Editor's Choice – Dual Antiplatelet Therapy Improves Outcome in Diabetic Patients Undergoing Endovascular Femoropopliteal Stenting for Critical Limb Ischaemia

Antithrombotic therapy following revascularization for chronic limb-threatening ischaemia: a European survey from the ESC Working Group on Aorta and Peripheral Vascular Diseases

Aims

Chronic limb-threatening ischaemia (CLTI) entails dismal outcomes and is an absolute indication to lower extremity revascularization (LER) whenever possible. Antithrombotic therapy is here crucial, but available evidence on best strategies (choice of drugs, combinations, duration) is scarce. We conducted a European internet-based survey on physicians’ use of antithrombotic therapy after revascularization for CLTI, under the aegis of the ESC Working Group on Aorta and Peripheral Vascular Disease in collaboration with other European scientific societies involved in CLTI management and agreeing to send the survey to their affiliates.

Methods and results

225 respondents completed the questionnaire. Antithrombotic therapy following surgical/endovascular LER varies widely across countries and specialties, with dedicated protocols reported only by a minority (36%) of respondents. Dual antiplatelet therapy with aspirin and clopidogrel is the preferred choice for surgical (37%) and endovascular (79%) LER. Dual pathway inhibition (DPI) with aspirin and low-dose rivaroxaban is prescribed by 16% of respondents and is tightly related to the availability of reimbursement (OR 6.88; 95% CI 2.60–18.25) and to the choice of clinicians rather than of physicians performing revascularization (OR 2.69; 95% CI 1.10–6.58). A ≥ 6 months-duration of an intense (two-drug) postprocedural antithrombotic regimen is more common among surgeons than among medical specialists (OR 2.08; 95% CI 1.10–3.94). Bleeding risk assessment is not standardised and likely underestimated.

Conclusion

Current antithrombotic therapy of CLTI patients undergoing LER remains largely discretional, and prescription of DPI is related to reimbursement policies. An individualised assessment of thrombotic and bleeding risks is largely missing.

Mono or Dual Antiplatelet Therapy for Treating Patients with Peripheral Artery Disease after Lower Extremity Revascularization: A Systematic Review and Meta-Analysis

The efficacy of dual antiplatelet therapy (DAPT) for patients with peripheral artery disease (PAD) after lower-limb intervention remains controversial. Currently, the prescription of DAPT after an intervention is not fully recommended in guidelines due to limited evidence. This study compares and analyzes the prognosis for symptomatic PAD patients receiving DAPT versus monotherapy after lower-limb revascularization. Up to November 2021, PubMed/MEDLINE, Embase, and Cochrane databases were searched to identify studies reporting the efficacy, duration, and bleeding complications when either DAPT or monotherapy were used to treat PAD patients after revascularization. Three randomized controlled trials and seven nonrandomized controlled trials were included in our study. In total, 74,651 patients made up these ten studies. DAPT in PAD patients after intervention was associated with lower rates of all-cause mortality (HR = 0.86; 95% CI, 0.79−0.94; p < 0.01), major adverse limb events (HR = 0.60; 95% CI, 0.47−0.78; p < 0.01), and major amputation (HR = 0.78; 95% CI, 0.64−0.96) when follow-up was for more than 1-year. DAPT was not associated with major bleeding events when compared with monotherapy (OR = 1.22; 95% CI, 0.69−2.18; p = 0.50) but was associated with a higher rate of minor bleeding as a complication (OR = 2.54; 95% CI, 1.59−4.08; p < 0.01). More prospective randomized studies are needed to provide further solid evidence regarding the important issue of prescribing DAPT.

Management of chronic peripheral artery disease patients with indication for endovascular revascularization

With an increasing global burden of patients with chronic peripheral artery disease (PAD) the safe and effective provision of lower limb revascularisation is a growing medical need. Endovascular procedures for the treatment of PAD have become a crucial cornerstone of modern vascular medicine, and the first line revascularisation approach if technically feasible and taking patient choice into consideration. With the increasing age of patients with PAD and the increasing number of comorbidities open vascular surgery is also often not feasible. We outline a framework of key messages, endorsed by the board of the European Society of Vascular Medicine for pre-, peri- and post procedural management of patients requiring endovascular arterial procedures of the lower limbs. These key messages emphasize the important and increasing role of interventional vascular physicians.

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.

Comprehensive Assessment of Current Management Strategies for Patients With Diabetes and Chronic Limb-Threatening Ischemia

Chronic limb-threatening ischemia (CLTI) is the most severe form of peripheral artery disease. It is estimated that 60% of all nontraumatic lower-extremity amputations performed annually in the United States are in patients with diabetes and CLTI. The consequences of this condition are extraordinary, with substantial patient morbidity and mortality and high socioeconomic costs. Strategies that optimize the success of arterial revascularization in this unique patient population can have a substantial public health impact and improve patient outcomes. This article provides an up-to-date comprehensive assessment of management strategies for patients afflicted by both diabetes and CLTI.

