Management of peripheral arterial interventions with mono or dual antiplatelet therapy--the MIRROR study: a randomised and double-blinded clinical trial. Eur Radiol. 2012;22:1998-2006. [PMID: 22569995 DOI: 10.1007/s00330-012-2441-2]

Outcomes of endovascular intervention for atherosclerotic lesions confined to the popliteal artery

OBJECTIVE

Most surgeons employ an endovascular-first approach to the treatment of peripheral arterial disease (PAD), but controversy remains regarding the ideal interventions for the management of isolated popliteal artery disease (IPAD). Indeed, there are a paucity of data that compare outcomes of popliteal stents vs other peripheral vascular interventions (PVIs). The goal of this study was to evaluate outcomes of PVIs in IPAD.

METHODS

The Vascular Study Group of New England database was queried for all IPAD PVIs performed for atherosclerotic occlusive disease from 2010 to 2021. Those with at least 1 year of follow-up data available were included for analysis. The primary endpoint was 1-year freedom from a composite target lesion (TL) treatment failure that included restenosis >50% on duplex, reintervention, or ipsilateral major amputation.

RESULTS

We included 689 procedures performed on 634 patients. Of these, 250 (36.3%) were treated with plain balloons (POBA), 215 (31.2%) had stents, 170 (24.7%) had special balloons (drug-coated, cutting, or lithotripsy), and 54 (7.8%) atherectomies were performed. Stent placement was associated with lower freedom from TL treatment failure (72.6%) than special balloon (81.2%; P = .048) and atherectomy (88.9%; P = .012), but not POBA (76.8%; P = .293). On multivariable logistic regression, stents (odds ratio, 0.637; P = .021) and preoperative P2Y12 inhibitor therapy (odds ratio, 0.683; P = .048) were both associated with lower freedom from intervention failure.

CONCLUSIONS

Popliteal stent placement is associated with a higher rate of TL treatment failure at 1 year when compared with other PVIs including special balloon angioplasty and atherectomy, but not POBA, and should therefore be avoided in favor of special balloons or atherectomy whenever feasible.

Platelet function testing and clinical outcomes in peripheral arterial disease: Systematic review and narrative synthesis

OBJECTIVE

This systematic review aims to comprehensively assess the contemporary literature on platelet function testing (PFT) in individuals undergoing revascularization therapy for peripheral arterial disease (PAD). The goal is to identify whether PFT can aid in detecting antiplatelet resistance, predicting post-procedural thrombotic complications, and informing tailored treatment strategies.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a literature review was conducted using PubMed databases. Search terms included relevant medical subject headings (MeSH) terms. Eligible articles published in English between 1990 and 2023 were analyzed. Studies that examined PFT outcomes in patients with PAD after lower extremity revascularization were included.

RESULTS

Ten studies met the inclusion criteria. Various PFT methods were used, including thromboelastography with platelet mapping, multiplate analyzer, Cytochrome P450 2C19 testing, VerifyNow, corrected whole blood aggregometry, platelet function analyzer-100, and light transmission aggregometry. PFT identified individuals who were resistant or non-sensitive to antiplatelet therapy, with such patients facing increased risks of graft/stent thrombosis, amputation, and reintervention. However, substantial heterogeneity in surgical procedures, drug regimens, and testing methods was observed among the studies.

CONCLUSIONS

PFTs can play a crucial role in detecting resistance and non-sensitivity to antiplatelet drugs in patients with PAD post-revascularization. However, heterogeneity of data and methods underlines the need for standardized protocols and consensus-building among PFTs. Enhancing clinical utility and reliability could help optimize antiplatelet thromboprophylaxis, minimize thrombotic complications, and improve treatment strategies in vascular surgery. Further research is necessary to solidify the role of PFTs in guiding antiplatelet therapy post-revascularization in patients with PAD.

A Practical Guide to Understanding and Treating Peripheral Artery Disease

ABSTRACT

Peripheral arterial disease (PAD) is the third leading cause of atherosclerotic morbidity after coronary heart disease and stroke yet is widely underdiagnosed and undertreated. Treatment of risk factors such as diabetes and cigarette smoking can benefit patients with PAD. Patients should have adequate blood pressure and lipid control to decrease clinical manifestations and symptoms of PAD. Use of antithrombotic medications should be individualized to the patient depending on the presence of symptoms, revascularization, and comorbidities. All patient care providers, including physicians, pharmacists, nurse practitioners, and physician assistants, should incorporate PAD screening in their at-risk patients to improve access for appropriate earlier diagnosis, initiation of guideline directed therapy, and risk factor modification to reduce both major adverse CV and limb outcomes. The purpose of this narrative review is to provide an overview of PAD and summarize clinical trial evidence and guideline recommendations for screening and treatment to increase awareness among health care providers to ultimately have a positive impact on patient care.

Medical Therapy for Peripheral Artery Disease

PURPOSE OF REVIEW

Patients with lower extremity peripheral artery disease (PAD) are at high risk for major adverse cardiovascular events (MACE) and major adverse limb events (MALE). This manuscript will review the current evidence for medical therapy in patients with PAD according to different clinical features and the overall cardiovascular (CV) risk.

RECENT FINDINGS

The management of PAD encompasses non-pharmacologic strategies, including lifestyle modification such as smoking cessation, supervised exercise, Mediterranean diet and weight loss as well as pharmacologic interventions, particularly for high risk patients. Benefits for reduction of CV and limb outcomes have been demonstrated for new therapies, including antithrombotic therapy (i.e., low-dose rivaroxaban plus aspirin), lipid lowering therapy (i.e., proprotein convertase subtilisin/kexin type 9 inhibitors), and glucose lowering therapy (i.e., sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists). However, the adoption of these therapies in PAD remains suboptimal in practice. Implementation science studies have recently shown promising results in PAD patients. Comprehensive medical and non-medical management of PAD patients is crucial to improving patient outcomes, mitigating symptoms, and reducing the risk of MACE and MALE. A personalized approach, considering the patient's overall risk profile and preference, is essential for optimizing medical management of PAD.

Patient Factors Influencing Prescription of Antithrombotic Medication After Lower Limb Endovascular Intervention

OBJECTIVE

There is significant practice variation in the use of antithrombotic therapy after endovascular intervention for lower limb peripheral arterial disease, with differences in medication choice and duration. Prescriber decision making is complex, and patient factors have been shown to substantially contribute to prescribing variation. To determine the influence of patient factors on antithrombotic prescribing, a discrete choice experiment was distributed to vascular surgeons and trainees across Australia and Aotearoa New Zealand.

METHODS

After pilot testing, the discrete choice experiment questionnaire was distributed to 300 vascular surgeons and trainee members of the Australian and New Zealand Society for Vascular Surgery. Multinomial logistic regression models were used to analyse patient factors that had the most influence on decisions to prescribe a second antithrombotic agent, and the preferred choice of antithrombotic (clopidogrel 75 mg daily or rivaroxaban 2.5 mg twice daily) in addition to aspirin 100 mg daily. The odds ratio (OR) with 95% confidence interval (CI) reported preference strength.

RESULTS

A total of 44 questionnaires were completed between September and October 2023, reaching the 15% targeted response rate. Prescribing a second antithrombotic was more likely after femoropopliteal stenting compared with angioplasty (OR 1.89, 95% CI 1.20 - 2.13), and in chronic limb threatening ischaemia compared with intermittent claudication (OR 1.58, 95% CI 1.20 - 2.13). Most respondents preferred clopidogrel over rivaroxaban (62%), with over a third of respondents exclusively prescribing clopidogrel. Patients with stents (OR 1.77, 95% CI 1.32 - 2.37) or moderate bleeding risk (OR 1.38, 95% CI 0.97 - 1.84) were more likely to receive clopidogrel than rivaroxaban.

CONCLUSION

This study demonstrates that vascular surgeons primarily prioritise antithrombotic prescribing decisions by procedure type. Clopidogrel is more likely to be prescribed than rivaroxaban as a second agent in combination with aspirin, especially after stenting. Knowing these clinician preferences can target implementation strategies towards supporting decision making in subgroups of patients according to individual risk profiles.

Practice patterns of antiplatelet and anticoagulant therapy after fenestrated/branched endovascular aortic repair

OBJECTIVE

Antiplatelet and/or anticoagulant therapy are commonly prescribed after fenestrated/branched endovascular aortic repair (F/BEVAR). However, the optimal regimen remains unknown. We sought to characterize practice patterns and outcomes of antiplatelet and anticoagulant use in patients who underwent F/BEVAR.

