Office management of peripheral arterial disease

Monitoring antiplatelet therapy: where are we now?

Single antiplatelet therapy represents the cornerstone of thrombosis prevention in atherosclerotic cardiovascular disease. Dual antiplatelet therapy (DAPT), consisting of aspirin plus a P2Y12 inhibitor, is the standard of care for patients with acute coronary syndrome or undergoing both coronary and peripheral percutaneous interventions. Recent data suggest the efficacy of DAPT also after minor stroke. In this setting, a large body of evidence has documented that genetic and acquired patients' characteristics may affect the magnitude of platelet inhibition induced by antiplatelet agents. The implementation of tools allowing the identification and prediction of platelet inhibition has recently been shown to improve outcomes, leading to an optimal balance between antithrombotic efficacy and bleeding risk. We are therefore clearly moving towards tailored antiplatelet therapy. The aim of this paper is to summarize the available evidence on the evaluation of platelet inhibition in patients with coronary, peripheral, or cerebrovascular atherosclerosis. We will here focus on antiplatelet therapy based on both aspirin and P2Y12 inhibitors. In addition, we provide practical insights into the clinical settings in which it appears reasonable to implement antiplatelet therapy monitoring.

Peripheral Artery Disease and Abdominal Aortic Aneurysm: The Forgotten Diseases in COVID-19 Pandemic. Results from an Observational Study on Real-World Management

Background and Objectives: It is well established that patients with peripheral artery disease (PAD) as well abdominal aortic aneurysm (AAA) have an increased cardiovascular (CV) mortality. Despite this higher risk, PAD and AAA patients are often suboptimality treated. This study assessed the CV profile of PAD and AAA patients, quantifying the survival benefits of target-based risk-factors modification even in light of the COVID-19 pandemic. Materials and Methods: PAD and AAA patients admitted for any reason to the Vascular Unit from January 2019 to February 2020 were retrospectively analyzed. Biochemical and CV profiles as well as ongoing medical therapies were recorded. Benefits of CV risk-factors control were estimated using the SMART-REACH model. A follow-up visit during the year 2020 was scheduled. Results: A total of 669 patients were included. Of these, 190 showed AAA and 479 PAD at any stage. Only 54% of PAD and 41% of AAA patients were on lipid-lowering drugs with non-optimal low-density lipoprotein (LDL) levels for most of them. A better control of all modifiable CV risk-factors based on the current guidelines would offer an absolute risk reduction of the mean 10-year CV risk by 9% in PAD and 14% in AAA. Unfortunately, the follow-up visit was lost because of COVID-19 limitations. Conclusions: Lipid profiles of PAD and AAA patients were far from guideline-based targets, and medical management was suboptimal. In our center, the COVID-19 pandemic impacted on the strict surveillance required in these very high-risk patients. The achievement of guideline-based therapeutic targets would definitively confer additional significant benefits in reducing the CV risk in these patients.

Carotid intima-media thickness and plaques in internal carotid artery as surrogate markers of lower limb arterial lesions in Chinese patients with diabetic foot

Peripheral arterial disease (PAD) can impair healing of diabetic foot (DF) in patients with diabetes mellitus. To determine whether carotid intima-media thickness (CIMT) can predict lower limb arterial lesions in patients with DF, this cross-sectional study enrolled patients with DF at West China Hospital (China) between January 2012 and December 2015. Ultrasonography was used to measure CIMT, assess the internal carotid arteries (ICA) for plaques, and evaluate lower limb segmental arteries for stenosis. The optimal CIMT cutoff for detecting lower limb PAD was determined by receiver operating characteristic (ROC) curve analysis. Factors associated with PAD were identified by logistic regression analyses. A total of 167 patients (mean age: 69.7±10.3 years; 102 men) were included. Patients with PAD were older and had higher levels of total cholesterol and low-density lipoprotein than patients without PAD (P<0.05). The area under the ROC curve was 0.747 (P<0.001). At the optimal CIMT cutoff of 0.71 mm, the sensitivity, specificity, positive predictive value, and negative predictive value were 79.65, 61.11, 81.08, and 58.93%, respectively. Compared with those without PAD, more patients with PAD had CIMT ≥0.71 mm (79.65 vs 38.89%; P<0.001) and ICA plaques (66.37vs 11.11%; P<0.001). Multivariate logistic regression revealed that age (odds ratio [OR]: 1.118; 95% confidence interval [95%CI]: 1.056–1.183; P<0.001), ICA plaques (OR: 13.452; 95%CI: 4.450–40.662; P<0.001), and CIMT ≥0.71 mm (OR: 2.802; 95%CI: 1.092–7.188; P=0.032) were associated with PAD.CIMT may be a surrogate marker of PAD in patients with DF.