Impact of Dual Antiplatelet Therapy after Lower Extremity Revascularization for Chronic Limb Threatening Ischemia (CLTI)

BACKGROUND

The optimal antiplatelet regimen after lower extremity revascularization in patients with chronic limb threatening ischemia (CLTI) is unknown since current recommendations are based on extrapolation of data from trials in coronary artery disease and stroke.

METHODS

We identified all patients undergoing an elective lower extremity revascularization for CLTI in the Vascular Quality Initiative registry discharged on a mono antiplatelet agent (MAPT) or dual antiplatelet therapy (DAPT).

RESULTS

From 2003 to 2018, 50,890 patients underwent revascularization procedures for CLTI, and were discharged on MAPT or DAPT. Of these, 33,781 patients underwent endovascular therapy (EVT) and 17,109 patients underwent open surgery (OS) procedures. The rate of major amputation at 30 days in the target limb in the EVT group was 0.3% and 0.4% in the OS group (P=.22). On Kaplan Meier analyses, patients on MAPT at discharge had a higher risk 1-year major amputation compared to DAPT after EVT but not after OS procedures. Patients on MAPT had lower overall survival and amputation free survival (AFS) at 30 days and 1 year compared to DAPT after both EVT and OS. At 1 year, the MAPT group was at higher risk for target lesion re-intervention after EVT compared to the DAPT group (15.9% vs. 13%, P= .0012). There was no significant difference in thrombosis at 1 year between MAPT and DAPT groups either after EVT (3.9% vs. 3.7%; P = .3048) or OS (3.1% vs. 3.2%; P= .2893). On cox regression analysis, DAPT was associated with improved survival but not major amputation after both EVT and OS.

CONCLUSIONS

In CLTI patients, DAPT at the time of discharge has a positive impact on AFS and overall survival after both EVT and OS as well as target lesion re-intervention after EVT. DAPT was not associated with a positive impact on major amputation after either EVT or OS.

Short-Term Clinical Outcomes of Single Versus Dual Antiplatelet Therapy after Infrainguinal Endovascular Treatment for Peripheral Arterial Disease

After infrainguinal endovascular treatment for peripheral arterial disease (PAD), it is uncertain whether single antiplatelet therapy (SAPT) or dual antiplatelet therapy (DAPT) should be preferred. This study investigated major adverse limb events (MALE) and major adverse cardiovascular events (MACE) between patients receiving SAPT and DAPT. Patient data from three centers in the Netherlands were retrospectively collected and analyzed. All patients treated for PAD by endovascular revascularization of the superficial femoral, popliteal, or below-the-knee (BTK) arteries and who were prescribed acetylsalicylic acid or clopidogrel, were included. End points were 1-, 3-, and 12-month MALE and MACE, and bleeding complications. In total, 237 patients (258 limbs treated) were included, with 149 patients receiving SAPT (63%) and 88 DAPT (37%). No significant differences were found after univariate and multivariate analyses between SAPT and DAPT on 1-, 3-, and 12-month MALE and MACE, or bleeding outcomes. Subgroup analyses of patients with BTK treatment showed a significantly lower 12-month MALE rate when treated with DAPT (hazard ratio 0.33; 95% confidence interval 0.12-0.95; p = 0.04). In conclusion, although patient numbers were small, no differences were found between SAPT and DAPT regarding MALE, MACE, or bleeding complications. DAPT should, however, be considered over SAPT for the subgroup of patients with below-the-knee endovascular treatment.

Antiplatelet and anticoagulation therapy after revascularization for lower extremity artery disease: a national survey and literature overview

BACKGROUND

Antiplatelet therapy (APT) after interventions for lower extremity artery disease (LEAD) is recommended. However, (inter)national guidelines vary on type and duration of APT. This report aimed to present the results of a survey on antithrombotic prescribing patterns after lower limb interventions in the Netherlands and an overview of the available literature on this topic.

METHODS

Vascular surgeons from the Dutch Society for Vascular Surgery and interventional radiologists from the Dutch Society for Interventional Radiology received an online survey on the type and duration of antithrombotic medication after lower limb interventions.

RESULTS

Surveys were completed by 139 of 285 vascular surgeons (49%) and 24 of 288 (8%) interventional radiologists. Clopidogrel was the most prescribed drug after iliac percutaneous transluminal angioplasty (PTA) (77%), femoral PTA (77%), femoral PTA with drug-coated balloon (66%), and femoropopliteal (80%) and femorocrural (51%) prosthetic bypasses. Dual APT (DAPT), consisting of aspirin and clopidogrel, was most often prescribed after femoral PTA with stenting (56%) and crural PTAs (55% without stent, 73% with stent). Vitamin K antagonists were most often prescribed after femoropopliteal (83%) and femorocrural (80%) venous bypasses. Aspirin monotherapy prescription varied from 1% to 8% after interventions. Many interventional radiologists responded that they only advise in medication prescription but do not prescribe themselves.

CONCLUSIONS

Prescription of antiplatelet and anticoagulation therapy in LEAD patients after femoral and crural interventions varies widely among Dutch vascular surgeons, mostly between clopidogrel and DAPT. The duration of DAPT is also highly variable. These results reflect low-level evidence and discrepancy in current guideline recommendations.

