Acute Limb Ischemia in Peripheral Artery Disease

Arm and ankle blood pressure indices, and peripheral artery disease, and mortality: a cohort study

BACKGROUND AND AIMS

Few studies have compared arm and ankle blood pressures (BPs) with regard to peripheral artery disease (PAD) and mortality. These relationships were assessed using data from three large prospective clinical trials.

METHODS

Baseline BP indices included arm systolic BP (SBP), diastolic BP (DBP), pulse pressure (arm SBP minus DBP), ankle SBP, ankle-brachial index (ABI, ankle SBP divided by arm SBP), and ankle-pulse pressure difference (APPD, ankle SBP minus arm pulse pressure). These measurements were categorized into four groups using quartiles. The outcomes were PAD (the first occurrence of either peripheral revascularization or lower-limb amputation for vascular disease), the composite of PAD or death, and all-cause death.

RESULTS

Among 40 747 participants without baseline PAD (age 65.6 years, men 68.3%, diabetes 50.2%) from 53 countries, 1071 (2.6%) developed PAD, and 4955 (12.2%) died during 5 years of follow-up. Incident PAD progressively rose with higher arm BP indices and fell with ankle BP indices. The strongest relationships were noted for ankle BP indices. Compared with people whose ankle BP indices were in the highest fourth, adjusted hazard ratios (95% confidence interval) for each lower fourth were 1.64 (1.31-2.04), 2.59 (2.10-3.20), and 4.23 (3.44-5.21) for ankle SBP; 1.19 (0.95-1.50), 1.66 (1.34-2.05), and 3.34 (2.75-4.06) for ABI; and 1.41 (1.11-1.78), 2.04 (1.64-2.54), and 3.63 (2.96-4.45) for APPD. Similar patterns were observed for mortality. Ankle BP indices provided the highest c-statistics and classification indices in predicting future PAD beyond established risk factors.

CONCLUSIONS

Ankle BP indices including the ankle SBP and the APPD best predicted PAD and mortality.

2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia).

METHODS

A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate.

STRUCTURE

Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.

Quantitative Benefit-Risk Evaluation of Rivaroxaban in Patients After Peripheral Arterial Revascularization: The VOYAGER PAD Trial

BACKGROUND

The VOYAGER PAD (Efficacy and Safety of Rivaroxaban in Reducing the Risk of Major Thrombotic Vascular Events in Subjects With Symptomatic Peripheral Artery Disease Undergoing Peripheral Revascularization Procedures of the Lower Extremities) trial compared rivaroxaban (2.5 mg twice a day) plus aspirin with aspirin alone in patients with symptomatic peripheral artery disease requiring endovascular or surgical limb revascularization, with 50% receiving clopidogrel background therapy. The New Drug Indication application includes benefit-risk assessments using clinical judgment to balance benefits against risks. During its review, the US Food and Drug Administration requested additional quantitative benefit-risk analyses with formal weighting approaches.

METHODS AND RESULTS

Benefits and risks were assessed using rate differences between treatment groups (unweighted analysis). To account for clinical importance of the end points, a multi-criteria decision analysis was conducted using health state utility values as weights. Monte Carlo simulations incorporated statistical uncertainties of the event rates and utility weights. Intent-to-treat and on-treatment analyses were conducted. For unweighted intent-to-treat analyses, rivaroxaban plus aspirin would result in 120 (95% CI, -208 to -32) fewer events of the primary composite end point (per 10 000 patient-years) compared with aspirin alone. Rivaroxaban caused an excess of 40 (95% CI, 8-72) Thrombolysis in Myocardial Infarction major bleeding events, which was largely driven by nonfatal, nonintracranial hemorrhage Thrombolysis in Myocardial Infarction major bleeding events. For weighted analyses, rivaroxaban resulted in the utility equivalent of 13.7 (95% CI, -85.3 to 52.6) and 68.1 (95% CI, 7.9-135.7) fewer deaths per 10 000 patient-years (intent-to-treat and on-treatment, respectively), corresponding to probabilities of 64.4% and 98.7%, respectively, that benefits outweigh risks favoring rivaroxaban per Monte Carlo simulation.

CONCLUSIONS

These analyses show a favorable benefit-risk profile of rivaroxaban therapy in the VOYAGER PAD trial, with findings generally consistent between the unweighted and weighted approaches.

Paradigm Shift of Interventional Strategies and Outcomes for Acute Limb Ischemia Post-Pandemic

PURPOSE

We performed a large-scale comparison of patients treated for acute limb ischemia (ALI) in the pre-COVID (2017-2019) and COVID (2020-2022) eras to evaluate changes in interventional strategies and compare factors associated with adverse outcomes. We sought to characterize patient outcomes in an evolving ALI treatment algorithm in response to pandemic-associated presentation delays and rapid technological advancements in mechanical thrombectomy (MT).

METHODS

Using the TriNetX global research network, we conducted a multicenter query across 80 health care organizations (HCOs) spanning 4 countries for patients treated for ALI. Propensity score matching was performed to account for comorbidities. Risk of adverse outcomes within 30 days was calculated for each era, including re-intervention (RI30), major/minor amputation, and death. Patients were then stratified by initial intervention: open revascularization (OR), MT, or catheter-directed thrombolysis and adjunctive endovascular procedures alone (CDT/EP). Risk of adverse outcomes was compared between treatment groups of the same era.

RESULTS

After propensity score matching, the pre-COVID era and COVID era cohorts included 7344 patients each. COVID era patients experienced a statistically significant higher risk of 30-day mortality (RR=1.211, p=0.027). Mechanical thrombectomy interventions were performed more frequently in the COVID era (RR=1.314, p<0.0001). Comparing outcomes between treatment groups, MT patients required RI30 more than OR patients (pre-COVID: RR=2.074, p=0.006; COVID: RR=1.600, p=0.025). Open revascularization patients had higher 30-day mortality (pre-COVID: RR=2.368, p<0.0001; COVID: RR=2.013, p<0.0001) and major amputations (pre-COVID: RR=2.432, p<0.0001; COVID: RR=2.176, p<0.0001) than CDT/EP. Pre-COVID CDT/EP patients were at higher risk for RI30 (RR=1.449, p=0.005) and minor amputations (RR=1.500, p=0.010) than OR. The MT group had higher major amputation rates than CDT/EP (pre-COVID: RR=2.043, p=0.019; COVID: RR=1.914, p=0.007). COVID-era MT patients had greater 30-day mortality (RR=1.706, p=0.031) and RI30 (RR=1.544, p=0.029) than CDT/EP.

CONCLUSION

Significant shifts toward an MT-based approach have been observed in the last 3 years. Although MT required more RI30 than OR, there was no associated consequence of mortality and limb salvage. The increased mortality seen among COVID-era patients could be explained by delayed presentation, as well as poorly understood pro-thrombogenic or pro-inflammatory mechanisms related to the first waves of COVID. More research is necessary to determine an optimal treatment algorithm.

CLINICAL IMPACT

Comorbid risk factors and severity of ischemia must be carefully considered before selecting an interventional strategy to prevent adverse outcomes and maximize limb salvage. Open revascularization strategies are associated with increased mortality and limb loss compared to less-invasive thrombolytic therapy alone. Mechanical thrombectomy (MT)-based approaches have been increasingly used in the last 3 years. Patients receiving MT are more likely to require reintervention within 30 days.

Methods, design, and initial results of an angiographic core lab from VOYAGER-PAD

Background: Anatomy is critical in risk stratification and therapeutic decision making in coronary disease. The relationship between anatomy and outcomes is not well described in PAD. We sought to develop an angiographic core lab within the VOYAGER-PAD trial. The current report describes the methods of creating this core lab, its study population, and baseline anatomic variables. Methods: Patients undergoing lower-extremity revascularization for symptomatic PAD were randomized in VOYAGER-PAD. The median follow up was 2.25 years. Events were adjudicated by a blinded Clinical Endpoint Committee. Angiograms were collected from study participants; those with available angiograms formed this core lab cohort. Angiograms were scored for anatomic and flow characteristics by trained reviewers blinded to treatment. Ten percent of angiograms were evaluated independently by two reviewers; inter-rater agreement was assessed. Clinical characteristics and the treatment effect of rivaroxaban were compared between the core lab cohort and noncore lab participants. Anatomic data by segment were analyzed. Results: Of 6564 participants randomized in VOYAGER-PAD, catheter-based angiograms from 1666 patients were obtained for this core lab. Anatomic and flow characteristics were collected across 16 anatomic segments by 15 reviewers. Concordance between reviewers for anatomic and flow variables across segments was 90.5% (24,417/26,968). Clinical characteristics were similar between patients in the core lab and those not included. The effect of rivaroxaban on the primary efficacy and safety outcomes was also similar. Conclusions: The VOYAGER-PAD angiographic core lab provides an opportunity to correlate PAD anatomy with independently adjudicated outcomes and provide insights into therapy for PAD. (ClinicalTrials.gov Identifier: NCT02504216).

Variability in guideline-directed medical therapy across sites and operators and long-term mortality and amputation outcomes risk in patients undergoing peripheral vascular interventions

BACKGROUND

The use of guideline-directed medical therapy (GDMT) in patients undergoing peripheral vascular interventions (PVIs) decreases the risk of death and amputation and may decrease hospital readmissions. The variability of GDMT prescription across sites and operators and the proportionality of risk is not well understood. We aimed to study the association between variability of GDMT prescription at the site and operator level and outcomes (including 90-day readmissions and 24-month all-cause mortality and major amputation).

METHODS

We examined GDMT discharge rates in PVIs performed between 2017 and 2018 using Medicare-linked Vascular Quality Initiative registry. GDMT included a statin, antiplatelet therapy, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACE-i/ARB) if hypertensive. Quartiles (Q1-4) of GDMT rates were documented by operators and sites and variability was quantified using median odds ratios (MOR) and intraclass correlation (ICC). The association between lower GDMT rates (per 10%) by sites and operators with 90-day readmission were calculated using logistic regression, and with 24-month mortality and major amputation using parametric survival model. Models were adjusted for patient-level factors and included sites and operators nested within sites as 2 random effects.

