A systematic review of the efficacy of aspirin monotherapy versus other antiplatelet therapy regimens in peripheral arterial disease

Optimal antiplatelet therapy after revascularization of left subclavian artery during TEVAR

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) is a minimally invasive technique used to treat type B aortic dissections. Left subclavian artery (LSA) reconstruction is required when treating patients with involvement of LSA. The best antiplatelet therapy after LSA reconstruction is presently uncertain.

METHODS

This study retrospectively analyzed 245 type B aortic dissection patients who underwent left subclavian artery revascularization during TEVAR. Out of 245 patients, 159 (64.9%) were in the single antiplatelet therapy (SAPT) group, receiving only aspirin, and 86 (35.1%) were in the dual antiplatelet therapy (DAPT) group, receiving aspirin combined with clopidogrel. During the 6-month follow-up, primary endpoints included hemorrhagic events (general bleeding and hemorrhagic strokes), while secondary endpoints comprised ischemic events (left upper limb ischemia, ischemic stroke, and thrombotic events), as well as death and leakage events. Both univariate and multivariate Cox regression analyses were performed on hemorrhagic and ischemic events, with the Kaplan-Meier method used to generate the survival curve.

RESULTS

During the six-month follow-up, the incidence of hemorrhagic events in the DAPT group was higher (8.2% vs. 30.2%, P < 0.001). No significant differences were observed in ischemic events, death, or leakage events among the different antiplatelet treatment schemes. Multivariate Cox regression analysis showed that DAPT (HR: 2.22, 95% CI: 1.07-4.60, P = 0.032) and previous chronic conditions (HR:3.88, 95% CI: 1.24-12.14, P = 0.020) significantly affected the occurrence of hemorrhagic events. Chronic conditions in this study encompassed depression, vitiligo, and cholecystolithiasis. Carotid subclavian bypass (CSB) group (HR:0.29, 95% CI: 0.12-0.68, P = 0.004) and single-branched stent graft (SBSG) group (HR:0.26, 95% CI: 0.13-0.50, P < 0.001) had a lower rate of ischemic events than fenestration TEVAR (F-TEVAR). Survival analysis over 6 months revealed a lower risk of bleeding associated with SAPT during hemorrhagic events (P = 0.043).

CONCLUSIONS

In type B aortic dissection patients undergoing LSA blood flow reconstruction after synchronous TEVAR, the bleeding risk significantly decreases with the SAPT regimen, and there is no apparent ischemic compensation within 6 months. Patients with previous chronic conditions have a higher risk of bleeding. The CSB group and SBSG group have less ischemic risk compared to F-TEVAR group.

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.

Validation of the Academic Research Consortium High Bleeding Risk (ARC-HBR) criteria in patients undergoing peripheral endovascular interventions

BACKGROUND

It remains unclear whether the Academic Research Consortium for High Bleeding Risk (ARC-HBR) criteria could apply to peripheral artery disease (PAD) patients undergoing endovascular therapy (EVT).

AIMS

We sought to evaluate the application of the ARC-HBR criteria to PAD patients undergoing EVT with contemporary drug-coated devices (DCD) for femoropopliteal artery lesions.

METHODS

Between May 2012 and December 2019, 542 consecutive patients undergoing EVT with DCD for femoropopliteal artery lesions were retrospectively analysed. The primary study endpoint was major bleeding events, defined as Bleeding Academic Research Consortium type 3 or 5.

RESULTS

Of 542 patients, 435 (80.3%) were stratified into the HBR group. The cumulative 5-year incidence of major bleeding events was significantly higher in the HBR group than in the non-HBR group (31.9% vs 2.3%; p<0.001). The 5-year major bleeding event rate gradually increased with the number of ARC-HBR criteria (≥2 major criteria: 48.6%, 1 major: 33.1%, ≥2 minor: 12.9%, and non-HBR: 2.3%; p<0.001). Major bleeding events were associated with a 5.4-fold increased risk of mortality (adjusted hazard ratio: 5.42, 95% confidence interval: 2.91-10.1; p<0.001). Severe chronic kidney disease, heart failure, and severe anaemia were predictors of major bleeding events.

CONCLUSIONS

80.3% of PAD patients undergoing EVT for femoropopliteal artery lesions with contemporary drug-coated devices met the ARC-HBR criteria. Given that major bleeding events remarkably increased the risk of mortality after EVT, the ARC-HBR criteria might be helpful for the risk stratification of PAD patients who undergo EVT with contemporary DCD.