METHODS

Consecutive patients enrolled (2012-2023) as part of the United States Aortic Research Consortium (US-ARC) from 10 independent physician-sponsored investigational device exemption studies were evaluated. The cohort was characterized by medication regimen on discharge from index F/BEVAR: (1) Aspirin alone OR P2Y12 alone (single-antiplatelet therapy [SAPT]); (2) Anticoagulant alone; (3) Aspirin + P2Y12 (dual-antiplatelet therapy [DAPT]); (4) Aspirin + anticoagulant OR P2Y12 + anticoagulant (SAPT + anticoagulant); (5) Aspirin + P2Y12 + anticoagulant (triple therapy [TT]); and (6) No therapy. Kaplan-Meier analysis and Cox proportional hazards modeling were used to compare 1-year outcomes including survival, target artery patency, freedom from bleeding complication, freedom from all reinterventions, and freedom from stent-specific reintervention.

RESULTS

Of the 1525 patients with complete exposure and outcome data, 49.6% were discharged on DAPT, 28.8% on SAPT, 13.6% on SAPT + anticoagulant, 3.2% on TT, 2.6% on anticoagulant alone, and 2.2% on no therapy. Discharge medication regimen was not associated with differences in 1-year survival, bleeding complications, composite reintervention rate, or stent-specific reintervention rate. However, there was a significant difference in 1-year target artery patency. On multivariable analysis comparing with SAPT, DAPT conferred a lower hazard of loss of target artery patency (hazard ratio [HR], 0.48; 95% confidence interval [CI], 0.27-0.84; P = .01). On sub-analyses of renal stents alone or visceral stents alone, DAPT no longer had a significantly lower hazard of loss of target artery patency (renal: HR, 0.66; 95% CI, 0.35-1.27; P = .22; visceral: HR, 0.31; 95% CI, 0.05-1.9; P = .21). Lastly, duration of DAPT therapy (1 month, 6 months, or 1 year) did not significantly affect target artery patency.

CONCLUSIONS

Practice patterns for antiplatelet and anticoagulant regimens after F/BEVAR vary widely across the US-ARC. There were no differences in bleeding complications, survival or reintervention rates among different regimens, but higher branch vessel patency was noted in the DAPT cohort. These data suggest there is a benefit in DAPT therapy. However, the generalizability of this finding is limited by the retrospective nature of this data, and the clinical significance of this finding is unclear, as there is no difference in survival, bleeding, or reintervention rates amongst the different regimens. Hence, an "optimal" regimen, including the duration of such regimen, could not be clearly discerned. This suggests equipoise for a randomized trial, nested within this cohort, to identify the most effective antiplatelet/anticoagulant regimen for the growing number of patients being treated globally with F/BEVAR.

Association of antiplatelet therapy with clinical outcomes in patients with peripheral artery disease

BACKGROUND

The beneficial role of dual anti-platelet therapy (DAPT) in coronary artery disease is well established. However, there is limited data describing the effects of DAPT in patients with atherosclerotic peripheral artery disease (PAD). The aim of this meta-analysis is to compare clinical outcomes associated with DAPT versus single anti-platelet therapy (SAPT) in patients with symptomatic PAD.

METHODS

We performed a literature search for studies assessing the risk of adverse cardiovascular and limb events in cohorts receiving either DAPT or SAPT. The primary endpoint was all cause mortality. The secondary endpoints included graft failure, amputation, total bleeding, severe bleeding and fatal bleeding. The search included the following databases: Ovid MEDLINE, EMBASE, Web of Science, and Google Scholar. The search was not restricted to time or publication status.

RESULTS

A total of 11 studies with 54,331 participants (24,449 on SAPT and 29,882 on DAPT) were included. Patients with PAD treated with SAPT had higher all-cause mortality compared to patients treated with DAPT (OR 1.37, 95 % CI 1.09-1.74; p < 0.01). There was no difference in risk of graft failure or amputation between patients treated with SAPT or DAPT (OR 0.9, 95 % CI 0.77-1.06; p = 0.19; OR 1.11, 95 % CI 0.88-1.41; p = 0.37). Patients treated with SAPT had lower total bleeds compared to patients treated with DAPT (OR 0.53, 95 % CI 0.36-0.77; p < 0.01). However, For SAPT plus AC vs SAPT, a total of 8 studies with 17,100 participants (3447 with SAPT plus AC and 8619 with only SAPT) were included. Patients on SAPT plus AC did not have a statistically significant difference in risk for all-cause mortality, (OR 0.91, 95 % CI 0.67-1.24; p = 0.56). SAPT plus AC had significantly lower risk of MI (OR 0.82, 95 % CI 0.69-0.97; p = 0.02), amputation (OR 0.72, 95 % CI 0.53-0.97; p = 0.03), and graft failure (OR 0.66, 95 % CI 0.48-0.93; p = 0.02). There was no significant different in risk of fatal bleeding be-tween the two groups (OR 1.60, 95 % CI 0.76-3.35; p = 0.22).

CONCLUSIONS

In patients with symptomatic PAD, a strategy of DAPT may confer a mortality benefit when compared to SAPT without significantly increasing the risk of serious bleeding events.

The effects of CYP2C19 genotype polymorphism and clopidogrel resistance on ischemic event occurrence in patients with peripheral arterial disease undergoing revascularization: A prospective cohort study

INTRODUCTION

Peripheral arterial disease (PAD) affects approximately 236 million people worldwide. Therefore, this study aimed to investigate the relationship between CYP2C19 genotype polymorphisms and clopidogrel resistance (CR) following revascularization in patients with PAD.

MATERIALS AND METHODS

In total, 345 patients who underwent PAD revascularization were monitored for five years and risk factors for ischemic events were identified. Platelet reactivity and CYP2C19 genotypes were measured, and patients were classified as normal, intermediate, or poor metabolizers based on their genotypes. The study endpoint was defined as an ischemic event, that encompassed major adverse cardiovascular or limb events, or all-cause death.

RESULTS

In this study, ischemic events following PAD revascularization were associated with patient age, prior minor amputation, the Rutherford category before revascularization, indications for revascularization, index ankle-branchial index before revascularization, CYP2C19 phenotypes, and CR. Intermediate and poor metabolism, the Rutherford category before revascularization, and CR were independent risk factors for ischemic events in patients after PAD revascularization. Similarly, intermediate and poor metabolism, the Rutherford category before revascularization, and CR were independent risk factors for ischemic events in patients with PAD after revascularization within five years. Intermediate and poor metabolizers had a higher platelet reactivity and risk of CR than normal metabolizers. However, poor metabolizers had a higher platelet reactivity and risk of CR than intermediate metabolizers. Furthermore, the hazard ratio for ischemic events increased with platelet reactivity. This effect was more prevalent in intermediate and poor metabolizers than in normal metabolizers.

CONCLUSIONS

Ischemic events in patients after PAD revascularization were affected by independent risk factors. Decreased clopidogrel metabolism increased the platelet reactivity and CR in patients after PAD revascularization. Furthermore, high platelet reactivity was associated with an increased risk of ischemic events in patients with intermediate and poor metabolism.

Optimizing platelet inhibition in peripheral artery disease: A comparison of mono-antiplatelet therapy and dual-antiplatelet therapy using thromboelastography

BACKGROUND

Antiplatelet therapy is used to prevent thrombosis in patients with peripheral artery disease (PAD) following revascularization. However, the current standard of care for these patients remains at the physician's discretion, varying from mono-antiplatelet therapy (MAPT) to dual-antiplatelet therapy (DAPT). Viscoelastic assays such as Thromboelastography with Platelet Mapping (TEG-PM) provide insight into individual coagulation profiles and measure real-time platelet function. This prospective, observational study looks at the differences in platelet function for patients on MAPT versus DAPT using TEG-PM.

METHODS

Patients with PAD undergoing revascularization were prospectively evaluated between December 2020 and June 2023. TEG-PM analysis compared platelet function for patients prescribed MAPT (aspirin or clopidogrel) at the initial encounter and DAPT (aspirin and clopidogrel) at the next visit. Platelet function measured in percent inhibition was evaluated at these visits, and within-group t-tests were performed.