Multidisciplinary Approach to PAD: Who's on Your Team?

The complexity of peripheral arterial disease (PAD) and its multiorgan involvement requires the utilization of a multispecialty team approach. Members of this team include a vascular specialty (interventional radiology, cardiology, and vascular surgery), podiatry, orthopedic surgery, primary care, infectious disease, endocrinology, plastic surgery, wound care nursing, and dietetics. A team approach has been proven to significantly improve patient outcomes as well as decreasing amputation rates. In order to promote collaboration and avoid duplication of care, the team can be broken down into three main pillars: medical management, wound care, and revascularization. A complete team approach is vital for this population, with an overall goal to treat all manifestations of the disease and prevent further progression and risk of major sequelae of the disease.

Analysis of ischemic muscle in patients with peripheral artery disease using X-ray spectroscopy

BACKGROUND

Peripheral artery disease (PAD) is a vascular disease caused by atherosclerosis, resulting in decreased blood flow to the lower extremities. The ankle-brachial index (ABI) is a standard PAD diagnostic test but only identifies reduced blood flow based on blood pressure differences. The early signs of PAD manifest themselves not only at a clinical level but also at an elemental and biochemical level. However, the biochemical and elemental alterations to PAD muscle are not well understood. The objective of this study was to compare fundamental changes in intracellular elemental compositions between control, claudicating, and critical limb ischemia muscle tissue.

MATERIALS AND METHODS

Gastrocnemius biopsies from three subjects including one control (ABI ≥ 0.9), one claudicating (0.4 ≤ ABI < 0.9), and one critical limb ischemia patient (ABI < 0.4) were evaluated using a scanning electron microscope and energy dispersive X-ray spectroscopy to quantify differences in elemental compositions. Spectra were collected for five myofibers per specimen. An analysis of variance was performed to identify significant differences in muscle elemental compositions.

RESULTS

This study revealed that intracellular magnesium and calcium were lower in PAD compared with control myofibers, whereas sulfur was higher. Magnesium and calcium are antagonistic, meaning, if magnesium concentrations go down calcium concentrations should go up. However, our findings do not support this antagonism in PAD. Our analysis found decreases in sodium and potassium, in PAD myofibers.

CONCLUSIONS

These findings may provide insight into the pathologic mechanisms that may operate in ischemic muscle and aid in the development of specialized preventive and rehabilitative treatment plans for PAD patients.

CT angiography of the lower extremity and coronary arteries using 256-section CT: a preliminary study

AIM

To investigate the possible use of a 256-section computed tomography (CT) prospective electrocardiography (ECG)-gated wide volume scanning protocol for combined angiography of the lower extremity and coronary arteries, after a single injection of contrast medium, in patients with lower extremity peripheral arterial disease (PAD).

MATERIALS AND METHODS

Thirty-four patients with suspected PAD underwent CT angiography (CTA) with a prospective ECG-gated protocol that covered the level of the tracheal bifurcation to the foot sole. Digital subtraction angiography (DSA) of the lower extremity arteries was performed on patients requiring therapeutic intervention. Image quality and stenosis of the coronary and lower extremity arteries were assessed.

RESULTS

A total of 93.1% of the coronary segments were adequate for diagnosis. 17 (50%) patients showed coronary artery stenosis ≥50%. A total of 95.8% of the lower extremity arterial segments were adequate for diagnosis. Twenty-eight patients with severe lower extremity arterial stenosis or occlusion underwent DSA. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CTA for the detection of significant lower arterial stenosis (≥50%) was 94.8%, 97.2%, 95.3%, 96.9%, and 96.3%, respectively.

CONCLUSION

Using the prospective ECG-gated wide volume CTA protocol, images of the coronary and lower extremity arteries suitable for diagnosis can be acquired simultaneously after a single injection of contrast agent. In addition to accurately diagnosing PAD, combined angiography may be used to screen for coronary heart disease in patients with PAD.

