized inconsistently, leading to conflict between international guidelines. An umbrella review and meta-analysis was performed to summarize the literature, allow assessment of competing safety risks and clinical benefits, and identify weak areas for future research.

Methods

MEDLINE, Embase, DARE, PROSPERO and Cochrane databases were searched from inception until January 2019. All meta-analyses of antiplatelet therapy in peripheral artery disease were included. Quality was assessed using AMSTAR scores, and GRADE analysis was used to quantify the strength of evidence. Data were pooled using random-effects models.

Results

Twenty-eight meta-analyses were included. Thirty-three clinical outcomes and 41 antiplatelet comparisons in 72 181 patients were analysed. High-quality evidence showed that antiplatelet monotherapy reduced non-fatal strokes (3 (95 per cent c.i. 0 to 6) fewer per 1000 patients), In symptomatic patients, it reduced cardiovascular deaths (8 (0 to 16) fewer per 1000 patients), but increased the risk of major bleeding (7 (3 to 14) more events per 1000). In asymptomatic patients, monotherapy reduced non-fatal strokes (5 (0 to 8) fewer per 1000), but had no other clinical benefit. Dual antiplatelet therapy caused more major bleeding after intervention than monotherapy (37 (8 to 102) more events per 1000), with very low-quality evidence of improved endovascular patency (risk ratio 4·00, 95 per cent c.i. 0·91 to 17·68).

Conclusion

Antiplatelet monotherapy has minimal clinical benefit for asymptomatic peripheral artery disease, and limited benefit for symptomatic disease, with a clear risk of major bleeding. There is a lack of evidence to guide antiplatelet prescribing after peripheral endovascular intervention.

A Review of Antithrombotic Treatment in Critical Limb Ischemia After Endovascular Intervention

Endovascular intervention is often used to treat critical limb ischemia (CLI). Post-intervention treatment with antiplatelet and/or anticoagulant therapy has reduced morbidity and mortality due to cardiovascular complications. The purpose of this review is to shed light on the various pharmacologic treatment protocols for treating CLI following endovascular procedures. We reviewed the literature comparing outcomes after antithrombotic treatment for patients with CLI. We characterized antithrombotic therapies into three categories: (1) mono-antiplatelet therapy (MAPT) vs. dual antiplatelet therapy (DAPT), (2) MAPT vs. antiplatelet (AP) + anticoagulant (AC) therapy, and (3) AC vs. AP + AC therapy. Relevant results and statistics were extracted to determine differences in the rates of the following outcomes: (1) re-stenosis, (2) occlusion, (3) target limb revascularization (TLR), (4) major amputation, (5) major adverse cardiac events, (6) all-cause death, and (7) bleeding. Studies suggest that DAPT reduces post-surgical restenosis, TLR, and amputation for diabetic patients, without increasing major bleeding incidences, compared to MAPT. Also, AP + AC therapy provides overall superior efficacy, with no difference in bleeding incidences, compared to antiplatelet alone. Additionally, the effects were significant for restenosis, limb salvage, survival rates, and cumulative rate of above ankle amputation or death. These results suggest that treatment with DAPT and AP + AC might provide better outcomes than MAPT following the endovascular intervention for CLI, and that the ideal treatment may be related to the condition of the individual patient. However, the studies were few and heterogenous with small patient populations. Therefore, further large controlled studies are warranted to confirm these outcomes.

Outcomes From the Multicenter Italian Registry on Primary Endovascular Treatment of Aortoiliac Occlusive Disease