RESULTS

Of the 195 patients enrolled, 486 samples were analyzed by TEG-PM. Sixty-four patients met the study criteria. At the initial visit, 52 patients had been prescribed aspirin, and 12 patients had been prescribed clopidogrel. For patients initially prescribed aspirin MAPT, an increase of 96.8%in the mean ADP platelet inhibition was exhibited when transitioning to DAPT [22.0% vs. 43.3%, p < .01], as well as an increase of 34.6%in the mean AA platelet inhibition when transitioning to DAPT [60.9% vs. 82.0%, p < .01]. For patients prescribed initial clopidogrel MAPT, an increase of 100% in AA platelet inhibition was exhibited on DAPT compared to the MAPT state [42.3% vs. 84.6%, p < .01].

CONCLUSIONS

Patients on DAPT showed a significant increase in platelet inhibition when compared to initial aspirin MAPT. A significant difference in AA %platelet inhibition was shown for patients on DAPT when compared to initial clopidogrel MAPT. The results show that patients may benefit from DAPT post-revascularization. Personalizing antiplatelet therapy with objective viscoelastic testing to confirm adequate treatment may be the next step in optimizing patient outcomes to reduce thrombosis in PAD patients.

Peripheral Vascular Disease

Peripheral artery disease is most often caused by atherosclerosis. Arterial insufficiency from atherosclerotic blockages in the limbs can impair walking distance and put patients with severe disease at risk of limb loss. Management of the disease centers around early diagnosis, supervised exercise therapy and lifestyle modification, optimizing medical care (with the goal of reducing fatal cardiac and cerebrovascular events), and revascularization.

Clinical recurrence and antiplatelet drug resistance among patients with lower limb ischemia

There is a high prevalence rate of peripheral artery disease worldwide, with estimated cases exceeding 200 million. Most patients are under-diagnosed and under-treated, and there is a lack of knowledge regarding the best therapeutic regimen and therapy duration, which leads to many cases of recurrence, complications, and amputations. This study aims to explore clinical recurrence, which was defined as the worsening of chronic peripheral artery disease requiring hospital admission, and its relationship with antiplatelet drug resistance among patients with lower limb ischemia. This cohort study includes both retrospective and prospective recruitment of patients with chronic lower limb ischemia. Platelet aggregation tests were offered to the patients. Between February 2018 and November 2020, 147 patients were recruited from King Abdullah University Hospital and followed up for at least 1 year. Platelet aggregation tests were done for 93 patients who agreed to participate in this part of the study. The prevalence of chronic lower limb ischemia was higher in young male patients who are current smokers with co-morbid diseases such as hypertension, diabetes mellitus, and/or dyslipidemia. There was a significant association only of clinical recurrence with younger age (P = .011) and with low platelets count in severe stages of the disease (P = .047). No significant association was found in terms of laboratory resistance. The clinical recurrence rates of chronic lower limb ischemia were higher in younger patients and among those with low platelet counts in the severe stages of the disease. Despite the laboratory responsiveness to anti-platelet therapy, we observed significant clinical resistance and increased recurrence rates.

Preventive Therapies in Peripheral Arterial Disease

Atherosclerosis, while initially deemed a bland proliferative process, is now recognized as a multifactorial-lipoprotein-mediated inflammation-driven pathway. With the rising incidence of atherosclerotic disease of the lower extremity arteries, the healthcare burden and clinical morbidity and mortality due to peripheral artery disease (PAD) are currently escalating. With a healthcare cost burden of over 21 billion USD and 200 million patients afflicted worldwide, accurate knowledge regarding the pathophysiology, presentation, and diagnosis of the disease is crucial. The role of lipoproteins and their remnants in atherosclerotic vessel occlusion and plaque formation and progression has been long established. This review paper discusses the epidemiology, pathophysiology, and presentation of PAD. PAD has been repeatedly noted to portend to poor cardiovascular and limb outcomes. We discuss major therapeutic avenues for the prevention of major cardiovascular adverse events and major limb adverse events in patients with PAD.

High on-treatment platelet reactivity in peripheral arterial disease: A systematic review

OBJECTIVES

To highlight current evidence pertaining to the measurement methods and prevalence of high on-treatment platelet reactivity (HTPR) in patients with PAD, as well as to evaluate the relationship between HTPR and recurrent adverse cardiovascular and limb events in PAD patients.

METHODS

A systematic review of English-language literature on HTPR in patients with PAD. An electronic literature search of PubMed and Medline was performed in May 2021.

RESULTS

A total of 29 studies with a total number of 11,201 patients with PAD were identified. HTPR during clopidogrel treatment ranges from 9.8 to 77%, and during aspirin treatment ranges from 4.1 to 50% of PAD patients. HTPR was associated with adverse clinical outcomes. The need for limb revascularisation was higher in patients with HTPR during clopidogrel use. Similarly, HTPR during aspirin use in the PAD population was predictive of adverse cardiovascular events (HR 3.73; 95% CI, 1.43-9.81; p = .007). A wide range of techniques were applied to measure platelet resistance, without consensus on cut-off values. Furthermore, differing patient populations, a variety of antiplatelet regimens, and differing clinical endpoints highlight the high degree of heterogeneity in the studies included in this review.

CONCLUSION

No consensus on technique or cut-off values for HTPR testing has been reached. Patients with HTPR are potentially at a greater risk of adverse limb-related and cardiovascular events than patients sensitive to antiplatelet therapy illustrating the need for clinical implementation of HTPR testing. Future research must aim for consistent methodology. Adaptation of antiplatelet therapy based on HTPR results requires further exploration.

Dual Antiplatelet Therapy or Antiplatelet Plus Anticoagulant Therapy in Patients with Peripheral and Chronic Coronary Artery Disease: An Updated Review

Despite evidence-based therapies, patients presenting with atherosclerosis involving more than one vascular bed, such as those with peripheral artery disease (PAD) and concomitant coronary artery disease (CAD), constitute a particularly vulnerable group characterized by enhanced residual long-term risk for major adverse cardiac events (MACE), as well as major adverse limb events (MALE). The latter are progressively emerging as a difficult outcome to target, being correlated with increased mortality. Antithrombotic therapy is the mainstay of secondary prevention in both patients with PAD or CAD; however, the optimal intensity of such therapy is still a topic of debate, particularly in the post-acute and long-term setting. Recent well-powered randomized clinical trials (RCTs) have provided data in favor of a more intense antithrombotic therapy, such as prolonged dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor or a therapy with aspirin combined with an anticoagulant drug. Both approaches increase bleeding and selection of patients is a key issue. The aim of this review is, therefore, to discuss and summarize the most up-to-date available evidence for different strategies of anti-thrombotic therapies in patients with chronic PAD and CAD, particularly focusing on studies enrolling patients with both types of atherosclerotic disease and comparing a higher- versus a lower-intensity antithrombotic strategy. The final objective is to identify the optimal tailored approach in this setting, to achieve the greatest cardiovascular benefit and improve precision medicine.

Evaluation of the MYNX CONTROL™ Arterial Closure System for Achieving Primary Hemostasis after Arterial Femoral Access Following Peripheral Arterial Interventions, Compared to the FemoSealTM Closure System

Background: In addition to manual compression, various vascular closure devices (VCD) are available to seal the puncture site following arterial vascular procedures. Purpose: To evaluate the efficacy and safety of the extravascular MYNX CONTROL closure system for achieving primary hemostasis after femoral arterial access following peripheral arterial procedures, compared to the intravascular FemoSeal Aclosure system. Patients and Methods: A retrospective analysis of consecutive patients who underwent endovascular intervention between April and November 2022 was performed. The primary endpoint was the incidence of significant puncture site complication defined as a complication resulting in medical treatment. Secondary endpoints included peri-interventional incidence of hematoma, peri-interventional changes in hemoglobin, incidence of emergency diagnostics and predictors for closure system failure. Results: Five hundred and forty-eight patients were included in this analysis. False aneurysm occurred in 18/273 cases (6.6%) following the use of the MYNX closure system, compared to 6/275 cases after using the FemoSeal closure system (2.2%, p = 0.006). The incidence of post-interventional hematoma was not significantly different (28 (10.3%) in the MYNX group versus 32 (11.6%) in the FemoSeal group, p = 0.358). Peri-interventional hemoglobin drop did not differ between groups (p = 0.449). Emergency diagnostics were not significantly performed more often in the MYNX group (14 (5.1%) versus 8 (2.9%), p = 0.134). A post-interventional duplex sonography showed stenosis at the puncture site in one patient after use of the MYNX system. For the entire cohort, oral anticoagulation was the only predictor for the failure of the closure device (p = 0.036). Conclusions: Device failure was more common after using the extravascular MYNX CONTROL system than after using the intravascular FemoSeal system. However, the need for surgical or interventional therapy due to device failure was low.