Invasively-treated incidence of lower extremity peripheral arterial disease and associated factors in Taiwan: 2000-2011 nationwide hospitalized data analysis

BACKGROUND

Lower extremity (LE) peripheral artery disease (PAD), which is associated with a reduced quality of life and increased mortality from atherosclerotic cardio-/cerebro-vascular occlusion, is a significant public health problem, especial for an aging society such as that of Taiwan.

METHODS

Specific datasets of the 2000-2011 nationwide inpatient databases were analyzed. Two inclusion criteria, including one of the major diagnosis codes of PAD and one of three categorical invasive treatments of LE PAD, were used consecutively to select cases diagnosed as LE PAD and receiving invasive treatment. The epidemiology of invasively-treated PAD in Taiwan was estimated, and the influences of potential confounders on these invasively-treated methods were evaluated.

RESULTS

In general, the invasively-treated incidence of PAD in Taiwan doubled, from 3.73/10,000 (in 2000) to 7.48/10,000 (in 2011). On average, the total direct medical cost of one hospitalized and invasively-treated PAD case ranged from $US 4,600 to $US 5,900. The annual cases of bypass surgery for the PAD cases averaged 1,000 and the cases for limb amputation ranged from 4,100 to 5,100 annually. However, the number of percutaneous transluminal angioplasty (PTA) procedures remarkably increased by 15 times, from 600/year to 9,100/year, from 2000 to 2011. 51.3% of all the enrolled cases were treated with limb amputations, and female, young and middle-aged people (30-65 years of age), DM patients and those on a low income had a tendency to undergo amputation due to PAD. 37.6% of all the enrolled cases were treated with PTAs related to hypertension, cardiovascular disease, hyperlipidemia and catastrophic Illness. 2-year PTA failure rates of 22.13%, 11.91% and 10.61% were noted among the first (2000-2001), second (2004-2005) and the third (2008-2009) cohort groups, respectively.

CONCLUSIONS

In Taiwan, a gender difference and age and period effects on the invasively-treated incidence of LE PAD were observed. Female, young and middle-aged people (30-50 and 50-65 years of age), DM patients and those on a low income had a tendency to undergo amputation. The number of PTA procedures remarkably increased, but the 2-year failure rate of PTAs reduced from 2000 to 2011.

Foot care practice - the key to prevent diabetic foot ulcers in India

BACKGROUND

The magnitude of diabetic foot ulcers (DFUs) and the amputation rates due to DFUs remain high even in developing and developed countries. Yet, the influence of knowledge, attitude, and practice (KAP) of diabetic foot care (DFC) on DFU incidence is not studied much.

OBJECTIVE

To study causal relationship between knowledge, attitude and practice (KAP) on DFC between diabetic patients with and without DFUs; and the risk factors associated with DFUs.

METHODS

A consecutive of 203 diabetic patients (103 with DFU and 100 without DFU) were included in the study. Their demographic details, medical history, and personal habits were recorded. KAP on DFC was assessed using a questionnaire. Responses were recorded, scored, and analyzed.

RESULTS

Of the cohort, 67.5% were males, mean age: 59.9 ± 11.4 years. Patients without DFU had good knowledge on DFC compared to those with DFU (86% versus 69.9%) (p<0.001). Incidence of DFU was 9% and 39.8% (p<0.001) among patients who practiced and not practiced DFC respectively. 88% patients with and without DFUs; showed favorable attitude toward adopting DFC. Risk factors - diabetic peripheral neuropathy, peripheral vascular disease, retinopathy, nephropathy, smoking, tobacco chewing and alcohol consumption were significantly (p<0.001) associated with DFUs.

CONCLUSIONS

An inverse relationship between DFU and foot care knowledge as well as practice was observed. Apart from tight glycemic control, diabetic patients must be educated and motivated on proper foot care practice and life style modifications for preventing DFUs.

