Ankle Brachial Pressure Index: An update for the vascular specialist and general practitioner

The Accuracy and Reliability of Automated Oscillometric Measurement of Ankle-Brachial Index in the Diagnosis of Peripheral Artery Disease

BACKGROUND

Comparing the accuracy and reliability of ankle-brachial index (ABI) measured by an oscillometric device with the Doppler method in peripheral arterial disease (PAD).

METHODS

122 patients admitted to the department of interventional radiology with PAD were studied. ABI was measured with the 2 methods in random order. After excluding the inconclusive results, Doppler ABIs were compared with the oscillometric ABIs in each limb, the reliability was evaluated by intraclass correlation coefficient (ICC), and the accuracy and consistency were assessed by receiver operating characteristic curves and Bland-Altman method.

RESULTS

In 122 patients (244 legs), 27 legs got inconclusive oscillometric results, 4 legs got inconclusive oscillometric and inconclusive dorsalis pedis artery Doppler results, 2 legs had oscillometric cuff pressure intolerance. Using Doppler ABI <0.9 as a diagnostic threshold, compared with the high Doppler ABI, oscillometric method had a sensitivity of 57.81%, a specificity of 95.18%, the ICC was 0.626 (95% confidence interval [CI]: 0.536-0.701), Bland-Altman method showed 11/211 (5.21%) difference points outside the 95% limits of agreement. Compared with the low Doppler ABI, oscillometric method had a sensitivity of 50.66%, a specificity of 98.31%, the ICC was 0.541(95% CI: 0.483-0.630), Bland-Altman method showed 11/211 (5.21%) difference points outside the 95% limits of agreement. Using 1.00 as the diagnostic threshold and considering error oscillometric results as abnormal ABIs, the sensitivity improved to 88.05% with high Doppler ABI and 81.42% with the low.

CONCLUSIONS

The accuracy and reliability of oscillometric ABI in patients with PAD is unsatisfied, which makes it not suitable as an alternative method in clinic disease assessment. Using 1.0 as the ABI oscillometric threshold for PAD diagnosis can improve the diagnostic value.

The evolution of leg ulcer guidelines and recommendations

BACKGROUND

Clinical guidelines aim to consolidate and incorporate the latest evidence and opinion to improve patient outcomes and reduce variations in practice.

AIMS AND METHODS

This article will examine the evolution of clinical guidelines and recommendations in leg ulcer assessment and management, from the seminal Royal College of Nursing clinical guideline (1998) to the current Leg Ulcer Recommendations from the National Wound Care Strategy Program (2023). The evolving definitions of leg ulcers will be discussed, as well as the multidisciplinary approach needed to manage the underlying aetiology of this condition.

FINDINGS AND CONCLUSION

A national appetite for improving leg ulcer assessment and treatment, is being informed by clinical guidelines and recommendations. The cornerstones of assessment and management remain constant, although some fundamental elements around ankle brachial pressure index ranges, historically used to aid diagnosis of leg ulcer aetiology, have been omitted in the recent recommendations.

The ankle-brachial index for assessing the prevalence of peripheral artery disease and cardiovascular risk in patients with type 2 diabetes mellitus

BACKGROUND AND AIMS

Type 2 diabetes mellitus (T2DM) is an important risk factor for peripheral artery disease (PAD). Ankle-Brachial Index (ABI) was found associated with a higher cardiovascular (CV) risk and mortality. The main goals of this study were to establish the prevalence of PAD in a T2DM population, and assess the relationship between PAD and the CV risk calculated with the CUORE Project score (CPS) (https://www.cuore.iss.it/). The association between the ABI, the main risk factors for PAD and T2DM complications was also investigated.

METHODS AND RESULTS

Two hundred patients were consecutively enrolled. The prevalence of PAD in this population was 17%. The CV risk tended to be higher (p = 0.0712) in the group with a pathological ABI than in the group with a normal ABI. Glycated hemoglobin (r = -0.1591; p = 0.0244), total cholesterol (r = -0.1958; p = 0.0054), LDL cholesterol (r = -0.1708; p = 0.0156) and systolic blood pressure (r = -0.1523; p = 0.0313) correlated significantly and inversely with the left ABI. The frequency of diabetic retinopathy was significantly higher in the group with a pathological ABI (p = 0.0316).