Dual Antiplatelet Therapy: A Concise Review for Clinicians

Dual antiplatelet therapy (DAPT) combines two antiplatelet agents to decrease the risk of thrombotic complications associated with atherosclerotic cardiovascular diseases. Emerging data about the duration of DAPT is being published continuously. New approaches are trying to balance the time, benefits, and risks for patients taking DAPT for established cardiovascular diseases. Short-term dual DAPT of 3-6 months, or even 1 month in high-bleeding risk patients, is equivalent in terms of efficacy and effectiveness compared to long-term DAPT for patients who experienced percutaneous coronary intervention in an acute coronary syndrome setting. Prolonged DAPT beyond 12 months reduces stent thrombosis, major adverse cardiovascular events, and myocardial infarction rates but increases bleeding risk. Extended DAPT does not significantly benefit stable coronary artery disease patients in reducing stroke, myocardial infarction, or cardiovascular death. Ticagrelor and aspirin reduce cardiovascular events in stable coronary artery disease with diabetes but carry a higher bleeding risk. Antiplatelet therapy duration in atrial fibrillation patients after percutaneous coronary intervention depends on individual characteristics and bleeding risk. Antiplatelet therapy is crucial for post-coronary artery bypass graft and transcatheter aortic valve implantation; Aspirin (ASA) monotherapy is preferred. Antiplatelet therapy duration in peripheral artery disease depends on the scenario. Adding vorapaxar and cilostazol may benefit secondary prevention and claudication, respectively. Carotid artery disease patients with transient ischemic attack or stroke benefit from antiplatelet therapy and combining ASA and clopidogrel is more effective than ASA alone. The optimal duration of DAPT after carotid artery stenting is uncertain. Resistance to ASA and clopidogrel poses an incremental risk of deleterious cardiovascular events and stroke. The selection and duration of antiplatelet therapy in patients with cardiovascular disease requires careful consideration of both efficacy and safety outcomes. The use of combination therapies may provide added benefits but should be weighed against the risk of bleeding. Further research and clinical trials are needed to optimize antiplatelet treatment in different patient populations and clinical scenarios.

Focus on Prevention: Peripheral Arterial Disease and the Central Role of the Cardiologist

Peripheral artery disease (PAD) is a manifestation of systemic atherosclerotic disease. PAD patients have a poor prognosis with an increased risk of cardiovascular (CV) events, including myocardial infarction (MI), stroke, limb ischemia and CV death; therefore, it is important to detect and treat PAD early. PAD and coronary artery disease (CAD) share a common pathogenesis and risk factors for development; therefore, cardiologists are in a unique position to screen, diagnosis and treat PAD. Moreover, PAD and CAD also share some treatment goals, including an aggressive modification of risk factors to reduce the risk of CV events. However, PAD remains an underdiagnosed and undertreated disease with medico-legal implications. As the role of cardiologists is expanding, the purpose of this review was to awaken the clinicians to the significance of PAD.

Antithrombotic Therapy in Peripheral Artery Disease: Current Evidence and Future Directions

Patients with peripheral artery disease (PAD) are at an increased risk of major adverse cardiovascular events, and those with disease in the lower extremities are at risk of major adverse limb events primarily driven by atherothrombosis. Traditionally, PAD refers to diseases of the arteries outside of the coronary circulation, including carotid, visceral and lower extremity peripheral artery disease, and the heterogeneity of PAD patients is represented by different atherothrombotic pathophysiology, clinical features and related antithrombotic strategies. The risk in this diverse population includes systemic risk of cardiovascular events as well as risk related to the diseased territory (e.g., artery to artery embolic stroke for patients with carotid disease, lower extremity artery to artery embolism and atherothrombosis in patients with lower extremity disease). Moreover, until the last decade, clinical data on antithrombotic management of PAD patients have been drawn from subanalyses of randomized clinical trials addressing patients affected by coronary artery disease. The high prevalence and related poor prognosis in PAD patients highlight the pivotal role of tailored antithrombotic therapy in patients affected by cerebrovascular, aortic and lower extremity peripheral artery disease. Thus, the proper assessment of thrombotic and hemorrhagic risk in patients with PAD represents a key clinical challenge that must be met to permit the optimal antithrombotic prescription for the various clinical settings in daily practice. The aim of this updated review is to analyze different features of atherothrombotic disease as well as current evidence of antithrombotic management in asymptomatic and secondary prevention in PAD patients according to each arterial bed.

A Systematic Review of Clopidogrel Resistance in Vascular Surgery: Current Perspectives and Future Directions

BACKGROUND

Clopidogrel resistance is a well-described phenomenon that has been linked to adverse cardiovascular events in patients with coronary artery disease. The impact of clopidogrel resistance in patient outcomes after vascular and endovascular surgery is not well-established.

METHODS

Using preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, a literature review with the medical subject headings (MeSH) terms "(clopidogrel resistance) and (vascular)", "(clopidogrel resistance) and (vascular surgery)", "(clopidogrel resistance) and (endovascular)", and "(clopidogrel resistance) and (endovascular surgery)" was performed in PubMed and Cochrane databases, to identify all peer-reviewed studies performed on clopidogrel resistance in vascular and endovascular surgery. Studies written in the English language from inception to 2022 were included. Case reports, studies with limited information, nonhuman studies, and studies not pertaining to vascular or endovascular surgery were excluded from analysis. Each study was independently reviewed by 2 qualified researchers to assess eligibility.

RESULTS

Of the 691 studies identified through the MeSH strategy, 16 studies met the inclusion criteria and were reviewed and summarized. These studies focused on extracranial cerebrovascular disease (n = 5) and peripheral arterial disease (PAD, n = 11), encompassing a total of 1,716 patients. The prevalence of clopidogrel resistance ranged from 0% to 83.3%, depending on the diagnostic assay and cutoff values used. In cerebrovascular disease, clopidogrel resistance may be associated with cerebral embolization, ischemic neurologic events, and vascular-related mortality. In PAD, clopidogrel resistance has been linked to recurrent stent thrombosis, target lesion revascularization, amputation-free survival, and all-cause mortality.

CONCLUSIONS

This systematic review provides an up-to-date summary of clopidogrel resistance in vascular and endovascular surgery. The impact of clopidogrel resistance remains incompletely investigated, and future studies are needed to clarify the role of resistance testing in patients with vascular disease.

A multicenter, randomized, open-labelled, non-inferiority trial of sustained-release sarpogrelate versus clopidogrel after femoropopliteal artery intervention

Optimal antiplatelet therapy after endovascular therapy (EVT) for peripheral artery disease is controversial. This trial aimed to evaluate whether sarpogrelate plus aspirin was non-inferior for preventing early restenosis after femoropopliteal (FP) EVT compared to clopidogrel plus aspirin. In this open-label, prospective randomized trial, 272 patients were enrolled after successful EVT for FP lesions. Patients in each group received aspirin 100 mg and clopidogrel 75 mg or sarpogrelate 300 mg orally once per day for 6 months. The primary outcome was target lesion restenosis at 6 months, tested for noninferiority. Patient characteristics and EVT patterns were similar, except for increased inflow procedures in the sarpogrelate group and increased outflow procedures in the clopidogrel group. The sarpogrelate group showed a tendency of less restenosis at 6 months than the clopidogrel group (13.0% vs. 19.1%, difference 6.1 percentage points, 95% CI for noninferiority - 0.047 to 0.169). Secondary endpoints related to safety outcomes were rare in both groups. Risks of target lesion restenosis of the two intervention arm were uniform across most major subgroups except for those with coronary artery disease. In conclusion, Sarpogrelate plus aspirin is non-inferior to clopidogrel plus aspirin in preventing early restenosis after FP EVT. Larger multi-ethnic trials are required to generalize these findings. Trial registration: National Institutes of Health Clinical Trials Registry (ClinicalTrials.gov identifier: NCT02959606; 09/11/2016).