Purpose: To report the results of endovascular treatment of iliac and complex aortoiliac occlusive disease (AIOD) in a multicenter Italian registry. Materials and Methods: A retrospective, multicenter, observational cohort study analyzed 713 patients (mean age 68±10 years; 539 men) with isolated iliac and complex aortoiliac lesions treated with primary stenting between January 2015 and December 2017. Indications for treatment were claudication in 406 (57%) patients and critical limb ischemia in 307 (43%). According to the TransAtlantic Inter-Society Consensus II (TASC) classification, the lesions were categorized as type A (104, 15%), type B (171, 24%), type C (170, 24%), and type D (268, 37%). Early (<30 days) endpoints included mortality, thrombosis, and major complications. Late major outcomes were primary and secondary patency and freedom from reintervention as estimated by Kaplan-Meier analysis; estimates are given with the 95% confidence intervals (CIs). Associations between baseline variables and primary patency were sought with multivariate analysis; the results are presented as the hazard ratio (HR) and 95% CI. Results: Technical success was achieved in 708 (99%) lesions; in-hospital mortality was 0.6% (n=4). The median follow-up was 11 months (range 0-42). The estimated primary patency rate was 96% (95% CI 94% to 97%) at 1 year and 94% (95% CI 91% to 96%) at 2 years. The estimated secondary patency was 99% (95% CI 97% to 99%) at 1 year and 98% (95% CI 95% to 99%) at 2 years. The estimated freedom from reintervention was 98% (95% CI 96% to 99%) at 1 year and 97% (95% CI 94% to 98.5%) at 2 years. Cox regression analysis demonstrated that the application of a covered stent was associated with an increased need for reintervention (HR 1.4, 95% CI 1.10 to 1.74, p=0.005). Chronic obstructive pulmonary disease was associated with decreased primary patency (HR 3.7, 95% CI 1.25 to 10.8, p=0.018). Conclusion: Endovascular intervention with primary stent placement for aortoiliac occlusive disease achieved satisfactory 2-year patency regardless of the complexity of the lesion. Almost all TASC lesions should be considered for primary endovascular intervention if suitable.

Antiplatelet therapy for tibial balloon angioplasty: A clinical perspective

Percutaneous transluminal tibial balloon angioplasty has an important role in the therapeutic approach of critical limb ischaemia. Despite a growing number of patients with critical limb ischaemia, there are no trials to guide the pharmacologic approach post intervention. Guidelines pertaining to the antiplatelet therapy post percutaneous transluminal tibial balloon angioplasty have not been developed. In addition, critical limb ischaemia patients have multiple comorbidities and a higher risk of bleeding. To examine the shortest duration of antiplatelet therapy post percutaneous transluminal tibial balloon angioplasty, we reviewed the preclinical data used to develop the standards for the current angioplasty technique.

Endovascular therapy versus femoropopliteal bypass surgery for medium-length TASC II B and C lesions of the superficial femoral artery: An observational propensity-matched analysis

Objectives

This study was designed to compare clinical outcomes of percutaneous transluminal angioplasty with optional stenting (PTA/s) and femoropopliteal bypass (FPB) surgery as primary invasive treatment in patients with medium-length superficial femoral artery (SFA) lesions.

Methods

We performed a single-center retrospective, observational analysis in all consecutive patients who had undergone initial invasive treatment for medium-length, TASC II B and TASC II C, SFA lesions from 2004 to 2015. Primary endpoints were primary and secondary clinical patency. Secondary endpoints were complication rates and number of amputations. Kaplan–Meier curves were used to compare patency rates in the two treatment groups. Multivariate Cox regression analysis was performed to adjust for confounding variables and propensity score matching analysis was used to balance treatment groups.

Results

A total of 362 patients with a mean observation period of 4.0 years (SD ± 2.6) were analyzed. In this group, 231 patients (64%) underwent PTA/s and 131 patients (36%) FPB surgery. There was no difference in primary clinical patency at one-, three- and five-year follow-up between the PTA/s and FPB group, with rates of 79% vs. 63%, 53% vs. 78% and 71% vs. 66%, respectively ( P = 0.46). Secondary clinical patency estimates were comparable, resulting in one-, three- and five-year secondary clinical patency rates of 88%, 76% and 67% in the PTA/s group versus 88%, 80% and 79% in the bypass group ( P = 0.40). Multivariate analysis revealed no significant differences between the PTA/s and FPB groups in terms of primary clinical patency (HR 1.4; 95% CI 0.9–2.2) and secondary clinical patency (HR 1.7; 95% CI 0.9–2.9). This was confirmed in the propensity score analysis. Hospital stay (4.8 vs. 10.3 days) and complication rate (2.6% vs. 18.3%) were significantly lower in the PTA/s group ( P = 0.00). The number of amputations was comparable ( P = 0.75).

Conclusions

The clinical success of endovascular therapy and surgery for medium-length SFA lesions is comparable. Taking into account the lower morbidity rate, shorter length of hospital stay and the less invasive character of PTA/s compared with bypass surgery, patients with medium-length SFA lesions are ideally treated by an endovascular-first approach.