RESULTS

GDMT rates for 17,147 patients across 223 sites and 1,263 operators ranged from 0% to 38% (Q1, MOR 1.43, 95%CI 1.39-1.47, P ≤ .001) to 57%-100% (Q4, MOR 1.48, 95%CI 1.44-1.51, P ≤ .001). Four percent of variance in GDMT use was explained by sites (ICC 3.9, 95%CI 2.9-5.3) and operators (ICC 4.1, 95%CI 3.1-5.4). A dose-response relationship was noted between lower GDMT rates and increased risk of 90-day readmission risk by sites (P = .021) and operators (P < .001). Lower GDMT prescription by site was associated with higher risk of 24-month mortality (HR = 1.07, 95%CI 1.02-1.13) and major amputation (HR = 1.08, 95%CI 1.01-1.15). Similar associations were found for GDMT use by provider (mortality HR = 1.05, 95%CI 1.02-1.08 and amputation HR = 1.04, 95%CI 1.00-1.08).

CONCLUSION

Both at the operator and health system level, there was significant variability in GDMT prescription following PVI, proportionally translating into risk for readmission, mortality, and major amputation. Targeted quality efforts should prioritize both operator and site levels to improve GDMT use and outcomes for patients undergoing PVI.

Development and validation of a major adverse limb events prediction model for peripheral arterial disease with frailty

OBJECTIVE

To investigate the risk factors for major limb adverse events (MALE) in peripheral arterial disease (PAD) combined with frailty and to develop and validate a risk prediction model of MALE.

METHODS

This prospective study was performed in the vascular surgery department of patients in six hospitals in southwest China. Prospective collection of patients with PAD combined with frailty from February 1 to December 20, 2021, with MALE as the primary outcome, and followed for 1 year. The cohort was divided into a development cohort and a validation cohort. In the development cohort, a multivariate risk prediction model was developed to predict MALE using random forests for variable selection and multivariable Cox regression analysis. The model is represented by a visualized nomogram and a web-based calculator. The model performance was tested with the validation cohort and assessed using the C-statistic and calibration plots.

RESULTS

A total of 1179 patients were prospectively enrolled from February 1 to December 20, 2021. Among 816 patients with PAD who were included in the analysis, the median follow-up period for this study was 9 ± 4.07 months, the mean age was 74.64 ± 9.43 years, and 249 (30.5%) were women. Within 1 year, 222 patients (27.2%) developed MALE. Target lesion revascularizations were performed in 99 patients (12.1%), and amputations were performed in 131 patients (16.1%). The mortality rate within the whole cohort was 108 patients (13.2%). After controlling for competing risk events (death), the cumulative risk of developing MALE was not statistically different. Prealbumin (hazard ratio [HR], 0.6; 95% confidence interval [CI], 0.41-0.89; P = .010), percutaneous coronary intervention (HR, 2.31; 95% CI, 1.26-4.21; P = .006), Rutherford classification (HR, 1.77; 95% CI, 1.36-2.31; P < .001), white blood cell (HR, 1.85; 95% CI, 1.20-2.87; P = .005), high altitude area (HR, 3.1; 95% CI, 1.43-6.75; P = .004), endovascular treatment (HR, 10.2; 95% CI, 1.44-72.5; P = .020), and length of stay (HR, 1.01; 95% CI, 1.00-1.03; P = .012) were risk factors for MALE. The MALE prediction model had a C-statistic of 0.76 (95% CI, 0.70-0.79). The C-statistic was 0.68 for internal validation and 0.66 for external validation for the MALE prediction model. The MALE prediction model for PAD presented an interactive nomogram and a web-based network calculator.

CONCLUSIONS

In this study, the MALE prediction model has a discriminative ability to predict MALE among patients with PAD in frailty. The MALE model can optimize clinical decision-making for patients in PAD with frailty.

Causal effect of atrial fibrillation on pulmonary embolism: a mendelian randomization study

Atrial fibrillation (AF) can increase thrombosis, especially arterial thrombosis, and some studies show that AF patients have a higher risk of developing pulmonary embolism (PE). The objective of our study is to investigate whether there is a direct causal effect of AF on PE. A two-sample Mendelian randomization (MR) approach was utilized to determine whether there is a causal relationship between AF and PE. European population-based consortia provided statistical data on the associations between Single Nucleotide Polymorphisms (SNPs) and relevant traits. The AF dataset was obtained from genome-wide association studies (GWAS) comprising 60,620 cases and 970,216 controls, while a GWAS of 1846 cases and 461,164 controls identified genetic variations associated with PE. Estimation of the causal effect was mainly performed using the random effects inverse-variance weighted method (IVW). Additionally, other tests such as MR-Egger intercept, MR-PRESSO, Cochran's Q test, "Leave-one-out," and funnel plots were conducted to assess the extent of pleiotropy and heterogeneity. Using 70 SNPs, there was no evidence to suggest an association between genetically predicted AF and risk of PE with multiplicative random-effects IVW MR analysis (odds ratio = 1.0003, 95% confidence interval: 0.9998-1.0008, P = 0.20). A null association was also observed in other methods. MR-Egger regression and MR-PRESSO respectively showed no evidence of directional (intercept, - 2.25; P = 0.94) and horizontal(P-value in the global heterogeneity test = 0.99) pleiotropic effect across the genetic variants. No substantial evidence was found to support the causal role of AF in the development of PE.

A rat model for acute limb ischemia using microsized gelatin beads

OBJECTIVE

Acute limb ischemia (ALI) is a rapid decrease in lower limb blood flow due to acute occlusion of peripheral arteries or bypass grafts. This study aimed to establish an ALI model using microsized gelatin beads and to investigate the pathophysiological conditions.

METHODS

Male Sprague-Dawley rats were anesthetized, and a low or high dose of microsized gelatin beads was administered into the left femoral artery on days 0 and 7. A control, that is, normal saline (NS) group in which NS was administered in the left femoral artery, a femoral artery cut (FAC) group in which the left femoral artery was cut, and a sciatic nerve cut (SNC) group in which the left sciatic nerve was cut were prepared. After 21 days, the temperature changes and the muscle weights in the lower limbs were measured. To assess nerve damage, the L1-6 sympathetic ganglia were immunostained with activating transcription factor 3 (ATF3) antibody.

RESULTS

In the Low-dose, High-dose, and FAC groups, a decrease in temperature was predominantly observed in the left limb. In the High-dose and SNC groups, the weight of the soleus muscle and extensor digitorum longus in the left limb decreased; however, no weight changes were observed in the Low-dose and FAC groups. Conversely, the weight of the gastrocnemius muscle significantly decreased in the Low-dose, High-dose, FAC, and SNC groups. In the High-dose and SNC groups, the number of ATF3-positive cells in the sympathetic ganglia significantly increased, and in the Low-dose, a small number of ATF3-positive cells were observed. However, ATF3-positive cells were rarely observed in the FAC and NS groups.

CONCLUSION

We established an ALI rat model using microsized gelatin beads. The results of this study suggest that autonomic neuropathy in ALI is related to both muscle damage and peripheral neuropathy.

Association Between Atrial Fibrillation and Diabetes-Related Complications: A Nationwide Cohort Study

OBJECTIVE

This study aimed to investigate the associations between concurrent atrial fibrillation and diabetes-related complications among patients with diabetes.

RESEARCH DESIGN AND METHODS

This nationwide observational cohort study used the health checkup database from the Korean National Health Insurance Service. Patients diagnosed with diabetes who underwent health checkups between 2009 and 2012 were investigated. The patients with atrial fibrillation were matched in a 1:5 ratio with those without atrial fibrillation using propensity scores. Study outcomes included macrovascular, microvascular (diabetic retinopathy and diabetic nephropathy), and diabetic foot complications. The risks of clinical outcomes were measured using hazard ratios (HRs) with 95% CIs.

RESULTS

A total of 65,760 patients with diabetes were analyzed (54,800 without atrial fibrillation and 10,960 with atrial fibrillation). After well-balanced propensity score matching, atrial fibrillation was associated with significantly higher risks of macrovascular complications (HR 1.12, 95% CI 1.09-1.16), diabetic nephropathy (HR 1.23, 95% CI 1.16-1.30), and diabetic foot complications (HR 1.13, 95% CI 1.09-1.17) compared with no atrial fibrillation, while the risk of diabetic retinopathy was comparable (HR 0.99, 95% CI 0.96-1.03). Patients with atrial fibrillation had a significantly higher risk of diabetic foot amputation (HR 4.12, 95% CI 1.98-8.56).

CONCLUSIONS

Among patients with diabetes, concurrent atrial fibrillation was associated with increased risks for diabetes-related macrovascular complications, diabetic nephropathy, and diabetic foot. Such patients require holistic management to reduce the risk of adverse outcomes.

Rivaroxaban plus aspirin vs. dual antiplatelet therapy in endovascular treatment in peripheral artery disease and analysis of medication utilization of different lesioned vascular regions

Background

In the management of Peripheral Arterial Disease (PAD), the administration of anticoagulant or antiplatelet agents is imperative. The use of Dual Antiplatelet Therapy (DAPT) in conjunction with rivaroxaban has shown potential in mitigating adverse outcomes. Given the heterogeneity in the pathology of lower limb arteries, there is a compelling case for individualized treatment strategies.

Methods

In a single-center retrospective study on pharmacotherapy for peripheral artery disease, patients were treated with either aspirin combined with rivaroxaban or aspirin coupled with clopidogrel. The primary efficacy outcome encompassed a composite of increases in the Rutherford classification, acute limb ischemia, amputations due to vascular causes, target lesion revascularization, myocardial infarction, ischemic stroke, and cardiovascular death. The primary safety outcome was major bleeding, as defined by the Thrombolysis in Myocardial Infarction (TIMI) criteria; meanwhile, major bleeding as categorized by the International Society on Thrombosis and Haemostasis (ISTH) served as a secondary safety outcome. The study differentiated between two subgroups: patients with only above-the-knee and below-the-knee arterial lesions.