Antithrombotische Therapie bei pAVK und Aortenerkrankungen

Patienten mit peripherer arterieller Verschlusskrankheit (pAVK) oder Aortenerkrankungen haben ein hohes Risiko für kardiovaskuläre Ereignisse. Gerinnungshemmende Medikamente verbessern die Prognose und haben daher einen hohen Stellenwert. Bei jeder gerinnungshemmenden Therapie sollte das individuelle Blutungsrisiko berücksichtigt werden und eine individuelle Nutzen-Risiko-Abwägung durchgeführt werden. Patienten mit symptomatischer pAVK sollten einen Thrombozytenaggregationshemmer (TZAH) erhalten. Bei hohem Risiko für kardiovaskuläre Ereignisse und niedrigem Blutungsrisiko wird die Kombination von Acetylsalicylsäure (ASS) 100 mg und Rivaroxaban 2 × 2,5 mg empfohlen. Liegt ein hohes Blutungsrisiko vor, ist Clopidogrel ASS vorzuziehen. Bei Patienten mit Aortenerkrankungen (z. B. komplexe Plaques, Aortenaneurysma) ist die Gabe eines TZAH indiziert. Patienten mit einer atherosklerotischen Gefäßerkrankung und Indikation für eine orale Antikoagulation wegen Vorhofflimmern oder venöser Thromboembolie sollten keinen zusätzlichen TZAH erhalten. Denn dieser erhöht das Blutungsrisiko, ohne die Prognose zu verbessern.

Antithrombotic therapy in peripheral arterial disease

Background

Patients with peripheral arterial disease (PAD) are at increased risk for major adverse cardiovascular events (MACE) such as cardiovascular death, myocardial infarction, and stroke as well as major adverse limb events (MALE) such as amputation and acute limb ischemia. Therefore, prevention of thrombotic events is crucial to improve the prognosis of PAD patients. This review article concludes current evidence and guideline recommendations about antithrombotic therapy in PAD patients.Antithrombotic therapy is highly effective to reduce MACE and MALE events in PAD patients. Recently, the concept of dual pathway inhibition (low-dose rivaroxaban plus acetylic salicylic acid (ASA) has been tested in the COMPASS and VOYAGER-PAD trial. Compared to ASA alone dual pathway inhibition was superior to prevent MACE and MALE. After peripheral revascularization, in particular the risk for acute limb ischemia was reduced. In contrast, the risk for major bleeding is increased. Therefore, current guidelines recommend the combination of low-dose rivaroxaban and ASA in PAD patients with low bleeding risk. In patients with high bleeding risk, a single antiplatelet drug (preferable clopidogrel) is indicated. In patients with atherosclerotic vascular disease and indication for oral anticoagulation, no additional antiplatelet drug is necessary, as this would increase the risk of bleeding without improving the prognosis.

Conclusion

Antithrombotic treatment reduces MACE and MALE and is recommended in all patients with PAD. Individual bleeding risk should always be considered based on the current data situation and an individual benefit-risk assessment must be carried out.

Clinical outcome of drug-coated balloons in patients with femoropopliteal chronic total occlusive lesions: results from the multicenter EAGLE study

Background

Several studies have reported the efficacy of drug-coated balloons (DCB) for simple femoropopliteal (FP) lesions. However, the effectiveness of DCB for FP chronic total occlusive lesions (CTO) is controversial. The present study investigated the clinical outcomes of DCB for FP-CTO.

Materials and methods

We retrospectively analyzed 359 limbs of 318 patients who underwent endovascular therapy with DCB for FP-CTO between July 2017 and February 2021 at seven cardiovascular centers. The primary endpoint was 12-month primary patency. The secondary endpoints were the 12-month rates of freedom from: (1) clinically-driven target lesion revascularization (CD-TLR), and (2) re-occlusion. The association of baseline characteristics with the 12-month restenosis risk was investigated using the Cox proportional hazards regression model.

Results

The 12-month rate of primary patency was 79.8% (95% confidence interval [95%CI], 75.1% to 84.8%), whereas the corresponding rates of freedom from CD-TLR and re-occlusion were 86.4% (95%CI: 82.6% to 90.4%) and 88.5% (95%CI: 84.7% to 92.4%), respectively. The bailout stent rate was 8.9%. Independent risk factors for restenosis were hemodialysis (adjusted hazard ratio, 2.18 [1.39 to 3.45]; P = 0.001), chronic limb-threatening ischemia (CLTI) (2.02 [1.33 to 3.07]; P = 0.001), and restenosis lesion (2.02 [1.32 to 3.08]; P = 0.001). Use of dual antiplatelet therapy (DAPT) was identified as a protective factor for restenosis (0.54 [0.35 to 0.82]; P = 0.003).

Conclusions

Despite the low rate of bailout stent, DCB treatment for FP-CTO was effective in real-world clinical practice. Hemodialysis, CLTI, and restenosis lesion were independent risk factors for 12-month restenosis, and the use of DAPT significantly attenuated the risk of 12-month restenosis.

Antithrombotic Therapy for Symptomatic Peripheral Arterial Disease: A Systematic Review and Network Meta-Analysis

Background

High-quality evidence from trials directly comparing single antiplatelet therapies in symptomatic peripheral arterial disease (PAD) to dual antiplatelet therapies or acetylsalicylic acid (ASA) plus low-dose rivaroxaban is lacking. Therefore, we conducted a network meta-analysis on the effectiveness of all antithrombotic regimens studied in PAD.

Methods

A systematic search was conducted to identify randomized controlled trials. The primary endpoints were major adverse cardiovascular events (MACE) and major bleedings. Secondary endpoints were major adverse limb events (MALE) and acute limb ischaemia (ALI). For each outcome, a frequentist network meta-analysis was used to compare relative risks (RRs) between medication and ASA. ASA was the universal comparator since a majority of studies used ASA as in the reference group.

Results

Twenty-four randomized controlled trials were identified including 48,759 patients. With regard to reducing MACE, clopidogrel [RR 0.78, 95% confidence interval (CI) 0.66–0.93], ticagrelor (RR 0.79, 95% CI 0.65–0.97), ASA plus ticagrelor (RR 0.79, 95% CI 0.64–0.97), and ASA plus low-dose rivaroxaban (RR 0.84, 95% CI 0.76–0.93) were more effective than ASA, and equally effective to one another. As compared to ASA, major bleedings occurred more frequently with vitamin K antagonists, rivaroxaban, ASA plus vitamin K antagonists, and ASA plus low-dose rivaroxaban. All regimens were similar to ASA concerning MALE, while ASA plus low-dose rivaroxaban was more effective in preventing ALI (RR 0.67, 95% CI 0.55–0.80). Subgroup analysis in patients undergoing peripheral revascularization revealed that ≥ 3 months after intervention, evidence of benefit regarding clopidogrel, ticagrelor, and ASA plus ticagrelor was lacking, while ASA plus low-dose rivaroxaban was more effective in preventing MACE (RR 0.87, 95% CI 0.78–0.97) and MALE (RR 0.89, 95% CI 0.81–0.97) compared to ASA. ASA plus clopidogrel was not superior to ASA in preventing MACE ≥ 3 months after revascularization. Evidence regarding antithrombotic treatment strategies within 3 months after a peripheral intervention was lacking.

Conclusion

Clopidogrel, ticagrelor, ASA plus ticagrelor, and ASA plus low-dose rivaroxaban are superior to ASA monotherapy and equally effective to one another in preventing MACE in PAD. Of these four therapies, only ASA plus low-dose rivaroxaban provides a higher risk of major bleedings. More than 3 months after peripheral vascular intervention, ASA plus low-dose rivaroxaban is superior in preventing MACE and MALE compared to ASA but again at the cost of a higher risk of bleeding, while other treatment regimens show non-superiority. Based on the current evidence, clopidogrel may be considered the antithrombotic therapy of choice for most PAD patients, while in patients who underwent a peripheral vascular intervention, ASA plus low-dose rivaroxaban could be considered for the long-term (> 3 months) prevention of MACE and MALE.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40265-022-01756-6.

Anticoagulation and Antiplatelet Agents in Peripheral Arterial Interventions

Effective revascularization of peripheral artery disease relies on periprocedural pharmacological regulation of the clotting cascade. Patient-specific factors such as cardiovascular risk factors, contraindications, and individual psychosocial factors must be considered when initiating post revascularization management. Management with anticoagulant and antiplatelet agents is discussed to guide the interventionalist on which therapy may be appropriate for their patient. While exact treatment may be institution and provider dependent, the interventionist must be familiar with the available classes of medications and how they can be prescribed in the postprocedural setting to improve cardiovascular outcomes.