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.

Immediate postprocedure anticoagulation with factor Xa inhibitors of venous stents for nonthrombotic venous lesions does not increase stent patency

BACKGROUND

Many clinicians will prescribe anticoagulation therapy for patients after iliac vein stenting to prevent early or late stent thrombosis. At present, it is unknown whether therapeutic anticoagulation has any effect on stent patency. Thus, we assessed the role of short-term anticoagulation on iliac vein stent patency in patients with nonthrombotic iliac vein lesions (NIVLs).

METHODS

We performed a retrospective medical record review of all iliac vein stents placed for NIVLs at the Center for Vascular Medicine from January 2018 to December 2019. We compared the stent patency in the two groups. The anticoagulation (AC) group had received rivaroxaban or apixaban postoperatively for a minimum of 90 days and were compared with a group that had received no postoperative anticoagulation (NAC). Stent patency was assessed using transabdominal ultrasound at 3, 6, 12, 18, 24, and 30 months. At the discretion of the treating physician, the patients who demonstrated thrombus layering on surveillance ultrasound scanning continued rivaroxaban or apixaban until thrombus resolution was observed. The demographics and stent location, diameter, and length were assessed. Stent patency was analyzed using life table analyses. Differences in stent patency were analyzed using GraphPad Prism, version 8, statistical software (GraphPad Software Inc, La Jolla, Calif) and the log-rank (Mantel-Cox) test.

RESULTS

The number of patients and stents in each group were as follows: AC group, 299 patients and 308 stents; and NAC group, 77 patients and 90 stents. The average age was 52.24 ± 13.44 years and 55.63 ± 14.49 years in the AC and NAC groups, respectively (P ≤ .065). Women constituted 76% of the patients in the AC group and 72% in the NAC group. The average stent diameter and length for the AC group was 20 ± 2 mm and 77 ± 13 mm and for the NAC group was 19 ± 2 mm and 82 ± 9 mm, respectively. The stents had been placed in the right common iliac vein, bilaterally, or left common iliac vein territory in 15%, 3%, and 82% in the AC group and 18%, 2%, and 80% in the NAC group, respectively. The cumulative stent patency at 30 months was 98.7% and 94.6% for the NAC and AC groups, respectively (P ≤ .83). All the stents placed were Wallstents (Boston Scientific, Marlborough, Mass). A total of eight insertion site thromboses occurred that did not affect stent patency: five in the AC group (1.6%) and three in the NAC group (4.5%; P = .15). In addition, 19 patients demonstrated evidence of thrombus layering, with 6 receiving extended anticoagulation.

CONCLUSIONS

Our data indicate that perioperative stent thrombosis in patients with NIVLs is uncommon. Thus, anticoagulation for perioperative stent thrombosis prophylaxis is not necessary. Anticoagulation should only be used for patients with insertion site thromboses and should be considered if thrombus layering is observed on surveillance scanning.

Antithrombotic Treatment for Peripheral Arterial Occlusive Disease

BACKGROUND

Patients with peripheral arterial occlusive disease (PAOD) are at elevated risk for cardiovascular events and vascular events affecting the limbs. The goals of antithrombotic treatment are to keep vessels open after revascularization, to prevent cardiovascular events, and to lessen the frequency of peripheral ischemia and of amputation.

METHODS

This review is based on pertinent publications retrieved by a selective literature search, with particular attention to meta-analyses, randomized controlled trials, and the German and European angiological guidelines.

RESULTS

Diabetes mellitus and nicotine abuse are the main risk factors for lower limb PAOD. The evidence for the efficacy and safety of antithrombotic treatment in patients with PAOD is limited, in particular, after surgical or endovascular revascularization. Intensifying antithrombotic treatment with stronger antiplatelet therapy (APT), dual antiplatelet therapy (DAPT), or antiplatelet therapy combined with anticoagulation lowers the rate of peripheral revascularization (relative risk [RR] 0.89; 95% confidence interval [0.83; 0.94]), amputation (RR 0.63; [0.46; 0.86]), and stroke (RR 0.82; [0.70; 0.97]) but raises the risk of bleeding (RR 1.23; [1.04; 1.44]). Predictors for peripheral vascular events include critical limb ischemia and having previously undergone a revascularization procedure or an amputation.