Results

From January 2016 to December 2021, 455 patients received either clopidogrel plus aspirin or rivaroxaban plus aspirin following endovascular treatment (EVT). The rivaroxaban group (n = 220) exhibited a lower incidence of primary efficacy outcomes [49.1% vs. 60.4%, hazard ratio (HR) 0.77, P = 0.006] but had more TIMI major bleeding events (5.9% vs. 2.1%, HR 2.6, P = 0.04). ISTH major bleeding events did not show a significant difference, though a higher percentage of rivaroxaban patients discontinued medication due to bleeding (10% vs. 4.7%, HR 2.2, P = 0.03). In the above-the-knee arterial disease subgroup, the rivaroxaban group demonstrated a lower incidence of primary efficacy outcomes (28.2% vs. 45.2%, HR 0.55, P = 0.02). In the below-the-knee arterial disease subgroup, no significant difference was observed in the occurrence of primary efficacy events between the two groups (58.7% vs. 64.8%, HR 0.76, P = 0.14).

Conclusion

Rivaroxaban plus aspirin improved outcomes compared to DAPT in patients with lower extremity artery disease. Similar findings were observed in the above-the-knee artery lesion-only group. However, in the below-the-knee artery lesion-only group, rivaroxaban plus aspirin did not surpass DAPT in efficacy. Regarding safety, rivaroxaban plus aspirin exhibited higher bleeding risks and more frequent treatment discontinuation than aspirin combined with clopidogrel.

Global burden of peripheral artery disease and its risk factors, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019

BACKGROUND

Peripheral artery disease is a growing public health problem. We aimed to estimate the global disease burden of peripheral artery disease, its risk factors, and temporospatial trends to inform policy and public measures.

METHODS

Data on peripheral artery disease were modelled using the Global Burden of Disease, Injuries, and Risk Factors Study (GBD) 2019 database. Prevalence, disability-adjusted life years (DALYs), and mortality estimates of peripheral artery disease were extracted from GBD 2019. Total DALYs and age-standardised DALY rate of peripheral artery disease attributed to modifiable risk factors were also assessed.

FINDINGS

In 2019, the number of people aged 40 years and older with peripheral artery disease was 113 million (95% uncertainty interval [UI] 99·2-128·4), with a global prevalence of 1·52% (95% UI 1·33-1·72), of which 42·6% was in countries with low to middle Socio-demographic Index (SDI). The global prevalence of peripheral artery disease was higher in older people, (14·91% [12·41-17·87] in those aged 80-84 years), and was generally higher in females than in males. Globally, the total number of DALYs attributable to modifiable risk factors in 2019 accounted for 69·4% (64·2-74·3) of total peripheral artery disease DALYs. The prevalence of peripheral artery disease was highest in countries with high SDI and lowest in countries with low SDI, whereas DALY and mortality rates showed U-shaped curves, with the highest burden in the high and low SDI quintiles.

INTERPRETATION

The total number of people with peripheral artery disease has increased globally from 1990 to 2019. Despite the lower prevalence of peripheral artery disease in males and low-income countries, these groups showed similar DALY rates to females and higher-income countries, highlighting disproportionate burden in these groups. Modifiable risk factors were responsible for around 70% of the global peripheral artery disease burden. Public measures could mitigate the burden of peripheral artery disease by modifying risk factors.

FUNDING

Bill & Melinda Gates Foundation.

Incidence and Predictors of Acute Limb Ischemia in Patients With Acute Myocardial Infarction-Insight from National Readmission Database

Acute limb ischemia (ALI) has been a rare complication of acute myocardial infarction (AMI), however, with the increasing use of mechanical circulatory devices it is seen more frequently. The incidence and predictors of ALI in patients with AMI in contemporary clinical practice are unknown. A retrospective review of patients with index hospitalization for AMI in the Nationwide Readmission Database from 2016 to 2019 was done. We evaluated the annual incidence of ALI and its impact on outcomes. We used multivariate logistic regression analysis to determine predictors of ALI. In 1,283,586 patients with AMI, 3,971 patients (0.31%) had ALI and 365 (0.03%) had limb amputation. The 3 major predictors of ALI were peripheral artery disease (odds ratio [OR] 11.91, 95% confidence interval [CI]: 10.78 to 13.51), intravascular microaxial left ventricular assist device (OR 4.39, 95% CI 3.86 to 5.00), and veno-arterial extracorporeal membrane oxygenation (OR 4.37, 95% CI 3.19 to 6.01). Intra-aortic balloon pump had a substantially lower predictive ability (OR 1.81, 95% CI 1.63 to 2.0, p <0.0001) than other forms of mechanical circulatory support. The mortality rate in patients with ALI was significantly higher than those without ALI (19.49% vs 4.85%, p <0.0001). Patients who developed ALI had higher rates of amputation (1.59% vs 0.02%, p <0.0001). This observational nationwide study showed that ALI is an important complication in patients with AMI and is more frequently seen in patients who have peripheral artery disease, and require a left ventricular assist device or venoarterial extracorporeal membrane oxygenation. This complication was also associated with significantly higher in-hospital mortality.

Updates and Advances in Cardiovascular Nursing: Peripheral Arterial Disease

This article focuses on peripheral arterial disease (PAD) of the lower extremities. There is a higher incidence of myocardial infarction, stroke, and cardiovascular death, resulting in higher rates of all-cause mortality compared with patients without PAD. Thus, the presence of PAD is a marker for systemic atherosclerotic disease and can lead to the early detection and treatment of coronary artery disease or cerebrovascular disease. This article reviews the latest information about the prevalence, symptoms, classification, diagnosis, and treatment of PAD. Monitoring and detection of PAD are also discussed, including implications for nursing care.

Focus on the Prevention of Acute Limb Ischemia: Centrality of the General Practitioner from the Point of View of the Internist

The thrombotic mechanism, being common to peripheral arterial disease (PAD), acute myocardial infarction (AMI), and stroke, is responsible for the highest number of deaths in the western world. However, while much has been done for the prevention, early diagnosis, therapy of AMI and stroke, the same cannot be said for PAD, which is a negative prognostic indicator for cardiovascular death. Acute limb ischemia (ALI) and chronic limb ischemia (CLI) are the most severe manifestations of PAD. They both are defined by the presence of PAD, rest pain, gangrene, or ulceration and we consider ALI if symptoms last less than 2 weeks and CLI if they last more than 2 weeks. The most frequent causes are certainly atherosclerotic and embolic mechanisms and, to a lesser extent, traumatic or surgical mechanisms. From a pathophysiological point of view, atherosclerotic, thromboembolic, inflammatory mechanisms are implicated. ALI is a medical emergency that puts both limb and the patient's life at risk. In patients over age 80 undergoing surgery, mortality remains high reaching approximately 40% as well as amputation approximately 11%. The purpose of this paper is to summarize the scientific evidence on the possibilities of primary and secondary prevention of ALI and to raise awareness among doctors involved in the management of ALI, in particular by describing the central role of the general practitioner.

[Acute limb ischemia - what is new?]

Acute limb ischemia is a vascular emergency and current guidelines emphasize the need for rapid treatment in a vascular center with an option of open surgical and interventional revascularization. Endovascular revascularization options for acute limb ischemia are increasingly focused on a wide range of mechanical thrombectomy devices based on different operating principles.For patients with acute limb ischemia in the setting of covid-19 infection high mortality rates and low technical success rates of revascularization procedures have been described.

Incidence and predictors of acute limb ischemia in acute myocardial infarction complicated by cardiogenic shock

OBJECTIVE

To describe the incidence and predictors of acute limb ischemia (ALI) in patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS).

METHODS

Patients with index hospitalizations for AMI complicated by cardiogenic shock from 2016 to 2019 in the US National Readmission Database were identified. We evaluated the incidence of ALI and its associated mortality, length of stay, and cost of hospitalization. We used multivariable logistic regression to determine independent predictors of ALI in this population.

RESULTS

A total of 84,615 patients had AMI complicated by cardiogenic shock and 1302 (1.54%) developed ALI. The rates of ALI increased from 1.29% in 2016 to 1.66% in 2019 (P ≤ .002). The use of microaxial mechanical circulatory support increased from 2.25% in 2016 to 13.36% in 2019 (P = .0001). The major predictors of ALI included peripheral arterial disease (odds ratio [OR], 7.34; 95% confidence interval [CI], 6.12-8.81), venoarterial extracorporeal membrane oxygenation (OR, 4.40; 95% CI, 3.19-6.07), and microaxial mechanical circulatory support (OR, 3.12; 95% CI, 2.74-3.55). ALI in patients with cardiogenic shock was associated higher mortality (39.20% vs 33.53%; P ≤ .0001).

CONCLUSIONS

This nationwide observational study shows that ALI is an important complication of AMI with cardiogenic shock. This complication is associated with higher mortality. In addition to peripheral artery disease, the use of mechanical circulatory devices was associated with significantly higher rates of ALI.

Clinical Characteristics and Predictors of Long-Term Prognosis of Acute Peripheral Arterial Ischemia Patients Treated Surgically

BACKGROUND

Acute peripheral arterial ischemia is a rapidly developing loss of perfusion, resulting in ischemic clinical manifestations. This study aimed to assess the incidence of cardiovascular mortality in patients with acute peripheral arterial ischemia and either atrial fibrillation (AF) or sinus rhythm (SR).

METHODS

This observational study involved patients with acute peripheral ischemia treated surgically. Patients were followed-up to assess cardiovascular mortality and its predictors.

RESULTS

The study group included 200 patients with acute peripheral arterial ischemia and either AF (n = 67) or SR (n = 133). No cardiovascular mortality differences between the AF and SR groups were observed. AF patients who died of cardiovascular causes had a higher prevalence of peripheral arterial disease (58.3% vs. 31.6%, p = 0.048) and hypercholesterolemia (31.2% vs. 5.3%, p = 0.028) than those who did not die of such causes. Patients with SR who died of cardiovascular causes more frequently had a GFR <60 mL/min/1.73 m² (47.8% vs. 25.0%, p = 0.03) and were older than those with SR who did not die of such causes. The multivariable analysis shows that hyperlipidemia reduced the risk of cardiovascular mortality in patients with AF, whereas in patients with SR, an age of ≥75 years was the predisposing factor for such mortality.

CONCLUSIONS

Cardiovascular mortality of patients with acute ischemia did not differ between patients with AF and SR. Hyperlipidemia reduced the risk of cardiovascular mortality in patients with AF, whereas in patients with SR, an age of ≥75 years was a predisposing factor for such mortality.