Cardiovascular and Limb Events Following Endovascular Revascularization Among Patients ≥65 Years Old: An American College of Cardiology PVI Registry Analysis

Background We aimed to characterize the occurrence of major adverse cardiovascular and limb events (MACE and MALE) among patients with peripheral artery disease (PAD) undergoing peripheral vascular intervention (PVI), as well as associated factors in patients with chronic limb threatening ischemia (CLTI). Methods and Results Patients undergoing PVI in the American College of Cardiology's (ACC) National Cardiovascular Data Registry's PVI Registry who could be linked to Centers for Medicare and Medicaid Services data were included. The primary outcomes were MACE, MALE, and readmission within 1 month and 1 year following index CLTI-PVI or non-CLTI-PVI. Cox proportional hazards regression was used to identify factors associated with the development of the primary outcomes among patients undergoing CLTI-PVI. There were 1758 (49.7%) patients undergoing CLTI-PVI and 1779 (50.3%) undergoing non-CLTI-PVI. By 1 year, MACE occurred in 29.5% of patients with CLTI (n=519), and MALE occurred in 34.0% of patients with CLTI (n=598). By 1 year, MACE occurred in 8.2% of patients with non-CLTI (n=146), and MALE occurred in 26.1% of patients with non-CLTI (n=465). Predictors of MACE at 1 year in CLTI-PVI included end-stage renal disease on hemodialysis, congestive heart failure, prior CABG, and severe lung disease. Predictors of MALE at 1 year in CLTI-PVI included treatment of a prior bypass graft, profunda femoral artery treatment, end-stage renal disease on hemodialysis, and treatment of a previously treated lesion. Conclusions Patients ≥65 years old undergoing PVI experience high rates of MACE and MALE. A range of modifiable and non-modifiable patient factors, procedural characteristics, and medications are associated with the occurrence of MACE and MALE following CLTI-PVI.

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.

Vorhersage von schweren Blutungsereignissen bei Patienten mit peripherer arterieller Verschlusskrankheit: Der OAC3-PAD-Risikoscore

Obwohl Patient:innen mit einer peripheren arteriellen Verschlusskrankheit (PAVK) aufgrund ihres Komorbiditäts- und Risikoprofils ein insgesamt erhöhtes Blutungsrisiko aufweisen, standen bisher keine validierten Werkzeuge zur Vorhersage des Blutungsrisikos zur Verfügung. Erschwerend kommt hinzu, dass viele randomisierte und kontrollierte Studien zu antithrombotischen Therapien Patient:innen mit erhöhtem Blutungsrisiko ausgeschlossen haben. Anhand von Routinedaten der Krankenkasse wurde mittels Verfahren des maschinellen Lernens ein pragmatisches Vorhersagemodell entwickelt und intern validiert. Mit dem OAC³-PAD-Risikoscore wurden acht Variablen identifiziert, die das Risiko von schweren Blutungsereignissen innerhalb eines Jahres nach stationärer Behandlung der PAVK vorhersagen können. Dieser Risikoscore kann dabei helfen, eine patientenzentrierte Risiko-Nutzen-Abwägung durchzuführen, um das maximale Potenzial aus den verfügbaren antithrombotischen Therapiestrategien zu schöpfen.

Platelet reactivity testing in peripheral artery disease

DISCLAIMER

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

Oral antiplatelet therapy is routinely used to prevent adverse cardiovascular events in patients with peripheral artery disease (PAD). Several laboratory tests are available to quantify the degree of platelet inhibition following antiplatelet therapy. This article aims to provide a review of the literature surrounding platelet functional testing in patients with PAD receiving oral P2Y12 inhibitors and to offer guidance to clinicians for the use and interpretation of these tests.

SUMMARY

A literature search of PubMed and the Web of Science Core Collection database was conducted. All studies that performed platelet function testing and reported clinical outcomes in patients with PAD were included. Evaluation of the data suggests that, among the available testing strategies, the VerifyNow platelet reactivity unit (PRU) test is the most widely used. Despite numerous investigations attempting to define a laboratory threshold indicating suboptimal response to antiplatelet therapy, controversy exists about which PRU value best correlates with cardiovascular outcomes (ie, mortality, stent thrombosis, etc). In the PAD literature, the most commonly used PRU thresholds are 208 or higher and 235 or higher. Nonetheless, adjusting antiplatelet regimens based on suboptimal P2Y12 reactivity values has yet to be proven useful in reducing the incidence of adverse cardiovascular outcomes. This review examines platelet function testing in patients with PAD and discusses the interpretation and application of these tests when monitoring the safety and efficacy of P2Y12 inhibitors.

CONCLUSION

Although platelet functional tests may be simple to use, clinical trials thus far have failed to show benefit from therapy adjustments based on test results. Clinicians should be cautioned against relying on this test result alone and should instead consider a combination of laboratory, clinical, and patient-specific factors when adjusting P2Y12 inhibitor therapy in clinical practice.

A Review of Antithrombotic Therapies for Patients with Chronic Peripheral Arterial Disease and after Revascularization

Peripheral arterial disease (PAD) represents a major health issue that significantly impacts patient's survival and quality of life. In addition to limb-related events, patients with PAD have an increased risk of myocardial infarction, stroke, and death. However, compared with coronary and cerebrovascular disease, studies addressing optimal risk reduction modalities including antithrombotic therapies in patients with PAD have been underrepresented in the literature. This publication serves as a narrative review of existing evidence on the effectiveness of antithrombotic therapy in patients with PAD. In patients with chronic stable PAD or post-revascularization, antithrombotic therapies including single or dual antiplatelet agents, anticoagulation, or a combination of these treatments have been shown to reduce cardiovascular and limb events. This narrative review provides a summary of the available literature on the management of patients with PAD, categorized into treatment strategies for chronic, post-endovascular treatment, and post-open surgical revascularization and to discuss the antithrombotic protocol utilized at our institution while providing a rational for our treatment algorithm.

Antithrombotic Treatment in Lower Extremity Peripheral Arterial Disease

Lower extremity arteries might be affected by atherosclerotic peripheral arterial disease (PAD), or by embolization causing ischaemic symptoms. Patients with PAD often have widespread atherosclerosis, and progression of PAD is associated with increased risk for both other cardiovascular events and cardiovascular mortality. Peripheral arterial disease patients should therefore be offered both non-pharmacological and pharmacological secondary prevention to reduce the risk for future ischemic arterial complications. This review is focussed on the rationale for recommendations on antiplatelet and anticoagulant treatment in PAD. Asymptomatic PAD does not warrant either anticoagulant or antiplatelet treatment, whereas patients with ischaemic lower extremity symptoms such as intermittent claudication or critical limb ischemia caused by atherosclerosis should be offered platelet antiaggregation with either low dose aspirin or clopidogrel. Combined treatment with aspirin and low-dose of the direct oral anticoagulant (DOAC) rivaroxaban should be considered and weighed against bleeding risk in symptomatic PAD patients considered at high risk for recurrent ischaemic events and in patients having undergone endovascular or open surgical intervention for PAD. Patiens with cardiogenic embolization to lower extremity arteries should be recommended anticoagulant treatment with either one of the DOACs (apixaban, dabigatran, edoxaban, and rivaroxaban) or warfarin.

A Systematic Review and Meta-Analysis on the Impact of High On-Treatment Platelet Reactivity on Clinical Outcomes for Patients Taking ADP Receptor Inhibitors Following Lower Limb Arterial Endovascular Intervention

OBJECTIVE

Adenosine diphosphate (ADP) receptor inhibitors such as clopidogrel are known to be less effective at reducing platelet function for some patients because of a phenomenon called high on-treatment platelet reactivity (HTPR). However, the clinical effect of this for patients undergoing endovascular intervention for peripheral arterial disease is unclear. The aim of this study was to assess the impact of ADP receptor inhibitor HTPR on clinical outcomes following lower limb arterial endovascular intervention for peripheral arterial disease.

METHODS

A systematic review and meta-analysis was performed. Primary outcomes included all cause mortality and major bleeding. Secondary outcomes were major adverse cardiovascular events, major adverse limb events, restenosis, and target lesion revascularisation. Outcome quality was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool.