CONCLUSION

Antiplatelet therapy should only be intensified for a limited time, or if the risk of ischemia is high. Before and during intensified antiplatelet therapy, the risk of bleeding should be assessed and weighed against the risk of ischemia. No validated score is available to estimate the risk of hemorrhagic complications in patients with PAOD. New antithrombotic therapies should not be used indiscriminately, but should rather be reserved for selected groups of patients.

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.

Risk factors and prognostic impact of post-discharge bleeding after endovascular therapy for peripheral artery disease

This study evaluated the incidence, predictors, and impact of bleeding requiring hospitalization following successful endovascular therapy (EVT) for peripheral artery disease. Platelet inhibition after EVT reduces the risk of major adverse limb events but increases the risk of bleeding. The incidence of post-discharge bleeding after EVT, its independent predictors, and its prognostic importance in clinical practice have not been fully addressed. We evaluated 779 consecutive patients who underwent EVT. We found that 77 patients (9.9%) were hospitalized for major bleeding during follow-up after EVT (median 39 months, range 22-66 months), with almost half (48.1%) of the bleeding categorized as gastrointestinal bleeding. Significant predictors of post-discharge bleeding were hemodialysis (hazard ratio (HR), 3.12; 95% CI: 1.93 to 5.05; p < 0.001) and dual antiplatelet therapy (DAPT) use (HR, 1.87; 95% CI: 1.03 to 3.41; p = 0.041). During follow-up, the all-cause mortality-free survival rate was significantly worse in patients who had experienced major bleeding than in those who had not (log-rank test χ² = 54.6; p < 0.001). Cox proportional hazards analysis showed that major bleeding (HR, 2.78; 95% CI: 1.90 to 4.06; p < 0.001) was an independent predictor of all-cause death after EVT. Hospitalization for post-discharge bleeding after EVT is associated with a substantially increased risk of death, even after successful EVT. We concluded that patients' predicted bleeding risk should be considered when selecting patients likely to benefit from EVT, and that the risk should be considered especially thoroughly in hemodialysis patients.

Low Dose Rivaroxaban for Atherosclerotic Cardiovascular Diseases: A Systematic Review and Meta-analysis

Background: This study aims to explore the role of low-dose rivaroxaban (≤10 mg daily) for the treatment of atherosclerotic cardiovascular disease (ASCVD). Methods: PubMed, Embase and the Cochrane Library were searched for randomized controlled trials (RCTs) of low-dose rivaroxaban in patients with ASCVD including coronary artery disease (CAD) and peripheral artery disease (PAD). Literature screening, data extraction, and risk of bias assessment were carried out independently by two researchers. Hazard ratio (HR) and 95% confidence interval (CI) were calculated using random-effect models to determine risks of outcomes in ASCVD patients treated with rivaroxaban and comparators, and meta-analysis was conducted via Review Manager 5.3.5 software. Results: 3,768 records were obtained through literature search, and 9 articles representing 6 RCTs ultimately qualified for this study. The meta-analysis indicated that for patients with CAD, the addition of rivaroxaban (5 mg daily) to aspirin could significantly reduce the risk of major adverse cardiovascular events (MACEs) compared with aspirin alone (HR 0.81, 95% CI, 0.72 to 0.91, p = 0.0004, I² = 60%, 4 studies). For PAD patients receiving rivaroxaban (5 mg daily) plus aspirin, there was no significant reduction in the risk of MACEs (HR 0.84, 95% CI, 0.63 to 1.13, p = 0.25, I² = 74%, 2 studies); however, there was significant reduction in major adverse limb events (MALEs) (HR 0.54, 95% CI, 0.35 to 0.83, p = 0.005, one studies) and in the composite of MACEs or MALEs (HR 0.78, 95% CI, 0.64 to 0.95, p = 0.02, I² = 66%, 2 studies) when compared with patients receiving aspirin alone. Meanwhile, rivaroxaban combined with aspirin significantly increased the risk of International Society on Thrombosis and Haemostasis (ISTH) major bleeding compared with aspirin alone in patients with CAD (HR 1.74, 95% CI, 1.43 to 2.13, p < 0.00001, I² = 0%, 2 studies) and PAD (HR 1.47, 95% CI, 1.19 to 1.83, p = 0.0004, I² = 0%, 2 studies). Conclusions: Compared with standard antiplatelet therapy, the addition of a 5 mg daily dose of rivaroxaban to standard antiplatelet therapy may improve cardiovascular or limb outcomes of patients with ASCVD, with an increase in major bleeding. Patients who would benefit from the addition of low-dose rivaroxaban to antiplatelet agents and appropriate dual-pathway antithrombotic strategies should be identified in clinical practice to individualize antithrombotic therapy.