CONCLUSIONS

The data reveal a high prevalence of PAD in patients with T2DM. The CPS confirmed that patients with a pathological ABI have tendency to a higher CV risk. The results point to the importance of an accurate CV assessment - also measuring individuals' ABI and calculating their CPS - to better pinpoint those at high risk of PAD, especially among patients with T2DM.

Ankle-brachial index: more than a diagnostic test?

The ankle-brachial index (ABI) is the relationship between the systolic blood pressure taken at the ankle level and the brachial artery. A pathological ABI (<0.90 or >1.40) indicates the presence of peripheral artery disease (PAD). Many studies indicate the great utility of this test in the diagnosis of PAD due to its ease of use, reproducibility, low cost, and high cost-effectiveness. This evaluation can be directly correlated with cardiovascular morbidity and mortality; however, it has recently been confirmed that a low ABI can be a predictor of major cardiovascular events, as it is related to diabetes mellitus, chronic coronary disease, stroke, and more. The objective of this work was to review the current evidence on the importance of ABI in the diagnosis of PAD and its main role as a predictor of cardiovascular morbidity and mortality.

Predictive Value of Limb Artery Indices and Endothelial Functional Tests for the Degree of Coronary Artery Stenosis in a Diabetic Population

Objective

To investigate the correlation between limb artery indices (brachial-ankle pulse wave velocity and ankle-brachial index), endothelial function index (FMD value), and the degree of coronary artery stenosis in diabetic patients and analyze their values in predicting the degree of coronary artery stenosis.

Methods

The study included 151 patients with type 2 diabetes mellitus and suspected coronary atherosclerotic heart disease. The patients were divided into “coronary atherosclerotic heart disease” (N=94) and “non-coronary atherosclerotic heart disease” (N=57) groups based on the coronary angiographic findings. Within the coronary atherosclerotic heart disease group, the patients were further divided into “low stenosis” (N=47) and “high stenosis” (N=47) subgroups according to their Gensini score. Indicators such as brachial-ankle pulse wave velocity, ankle-brachial index, and FMD value were measured and correlated with the degree of coronary artery stenosis. Logistic regression models were constructed and receiver operating characteristic curves plotted to assess the predictive ability of limb artery and endothelial functional indices for the degree of coronary artery stenosis.

Results

In a diabetic population, FMD value (P=0.003), ankle-brachial index (P=0.004), and brachial-ankle pulse wave velocity (P=0.003) were different in patients with and without coronary atherosclerotic heart disease. In the population with both diabetes mellitus and coronary atherosclerotic heart disease, the ankle-brachial index and FMD value were both independently associated with the degree of coronary artery stenosis (P=0.003). The area under the receiver operating characteristic curve plotted from the combined coefficients of ankle-brachial index and FMD value was 0.773, which is predictive of coronary artery stenosis in diabetic patients.

Conclusion

Ankle-brachial index and FMD value are indicative of the degree of coronary artery stenosis in diabetic patients, and predictive efficacy can be improved by combining the two tests.

Long-term effects of a food pattern on cardiovascular risk factors and age-related changes of muscular and cognitive function

INTRODUCTION

The mean age of the German population increased over the last years, which resulted in a higher prevalence of cardiovascular diseases, type 2 diabetes, cognitive impairment, sarcopenia and bone fractures. Current evidence indicates a preservation of human wellbeing in the elderly by a healthy diet, although the recommended macronutrient composition and quality remains unclear and needs further long-term investigation. In this context we investigate the effect of a specific dietary pattern on age-related disorders in a randomized controlled multi-center trial (RCT).

METHODS

We assess the effect of a specific dietary pattern (NutriAct) with a high proportion of unsaturated fat, plant proteins and fibres (fat 35%-40% of total energy (%E) of which 15%E-20%E monounsaturated fatty acids (MUFA) and 10%E-15%E polyunsaturated fatty acids (PUFA), 15%E-25%E proteins, ≥30 g fibres per day and 35%E-45%E carbohydrates) on age-related impairment of health within a 36-months RCT conducted in the region of Berlin and Potsdam. 502 eligible men (n = 183) and women (n = 319), aged 50 to 80 years, with an increased risk to develop age-related diseases were randomly assigned to either an intervention group focusing on NutriAct dietary pattern or a control group focusing on usual care and dietary recommendations in accordance to the German Nutrition Society (DGE). In the intervention group, 21 nutrition counsellings as well as supplementation of rapeseed oil, oil cake and specific designed foods are used to achieve the intended NutriAct dietary pattern.The primary outcome is a composite endpoint of age-related disorders, including cardiovascular morbidity, decline of cognitive function as well as clinical features of sarcopenia. Secondary outcomes include diet-induced effects on quality of life, depression, frailty, cardiovascular function, bone density, fat distribution pattern, glucose, lipid and energy metabolism, as well as the identification of biomarkers linked with age-related disorders.