RESULTS

There were 10 eligible studies including 1 444 patients included in the meta-analysis. The most commonly tested ADP receptor inhibitor was clopidogrel (seven studies). The pooled rate of ADP receptor inhibitor HTPR was 29% (95% CI 27 - 32). The meta-analysis showed that ADP receptor inhibitor HTPR was associated with a greater risk of major adverse limb events (OR 6.25, 95% CI 2.09 - 18.68, p = .001) and a trend towards a higher all cause mortality (OR 1.71, 95% CI 0.99 - 2.94, p = .050) and more major adverse cardiovascular events (OR 4.23, 95% CI 0.46 - 38.92, p = .20) after endovascular intervention. Overall strength of evidence was very low for all outcomes.

CONCLUSION

ADP receptor inhibitor HTPR was associated with worse clinical outcomes after lower limb endovascular intervention for peripheral arterial disease. Prospective studies are required to determine the impact of modifying the antithrombotic regimen on clinical outcomes.

[Are there alternatives to dual antiplatelet therapy after stenting of peripheral arteries?]

It is estimated that more than 200 million people worldwide suffer peripheral artery disease and the rate of amputations remains at a high level. The basis of treatment is timely revascularization wherein the fraction of interventions performed endovascularly has steadily been growing both in Russia and abroad. Nevertheless, the parameters of long-term patency of endovascular reconstructions of the infrainguinal segment are still inferior to open interventions. In order to select an optimal method of revascularization and to predict the duration of patency of the reconstruction modern clinical guidelines suggest using the GLASS and WIfI scales, which may improve the remote results of the intervention. Moreover, modern paclitaxel-coated stents and balloons may help increase primary patency of the reconstruction after endovascular procedures. A not less important method of improving remote results of endovascular treatment of patients with peripheral artery disease is considered to be the use of contemporary regimens of antithrombotic therapy. The VOYAGER PAD trial showed that in patients with peripheral artery disease after endured revascularization of lower limbs rivaroxaban prescribed at a dose of 2.5 mg twice daily in a combination with conventional antithrombocytic therapy made it possible to decrease the risk of such ischaemic complications as acute limb ischaemia, major amputation, myocardial infarction, ischaemic stroke and death of cardiovascular causes.

Efficacy and Safety of Rivaroxaban Compared with Other Therapies Used in Patients with Peripheral Artery Disease Undergoing Peripheral Revascularization: A Systematic Literature Review and Network Meta-Analysis

Background

The guidelines on antithrombotic treatment in patients with symptomatic peripheral artery disease (PAD) undergoing peripheral revascularization of the lower extremities were developed based on heterogeneous trials, assessing various dose regimens and recruiting patients who were subjected to different revascularization procedures.

Objective

To compare efficacy and safety of treatments used in patients with PAD undergoing peripheral revascularization accounting for between-trial heterogeneity and large dispersion of the quality of evidence.

Methods

A systematic literature review of randomised controlled trials (RCTs) recruiting adult patients with PAD receiving antithrombotics was conducted until January 2020. Hazard ratios (HR) were pooled using Bayesian network meta-analysis. The estimated between-treatment effects were presented as HR together with 95% credible intervals. The base case analysis included studies recruiting patients following recent peripheral revascularization, who received treatment regimens administered within the recommended therapeutic window, while a sensitivity scenario included all identified trials.

Results

Thirteen RCTs were identified (8 RCTs enrolled patients following peripheral revascularization and 5 RCTs regardless of the previous revascularization). Five trials, recruiting an overall of 8349 patients, were considered for the base case analysis. Of those, 6564 patients were recruited in the VOYAGER PAD trial comparing rivaroxaban plus aspirin (RIV plus ASA) versus ASA. RIV plus ASA was associated with a lower risk of repeated peripheral revascularization versus ASA monotherapy (HR = 0.88 [0.79, 0.99]), however having a trend towards an increased rate of major bleeding (HR = 1.43 [0.98, 2.11]). There was no evidence for differences between RIV plus ASA and dual antiplatelet therapy and vitamin K antagonists plus ASA. Similar results were observed in sensitivity analyses.

Conclusions

RIV plus ASA is associated with reduced risk of revascularization compared with ASA monotherapy, but the evidence for other comparators, in particular antiplatelet regimens, was insufficient to guide treatment decisions and highlights the challenge in establishing the magnitude of comparative efficacy using existing RCTs.

Antithrombotic Therapy in Peripheral Artery Disease: Stepping in the Right Direction

We reviewed the various antithrombotic therapies available to treat peripheral artery disease (PAD). A literature review using the PubMed and MEDLINE databases used the following keywords: antithrombotic therapy, anticoagulation, peripheral artery disease, and peripheral vascular disease. Randomized studies written in English that assessed the use of antithrombotic therapy in patients with PAD were evaluated. PAD is a worldwide condition that limits blood flow in the lower extremities, leading to a risk of major adverse cardiovascular events and major adverse limb events. Antithrombotic therapy is necessary to prevent these complications, and the choice of therapy depends upon the stage of disease progression. For symptomatic patients in the beginning stage, single antiplatelet therapy (SAPT) is the preferred therapy, specifically, aspirin. For patients undergoing endovascular revascularization, the preferred therapy is dual antiplatelet therapy using aspirin and clopidogrel combined for at least the first month followed by long-term SAPT. For patients undergoing surgical revascularization, the preferred choice of therapy depends upon the type of graft used, with better results obtained with antiplatelet therapy for prosthetic grafts and anticoagulation for venous grafts. New studies have shown that therapy using both antiplatelets and anticoagulation in the form of aspirin plus low-dose rivaroxaban can reduce complications in all three patient populations, which has paved the way for future studies featuring direct oral anticoagulants with the potential to change current guideline recommendations.

Antithrombotic therapies in aortic and peripheral arterial diseases in 2021: a consensus document from the ESC working group on aorta and peripheral vascular diseases, the ESC working group on thrombosis, and the ESC working group on cardiovascular pharmacotherapy

The aim of this collaborative document is to provide an update for clinicians on best antithrombotic strategies in patients with aortic and/or peripheral arterial diseases. Antithrombotic therapy is a pillar of optimal medical treatment for these patients at very high cardiovascular risk. While the number of trials on antithrombotic therapies in patients with aortic or peripheral arterial diseases is substantially smaller than for those with coronary artery disease, recent evidence deserves to be incorporated into clinical practice. In the absence of specific indications for chronic oral anticoagulation due to concomitant cardiovascular disease, a single antiplatelet agent is the basis for long-term antithrombotic treatment in patients with aortic or peripheral arterial diseases. Its association with another antiplatelet agent or low-dose anticoagulants will be discussed, based on patient's ischaemic and bleeding risk as well therapeutic paths (e.g. endovascular therapy). This consensus document aims to provide a guidance for antithrombotic therapy according to arterial disease localizations and clinical presentation. However, it cannot substitute multidisciplinary team discussions, which are particularly important in patients with uncertain ischaemic/bleeding balance. Importantly, since this balance evolves over time in an individual patient, a regular reassessment of the antithrombotic therapy is of paramount importance.

Advances in Revascularization for Peripheral Artery Disease: Revascularization in PAD

Effective revascularization of the patient with peripheral artery disease is about more than the procedure. The approach to the patient with symptom-limiting intermittent claudication or limb-threatening ischemia begins with understanding the population at risk and variation in clinical presentation. The urgency of revascularization varies significantly by presentation; from patients with intermittent claudication who should undergo structured exercise rehabilitation before revascularization (if needed) to those with acute limb ischemia, a medical emergency, who require revascularization within hours. Recent years have seen the rapid development of new tools including wires, catheters, drug-eluting technology, specialized balloons, and biomimetic stents. Open surgical bypass remains an important option for those with advanced disease. The strategy and techniques employed vary by clinical presentation, lesion location, and lesion severity. There is limited level 1 evidence to guide practice, but factors that determine technical success and anatomic durability are largely understood and incorporated into decision-making. Following revascularization, medical therapy to reduce adverse limb outcomes and a surveillance plan should be put in place. There are many hurdles to overcome to improve the efficacy of lower extremity revascularization, such as restenosis, calcification, microvascular disease, silent embolization, and tools for perfusion assessment. This review highlights the current state of revascularization in peripheral artery disease with an eye toward technologies at the cusp, which may significantly impact current practice.