Bioengineering for vascularization: Trends and directions of photocrosslinkable gelatin methacrylate hydrogels

Gelatin methacrylate (GelMA) hydrogels have been widely used in various biomedical applications, especially in tissue engineering and regenerative medicine, for their excellent biocompatibility and biodegradability. GelMA crosslinks to form a hydrogel when exposed to light irradiation in the presence of photoinitiators. The mechanical characteristics of GelMA hydrogels are highly tunable by changing the crosslinking conditions, including the GelMA polymer concentration, degree of methacrylation, light wavelength and intensity, and light exposure time et al. In this regard, GelMA hydrogels can be adjusted to closely resemble the native extracellular matrix (ECM) properties for the specific functions of target tissues. Therefore, this review focuses on the applications of GelMA hydrogels for bioengineering human vascular networks in vitro and in vivo. Since most tissues require vasculature to provide nutrients and oxygen to individual cells, timely vascularization is critical to the success of tissue- and cell-based therapies. Recent research has demonstrated the robust formation of human vascular networks by embedding human vascular endothelial cells and perivascular mesenchymal cells in GelMA hydrogels. Vascular cell-laden GelMA hydrogels can be microfabricated using different methodologies and integrated with microfluidic devices to generate a vasculature-on-a-chip system for disease modeling or drug screening. Bioengineered vascular networks can also serve as build-in vasculature to ensure the adequate oxygenation of thick tissue-engineered constructs. Meanwhile, several reports used GelMA hydrogels as implantable materials to deliver therapeutic cells aiming to rebuild the vasculature in ischemic wounds for repairing tissue injuries. Here, we intend to reveal present work trends and provide new insights into the development of clinically relevant applications based on vascularized GelMA hydrogels.

pH/Thermosensitive dual-responsive hydrogel based sequential delivery for site-specific acute limb ischemia treatment

Acute limb ischemia (ALI) is the most severe manifestation of peripheral artery disease, accompanied by pH/temperature-microenvironment changes in two different phases. In the acute phase, temperature and pH are significantly decreased, and reactive oxygen species (ROS) are excessively generated owing to the sharp reduction of blood perfusion. Afterwards, in the chronic phase, although the temperature gradually recovers, angiogenesis is delayed due to chronic vascular injury, skeletal muscle cell apoptosis and endothelial cell dysfunction. Current therapeutic strategies mainly focus on recanalization; however, their effects on scavenging ROS in the acute phase and promoting angiogenesis in the chronic phase are quite limited. Herein, an injectable pH and temperature dual-responsive poloxamer 407 (PF127)/hydroxymethyl cellulose (HPMC)/sodium alginate (SA)-derived hydrogel (FHSgel), encapsulating melatonin and diallyl trisulfide-loaded biodegradable hollow mesoporous silica nanoparticles (DATS@dHMSNs), is developed, which can intelligently respond to the different phases of ALI. In the acute phase of ischemia, the decreased pH results in the rapid release of melatonin to scavenge excessive ischemia-induced ROS. On the other hand, in the chronic repair phase, the recovered temperature triggers the sustained release of DATS@dHMSNs from the FHSgel, thus generating hydrogen sulfide (H₂S) to enhance the angiogenesis and microcirculation reconstruction of ischemic limbs.

Molecular Circuit Discovery for Mechanobiology of Cardiovascular Disease

Purpose

Cardiovascular diseases, the world’s leading cause of death, are linked to changes in tissue mechanical and material properties that affect the signaling of cells in the damaged tissue. It is hard to predict the effect of altered physical cues on cell signaling though, due to the large number of molecules potentially involved. Our goal is to identify genes and molecular networks that mediate cellular response to cardiovascular disease and cardiovascular-related forces.

Methods

We used custom computer code, statistics, and bioinformatics tools to meta-analyze PubMed-indexed citations for mentions of genes and proteins.

Results

We identified the names and frequencies of genes studied in the context of mechanical cues (shear, strain, stiffness, and pressure) and major diseases (stroke, myocardial infarction, peripheral arterial disease, deep vein thrombosis). Using statistical and bioinformatics analyses of these biomolecules, we identified the cellular functions and molecular gene sets linked to cardiovascular diseases, biophysical cues, and the overlap between these topics. These gene sets formed independent molecular circuits that each related to different biological processes, including inflammation and extracellular matrix remodeling.

Conclusion

Computational analysis of cardiovascular and mechanobiology publication data can be used for discovery of evidence-based, data-rich gene networks suitable for future systems biology modeling of mechanosignaling.

Statins and statin intensity in peripheral artery disease

Background: Peripheral artery disease (PAD) affects more than 202 million people worldwide. Several studies have shown that patients with PAD are often undertreated, and that statin utilization is suboptimal. European and American guidelines highlight statins as the first-line lipid-lowering therapy to treat patients with PAD. Our objective with this meta-analysis was to further explore the impact of statins on lower extremities PAD endpoints and examine whether statin dose (high vs. low intensity) impacts outcomes. Patients and methods: We performed a systematic review and meta-analysis according to the PRISMA guidelines. Any study that presented a comparison of use of statins vs. no statins for PAD patients or studies comparing high vs. low intensity statins were considered to be potentially eligible. We excluded studies with only critical limb threatening ischemia (CLTI) patients. The Medline (PubMed) database was searched up to January 31, 2021. A random effects meta-analysis was performed. Results: In total, 39 studies and 275,670 patients were included in this meta-analysis. In total, 136,025 (49.34%) patients were on statins vs. 139,645 (50.66%) who were not on statins. Statin use was associated with a reduction in all cause-mortality by 42% (HR: 0.58, 95% CI: 0.49-0.67, p<0.01) and cardiovascular death by 43% (HR: 0.57, 95% CI: 0.40-0.74, p<0.01). Statin use was associated with an increase in amputation-free survival by 56% (HR: 0.44, 95% CI: 0.30-0.58, p<0.01). The risk of amputation and loss of patency were reduced by 35% (HR: 0.65, 95% CI: 0.41-0.89, p<0.01) and 46% (HR: 0.54, 95% CI: 0.34-0.74, p<0.01), respectively. Statin use was also associated with a reduction in the risk of major adverse cardiovascular events (MACE) by 35% (HR: 0.65, 95% CI: 0.51-0.80, p<0.01) and myocardial infarction rates by 41% (HR: 0.59, 95% CI: 0.33-0.86, p<0.01). Among patients treated with statins, the high-intensity treatment group was associated with a reduction in all cause-mortality by 36% (HR: 0.64, 95% CI: 0.54-0.74, p<0.01) compared to patients treated with low intensity statins. Conclusions: Statin treatment among patients with PAD was associated with a statistically significant reduction in all-cause mortality, cardiovascular mortality, MACE, risk for amputation, or loss of patency. Higher statin dose seems to be associated with improved 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.

Rivaroxaban and Risk of Venous Thromboembolism in Patients With Symptomatic Peripheral Artery Disease After Lower Extremity Revascularization

IMPORTANCE

Prior studies have observed an association between the burden of atherosclerotic vascular disease and the risk of venous thromboembolism (VTE). The association is not well described in peripheral artery disease (PAD) after lower extremity revascularization (LER).

OBJECTIVE

To describe the risk of, factors associated with, and outcomes after VTE, as well as the association of low-dose rivaroxaban plus antiplatelet therapy with VTE after LER.

DESIGN, SETTING, AND PARTICIPANTS

This global, multicenter cohort study used data from the Vascular Outcomes Study of ASA (acetylsalicylic acid) Along With Rivaroxaban in Endovascular or Surgical Limb Revascularization for PAD (VOYAGER PAD) randomized clinical trial, which enrolled patients from 2015 to 2018 with median follow-up of 28 months. Participants included patients with PAD undergoing LER. Patients with an indication for therapeutic anticoagulation were excluded. Data were analyzed from September 2020 to September 2021.

EXPOSURE

Randomization to rivaroxaban 2.5 mg twice daily or placebo on a background of aspirin 100 mg daily; short-term clopidogrel was used at the discretion of the treating physician.

MAIN OUTCOMES AND MEASURES

Symptomatic VTE was a prespecified secondary outcome and prospectively collected.

RESULTS

Among 6564 patients (median [IQR] age, 67 [61-73] years; 4860 [74.0%] men), 66 patients had at least 1 VTE. The 3-year rate of VTE in patients receiving placebo was 1.7%, and the pattern of risk was linear (year 1: 0.5%; year 2: 1.1%). After multivariable modeling, weight (hazard ratio [HR], 3.04; 95% CI, 1.09-8.43), hypertension (HR, 2.11; 95% CI, 0.91-4.89), prior amputation (HR, 2.07; 95% CI, 0.95-4.53), and older age (HR, 1.81; 95% CI, 1.06-3.11) were associated with increased risk of VTE. VTE was associated with risk of subsequent mortality (HR, 7.22; 95% CI, 4.66-11.19). Compared with aspirin alone, rivaroxaban plus aspirin was associated with lower VTE risk (HR, 0.61; 95% CI, 0.37-0.998; P = .047), with benefit apparent early and sustained over time. This association was not modified by use of clopidogrel at randomization (without clopidogrel: HR, 0.55; 95% CI, 0.29-1.07; with clopidogrel: HR, 0.69; 95% CI, 0.32-1.48; P for interaction = .67).

CONCLUSIONS AND RELEVANCE

In this cohort study, there was continuous risk for VTE after LER in patients with PAD, with greater risk in patients who were older and had obesity and those with more severe PAD, as reflected by prior amputation. Low-dose rivaroxaban plus aspirin was associated with lower VTE risk compared with aspirin alone, with benefits apparent early and continued over time. The spectrum of venous and arterial thrombotic events and overall benefits of more potent antithrombotic strategies for prevention should be considered after LER for PAD.

The Mysterious Risk of Arterial Thrombosis With COVID-19: A Case Series and Systematic Review of Acute Limb Ischaemia

Introduction: Coronavirus disease 2019 (COVID-19) generates a cytokine storm that predisposes patients to systemic complications including arterial thrombosis (AT) and acute limb ischaemia (ALI). This study reviews our understanding of the incidence and outcomes of patients with COVID-19 who develop AT.

Methods: The case notes of all emergency patients with COVID-19 referred to the vascular services between March 2020 and March 2021 were reviewed. The study was undertaken to measure 30-day outcomes. Additionally, a literature search was undertaken according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using the following search terms: acute limb ischaemia OR arterial thrombosis OR thrombectomy OR embolectomy AND COVID-19.