Angioplasty versus stenting for infrapopliteal arterial lesions in chronic limb-threatening ischaemia

BACKGROUND

Chronic limb-threatening ischaemia (CLTI) is a manifestation of peripheral arterial disease (PAD) that includes chronic ischaemic rest pain or ischaemic skin lesions, ulcers, or gangrene for longer than two weeks. The severity of the disease depends on the extent of arterial stenosis and the availability of collateral circulation. Treatment for CLTI aims to relieve ischaemic pain, heal ischaemic ulcers, prevent limb loss, improve quality of life, and prolong survival. CLTI due to occlusive disease in the infrapopliteal arterial circulation (below-knee circulation) can be treated via an endovascular technique by a balloon opening the narrowed vessel, so called angioplasty, with or without the additional deployment of a scaffold made of metal alloy or other material, so called stenting. Endovascular interventions in the infrapopliteal vasculature may improve symptoms in patients with CLTI by re-establishing in-line blood flow to the foot. Controversy remains as to whether a balloon should be used alone to open the vessel, or whether a stent should also be deployed.

OBJECTIVES

To determine the efficacy and safety of percutaneous transluminal angioplasty (PTA) alone versus PTA with stenting of infrapopliteal arterial lesions (anterior tibial artery, posterior tibial artery, fibular artery (formerly known as peroneal artery), and common tibioperoneal trunk) for patients with chronic limb-threatening ischaemia (CLTI).

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, and AMED databases, as well as World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 25 June 2018. We applied no language restrictions.

SELECTION CRITERIA

We planned to include randomised or quasi-randomised controlled trials comparing PTA versus PTA with a stent and including patients aged 18 years or over with CLTI. We defined CLTI as Fontaine stage III (ischaemic rest pain) and IV (ischaemic ulcers or gangrene) or consistent with Rutherford category 4 (ischaemic rest pain), 5 (minor tissue loss), and 6 (major tissue loss), with stenotic (> 50% luminal loss) or occluded infrapopliteal artery, including tibiofibular trunk, anterior tibial artery, posterior tibial artery, and fibular artery. We included all types of stents irrespective of design (e.g. bare-metal, drug-eluting, bio-absorbable).

DATA COLLECTION AND ANALYSIS

Two review authors (CC-TH and GNCK) independently selected suitable trials, assessed trial quality, and extracted data. An additional third review author (MLvD) assessed trial quality and, when necessary, acted as arbiter for study selection and data extraction. Outcomes included technical success of the procedure, procedural complications, patency, major amputation, and mortality. We assessed the quality of evidence using the GRADE approach.

MAIN RESULTS

We included in the review seven trials with 542 participants. One trial randomised limbs to undergo PTA alone or PTA with stent placement, and the remaining studies randomised participants. Five trials with 476 participants show that the technical success rate was greater in the stent group than in the angioplasty group (odds ratio (OR) 3.00, 95% confidence interval (CI) 1.14 to 7.93; 476 lesions; 5 studies; I² = 23%). Meta-analysis of three eligible trials with 456 participants did not show a clear difference in short-term (within six months) patency between infrapopliteal arterial lesions treated with PTA and those treated with PTA and stenting (OR 0.88, 95% CI 0.37 to 2.11; 456 lesions; 3 studies; I² = 77%). Results also did not show clear differences between treatment groups in procedure complication rate (OR 0.87, 95% CI 0.01 to 53.60; 360 participants; 5 studies; I² = 85%), rate of major amputations at 12 months (OR 1.34, 95% CI 0.56 to 3.22; 306 participants; 4 studies; I² = 0%), and rate of mortality at 12 months (OR 0.71, 95% CI 0.43 to 1.17; 497 participants; 6 studies; I² = 0%). Heterogeneity between studies was high for the outcomes procedure complications and primary patency. The overall methodological quality of the trials included in this review was moderate due to selection and performance bias. Studies used different regimens for pretreatment and post-treatment antiplatelet/anticoagulant medication. We downgraded the certainty of the overall evidence for all outcomes by one level to moderate due to inconsistency of results across studies and large confidence intervals (small numbers of trials and participants).