African Americans and Peripheral Arterial Disease: A Review Article

Peripheral arterial disease (PAD)—atherosclerosis of the abdominal aorta and arteries of the lower extremities—affects 12 million Americans. African Americans (AAs) are more than twice as likely as non-Hispanic whites to suffer from PAD. When compared to non-Hispanic whites with PAD, AAs with PAD have more severe disease and a greater reduction in walking distance, speed, and/or stair climbing. AAs with PAD are at increased risk for disease progression and worsening lower limb function. Reasons for the higher risk for disease progression have not been defined. One potential modifiable risk is a lower level of physical activity. Lower levels of physical activity are more common among African American seniors. Walking is a common type of physical activity. The benefits of walking therapy are only realized if the patient adheres to such therapy. Efforts are needed to increase walking in AAs with PAD. Additionally, risk factor management is key to reducing adverse events in AAs with PAD-yet few studies have targeted this high-risk group. In this paper, we discuss the management of PAD in AAs. Identifying current gaps will help to inform clinicians, researchers, and policy makers on next steps in identifying innovative approaches to increase home-based walking and reduce walking impairment in AAs with PAD.

Antiplatelet therapy in peripheral artery disease

Peripheral artery disease (PAD) is a term that relates to atherosclerosis and narrowing of the arteries in the lower extremities. The prevalence of PAD is approximately 12% of the adult population. Despite the low rate of peripheral complications and amputation, PAD is complicated by a high rate of cardiovascular events including myocardial infarction, stroke, and vascular death with an annual incidence of about 5%.The detection of PAD is initially based on the appearance of typical symptoms (claudication and critical limb ischemia) related to peripheral arterial insufficiency. However, PAD may also be present in the absence of clinical symptoms (asymptomatic PAD). Accordingly, asymptomatic disease may occur in up to 50% of all patients with PAD. Ankle brachial index (ABI) is a diagnostic test used to evaluate the presence of PAD, defined by an ABI ≤0.90. The ABI is also demonstrated to be useful in the assessment of vascular risk in asymptomatic and symptomatic patients. Antiplatelet therapy remains a key intervention to reduce cardiovascular risk in PAD. Data from Antithrombotic Trialists' Collaboration showed that antiplatelet treatment was associated with a 23% risk reduction of vascular events in overall population with PAD. However, closer scrutiny of these data reveals that nonaspirin antiplatelet drugs, including ticlopidine, clopidogrel, picotamide, and dipyridamole largely drove the benefits in the PAD subgroup. It remains an open issue if PAD represents an atherosclerotic clinical model where aspirin, differently from coronary heart disease, is less effective in reducing atherosclerotic progression. Based on the reported results further trials with aspirin should be done in asymptomatic (ABI ≤0.90) and symptomatic PAD patients. Finally, the role of new antiplatelet drugs such as prasugrel and ticagrelor has not yet been studied in PAD.

Effect of guideline orientation on the outcomes of peripheral arterial disease in primary care

OBJECTIVE

Peripheral arterial disease (PAD), an established marker of premature death and cardiovascular risk in general, is highly prevalent. We analysed factors associated with poor outcomes in an observational cohort, with particular focus on the effect of guideline orientation in the management of these patients.

METHODS

PACE-PAD is a multicentre, prospective, observational study of PAD patients in primary care. PAD guideline orientation was stated, if patients received the following: exercise training, (if applicable) advice for smoking cessation and diet, therapy for diabetes mellitus, hypertension, hypercholesterolaemia, or antiplatelets/anticoagulants. Multivariate regression models were applied to assess factors associated with all cause death, cardiovascular/cerebrovascular death, or cardiovascular/cerebrovascular/peripheral vascular non-fatal events.

RESULTS

After an 18-month follow-up, of the 5099 PAD patients analysed (mean age 68.0 ± 9.0 years, 68.5% males), only 28.4% of patients met all applicable quality indicators for guideline-oriented treatment. However, most patients were to a large extent managed in line with guidelines. While exercise training was reported in 41.8%, rates were very high for smoking cessation (90.7%), therapy for hypertension (92.5%), diabetes mellitus (82.0%), hypercholesterolemia (83.3%) and antiplatelet therapy (86.7%). Regarding events, there were inhomogeneous results with a statistically significant higher rate of cardiovascular/cerebrovascular deaths and all-cause deaths, but a lower rate of non-fatal vascular events in patients treated according to guidelines compared to those who were not. Limitations of this study include the open, non-controlled design, possible patient selection bias and misclassification of events.

CONCLUSION

Even if the guideline orientation for the various indicators was remarkably stable across the three follow-up visits, the rate of patients comprehensively treated according to the guidelines was relatively low, which calls for optimisation. There was a lack of differentiation between the guideline-oriented and non-guideline-oriented therapy in terms of outcomes, which may be due to patient-related or other factors, and warrants further research.