Results: During March 2020 and March 2021, 60,000 people tested positive for COVID-19 in Norfolk. A total of 33 patients were referred to the vascular services, of which 15 had AT (estimated incidence of 0.03%). Of AT patients, 93% had ALI. Fourteen locations of AT were identified. Of ATs, 36% were infrainguinal. The 30-day mortality was 60%. Three patients underwent surgery: two embolectomies (one requiring subsequent below-knee amputation (BKA) and the other died) and one primary BKA requiring subsequent above-knee amputation. The 30-day amputation-free survival (AFS) rate was 29%. The literature search identified 361 studies prior to a thorough full-text review. Nine case series were included with more than 10 participants each. The incidence of AT was reported as high as 15%. In-hospital mortality was 40%, with a significant proportion undergoing amputation or palliative care. Approximately a third of patients undergoing revascularisation subsequently re-occluded. AFS remained as low as 25%.

Conclusion: The incidence of AT within the vascular surgery territory in COVID-19 patients is low; however, it is associated with poor 30-day AFS. A computed tomography angiography protocol including the entire major vessels may be indicated in COVID-19 patients.

The Impact of Atrial Fibrillation on Outcomes of Peripheral Arterial Disease: Analysis of Routinely Collected Primary Care Data

BACKGROUND

The combination of peripheral arterial disease and atrial fibrillation is linked with high risk of mortality and stroke. This study aims to investigate the impact of atrial fibrillation on patients with diagnosed peripheral arterial disease.

METHODS

This is a retrospective study using The Health Improvement Network database, which contains prospectively collected data from participating primary care practices. Patients with a new diagnosis of peripheral arterial disease between January 8, 1995 and January 5, 2017 were identified in the database alongside relevant demographic information, clinical history, and medications. Every patient in the dataset with peripheral arterial disease and baseline atrial fibrillation (case) was matched to a patient without atrial fibrillation (control) with similar characteristics using propensity score matching. Cox-regression analysis was performed and hazard ratios (HR) calculated for the outcomes of death, stroke, ischemic heart disease, heart failure, and major amputation.

RESULTS

Prevalence of atrial fibrillation in this cohort was 10.2%. All patients with peripheral arterial disease and atrial fibrillation (n = 5685) were matched with 5685 patients without atrial fibrillation but otherwise similar characteristics. After multivariate analysis, atrial fibrillation was independently associated with mortality (HR 1.18; 95% confidence interval [CI], 1.12-1.26; P < .01), cerebrovascular events (HR 1.35; 95% CI, 1.17-1.57; P < .01), and heart failure (HR 1.87; 95% CI, 1.62-2.15; P < .01), but not with ischemic heart disease or limb loss.

CONCLUSION

In peripheral arterial disease patients, atrial fibrillation is a risk factor for mortality, stroke, and heart failure. This emphasizes the need for proactive surveillance and holistic management of these patients.

The Impact of Atrial Fibrillation on One-Year Mortality in Patients with Severe Lower Extremity Arterial Disease

Atrial fibrillation (Afib) is associated with the presence of lower extremity arterial disease (LEAD), but its effect on a severe LEAD prognosis remains unclear. We investigated the association between Afib and clinical outcomes. We retrospectively enrolled consecutive severe LEAD patients undergoing percutaneous transluminal angioplasty between 1 January 2013 and 31 December 2018. Patients were divided according to the history of any type of Afib and followed for at least one year. The primary outcome was all-cause mortality. Secondary outcomes were cardiac-related mortality and major adverse cardiovascular events (MACEs). The study included 222 patients aged 74 ± 11 years (54% male), and 12.6% had acute limb ischemia. The Afib group had significantly higher rates of all-cause mortality (42.9% vs. 20.1%, p = 0.014) and MACEs (32.1% vs. 14.4%, p = 0.028) than the non-Afib group. Afib was independently associated with all-cause mortality (adjusted HR: 2.153, 95% CI: 1.084–4.276, p = 0.029) and MACEs (adjusted HR: 2.338, 95% CI: 1.054–2.188, p = 0.037). The other factors associated with all-cause mortality included acute limb ischemia (adjusted HR: 2.898, 95% CI: 1.504–5.586, p = 0.001), Rutherford classification, and heart rate. Afib was significantly associated with increased risks of one-year all-cause mortality and MACEs in patients with severe LEAD. Future studies should investigate whether oral anticoagulants benefit these patients.

Antiplatelet agents for chronic kidney disease

BACKGROUND

Antiplatelet agents are widely used to prevent cardiovascular events. The risks and benefits of antiplatelet agents may be different in people with chronic kidney disease (CKD) for whom occlusive atherosclerotic events are less prevalent, and bleeding hazards might be increased. This is an update of a review first published in 2013.

OBJECTIVES

To evaluate the benefits and harms of antiplatelet agents in people with any form of CKD, including those with CKD not receiving renal replacement therapy, patients receiving any form of dialysis, and kidney transplant recipients.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 13 July 2021 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We selected randomised controlled trials of any antiplatelet agents versus placebo or no treatment, or direct head-to-head antiplatelet agent studies in people with CKD. Studies were included if they enrolled participants with CKD, or included people in broader at-risk populations in which data for subgroups with CKD could be disaggregated.

DATA COLLECTION AND ANALYSIS

Four authors independently extracted data from primary study reports and any available supplementary information for study population, interventions, outcomes, and risks of bias. Risk ratios (RR) and 95% confidence intervals (CI) were calculated from numbers of events and numbers of participants at risk which were extracted from each included study. The reported RRs were extracted where crude event rates were not provided. Data were pooled using the random-effects model. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We included 113 studies, enrolling 51,959 participants; 90 studies (40,597 CKD participants) compared an antiplatelet agent with placebo or no treatment, and 29 studies (11,805 CKD participants) directly compared one antiplatelet agent with another. Fifty-six new studies were added to this 2021 update. Seven studies originally excluded from the 2013 review were included, although they had a follow-up lower than two months. Random sequence generation and allocation concealment were at low risk of bias in 16 and 22 studies, respectively. Sixty-four studies reported low-risk methods for blinding of participants and investigators; outcome assessment was blinded in 41 studies. Forty-one studies were at low risk of attrition bias, 50 studies were at low risk of selective reporting bias, and 57 studies were at low risk of other potential sources of bias. Compared to placebo or no treatment, antiplatelet agents probably reduces myocardial infarction (18 studies, 15,289 participants: RR 0.88, 95% CI 0.79 to 0.99, I² = 0%; moderate certainty). Antiplatelet agents has uncertain effects on fatal or nonfatal stroke (12 studies, 10.382 participants: RR 1.01, 95% CI 0.64 to 1.59, I² = 37%; very low certainty) and may have little or no effect on death from any cause (35 studies, 18,241 participants: RR 0.94, 95 % CI 0.84 to 1.06, I² = 14%; low certainty). Antiplatelet therapy probably increases major bleeding in people with CKD and those treated with haemodialysis (HD) (29 studies, 16,194 participants: RR 1.35, 95% CI 1.10 to 1.65, I² = 12%; moderate certainty). In addition, antiplatelet therapy may increase minor bleeding in people with CKD and those treated with HD (21 studies, 13,218 participants: RR 1.55, 95% CI 1.27 to 1.90, I² = 58%; low certainty). Antiplatelet treatment may reduce early dialysis vascular access thrombosis (8 studies, 1525 participants) RR 0.52, 95% CI 0.38 to 0.70; low certainty). Antiplatelet agents may reduce doubling of serum creatinine in CKD (3 studies, 217 participants: RR 0.39, 95% CI 0.17 to 0.86, I² = 8%; low certainty). The treatment effects of antiplatelet agents on stroke, cardiovascular death, kidney failure, kidney transplant graft loss, transplant rejection, creatinine clearance, proteinuria, dialysis access failure, loss of primary unassisted patency, failure to attain suitability for dialysis, need of intervention and cardiovascular hospitalisation were uncertain. Limited data were available for direct head-to-head comparisons of antiplatelet drugs, including prasugrel, ticagrelor, different doses of clopidogrel, abciximab, defibrotide, sarpogrelate and beraprost.

AUTHORS' CONCLUSIONS

Antiplatelet agents probably reduced myocardial infarction and increased major bleeding, but do not appear to reduce all-cause and cardiovascular death among people with CKD and those treated with dialysis. The treatment effects of antiplatelet agents compared with each other are uncertain.

Tungsten disulfide nanotubes enhance flow-induced crystallization and radio-opacity of polylactide without adversely affecting in vitro toxicity

Treatment of vascular disease, from peripheral ischemia to coronary heart disease (CHD), is poised for transformation with the introduction of transient implants designed to "scaffold" regeneration of blood vessels and ultimately leave nothing behind. Improved materials could expand the use of these devices. Here, we examine one of the leading polymers for bioresorbable scaffolds (BRS), polylactide (PLA), as the matrix of nanocomposites with tungsten disulfide (WS₂) nanotubes (WSNT), which may provide mechanical reinforcement and enhance radio-opacity. We evaluate in vitro cytotoxicity using vascular cells, flow-induced crystallization and radio-opacity of PLA-WSNT nanocomposites at low WSNT concentration. A small amount of WSNT (0.1 wt%) can effectively promote oriented crystallization of PLA without compromising molecular weight. And radio-opacity improves significantly: as little as 0.5 to 1 wt% WSNT doubles the radio-opacity of PLA-WSNT relative to PLA at 17 keV. The results suggest that a single component, WSNT, has the potential to increase the strength of BRS to enable thinner devices and increase radio-opacity to improve intraoperative visualization. The in vitro toxicity results indicate that PLA-WSNT nanocomposites are worthy of investigation in vivo. Although substantial further preclinical studies are needed, PLA-WSNT nanocomposites may provide a complement of material properties that may improve BRS and expand the range of lesions that can be treated using transient implants. STATEMENT OF SIGNIFICANCE: Bioresorbable Scaffolds (BRSs) support regeneration of arteries without permanent mechanical constraint. Poly-L-lactide (PLLA) is the structural material of the first approved BRS for coronary heart disease (ABSORB BVS), withdrawn due to adverse events in years 1-3. Here, we examine tungsten disulfide (WS₂) nanotubes (WSNT) in PLA to address two contributors to early complications: (1) reinforce PLLA (enable thinner BRS), and (2) increase radiopacity (provide intraoperative visibility). For BRS, it is significant that WSNT disperse, remain dispersed, reduce friction and improve mechanical properties without additional chemicals or surface modifications. Like WS₂ nanospheres, bare WSNT and PLA-WSNT nanocomposites show low cytotoxicity in vitro. PLA-WSNT show enhanced flow-induced crystallization relative to PLA, motivating future study of the processing behavior and strength of these materials.