AUTHORS' CONCLUSIONS

Trials show that the immediate technical success rate of restoring luminal patency is higher in the stent group but reveal no clear differences in short-term patency at six months between infrapopliteal arterial lesions treated with PTA with stenting versus those treated with PTA without stenting. We ascertained no clear differences between groups in periprocedural complications, major amputation, and mortality. However, use of different regimens for pretreatment and post-treatment antiplatelet/anticoagulant medication and the duration of its use within and between trials may have influenced the outcomes. Limited currently available data suggest that high-quality evidence is insufficient to show that PTA with stent insertion is superior to use of standard PTA alone without stenting for treatment of infrapopliteal arterial lesions. Further studies should standardise the use of antiplatelets/anticoagulants before and after the intervention to improve the comparability of the two treatments.

Antiplatelet therapy for peripheral artery disease

Atherosclerotic cardiovascular (CV) disease represents one of leading cause of mortality and morbidity in Western countries. An increased risk of CV events was identified in patients with peripheral arterial diseases (PADs), which include all arterial diseases, other than coronary arteries and the aorta. In particular, lower extremity artery disease (LEAD) and/or carotid artery disease present growing incidence in general population and a consequent increase in mortality and morbidity. Medical treatment, including antiplatelet therapy, is a cornerstone in management of these patients, even when they are treated with endovascular or surgical procedures. Despite their clinical relevance, data on optimal antiplatelet treatment in this clinical setting are lacking and often derived from clinical trials on coronary artery disease and by subgroups analysis. The purpose of this review is to examine the available data from registries, randomized trials and meta-analysis on antiplatelet treatment in patients with LEAD and carotid stenosis with the aim to provide evidence to support clinical decision making.

[Prevalence of acetylsalicylic acid (ASA) - low response in vascular surgery]

BACKGROUND

Research has revealed that a decreased antiplatelet effect (low response [LR]/high on-treatment platelet reactivity [HPR]) of acetylsalicylic acid (ASA) and clopidogrel is associated with an increased risk of thromboembolic events. There are extensive ASA low response (ALR) and clopidogrel low response (CLR) prevalence data in the literature, but there are only a few studies concerning vascular surgical patients. The aim of this study was to examine the prevalence and risk factors of ALR and CLR in vascular surgical patients.

MATERIALS AND METHODS

We examined n = 154 patients with an antiplatelet long-term therapy, who were treated due to peripheral artery occlusive disease (PAD) and/or arteria carotis interna stenosis (CVD). To detect an ALR or CLR, we examined full blood probes with impedance aggregometry (ChronoLog® Aggregometer model 590). Risk factors were examined by acquisition of concomitant disease, severity of vascular disease, laboratory test results and medication.

RESULTS

We found a prevalence of 19.3 % in the ALR group and of 21.1 % in the CLR group. Risk factors for ALR were an increased platelet and leucocyte count and co-medication with pantoprazole. We found no significant risk factors for a decreased antiplatelet effect of clopidogrel treatment.

CONCLUSION

The investigated prevalence for ALR and CLR are in the range of other studies, particularly based on cardiological patients. More investigations are needed to gain a better evaluation of the risk factors for HPR and to develop an effective antiplatelet therapy regime to prevent cardiovascular complications.

Clopidogrel plus aspirin versus aspirin alone for preventing cardiovascular events

BACKGROUND

Aspirin is the prophylactic antiplatelet drug of choice for people with cardiovascular disease. Adding a second antiplatelet drug to aspirin may produce additional benefit for people at high risk and people with established cardiovascular disease. This is an update to a previously published review from 2011.

OBJECTIVES

To review the benefit and harm of adding clopidogrel to aspirin therapy for preventing cardiovascular events in people who have coronary disease, ischaemic cerebrovascular disease, peripheral arterial disease, or were at high risk of atherothrombotic disease, but did not have a coronary stent.

SEARCH METHODS

We updated the searches of CENTRAL (2017, Issue 6), MEDLINE (Ovid, 1946 to 4 July 2017) and Embase (Ovid, 1947 to 3 July 2017) on 4 July 2017. We also searched ClinicalTrials.gov and the WHO ICTRP portal, and handsearched reference lists. We applied no language restrictions.

SELECTION CRITERIA

We included all randomised controlled trials comparing over 30 days use of aspirin plus clopidogrel with aspirin plus placebo or aspirin alone in people with coronary disease, ischaemic cerebrovascular disease, peripheral arterial disease, or at high risk of atherothrombotic disease. We excluded studies including only people with coronary drug-eluting stent (DES) or non-DES, or both.