Efficacy of transarterial embolisation in patients with life-threatening spontaneous retroperitoneal haematoma

AIM

To evaluate the technical and clinical success of embolisation in patients with life-threatening spontaneous retroperitoneal haematoma (SRH) and to assess predictors of clinical outcome.

MATERIALS AND METHODS

Thirty patients (mean age: 71.9±9.8 years) with SRH underwent digital subtraction angiography (DSA). All patients received anticoagulant or antiplatelet medication or a combination of both at the time the SRH occurred.

RESULTS

Pre-interventional computed tomography angiography (CTA) revealed active retroperitoneal bleeding in 28 of 30 (93.3%) patients. DSA identified active haemorrhage in 22 of 30 patients (73.3%). Twenty-nine of 30 (96.7%) patients underwent embolisation. n-Butyl-2-cyanoacrylate (NBCA) was used in 15 patients (51.7%), coils were used in 10 patients (34.5%), and both embolic agents were used in four patients (13.8%). The technical success rate was 100%. Pre-interventional haemoglobin levels increased significantly after embolotherapy from 70.9±16.1 g/l to 87±11.3 g/l (p<0.001), whereas partial thromboplastin time decreased from 58±38 to 30±9 seconds (p<0.001) after embolotherapy. The need for transfusion of concentrated red cells decreased from 3±2.2 to 1±1.1 units (p<0.001) after the intervention. Clinical success was achieved in 19 of 29 (65.5%) patients. No major procedure-related complications occurred. Seven patients (24.1%) died within 30 days after the procedure.

CONCLUSION

Embolotherapy in patients with life-threatening SRH leads to a high technical success rate and is a safe therapeutic option. The clinical success rate was acceptable and influenced by pre-interventional coagulation status and by the amount of transfused concentrated red cells.

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

Endovascular treatment is effective for symptomatic peripheral arterial disease (PAD). Following recent device improvements, favorable long-term outcomes have been achieved in iliac arteries as well as small arteries such as the femoral and popliteal arteries.

This paper outlines the history and recent advances in endovascular treatment of peripheral vascular diseases as well as the characteristics and usage of devices. The history and the advances in endovascular treatment of peripheral vascular disease have been parallel, with the development of devices such as catheters and stents. Accordingly, endovascular treatment is now recommended in guidelines as the first-line for PAD.

Effects of dual antiplatelet therapy on graft patency after lower extremity bypass

OBJECTIVE

Current guidelines recommend single-agent antiplatelet therapy for patients with symptomatic peripheral artery disease and consideration of dual antiplatelet therapy (DAPT) after surgical revascularization. The objective of this study was both to explore prescribing patterns of single antiplatelet therapy vs DAPT after lower extremity bypass surgery and to investigate the effects of antiplatelet therapy on bypass graft patency.

METHODS

A retrospective analysis of prospectively collected nonemergent infrainguinal lower extremity bypass operations entered in the national Vascular Quality Initiative (2003-2018) with captured long-term follow-up was performed. Patients discharged on aspirin monotherapy or DAPT were identified. Linear regression investigated temporal trends in antiplatelet use. Multivariable Cox regression investigated predictors of primary, primary assisted, and secondary patency.

RESULTS

Of the 13,020 patients investigated, 52.2% were discharged on aspirin monotherapy and 47.8% on DAPT. The proportion of patients discharged on DAPT increased from 10.6% in 2003 to 60.6% in 2018 (P < .001). The DAPT cohort was younger, had higher rates of medical (hypertension, diabetes, congestive heart failure, chronic obstructive pulmonary disease) and atherosclerotic (coronary artery disease, prior coronary artery bypass graft or percutaneous coronary intervention, prior lower extremity intervention) comorbidities, and had higher risk bypass procedures (more distal targets, prior inflow bypass procedure, prosthetic conduit use). Multivariable Cox regression analysis did not show any difference between the DAPT and aspirin cohorts in primary patency (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.88-1.10; P = .78), primary assisted patency (HR, 0.93; 95% CI, 0.80-1.07; P = .30), or secondary patency (HR, 0.88; 95% CI, 0.74-1.06; P = .18). On subgroup analysis based on bypass conduit, DAPT was found to have a protective effect on patency only in the prosthetic bypass cohort (primary patency: HR, 0.81 [95% CI, 0.66-1.00; P = .05]; primary assisted patency: HR, 0.74 [95% CI, 0.58-0.94; P = .01]; and secondary patency: HR, 0.60 [95% CI, 0.44-0.82; P < .001]). No patency differences were observed on adjusted subgroup analysis for the other bypass conduits.