Mechanical revascularization using Solitaire AB device for acute limb ischemia secondary to popliteal and infrapopliteal embolic occlusion

Objective

Acute limb ischemia is one of the most common arterial emergencies. The data of mechanical revascularization using Solitaire AB device coupled with thromboaspiration for the treatment of popliteal and infrapopliteal acute limb ischemia are limited. The aim of this study was to review the preliminary safety and effectiveness.

Methods

We performed a single-center retrospective review of patients with popliteal and infrapopliteal acute limb ischemia treated with Solitaire AB device coupled with thromboaspiration from February 2019 to May 2020. Adjunctive balloon angioplasty was performed to correct coexisting atherosclerotic stenosis. Technical success was defined as successful deployment of the Solitaire AB device across the occlusive segment and successful retrieval without the use of adjunctive catheter-directed thrombolysis or balloon angioplasty. Clinical success was defined as the relief of symptoms related to acute limb ischemia. Follow-up outcomes were also reviewed.

Results

There were 15 consecutive patients who underwent 16 Solitaire AB devices. Technical success was achieved in 11 (73.3%) patients. Of the unsuccessful patients, double-stent retrievers were employed in 1 (6.7%) patient. Two patients who encountered residual clots in distal small arteries underwent adjunctive catheter-directed thrombolysis. An adjunctive balloon angioplasty was required in 1 (6.7%) patient. All patients had notable acute limb ischemia symptom relief after the procedures. Clinical success was achieved in 14 (93.3%) patients. Besides one patient encountered minor amputation, the major amputation was prevented in all patients. No device-related complications or distal embolization events were recorded during the procedures. At the follow-up of 12 months, all surviving patients remained symptom-free, the patency was achieved in 12 (80%) patients and the limb salvage was 100%.

Conclusions

Preliminary outcomes suggest that mechanical revascularization using Solitaire AB device coupled with manual thromboaspiration appears to be a rapid, safe, and effective modality that appears to reduce the requirement for catheter-directed thrombolysis.

Advances in knowledge

These findings may add a promising recanalization therapy for acute embolic occlusion of the acute limb ischemia secondary to popliteal and infrapopliteal arteries.

Medical Therapy Following Urgent/Emergent Revascularization in Peripheral Artery Disease Patients (Canadian Acute Limb Ischemia Registry [CANALISE I])

Background

Following severe limb ischemia requiring urgent/emergent revascularization, peripheral arterial disease patients suffer a high risk of recurrent atherothrombosis.

Methods

Patients discharged from Hamilton General Hospital (Hamilton, Ontario) between April 2016 and September 2017 following severe limb ischemia requiring urgent/emergent revascularization were identified via the Local Health Integration Network CorHealth database, with supplemental information from chart review.

Results

A total of 158 patients admitted for urgent/emergent revascularization were identified (148 alive at discharge). Among patients without a pre-existing indication for anticoagulation, 38.8% (n = 47) were discharged on single-antiplatelet therapy, 27.3% (n = 33) on dual-antiplatelet therapy, 19.8% (n = 24) on anticoagulants plus antiplatelet therapy, 6.6% (n = 8) on anticoagulants alone, and 2.6% (n = 3) on unknown therapy. Patients who received angioplasty with stenting were more likely be discharged on dual-antiplatelet therapy (hazard ratio [HR]: 7.14; 95% confidence interval [CI]: 2.87-17.76; P < 0.01); patients who received an embolectomy/thrombectomy were more likely be discharged on an anticoagulant alone (HR: 2.61; 95% CI: 1.00-6.81; P = 0.049); and patients who received peripheral bypass grafting were more likely be discharged on single-antiplatelet therapy (HR: 2.28; 95% CI: 1.11-4.69; P = 0.024). Neither statins (60.8% vs 56.3%; P = 0.23) nor renin–angiotensin–aldosterone system inhibitors (48.7% vs 50.6%; P = 0.58) were prescribed at higher rates at discharge, compared with the rate at admission.

Conclusions

Substantial heterogeneity exists in antithrombotic prescription following urgent/emergent revascularization. No intensification of non-antithrombotic vascular protective medications occurred during hospitalization. Clinical trials and health system interventions to optimize medical therapy in peripheral arterial disease patients are urgently needed.

Endovascular revascularization strategies using catheter-based thrombectomy versus conventional catheter-directed thrombolysis for acute limb ischemia

Background

Acute limb ischemia (ALI) is an important clinical event threatening both life and the affected limbs, but the optimal treatment for ALI remains undefined. The aim of this study was to compare the safety and effectiveness of thrombectomy approaches via either catheter-based thrombectomy (CBT) or catheter-directed thrombolysis (CDT).

Methods

A total of 98 patients (mean age 69.7 years, 60 male) who underwent endovascular intervention for ALI from January 2015 to July 2019 were included. Of these, 57 were treated with primary CBT via a large-bore catheter, an AngioJet catheter or Rotarex catheter, and/or underwent low-dose CDT, and 41 were treated with primary CDT. The safety and effectiveness of CBT compared to conventional CDT and other various endovascular techniques were evaluated.

Results

More Rutherford IIb patients were treated with primary CBT (68.4%) than CDT (26.8%; P < .001). Patients who underwent primary CDT achieved a higher technical success rate than those who underwent primary CBT in a shorter procedure time (P < .001), whereas 42.1% of patients who underwent CBT did not need adjunctive CDT. The duration and dosage of adjunctive CDT in the CBT group were significantly decreased compared with those in the primary CDT group (both P < .001), and the CBT group achieved a shorter in-hospital length of stay (P < .001). Subgroup analysis revealed that patients treated with AngioJet and Rotarex catheters achieved slightly lower dosages, shorter CDT durations and shorter in-hospital stay lengths than those treated with large-bore catheters (P > .05). Clinical success was estimated to be achieved in 98.2% of patients who underwent CBT, which is similar to the 97.6% estimated in those who underwent primary CDT (P = 1.000), and this finding was similar among the CBT subgroups. Patients who underwent CBT had a higher procedure-related distal embolization rate and economic cost than those who underwent primary CDT (P < .05), but it had slightly fewer complications than those who underwent primary CDT (P = .059), especially minor complications (P = .036). The freedom from amputation at 6 and 12 months for CBT and CDT was assessed (93.0% vs 90.2% respectively, P = .625; 89.5% vs 82.9%, respectively, P = .34,). Comparable limb salvage was found for different techniques of large bore catheters, AngioJet catheters and Rotarex catheters. The Kaplan-Meier table analysis also showed similar limb salvage rates between groups.

Conclusions

Endovascular treatment of ALI with the use of catheter-based therapies is an effective modality that can reduce the requirement for thrombolysis, with expected reductions in hemorrhagic complications, but at the risk of remediable distal emboli and increased economic cost. It has a similar clinical outcome to conventional CDT alone. Different CBT techniques have comparable efficacy but different adverse event profiles.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-021-00349-9.

A nationwide cohort investigation on pay-for-performance and major adverse limb events in patients with diabetes

A retrospective cohort study was conducted using claims data from Taiwan's National Health Insurance program to assess the effect of diabetic pay-for-performance (P4P) program on major adverse limb events (MALE) and major adverse cardiovascular events (MACE) in patients with type 2 diabetes mellitus (T2DM). This study included patients with T2DM who had completed or not completed a 1-year P4P program from 2002 to 2013. Propensity-score matching was used to balance the baseline characteristics between groups. The Cox proportional-hazard model and Fine and Gray subdistribution hazard model were used to examine the association between P4P and the risks of MALE, MACE, systemic thromboembolism (ST), heart failure (HF) hospitalization, and all-cause mortality. Patients who underwent the P4P program had a significantly decreased incidence of MALE (2.0% vs. 2.6%, subdistribution hazard ratio [SHR] 0.73, 95% CI 0.71-0.76). Regarding the individual components, the P4P group demonstrated lower risks for foot ulcer (1.1% vs 1.3%, SHR 0.80, 95% CI 0.77-0.84), gangrene (0.57% vs 0.93%, SHR 0.59, 95% CI 0.56-0.63), percutaneous transluminal angioplasty (0.61% vs 0.79%, SHR 0.72, 95% CI 0.68-0.77), and amputation (0.46% vs 0.75%, SHR 0.58, 95% CI 0.55-0.62). In addition, the risks of MACE, ST, HF hospitalization, and all-cause mortality were remarkably lower in the P4P group. The P4P program might significantly reduce critical events of MALE, MACE, ST, HF, and mortality in the diabetic population.

Acute Limb Ischemia in the Young: A Rare Case of Essential Thrombocytosis

Acute limb ischemia (ALI) is rarely observed in young populations. The hypercoagulable state is a notable cause of ALI other than artery disease progression and cardiac embolization. A hypercoagulable state occurs in essential thrombocytosis because of the overproduction of hematopoietic cells secondary to the mutation of the JAK2, CALR, or MPL genes. We report a rare case of a 37-year-old woman presenting with Rutherford IIA ALI in the left lower extremity. Laboratory data revealed she had a platelet count reaching up to 1.38 mil/μL, with other blood profiles being normal. A JAK2 mutation examination was later performed and proved positive. After careful management with catheter-directed thrombolysis, surgical thrombectomy, and cytoreductive therapy using hydroxyurea, the symptoms subsided and eventually restored the patient to physical activity in less than one month.

Principal predictors of major adverse limb events in diabetic peripheral artery disease: A narrative review

Background and aims

The increasing prevalence of diabetes mellitus is causing a massive growth of peripheral artery disease incidences, a disabling complication of diabetic atherosclerosis, which leads often to the amputation of the affected limb. Critical limb ischemia is the terminal disease stage, which requires a prompt intervention to relieve pain and save limbs. However, patients undergoing revascularization often suffer from cardiovascular, cerebrovascular and major adverse limb events with poor outcomes. Furthermore, the same procedure performed in apparently similar patients has various outcomes and lack of an outcome predictive support causes a high lower limb arterial revascularization rate with disastrous effects for patients. We collected the main risk factors of major adverse limb events in a more readable and immediate format of the topic, to propose an overview of parameters to manage effectively peripheral artery disease patients and to propose basics of a new predictive tool to prevent from disabling vascular complications of the disease.