DATA COLLECTION AND ANALYSIS

We collected data on mortality from cardiovascular causes, all-cause mortality, fatal and non-fatal myocardial infarction, fatal and non-fatal ischaemic stroke, major and minor bleeding. The overall treatment effect was estimated by the pooled risk ratio (RR) with 95% confidence interval (CI), using a fixed-effect model (Mantel-Haenszel); we used a random-effects model in cases of moderate or severe heterogeneity (I2 ≥ 30%). We assessed the quality of the evidence using the GRADE approach. We used GRADE profiler (GRADE Pro) to import data from Review Manager to create a 'Summary of findings' table.

MAIN RESULTS

The search identified 13 studies in addition to the two studies in the previous version of our systematic review. Overall, we included data from 15 trials with 33,970 people. We completed a 'Risk of bias' assessment for all studies. The risk of bias was low in four trials because they were at low risk of bias for all key domains (random sequence generation, allocation concealment, blinding, selective outcome reporting and incomplete outcome data), even if some of them were funded by the pharmaceutical industry.Analysis showed no difference in the effectiveness of aspirin plus clopidogrel in preventing cardiovascular mortality (RR 0.98, 95% CI 0.88 to 1.10; participants = 31,903; studies = 7; moderate quality evidence), and no evidence of a difference in all-cause mortality (RR 1.05, 95% CI 0.87 to 1.25; participants = 32,908; studies = 9; low quality evidence).There was a lower risk of fatal and non-fatal myocardial infarction with clopidogrel plus aspirin compared with aspirin plus placebo or aspirin alone (RR 0.78, 95% CI 0.69 to 0.90; participants = 16,175; studies = 6; moderate quality evidence). There was a reduction in the risk of fatal and non-fatal ischaemic stroke (RR 0.73, 95% CI 0.59 to 0.91; participants = 4006; studies = 5; moderate quality evidence).However, there was a higher risk of major bleeding with clopidogrel plus aspirin compared with aspirin plus placebo or aspirin alone (RR 1.44, 95% CI 1.25 to 1.64; participants = 33,300; studies = 10; moderate quality evidence) and of minor bleeding (RR 2.03, 95% CI 1.75 to 2.36; participants = 14,731; studies = 8; moderate quality evidence).Overall, we would expect 13 myocardial infarctions and 23 ischaemic strokes be prevented for every 1000 patients treated with the combination in a median follow-up period of 12 months, but 9 major bleeds and 33 minor bleeds would be caused during a median follow-up period of 10.5 and 6 months, respectively.

AUTHORS' CONCLUSIONS

The available evidence demonstrates that the use of clopidogrel plus aspirin in people at high risk of cardiovascular disease and people with established cardiovascular disease without a coronary stent is associated with a reduction in the risk of myocardial infarction and ischaemic stroke, and an increased risk of major and minor bleeding compared with aspirin alone. According to GRADE criteria, the quality of evidence was moderate for all outcomes except all-cause mortality (low quality evidence) and adverse events (very low quality evidence).

Age-related macular degeneration in a randomized controlled trial of low-dose aspirin: Rationale and study design of the ASPREE-AMD study

Purpose

Although aspirin therapy is used widely in older adults for prevention of cardiovascular disease, its impact on the incidence, progression and severity of age-related macular degeneration (AMD) is uncertain. The effect of low-dose aspirin on the course of AMD will be evaluated in this clinical trial.

Design

A sub-study of the ‘ASPirin in Reducing Events in the Elderly’ (ASPREE) trial, ASPREE-AMD is a 5-year follow-up double-blind, placebo-controlled, randomized trial of the effect of 100 mg daily aspirin on the course of AMD in 5000 subjects aged 70 years or older, with normal cognitive function and without cardiovascular disease at baseline. Non-mydriatic fundus photography will be performed at baseline, 3-year and 5-year follow-up to determine AMD status.

Primary outcome measures

The incidence and progression of AMD. Exploratory analyses will determine whether aspirin affects the risk of retinal hemorrhage in late AMD, and whether other factors, such as genotype, systemic disease, inflammatory biomarkers, influence the effect of aspirin on AMD.