DISCUSSION

The findings of this trial will provide clinically relevant information regarding dietary effects on age-related impairment of health and will contribute to the definition of the optimal macronutrient composition in the context of healthy aging in the German population.

Increased Elastin Degradation in Pseudoxanthoma Elasticum Is Associated with Peripheral Arterial Disease Independent of Calcification

Pseudoxanthoma elasticum (PXE) results in extensive fragmentation and calcification of elastin fibers in the peripheral arteries, which results in peripheral arterial disease (PAD). Current research focuses on the role of calcifications in the pathogenesis of PXE. Elastin degradation and calcification are shown to interact and may amplify each other. This study aims to compare plasma desmosines, a measure of elastin degradation, between PXE patients and controls and to investigate the association between desmosines and (1) arterial calcification, (2) PAD, and (3) PAD independent of arterial calcification in PXE. Plasma desmosines were quantified with liquid chromatography-tandem mass spectrometry in 93 PXE patients and 72 controls. In PXE patients, arterial calcification mass was quantified on CT scans. The ankle brachial index (ABI) after treadmill test was used to analyze PAD, defined as ABI < 0.9, and the Fontaine classification was used to distinguish symptomatic and asymptomatic PAD. Regression models were built to test the association between desmosines and arterial calcification and arterial functioning in PXE. PXE patients had higher desmosines than controls (350 (290–410) ng/L vs. 320 (280–360) ng/L, p = 0.02). After adjustment for age, sex, body mass index, smoking, type 2 diabetes mellitus, and pulmonary abnormalities, desmosines were associated with worse ABI (β (95%CI): −68 (−132; −3) ng/L), more PAD (β (95%CI): 40 (7; 73) ng/L), and higher Fontaine classification (β (95%CI): 30 (6; 53) ng/L), but not with arterial calcification mass. Lower ABI was associated with higher desmosines, independent from arterial calcification mass (β (95%CI): −0.71(−1.39; −0.01)). Elastin degradation is accelerated in PXE patients compared to controls. The association between desmosines and ABI emphasizes the role of elastin degradation in PAD in PXE. Our results suggest that both elastin degradation and arterial calcification independently contribute to PAD in PXE.

Peripheral artery disease in outpatients with a recent history of acute coronary syndrome or at high atherothrombotic risk

OBJECTIVES

The frequency and implications of peripheral artery disease (PAD) in some risk groups are not entirely characterized in Latin America. We studied PAD prevalence, risk factors, and six-month outcomes in stable outpatients with a history of a recent acute coronary syndrome (ACS), or at high coronary risk.

METHODS

We recruited 830 outpatients in 43 Mexican sites (median age: 64.8 years; 57.8% men). Inclusion criteria were age >18 years, and ACS within 30 days, or age <55 years plus ≥2 major vascular risk factors, or age ≥55 years plus ≥1 vascular risk factors. Patients received standardized assessments at baseline and six-month follow-up for medical history, ankle-brachial index (ABI), and the Edinburgh Claudication Questionnaire (ECQ).

RESULTS

ABI <0.8 was found in 10.5%, <0.9 in 22.5%, >1.3 in 4.8%, and >1.4 in 3.6%, without differences according to sex or selection criteria. Positive ECQ was found in 7.6%. ABI <0.9 was directly associated with age, diabetes, ACS, and chronic kidney disease, but inversely associated with BMI >27. The six-month case-fatality and atherothrombotic events rates were 1.6% and 3.6%, respectively. In patients with ABI <0.9 and ABI <0.8, the six-month case-fatality rates were 2.5% (p = 0.27) and 5.4% (p = 0.03), respectively. In a Cox proportional-hazards model, baseline factors associated with death were age ≥65, ABI <0.8, and ACS.

CONCLUSIONS

Subclinical PAD is more common than symptomatic claudication in high-risk coronary outpatients. Low ABI is associated with reduced short-term survival in patients with recent ACS or at high coronary risk.