Antithrombotic regimens in females with symptomatic lower extremity peripheral arterial disease: protocol for a systematic review and meta-analysis

INTRODUCTION

Patients with peripheral arterial disease (PAD) are at increased risk for systemic arterial thromboembolic events. Females represent a unique subset of patients with PAD, who differ from males in important ways: they have smaller diameter vessels, undergo lower extremity bypass less frequently and experience higher rates of graft occlusion, amputation and mortality than males. Females also trend towards higher rates of major coronary events and cardiovascular mortality. Current guidelines recommend monoantiplatelet therapy (MAPT) for secondary prevention in patients with symptomatic PAD. However, indications for more intensive antithrombotic therapy in this cohort-especially among females who are frequently under-represented in randomised controlled trials (RCTs)-remain unclear. As newer antithrombotic therapies emerge, some RCTs have demonstrated differential effects in females versus males. A systematic review is needed to quantify the rates of arterial thromboembolic and bleeding events with different antithrombotic regimens in females with symptomatic PAD.

METHODS AND ANALYSIS

We will search MEDLINE, Embase and the Cochrane Central Register of Controlled trials for published RCTs that include females with symptomatic PAD and compare full dose anticoagulation±antiplatelet therapy, dual pathway inhibition or dual antiplatelet therapy with MAPT. Title, abstract and full-text screening will be conducted in duplicate by three reviewers. Authors will be contacted to obtain sex-stratified outcomes as needed. Risk of bias will be assessed using the Cochrane Risk of Bias tool. Data will be extracted by independent reviewers and confirmed by a second reviewer. Quantitative synthesis will be conducted using Review Manager (RevMan) V.5 for applicable outcomes data. Planned subgroup analysis by PAD severity, vascular intervention and indication for antithrombotics will be conducted where data permits.

ETHICS AND DISSEMINATION

Ethics approval is waived as the study does not involve primary data collection. This review will be submitted for publication in a peer-reviewed journal and for presentation at national and international scientific meetings.

TRIAL REGISTRATION NUMBER

This protocol was registered with the PROSPERO International Prospective Register of Systematic Reviews (ID# CRD42020196933).

The Role for Combined Antithrombotic Therapy With Platelet and Coagulation Inhibition After Lower Extremity Revascularization

Evidence for antithrombotic treatment following lower extremity revascularization (LER) for peripheral artery disease (PAD) is limited, leading to weak and conflicting guideline recommendations and heterogeneous practice patterns. This variability in post-LER antithrombotic treatment raises quality-of-care issues that have long been under-studied. This Viewpoint reviews the most updated guidelines, currently-available evidence, and contemporary data about practice patterns and practitioner opinions in this area. Particular attention is paid to distinctions between antiplatelet therapy, anticoagulant therapy, and combination therapy in light of the recent VOYAGER-PAD (Vascular Outcomes Study of ASA [acetylsalicylic acid] Along with Rivaroxaban in Endovascular or Surgical Limb Revascularization for PAD) trial. The implications of VOYAGER-PAD pertaining to various subgroups of patients undergoing LER are explored. Overall, this Viewpoint argues for consideration of post-LER therapy targeted at both platelet function and the coagulation cascade, though further LER-specific analyses, including expected VOYAGER-PAD sub-analyses, are needed.

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.

Outcomes of Lower Extremity Endovascular Revascularization: Potential Predictors and Prevention Strategies

Peripheral artery disease (PAD) is a manifestation of atherosclerosis, which may affect arteries of the lower extremities. The most dangerous PAD complication is chronic limb-threatening ischemia (CLTI). Without revascularization, CLTI often causes limb loss. However, neither open surgical revascularization nor endovascular treatment (EVT) ensure long-term success and freedom from restenosis and revascularization failure. In recent years, EVT has gained growing acceptance among all vascular specialties, becoming the primary approach of revascularization in patients with CLTI. In clinical practice, different clinical outcomes after EVT in patients with similar comorbidities undergoing the same procedure (in terms of revascularization technique and localization of the disease) cause unsolved issues that need to be addressed. Nowadays, risk management of revascularization failure is one of the major challenges in the vascular field. The aim of this literature review is to identify potential predictors for lower extremity endovascular revascularization outcomes and possible prevention strategies.

Medical therapy for cardiovascular and limb-related risk reduction in critical limb ischemia

Critical limb ischemia (CLI) constitutes the most advanced form of peripheral artery disease (PAD) and is characterized by ischemic rest pain, tissue loss and/or gangrene. Optimized medical care and risk factor modification in addition to revascularization could reduce the incidence of cardiovascular events and major adverse limb events, improving patients' quality of life and promising higher survival rates. Adequate adherence to cardioprotective medications, including antithrombotic therapy (e.g., antiplatelets, anticoagulants), cholesterol-lowering agents (e.g., statins, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors), angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs), and smoking cessation should be strongly encouraged for patients with CLI. This review examines these guideline-recommended therapies in terms of cardiovascular and limb-related risk reduction in patients with CLI.

[Antithrombotic therapy after peripheral revascularization]

Patients with lower extremity arterial disease are at increased risk for cardiovascular events. Antithrombotic therapy improves prognosis in these patients especially after peripheral revascularization. After endovascular revascularization duale anti-platelet therapy with Aspirin and Clopidogrel is used for up to 3 months in most cases, although there is only little evidence for this practice. Following peripheral bypass grafting most guidelines recommend single anti-platelet therapy. In some patients, anticoagulation with Vitamin K antagonists or dual anti-platelet therapy is indicated. But this practice is also based on small studies. The Vascular Outcomes Study of ASA Along With Rivaroxaban in Endovascular or Surgical Limb Revascularization for Peripheral Artery Disease (VOYAGER PAD) study is the largest randomized trial concerning antithrombotic therapy after peripheral revascularization. In total 6564 patients were included after successful surgical or endovascular lower-extremity revascularization. Rivaroxaban 2.5 mg twice daily plus Aspirin 100 mg reduced cardiac and peripheral events compared with Aspirin 100 mg alone with increased risk for relevant but not for critical bleeding complications. In addition to antithrombotic medication risk factor management and regular follow-up examinations are important improve long-term prognosis after peripheral revascularization.

Importance of the Results of VOYAGER PAD Trial for Clinical Practice

Пациенты с заболеваниями периферических артерий (ЗПА), перенесшие открытые реконструктивные или эндоваскулярные вмешательства, входят в группу повышенного риска ишемических осложнений. В то время как очевидные преимущества интенсификации антитромботической терапии были продемонстрированы после реваскуляризации коронарных артерий при ишемической болезни сердца, указанный подход до недавнего времени не находил достаточных подтверждений у пациентов с ЗПА. Однако результаты исследований ATLAS ACS-TIMI 51 и COMPASS доказали целесообразность применения новой антитромботической стратегии – добавление «сосудистой» дозы ривароксабана к стандартной антитромбоцитарной терапии, что позволило снизить риск ишемических осложнений у пациентов, перенесших острый коронарный синдром, а также в случаях стабильного течения атеросклеротической болезни, в том числе ЗПА. Вместе с тем неизученным оставался вопрос относительно преимуществ такой терапии в популяции пациентов с ЗПА, которые перенесли открытую или эндоваскулярную реваскуляризацию нижних конечностей. В настоящей статье отражены ключевые положения исследования VOYAGER PAD, касающиеся высокой эффективности и приемлемой безопасности ривароксабана в сочетании с аспирином после периферических артериальных реконструктивных вмешательств.

Patients with peripheral artery disease (PAD), who underwent lower extremity revascularization, are at high risk of ischemic events. While intensification of antithrombotic therapy after revascularization has demonstrated the benefit in coronary disease population, this approach has not been well- studied or proven in PAD. Recent ATLAS ACS-TIMI 51 and COMPASS trials proved that the treatment strategy of rivaroxaban added to the background antiplatelet therapy reduced ischemic risk in patients, who had acute coronary syndromes, as well as in patients with stable atherosclerotic vascular disease, including PAD. Whether these benefits extend to the population of patients with symptomatic lower extremity PAD, who undergo revascularization, was the objective of the VOYAGER PAD trial. The final results of the VOYAGER PAD study revealed the effectiveness and acceptable safety of combined antithrombotic therapy after revascularization of peripheral arteries.