Conclusion

The study findings will be of significant clinical and public interest due to a potential to identify a possible low cost therapy for preventing AMD worldwide and to determine risk/benefit balance of the aspirin usage by the AMD-affected elderly. The ASPREE-AMD study provides a unique opportunity to determine the effect of aspirin on AMD incidence and progression, by adding retinal imaging to an ongoing, large-scale primary prevention randomized clinical trial.

Antithrombotic Therapy After Peripheral Vascular Intervention

Cardioprotective medications and risk-factor modification are the hallmarks of treatment for all patients with peripheral artery disease (PAD). If symptoms are life-limiting and/or do not respond to conservative treatment, endovascular or surgical revascularization can be considered especially for patients with critical limb ischemia or acute limb ischemia. The rates of peripheral vascular intervention (PVI) have risen dramatically over the past few decades and much of this care have shifted from inpatient hospital settings to outpatient settings and office-based clinics. While PVI rates have surged and technology advancements have dramatically changed the face of PVI, the data behind optimal antithrombotic therapy following PVI is scant. Currently in the USA, most patients are treated with indefinite aspirin therapy and a variable duration of clopidogrel (or other P2Y12 inhibitor)-typically 1 month, 3 months, or indefinite therapy. More observational analyses and randomized clinical trials evaluating clinically relevant outcomes such as cardiovascular morbidity/mortality and the risk of bleeding are needed to guide the optimal role and duration of antithrombotic therapy post-PVI.

[Management of complications after revascularization due to peripheral arterial occlusive disease : Prophylaxis and consistent adequate therapy after timely diagnostics]

BACKGROUND

Complications are a threat to successful revascularization for treatment of perpheral arterial occlusive disease (PAOD) and must, therefore, be either primarily prevented or effectively treated after having occurred.

OBJECTIVES

The aim of this article is to give a survey of possible complications after revascularization for treatment of PAOD and their management.

MATERIAL AND METHODS

A systematic literature review was performed in PubMed and Medline. The analysis mainly considered recent publications with a higher level of evidence.

RESULTS

Revascularization for treatment of PAOD can basically be performed by an open surgical approach, an endovascular approach or as a combination of both methods (hybrid operation). The spectrum of possible complications varies accordingly. A differentiation can be made between bleeding, ischemic and systemic complications as well as between vascular and non-vascular complications. Optimal management of complications begins with primary prophylaxis and further includes a timely diagnosis and treatment of established complications. The best prophylaxis consists of a high quality of indications and performance of revascularization.

CONCLUSION

Optimal management of complications is essential and of utmost importance for successful revascularization to treat PAOD.

Pharmacology in peripheral arterial disease: what the interventional radiologist needs to know

Peripheral arterial disease (PAD) is a progressive disease with significant morbidity and mortality. Risk factor control, using diet and lifestyle modification, exercise, and pharmacological methods, improves symptoms and reduces associated cardiovascular events in these patients. Antiplatelet agents and anticoagulants may be used to reduce the incidence of acute events related to thrombosis. The armamentarium available for symptom relief and disease modification is discussed. Novel treatments such as therapeutic angiogenesis are in their evolutionary phase with promising preclinical data.

Atherectomy for peripheral arterial disease

BACKGROUND

Symptomatic peripheral arterial disease may be treated by a number of options including exercise therapy, angioplasty, stenting and bypass surgery. Atherectomy is an alternative technique where atheroma is excised by a rotating cutting blade.

OBJECTIVES

The objective of this review was to analyse randomised controlled trials comparing atherectomy against any established treatment for peripheral arterial disease in order to evaluate the effectiveness of atherectomy.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched November 2013) and CENTRAL (2013, Issue 10). Trials databases were searched for details of ongoing or unpublished studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing atherectomy and other established treatments were selected for inclusion. All participants had symptomatic peripheral arterial disease with either claudication or critical limb ischaemia and evidence of lower limb arterial disease.

DATA COLLECTION AND ANALYSIS

Two review authors (GA and CT) screened studies for inclusion, extracted data and assessed the quality of the trials. Any disagreements were resolved through discussion.