Methods

Most recent and updated literature about the prevalence of major adverse limb events in peripheral artery disease was reviewed to identify possible main predictors.

Results

In this article, we summarized major risk factors of limb revascularization failure and disabling vascular complications collecting those parameters principally responsible for major adverse limb events, which provides physio-pathological explanation of their role in peripheral artery disease.

Conclusion

We evaluated and listed a panel of possible predictors of MALE (Major Adverse Limb Event) in order to contribute to the development of a predictive score, based on a summary of the main risk factors reported in scientific articles, which could improve the management of peripheral artery disease by preventing vascular accidents.

A retrospective analysis of the investigative practices of acute limb ischaemia presenting with an unknown aetiology

BACKGROUND

Acute limb ischaemia (ALI) is a limb and life-threatening condition with significant morbidity. There are currently no consensus recommendations for the investigative practices to determine the aetiology of ALI presenting without a known aetiology. We undertook a detailed analysis of all investigations performed to identify an underlying precipitant in those with unexplained ALI and formulated a suggested diagnostic algorithm for the evaluation of unexplained ALI.

METHODS

ALI cases presenting to a tertiary referral centre over a 3-year period were reviewed, and known aetiologies, and investigations undertaken to determine the underlying aetiology of unexplained ALI were obtained.

RESULTS

Unexplained ALI was found in 27 of 222 patients (12%), of which 21 (78%) had a cause for ALI established after further investigations. Six patients had no cause identified despite extensive work-up. Most patients with unexplained ALI had a cardioembolic source identified as the underlying cause (62%), and this included atrial fibrillation, infective endocarditis, cardiac myxoma and intra-cardiac thrombus. Other causes of unexplained ALI were detected by computed tomography (CT) imaging and included newly diagnosed significant atherosclerotic disease (19%), embolism from isolated proximal large vessel thrombus (10%) and metastatic malignancy (10%). There were no cases attributed to inherited thrombophilias, myeloproliferative neoplasms or anti-phospholipid syndrome.

CONCLUSION

Among patients with unexplained ALI, the majority had a cardioembolic source highlighting the importance of comprehensive cardiac investigations. A subset of patients had alternative causes identified on CT imaging. These data support the use of a collaborative and integrative diagnostic algorithm in the evaluation of unexplained ALI.

Reduction in Acute Limb Ischemia with Rivaroxaban versus Placebo in Peripheral Artery Disease after Lower Extremity Revascularization: Insights from VOYAGER PAD

Background: Patients with peripheral artery disease (PAD) are at heightened risk of acute limb ischemia (ALI), a thrombotic event associated with amputation, disability, and mortality. Prior lower extremity revascularization (LER) is associated with increased ALI risk in chronic PAD. However, the pattern of risk, clinical correlates, and outcomes after ALI early after LER are not well-studied, and effective therapies to reduce ALI post-LER are lacking. Methods: VOYAGER PAD (NCT02504216) randomized patients with PAD undergoing LER to rivaroxaban 2.5 mg twice daily or placebo on a background of low-dose aspirin. The primary outcome was a composite of ALI, major amputation of vascular cause, myocardial infarction, ischemic stroke, or cardiovascular death. ALI was prospectively ascertained and adjudicated by a blinded committee. The cumulative incidence of ALI was calculated using Kaplan Meier estimates, and Cox proportional-hazards models were used to generate hazard ratios and associated confidence intervals. Analyses were performed as intention-to-treat. Results: Among 6,564 patients followed for a median of 2.3 years, 382 (5.8%) had a total of 508 ALI events. In placebo patients, the 3-year cumulative incidence of ALI was 7.8%. After multivariable modeling, prior LER, baseline ABI <0.50, surgical LER, and longer target lesion length were associated with increased risk of ALI. Incident ALI was associated with subsequent all-cause mortality (HR 2.59, 95% CI 1.98-3.39) and major amputation (HR 24.87, 95% CI 18.68-33.12). Rivaroxaban reduced ALI relative to placebo by 33% (absolute risk reduction 2.6% at 3 years, HR 0.67, 95% CI 0.55-0.82, P=0.0001), with benefit starting early (HR 0.45, 95% CI 0.24-0.85, P=0.0068 at 30 days). Benefit was present for severe ALI (associated with death, amputation, or prolonged hospitalization and ICU stay, HR 0.58, 95% CI 0.40-0.83, P=0.003) and regardless of LER type (surgical vs endovascular revascularization, p-interaction=0.42) or clopidogrel use (p-interaction=0.59). Conclusions: After LER for symptomatic PAD, ALI is frequent, particularly early after LER, and is associated with poor prognosis. Low-dose rivaroxaban plus aspirin reduces ALI after LER, including ALI events associated with the most severe outcomes. The benefit of rivaroxaban for ALI appears early, continues over time, and is consistent regardless of revascularization approach or clopidogrel use.

World regional differences in outcomes for patients with peripheral artery disease: Insights from the EUCLID trial

Regional variations exist in the epidemiology of peripheral artery disease (PAD), in comorbidities, use of secondary prevention, and outcomes. Large studies of these variations in worldwide populations are rare. The EUCLID (Examining Use of tiCagreLor In peripheral artery Disease) trial included 13,885 patients with PAD from four geographical regions (Central/South America, Europe, Asia, North America) and compared monotherapy with ticagrelor and clopidogrel. Inclusion criteria were either an ankle-brachial index < 0.80 or a prior revascularization. The primary efficacy endpoint was time to first occurrence of any event in the composite of cardiovascular death, myocardial infarction, or ischemic stroke and did not differ between the study arms. This post hoc analysis of EUCLID confirmed that regional differences occurred in the inclusion criteria with more prior revascularization in North America (73.9%) and Asia (72.5%) compared with Central/South America (34.0%) and Europe (51.6%). The characteristics of patients also differed. Prior amputation at baseline was most frequent in Central/South America (6.3%) compared with other regions (1.6-2.8%). A history of stroke was most common in Asia, coronary heart disease in North America, and diabetes in Central/South America compared with other regions. The incidence of outcomes in patients with PAD varied by region. North America had the highest rate of the primary combined endpoint (5.97 events/100 patient-years). Corresponding rates were 4.80, 3.95, and 3.87 for Asia, Europe, and Central/South America, respectively. Hospitalization for acute limb ischemia (events/100 patient-years) was most frequent in Europe (0.75) and North America (0.74) compared with Asia (0.60) and Central/South America (0.33). Adjustment for inclusion criteria and relevant PAD characteristics did not have a major impact on these regional differences. Further adjustment for concomitant disease, risk factors, and preventive medication modified the regional differences only marginally. In conclusion, substantial regional differences were found in cardiovascular and limb outcomes in patients with PAD and were not explained by variation in the category of included patients, concomitant disease, risk factors, and prevention. Such differences, which may be due to variation in other factors such as background population rates or clinical care, need to be considered when designing and interpreting large international studies (ClinicalTrials.gov Identifier: NCT01732822).

World regional differences in outcomes for patients with peripheral artery disease: Insights from the EUCLID trial

Regional variations exist in the epidemiology of peripheral artery disease (PAD), in comorbidities, use of secondary prevention, and outcomes. Large studies of these variations in worldwide populations are rare. The EUCLID (Examining Use of tiCagreLor In peripheral artery Disease) trial included 13,885 patients with PAD from four geographical regions (Central/South America, Europe, Asia, North America) and compared monotherapy with ticagrelor and clopidogrel. Inclusion criteria were either an ankle–brachial index < 0.80 or a prior revascularization. The primary efficacy endpoint was time to first occurrence of any event in the composite of cardiovascular death, myocardial infarction, or ischemic stroke and did not differ between the study arms. This post hoc analysis of EUCLID confirmed that regional differences occurred in the inclusion criteria with more prior revascularization in North America (73.9%) and Asia (72.5%) compared with Central/South America (34.0%) and Europe (51.6%). The characteristics of patients also differed. Prior amputation at baseline was most frequent in Central/South America (6.3%) compared with other regions (1.6–2.8%). A history of stroke was most common in Asia, coronary heart disease in North America, and diabetes in Central/South America compared with other regions. The incidence of outcomes in patients with PAD varied by region. North America had the highest rate of the primary combined endpoint (5.97 events/100 patient-years). Corresponding rates were 4.80, 3.95, and 3.87 for Asia, Europe, and Central/South America, respectively. Hospitalization for acute limb ischemia (events/100 patient-years) was most frequent in Europe (0.75) and North America (0.74) compared with Asia (0.60) and Central/South America (0.33). Adjustment for inclusion criteria and relevant PAD characteristics did not have a major impact on these regional differences. Further adjustment for concomitant disease, risk factors, and preventive medication modified the regional differences only marginally. In conclusion, substantial regional differences were found in cardiovascular and limb outcomes in patients with PAD and were not explained by variation in the category of included patients, concomitant disease, risk factors, and prevention. Such differences, which may be due to variation in other factors such as background population rates or clinical care, need to be considered when designing and interpreting large international studies (ClinicalTrials.gov Identifier: NCT01732822).

Lower Extremity Peripheral Artery Disease: Contemporary Epidemiology, Management Gaps, and Future Directions: A Scientific Statement From the American Heart Association

Lower extremity peripheral artery disease (PAD) affects >230 million adults worldwide and is associated with increased risk of various adverse clinical outcomes (other cardiovascular diseases such as coronary heart disease and stroke and leg outcomes such as amputation). Despite its prevalence and clinical importance, PAD has been historically underappreciated by health care professionals and patients. This underappreciation seems multifactorial (eg, limited availability of the first-line diagnostic test, the ankle-brachial index, in clinics; incorrect perceptions that a leg vascular disease is not fatal and that the diagnosis of PAD would not necessarily change clinical practice). In the past several years, a body of evidence has indicated that these perceptions are incorrect. Several studies have consistently demonstrated that many patients with PAD are not receiving evidence-based therapies. Thus, this scientific statement provides an update for health care professionals regarding contemporary epidemiology (eg, prevalence, temporal trends, risk factors, and complications) of PAD, the present status of diagnosis (physiological tests and imaging modalities), and the major gaps in the management of PAD (eg, medications, exercise therapy, and revascularization). The statement also lists key gaps in research, clinical practice, and implementation related to PAD. Orchestrated efforts among different parties (eg, health care providers, researchers, expert organizations, and health care organizations) will be needed to increase the awareness and understanding of PAD and improve the diagnostic approaches, management, and prognosis of PAD.