CONCLUSIONS

A significant and increasing proportion of patients are discharged on DAPT after lower extremity bypass revascularization. These patients represent a higher risk cohort with more medical comorbidities and higher risk bypass features. After controlling for these differences, DAPT therapy had no beneficial effect on overall bypass graft patency or major adverse limb events. However, on subgroup analysis, DAPT was associated with improved bypass graft patency in patients receiving prosthetic bypass conduits. Further study is warranted to investigate optimal duration of DAPT therapy and its possible bleeding complications in prosthetic bypass patients.

Systematic Literature Review of Randomized Trials Comparing Antithrombotic Therapy Following Revascularization Procedures in Patients With Peripheral Artery Disease

A systematic literature review was conducted to identify and summarize the clinical efficacy and safety of available antithrombotic therapies after peripheral endovascular or surgical revascularization in patients with peripheral artery disease (PAD). Five databases were searched using free-text and Emtree/Mesh terms for PAD, randomized controlled trials (RCTs), and antithrombotic therapies of interest (ie, single antiplatelet therapy, dual antiplatelet therapy, and vitamin K antagonists). Randomized controlled trials were eligible for inclusion if they assessed the risk of thrombotic events (ie, myocardial infarction, ischemic stroke, cardiovascular death, limb ischemia, or limb amputation) or safety profile (ie, minor, moderate, major, or fatal bleeding events) after revascularization. In total, 16 RCTs were identified. Only a few studies reported on treatment effects of the investigated therapies. Myocardial infarction, ischemic stroke, cardiovascular death, and amputation were reported in up to 2.3%, 2.3%, 5.6%, and 7.3% of patients, respectively. Bleeding events were observed in up to 8.4% (major) and 1.5% (fatal) of patients. Despite available treatments, patients with PAD undergoing revascularization remain at risk of thrombotic events. There is a need for new treatments that will help to optimize care for patients with symptomatic PAD undergoing revascularization.

Antithrombotic Treatments in Patients with Chronic Coronary Artery Disease or Peripheral Artery Disease: A Systematic Review of Randomised Controlled Trials

Aims

Acetylsalicylic acid (ASA) is widely used for the prevention of atherothrombotic events in patients with chronic coronary artery disease (CAD) and peripheral artery disease (PAD), but the risk of vascular events remains high. We aimed at identifying randomised controlled trials (RCTs) on antithrombotic treatments in patients with chronic CAD or PAD.

Methods

Searches were conducted on MEDLINE, EMBASE, and CENTRAL on March 1^st, 2018. This systematic review (SR) uses a narrative synthesis to summarize the evidence for the efficacy and safety of antiplatelet and anticoagulant therapies in the population of both chronic CAD or PAD patients.

Results

Four RCTs from 27 publications were included. Study groups included 15,603 to 27,395 patients. ASA alone was the most extensively studied (n = 3); other studies included rivaroxaban with or without ASA (n = 1), vorapaxar alone (n = 1), and clopidogrel with (n = 1) or without ASA (n = 1). Clopidogrel alone and clopidogrel plus ASA compared to ASA presented similar efficacy with comparable safety profile. Rivaroxaban plus ASA significantly reduced the risk of the composite of cardiovascular death, myocardial infarction, and stroke compared to ASA alone, although major bleeding with rivaroxaban plus ASA increased.

Conclusion

There is limited and heterogeneous evidence on the prevention of atherothrombotic events in patients with chronic CAD or PAD. Clopidogrel alone and clopidogrel plus ASA did not demonstrate superiority over ASA alone. A combination of rivaroxaban plus ASA may offer significant additional benefit in reducing cardiovascular outcomes, yet it may increase the risk of bleeding, compared to ASA alone.

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.

Prognostic risk factors for recurrent acute lower limb ischemia in patients treated with intra-arterial thrombolysis

OBJECTIVE

The objective of this study was to assess factors predisposing patients to recurrent acute lower limb ischemia (RALLI).