MAIN RESULTS

Four trials were included with a total of 220 participants (118 treated with atherectomy, 102 treated with balloon angioplasty) and 259 treated vessels (129 treated with atherectomy, 130 treated with balloon angioplasty). All studies compared atherectomy with angioplasty. No study was properly powered or assessors blinded to the procedures and there was a high risk of selection, attrition, detection and reporting biases.The estimated risk of success was similar between the treatment modalities although the confidence interval (CI) was compatible with small benefits of either treatment for the initial procedural success rate (Mantel-Haenszel risk ratio (RR) 0.92, 95% CI 0.44 to 1.91, P = 0.82), patency at six months (Mantel-Haenszel RR 0.92, 95% CI 0.51 to 1.66, P = 0.79) and patency at 12 months (Mantel-Haenszel RR 1.17, 95% CI 0.72 to 1.90, P = 0.53) following the procedure. The reduction in all-cause mortality with atherectomy was most likely due to an unexpectedly high mortality in the balloon angioplasty group in one of the two trials that reported mortality (Mantel-Haenszel RR 0.24, 95% CI 0.06 to 0.91, P = 0.04). Cardiovascular events were not reported in any study. There was a reduction in the rate of bailout stenting following atherectomy (Mantel-Haenszel RR 0.45, 95% CI 0.24 to 0.84, P = 0.01), and balloon inflation pressures were lower following atherectomy (mean difference -2.73 mmHg, 95% CI -3.48 to -1.98, P < 0.00001). Complications such as embolisation and vessel dissection were reported in two trials indicating more embolisations in the atherectomy group and more vessel dissections in the angioplasty group, but the data could not be pooled. From the limited data available, there was no clear evidence of different rates of adverse events between the atherectomy and balloon angioplasty groups for target vessel revascularisation and above-knee amputation. Quality of life and clinical and symptomatic outcomes such as walking distance or symptom relief were not reported in the studies.

AUTHORS' CONCLUSIONS

This review has identified poor quality evidence to support atherectomy as an alternative to balloon angioplasty in maintaining primary patency at any time interval. There was no evidence for superiority of atherectomy over angioplasty on any outcome, and distal embolisation was not reported in all trials of atherectomy. Properly powered trials are recommended.

[Reconstruction of the aortic bifurcation: endovascular aortic repair (EVAR) and alternatives]

CLINICAL ISSUE

Diseases of the aortic bifurcation, whether stenotic or dilating, are mostly a manifestation of arteriosclerosis. If only stenosis is present aortic bifurcation disease is equivalent to a certain form of peripheral arterial occlusive disease (PAOD) characterized by the specific anatomical location. Aneurysmal disease and PAOD of the aortic bifurcation may occur together and men older than 60 years are particularly affected. The main symptom of aortic bifurcation PAOD is bilateral claudication whereas aneurysmal disease of the aortic bifurcation is frequently asymptomatic.

STANDARD TREATMENT

Therapy of stenotic and aneurysmal disease of the aortic bifurcation depends on the degree of the disease. Simple lesions, such as isolated stenoses of the aortic bifurcation or unilateral occlusions of the common iliac artery extending to the aortic bifurcation have been treated endoluminally for many years. Current standard treatment of complex aortic bifurcation disease is open surgery with implantation of an aortobifemoral bypass graft. However, recent developments in less invasive endoluminal methods have shifted the indications more towards endoluminal therapy. This development is mirrored by the international TransAtlantic Inter-Society Consensus (TASC) II recommendations from 2007 and even more clearly by the current national S3 guidelines on PAOD (http://www.degir.de/site/leitlinien). It is stated that in complex aortic bifurcation disease, such as bilateral occlusions of the common iliac arteries (TASC C lesions) or diffuse aortobiiliac stenoses and occlusions (TASC D lesions), endoluminal therapy may be considered as an alternative to open surgery. Therapy of aneurysmal disease of the aortic bifurcation depends on the pathoanatomical conditions. Prerequisite for endoluminal therapy is a sufficient landing zone for the prostheses. If this prerequisite is fulfilled endoluminal therapy is very likely comparable to open surgery with regard to technical and clinical success. Long-term results are still lacking.

DIAGNOSTIC WORK-UP

For the decision on the type of therapy and the sizing of the prostheses, thin-slice (≤ 3 mm slice thickness) computed tomography angiography (CTA) of the abdominal aorta and the iliac arteries including multiplanar reconstruction in the sagittal and coronal plane are sufficient. The inguinal arteries have to be included in the CTA volume.