Single versus dual antiplatelet therapy following peripheral arterial endovascular intervention for chronic limb threatening ischaemia: Retrospective cohort study

Objectives

Antiplatelet therapy following peripheral arterial endovascular intervention lacks high quality evidence to guide practice. The aim of this study was to assess the effect of three months of dual antiplatelet therapy on amputation-free survival following peripheral arterial endovascular intervention in patients with chronic limb threatening ischemia.

Methods

A retrospective review of symptomatic patients undergoing primary peripheral arterial endovascular intervention over a seven-year period was performed. The primary outcome measure was amputation-free survival. A sample size calculation based on previous cohort studies suggested that 629 limbs would be required to show a difference between single and dual therapy. Kaplan-Meier estimates and multivariate logistic regression analysis of recorded baseline characteristics was performed to determine predictors of amputation-free survival. Dual antiplatelet therapy was routinely given for 3 months.

Results

754 limbs were treated with primary angioplasty and/or stenting over a 7-year period, 508 of these for chronic limb threatening ischemia. There was no difference in unadjusted amputation-free survival between patients with chronic limb threatening ischaemia taking single vs. dual antiplatelet therapy (69% vs. 74% respectively Log rank Chi² = 0.1, p = .72). After adjusting for confounders, at 1 year there was also no significant difference in amputation-free survival between patients taking single vs. dual antiplatelet therapy [OR 0.8, 95% CI 0.5–1.2, p = .3]. There was no difference in rates of major bleeding between single and dual antiplatelet therapy.

Conclusions

There was no clear evidence of reduced amputation-free survival in patients with chronic limb threatening ischemia undergoing peripheral arterial endovascular intervention being treated with dual antiplatelet therapy for 3 months. This is at odds with other retrospective case series and highlights the limitations in basing clinical practice on such data. There is a need for an adequately powered, independent randomised trial to definitively answer the question.

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.

Practice patterns of dual antiplatelet therapy after lower extremity endovascular interventions

Antiplatelet therapy is commonly prescribed following endovascular interventions. However, there is limited data regarding the regimen and duration of antiplatelet therapy following lower extremity endovascular interventions. The aim of this study was to investigate the practice patterns of dual antiplatelet therapy (DAPT) after lower extremity endovascular interventions. We identified all patients who received an endovascular intervention in the Vascular Study Group of New England (VSGNE) registry from 2010 through 2018. The antiplatelet regimen was examined at the time of discharge and follow-up. Variables predicting discharge antiplatelet therapy and duration of antiplatelet therapy were investigated. There were 13,510 (57.69%) patients discharged on DAPT, 8618 (36.80%) patients discharged on single antiplatelet therapy, and 1292 (5.51%) patients discharged without antiplatelet therapy. Patients with coronary artery disease (CAD), prior vascular bypass and endovascular intervention, preoperative statin use, stent placement compared with angioplasty, and femoropopliteal and tibial treatment were associated with higher odds of being discharged with DAPT compared with no antiplatelet therapy and single antiplatelet therapy. Of the patients discharged on DAPT who were followed up at 9–12 months and 21–24 months, 56.49% and 49.63% remained on DAPT, respectively. Only a narrow margin of the patient majority undergoing endovascular interventions was discharged with DAPT, suggesting that only a small proportion of patients undergoing endovascular intervention remain on DAPT long-term. As the number of peripheral vascular interventions continues to grow, further studies are crucial to identify the optimal duration of DAPT.

Medical adjunctive therapy for patients with chronic limb-threatening ischemia: a systematic review

INTRODUCTION

The aim of this article is to systematically review the literature on medical adjunctive therapy for patients with chronic limb-threatening ischemia (CLTI).

EVIDENCE ACQUISITION

MEDLINE, Embase, and Cochrane Database of Systematic Reviews were searched for studies published between January 1st, 2009, and June 1st, 2019. Articles that studied medical treatment of CLTI patients and reported clinical outcomes were eligible. Main exclusion criteria were case reports <20 patients, incorrect publication type, and CLTI caused by Buerger disease. The primary end point was major amputation (above the ankle) in studies with a follow-up of ≥6 months. Secondary end points were other clinical end points such as death and wound healing. Study quality was assessed according to the Downs and Black checklist.

EVIDENCE SYNTHESIS

Included were 42 articles: four focused on antiplatelet therapy, five on antihypertensive medication, 6 on lipid-lowering therapy, 16 on stem cell therapy, three on growth factors, five on prostanoids, and one study each on cilostazol, glucose-lowering therapy, spinal cord stimulation, sulodexide, and hemodilution. Calcium channel blockers, iloprost, cilostazol, and hemodilution showed significant improvement of limb salvage, but data are limited. Stem cell therapy showed no significant improvement of limb salvage but could potentially improve wound healing. Antiplatelets, antihypertensives, and statins showed significantly lower cardiovascular events rates but not evident lower major amputation rates. The quality of the studies was fair to good.

CONCLUSIONS

Certain medical therapies serve to improve limb salvage next to revascularization in CLTI patients, whereas others are important in secondary prevention. Because high quality evidence is limited, further research is needed.