Effect of Rivaroxaban and Aspirin in Patients with Peripheral Artery Disease Undergoing Surgical Revascularization: Insights from the VOYAGER PAD Trial

Background: Patients with peripheral artery disease (PAD) requiring lower extremity revascularization (LER) are at high risk of adverse limb and cardiovascular events. VOYAGER PAD demonstrated that rivaroxaban significantly reduced this risk. The efficacy and safety of rivaroxaban has not been described in patients who underwent surgical LER. Methods: The VOYAGER PAD trial randomized patients with PAD after surgical and endovascular LER to rivaroxaban 2.5mg twice daily plus aspirin or matching placebo plus aspirin and followed for a median of 28 months. The primary endpoint was a composite of acute limb ischemia, major vascular amputation, myocardial infarction, ischemic stroke, or cardiovascular death. The principal safety outcome was Thrombolysis in Myocardial Infarction (TIMI) major bleeding. International Society on Thrombosis and Haemostasis (ISTH) bleeding was a secondary safety outcome. All efficacy and safety outcomes were adjudicated by a blinded independent committee. Results: Of the 6564 randomized, 2185 (33%) underwent surgical LER and 4379 (67%) endovascular. Compared to placebo, rivaroxaban reduced the primary endpoint consistently regardless of LER method (p-interaction 0.43). Following surgical LER, the primary efficacy outcome occurred in 199 (18.4%) patients in the rivaroxaban group and 242 (22.0%) patients in the placebo group with a cumulative incidence at 3 years of 19.7% and 23.9%, respectively (HR 0.81, 95% CI 0.67 - 0.98; p=0.026). In the overall trial, TIMI major bleeding and ISTH major bleeding were increased with rivaroxaban. There was no heterogeneity for TIMI major bleeding (p-interaction 0.17) or ISTH major bleeding (p-interaction 0.73) based on LER approach. Following surgical LER, the principal safety outcome occurred in 11 (1.0%) patients in the rivaroxaban group and 13 (1.2%) patients in the placebo group; 3-year cumulative incidence 1.3% and 1.4% respectively (HR 0.88, 95% CI 0.39-1.95; p=0.75) Among surgical patients, the composite of fatal bleeding or intracranial hemorrhage (p=0.95) and postprocedural bleeding requiring intervention (p=0.93) were not significantly increased. Conclusions: The efficacy of rivaroxaban is associated with a benefit in surgical LER patients. While bleeding was increased with rivaroxaban plus aspirin, the incidence was low, with no significant increase in fatal bleeding, intracranial hemorrhage or postprocedural bleeds requiring intervention. Clinical Trial Registration: URL: https://clinicaltrials.gov Unique Identifier: NCT02504216.

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.

Epidemiology of Peripheral Artery Disease and Polyvascular Disease

Atherosclerotic lower extremity peripheral artery disease (PAD) is increasingly recognized as an important cause of cardiovascular morbidity and mortality that affects >230 million people worldwide. Traditional cardiovascular risk factors, including advanced age, smoking, and diabetes, are strongly linked to an increase risk of PAD. Although PAD has been historically underappreciated compared with coronary artery disease and stroke, greater attention on PAD in recent years has led to important new epidemiological insights in the areas of thrombosis, inflammation, dyslipidemia, and microvascular disease. In addition, the concept of polyvascular disease, or clinically evident atherosclerosis in multiple arterial beds, is increasingly identified as a particularly malignant cardiovascular disease worthy of special clinical attention and further study. It is noteworthy that PAD may increase the risk of adverse outcomes in similar or even greater magnitude than coronary disease or stroke. In this review, we highlight important new advances in the epidemiology of PAD with a particular focus on polyvascular disease, emerging biomarkers, and differential risk pathways for PAD compared with other atherosclerotic diseases.

Lower Extremity Peripheral Artery Disease Without Chronic Limb-Threatening Ischemia: A Review

IMPORTANCE

Lower extremity peripheral artery disease (PAD) affects approximately 8.5 million people in the US and approximately 230 million worldwide.

OBSERVATIONS

Peripheral artery disease is uncommon before aged 50 years but affects up to 20% of people aged 80 years and older. It can be noninvasively diagnosed with the ankle-brachial index (ABI), a ratio of Doppler-recorded pressures in the dorsalis pedis and/or posterior tibial artery in each leg to brachial artery pressures. An ABI value less than 0.90 is 57% to 79% sensitive and 83% to 99% specific for arterial stenosis of at least 50%. Intermittent claudication, consisting of exertional calf pain that does not begin at rest and that resolves within 10 minutes of rest, is considered the classic symptom of PAD. However, 70% to 90% of people with an ABI value less than 0.90 either report no exertional leg symptoms (ie, asymptomatic) or report leg symptoms with walking that are not consistent with classic claudication. Over time, people with PAD restrict walking activity or slow walking speed to avoid leg symptoms. Thus, although approximately 75% of people with PAD report no change in leg symptoms over time, those with PAD have significantly greater annual declines in 6-minute walk performance compared with those without it. Approximately 11% of people with PAD develop chronic limb-threatening ischemia, the most severe form of PAD. Compared with people without PAD, those with the disease have approximately twice the rate of all-cause mortality, cardiovascular mortality, and major coronary events at 10-year follow-up. High-dose statins and antiplatelet therapy with or without antithrombotic therapy reduced rates of coronary events and stroke in people with PAD. Supervised treadmill exercise improved 6-minute walk distance by 30 to 35 m, consistent with a clinically meaningful change, whereas effective home-based walking exercise interventions improved 6-minute walk by 42 to 53 m. Effective home-based exercise programs require behavioral methods, including monitoring by a coach.

CONCLUSIONS AND RELEVANCE

Peripheral artery disease affects approximately 230 million people worldwide and is associated with increased rates of cardiovascular events, lower extremity events, and functional decline compared with that of people without PAD. People with PAD should be treated with the highest dose of statin tolerated, antithrombotic and/or antiplatelet therapy, and exercise.

A systematic review and meta-analysis of outcomes after acute limb ischemia in patients with cancer

BACKGROUND

Cancer results in a hypercoagulable state that is associated with both venous and arterial thromboses. However, little is known about the effects of acute limb ischemia (ALI) in this cohort of patients. In the present systematic review and meta-analysis, we analyzed the available clinical data on cancer and its association with ALI and evaluated the outcomes in these patients after a diagnosis of ALI.

METHODS

Three databases, including PubMed, EMBASE, and the Cochrane Library, were queried. Studies that met the inclusion criteria were included regardless of the publication year, language, sample size, or follow-up length. All the steps of the meta-analysis were conducted in accordance with the PRISMA (preferred reporting items for systematic reviews and meta-analyses) and MOOSE (meta-analysis of observational studies in epidemiology) guidelines.

RESULTS

Seven studies from 6222 references with a total of 2899 patients were included. Of the 2899 patients, 1195 (41%) had had a diagnosis of ALI before their cancer diagnosis, and 1704 (59%) had presented with ALI after a cancer diagnosis. Nearly three quarters of ALI events were among patients with cancer of the skin and soft tissue (19%), genitourinary (18%), lung (17%), and gastrointestinal (16%) systems. ALI recurrence was similar between the two groups, and major amputation was more likely in patients with a diagnosis of ALI after a cancer diagnosis (7.4% vs 4.6%; P < .01). The incidence of mortality at 1 year was significantly greater for patients with established cancer who had presented with ALI compared with the patients who had presented with ALI before a cancer diagnosis (50.6% vs 29.9%; P < .01). After adjusting for study variability using the random effects model, the mortality at 1 year for all patients was 52.3% (95% confidence interval, 37.7%-66.5%). No significant heterogeneity (P = .73) was found between the two groups of patients, which varied by the timing of the ALI diagnosis in relation to the cancer diagnosis.

CONCLUSIONS

The 1-year mortality after the development of ALI in patients with cancer was >50%. For patients presenting with ALI of unclear etiology, the presence of an underlying cancer should be considered.

The effect of deep vein thrombosis on major adverse limb events in diabetic patients: a nationwide retrospective cohort study

Little is known about the association between deep vein thrombosis (DVT) and arterial complications in patients with type 2 diabetes (T2DM). The aim of this retrospective cohort study was to assess the influence of prior DVT on major adverse limb events (MALEs) and major adverse cardiovascular events (MACEs) in T2DM. A total of 1,628,675 patients with T2DM with or without a history of DVT from 2001 to 2013 were identified in the National Health Insurance Research Database of Taiwan. Before matching, the patients in the DVT group (n = 2020) were older than the control group (66.3 vs. 58.3 years). Patients in the DVT group were more likely to be female than the control group (54.3% vs. 47.5%). Before matching, the DVT group had higher prevalence of most comorbidities, more prescription of antiplatelet, antihypertensive agents and insulins, but less prescription of metformin and sulfonylurea. During a mean follow-up of 5.2 years (standard deviation: 3.9 years), the matched DVT group (n = 2017) have a significantly increased risk of MALE (8.4% vs. 5.2%; subdistribution hazard ratio [SHR] 1.60, 95% CI 1.34–1.90), foot ulcer (5.2% vs. 2.6%, SHR 1.96, 95% CI 1.57–2.45), gangrene (3.4% vs. 2.3%, SHR 1.44, 95% CI 1.10–1.90) and amputation (2.5% vs. 1.7%; SHR 1.42, 95% CI 1.03–1.95) than the 10,085 matched controls without DVT. They also tended to have a greater risk of all-cause mortality (38.1% vs. 33.1%; hazard ratio [HR] 1.18, 95% CI 1.09–1.27) and systemic thromboembolism (4.2% vs. 2.6%; SHR 1.56, 95% CI 1.22–1.99), respectively. We showed the presence of DVT may be associated with an increased risk of MALEs, major amputation, and thromboembolism, contributing to a higher mortality rate in T2DM.