PERFORMANCE

Compared to open surgery, endoluminal therapy of stenotic and aneurysmal disease of the aortic bifurcation has the advantage of reduced invasiveness. Hence patient recovery and hospital stay may be shorter.

ACHIEVEMENTS

Therapy of stenotic and aneurysmal disease of the aortic bifurcation is changing. Standard treatment of complex aortic bifurcation disease, which is open surgery is extended by the possibilities of endoluminal methods. Due to improvements in current endoluminal systems and development of new techniques, the importance of endoluminal therapy will further increase.

PRACTICAL RECOMMENDATIONS

Good quality of the preinterventional CTA is important for planning the intervention. In order for a radiologist to offer endoluminal therapy, besides knowledge of interventional skills a close cooperation with clinical colleagues, in particular vascular surgeons is mandatory.

Cilostazol is associated with improved outcomes after peripheral endovascular interventions

OBJECTIVE

Although cilostazol is commonly used as an adjunct after peripheral vascular interventions, its efficacy remains uncertain. We assessed the effect of cilostazol on outcomes after peripheral vascular interventions using meta-analytic techniques.

METHODS

We searched MEDLINE (1946-2012), Cochrane CENTRAL (1996-2012), and trial registries for studies comparing cilostazol in combination with antiplatelet therapy to antiplatelet therapy alone after peripheral vascular interventions. Treatment effects were reported as pooled risk/hazard ratio (HR) with random-effects models.

RESULTS

Two randomized trials and four retrospective cohorts involving 1522 patients met inclusion criteria. Across studies, mean age ranged from 65 to 76 years, and the majority of patients were male (64%-83%); mean follow-up ranged from 18 to 37 months. Most interventions were in the femoropopliteal segment, and overall, 68% of patients had stents placed. Pooled estimates demonstrated that the addition of cilostazol was associated with decreased restenosis (relative risk [RR], 0.71; 95% confidence interval [CI], 0.60-0.84; P < .001), improved amputation-free survival (HR, 0.63; 95% CI, 0.47-0.85; P = .002), improved limb salvage (HR, 0.42; 95% CI, 0.27-0.66; P < .001), and improved freedom from target lesion revascularization (RR, 1.36; 95% CI, 1.14-1.61; P < .001). There was no significant reduction in mortality among those receiving cilostazol (RR, 0.73; 95% CI, 0.45-1.19; P = .21).

CONCLUSIONS

The addition of cilostazol to antiplatelet therapy after peripheral vascular interventions is associated with a reduced risk of restenosis, amputation, and target lesion revascularization in our meta-analysis of six studies. Consideration of cilostazol as a medical adjunct after peripheral vascular interventions is warranted, presuming these findings are broadly generalizable.

Incidence, predictors, and prognosis of in-stent occlusion after endovascular treatment with nitinol stents for femoropopliteal lesions

OBJECTIVE

Widespread use of self-expanding nitinol stent-based endovascular treatment (EVT) for femoropopliteal (FP) lesions has been fueled by its less-invasive nature and modest durability; however, prevalence, predictors and prognosis of in-stent occlusion are undefined and were investigated here.

METHODS

This study entailed a multicenter, retrospective analysis of a prospectively maintained database. Between January 2004 and December 2011, 2447 de novo FP lesions (mean length, 143 ± 87 mm; 52% chronic total occlusions) from 2008 patients (mean age, 73.0 ± 9.2 years; 71% male; 61% diabetics; 32% critical limb ischemia; and 24% on hemodialysis) were treated with nitinol stent-based EVT. Study outcome was in-stent occlusion: rates (1, 3, and 5 years), predictors and association with limb prognosis.

RESULTS

In-stent occlusion rate was 5.2%, 11.2%, and 16.4% at 1, 3, and 5 years, respectively (mean follow-up, 2.3 ± 1.7 years). Female sex, critical limb ischemia, and Transatlantic Inter-Society Consensus II class C/D (multivariate Cox proportional hazard ratio [HR], 1.75, 1.49, and 3.34, respectively) were independent predictors of in-stent occlusion after FP stenting, which was associated with poor limb prognosis (major amputation, HR 6.35; major adverse limb event, major adverse limb event, HR, 21.1).

CONCLUSIONS

Moderate in-stent occlusion rates were observed after nitinol stent-based EVT. Closer attention is warranted with high-risk cases because of poorer limb prognosis.