METHODS

Acute lower limb ischemia patients treated with catheter-directed thrombolysis (CDT) at Tampere University Hospital and Turku University Hospital between March 2002 and December 2015 were included. The patients' baseline demographics, comorbidities, and other characteristics were assessed retrospectively. Significant factors revealed by univariable analysis were tested in a multivariable model for associations with RALLI. A patency analysis was performed, and the risks of reocclusion were identified. The limb salvage rates after reocclusion were evaluated.

RESULTS

Altogether, 303 consecutive patients with a mean age of 71 years (standard deviation, 11.8 years) were included. Of them, 159 (52.5%) were men. A total of 164 (54.1%) native arterial and 139 (45.9%) bypass graft occlusions were initially treated with CDT. On completion of CDT, 204 additional endovascular or conventional surgical procedures on 203 patients were performed to obtain adequate distal perfusion. During a median follow-up of 40 months (interquartile range, 69 months), 40 (24.4%) cases of RALLI occurred in native arteries and 90 (64.7%) in bypass graft patients (P < .001). In native arteries, the absence of appropriate anticoagulant and antiplatelet medication was independently associated with the development of acute reocclusions (hazard ratio, 6.51) in the Cox multivariable regression analysis. The patency rates were 86.6%, 72.2%, and 68.0% at 1 year, 5 years, and 9 years, respectively. In bypass grafts, worsened tibial runoff (crural index III: hazard ratio, 2.40) was independently associated with RALLI. The respective patency rates were 60.5%, 34.0%, and 29.2% for synthetic conduits and 30.8%, 20.5%, and 13.7% for autologous vein grafts at 1 year, 5 years, and 9 years. Altogether, 38 (29.2%) major amputations were performed on patients with reocclusions. Patients with synthetic conduits demonstrated superior limb salvage rates after reocclusion in comparison to native arteries or vein grafts (P = .025).

CONCLUSIONS

Appropriate post-thrombolytic antiplatelet or anticoagulant treatment after native arterial events is of great importance, but additional data are needed to improve treatment algorithms. Adequate outflow in bypass graft patients is crucial. Patients with prosthetic bypass grafts have superior limb salvage rates after reocclusion.

Antiplatelet therapy for tibial balloon angioplasty: A clinical perspective

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

The Year in Vascular Anesthesia: Selected Highlights From 2018

This special article is the second in an annual series for the Journal of Cardiothoracic and Vascular Anesthesia that is specifically dedicated to highlights in vascular anesthesiology published in 2018. This review begins with 2 updates in preoperative medicine in the vascular surgery population, including recent publications regarding the management of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers and antiplatelet medications in the perioperative period. The next section focuses on complications related to thoracic endovascular aortic surgery, particularly as technology advances allow for endovascular repair of more complex anatomy. The final section focuses on quality in vascular surgery and evaluates recent publications that examine the safety and feasibility of fast-track endovascular aortic surgery. Even though this is only a sampling of the literature published in 2018 relevant to the cardiovascular anesthesiologist, these themes represent some of the topics most clinically relevant to the perioperative period.

Anti-platelet and anti-coagulant therapy in peripheral arterial disease prior to surgical intervention

OBJECTIVE

Peripheral artery disease is a major clinical co-morbidity that can significantly affect quality of life, especially in the presence of diabetes mellitus and older age. The focus of this literature review is on medical management, through anti-platelet and anti-coagulation, of peripheral artery disease prior to undergoing surgical or endovascular management.

METHOD

Extensive electronic literature search performed in four major databases (PubMed, SCOPUD, Embase and Ovid) to identify the published randomized and non-randomized studies that compared and discussed the management of peripheral artery disease with different anti-thrombotic agents.

RESULTS

A total of 17 studies were identified to meet the inclusion criteria of this review. Among them, 4 were systematic review and meta-analyses, 1 was observational study and 12 were randomized controlled trials. The reported outcomes in each study are summarized and reported separately within this review.

CONCLUSION

Peripheral artery disease is a complex and multifactorial clinical condition. The use of dual anti-platelets, such as aspirin and clopidogrel, are the key in preventing major cardiovascular events as well as stroke and death. Utilization of anti-coagulation such as direct oral anti-coagulants' as additional parameters for the prevention of disease progression, is paramount. Eventually, the choice of either dual-antiplatelet therapy or combined anti-coagulation with anti-platelets should be carefully considered, particularly following the most recent published debatable studies.