Cost-effectiveness analysis of routine computed tomography angiography (CTA) for lower extremity penetrating trauma.

BACKGROUND: Routine evaluation with CTA for patients with isolated lower extremity penetrating trauma and normal ankle-brachial-indices (ABI) remains controversial. While prior literature has found normal ABI's (≥0.9) and a normal clinical examination to be adequate for safe discharge, there remains concern for missed injuries which could lead to delayed surgical intervention and unnecessary morbidity. Our hypothesis was that routine CTA after isolated lower extremity penetrating trauma with normal ABIs and clinical examination is not cost-effective. METHODS: We performed a decision-analytic model to evaluate the cost-effectiveness of obtaining a CTA routinely compared to clinical observation and ABI evaluation in hemodynamically normal patients with isolated penetrating lower extremity trauma. Our base case was a patient that sustained penetrating lower extremity trauma with normal ABIs that received a CTA in the trauma bay. Costs, probability, and Quality-Adjusted Life Years (QALYs) were generated from published literature. RESULTS: Clinical evaluation only (no CTA) was cost-effective with a cost of $2056.13 and 0.98 QALYs gained compared to routine CTA which had increased costs of $7449.91 and lower QALYs 0.92. Using one-way sensitivity analysis, routine CTA does not become the cost-effective strategy until the cost of a missed injury reaches $210,075.83. CONCLUSIONS: Patients with isolated, penetrating lower extremity trauma with normal ABIs and clinical examination do not warrant routine CTA as there is no benefit with increased costs.

Role of Hemodynamic Assessment and Limitations in Ankle-Brachial Pressure Index, Toe- Brachial Pressure Index to Predict Wound Healing After Revascularization.

Chronic limb-threatening ischemia (CLTI) represents one of the most severe forms of peripheral arterial disease implying impaired wound healing and tissue loss at the same time posing a significant impact on the quality of life of patients and a serious economic burden on healthcare systems around the world. A major challenge in the management of patients with CLTI is the validity and role of non-invasive hemodynamic parameters in assessing their clinical status before and after revascularization. Traditionally, the diagnosis of CLTI is routinely based on clinical symptoms and confirmed by measurements of non-invasive limb hemodynamics including ankle-brachial pressure index (ABPI) and toe-brachial pressure index (TBPI). However, whether these indices alone can provide definitive treatment or be used as adjunctive tool along with the implementation of novel techniques to help guide revascularization for CLI patients still remains unclear.

[Clinical value of arterial stiffness assessment on risk prediction of vascular stiffness in the octogenarian elderly].

Objective: This study aimed to analyze clinical factors related to arterial stiffening and establish a risk prediction nomogram of arterial stiffening in the octogenarian(≥80 years). Methods: This study was a retrospective cross-sectional study, which enrolled the octogenarian elderly who underwent physical examination and secondary prevention intervention in the outpatient department of Chinese People's Liberation Army General Hospital from April 2022 to August 2022. Clinical data including demographics, biochemical indicators and medical history were collected. Brachial-ankle pulse wave velocity (baPWV) was detected during the clinical visit. Participants were divided into the control group (baPWV≤1 800 cm/s) and vascular sclerosis group (baPWV>1 800 cm/s). The risk factors of arterial stiffness were analyzed by univariate and logistic regression analysis, and the nomogram model was constructed by R programming language. The predictive effect of the nomogram model was evaluated by the receiver operating characteristic curve (ROC). Results: The median age of the 525 participants was 87.0 (82.0, 92.0) years, 504 (96.0%) were male, 82 in the control group, 443 in the vascular sclerosis group. The baPWV, age, systolic blood pressure, mean arterial pressure and diastolic blood pressure were significantly lower in the control group than those in the vascular sclerosis group (all P<0.05). Logistic regression analysis showed that high-density lipoprotein cholesterol, alanine aminotransferase and amylase were protective factors, and alkaline phosphatase and creatinine were risk factors of arterial stiffening (all P<0.05). The combined nomogram model scores including age, mean arterial pressure and the above five laboratory indicators indicated that mean arterial pressure and serum creatinine levels were strongly correlated with vascular sclerosis. The ROC curve suggested that the nomogram model had good prediction ability. Conclusions: Age, mean arterial pressure, high-density lipoprotein cholesterol, alanine aminotransferase, alkaline phosphatase, amylase and creatinine are independently determinants for increased vascular stiffness. The combined prediction model in this study can provide reference for individualized clinical risk prediction of vascular sclerosis in the octogenarian elderly.

Contrast-free ultrasound imaging for blood flow assessment of the lower limb in patients with peripheral arterial disease: a feasibility study.

While being a relatively prevalent condition particularly among aging patients, peripheral arterial disease (PAD) of lower extremities commonly goes undetected or misdiagnosed due to its symptoms being nonspecific. Additionally, progression of PAD in the absence of timely intervention can lead to dire consequences. Therefore, development of non-invasive and affordable diagnostic approaches can be highly beneficial in detection and treatment planning for PAD patients. In this study, we present a contrast-free ultrasound-based quantitative blood flow imaging technique for PAD diagnosis. The method involves monitoring the variations of blood flow in the calf muscle in response to thigh-pressure-cuff-induced occlusion. Four quantitative metrics are introduced for analysis of these variations. These metrics include post-occlusion to baseline flow intensity variation (PBFIV), total response region (TRR), Lag0 response region (L0RR), and Lag4 (and more) response region (L4 + RR). We examine the feasibility of this method through an in vivo study consisting of 14 PAD patients with abnormal ankle-brachial index (ABI) and 8 healthy volunteers. Ultrasound data acquired from 13 legs in the patient group and 13 legs in the healthy group are analyzed. Out of the four utilized metrics, three exhibited significantly different distributions between the two groups (p-value < 0.05). More specifically, p-values of 0.0015 for PBFIV, 0.0183 for TRR, and 0.0048 for L0RR were obtained. The results of this feasibility study indicate the diagnostic potential of the proposed method for the detection of PAD.

[Impact of individual and combined assessment of age- and sex-specific brachial-ankle pulse wave velocity and pulse pressure on all-cause mortality].

Objective: To evaluate the impact of individual and combined assessment of age- and sex-specific brachial-ankle pulse wave velocity (baPWV) and pulse pressure (PP) on all-cause mortality. Methods: This study is a prospective cohort study. Individuals participated in the Kailuan Study and completed baPWV measurements between 2010 and 2016 were included in this study. After stratifying by sex, 75th percentile baPWV and PP values for different age group were calculated at five years interval. BaPWV and PP values below the 75th percentile were defined as normal, and those above or equal to the 75th percentile were defined as increased. The participants were allocated to four groups according to their PP and baPWV status: normal baPWV/PP group, high baPWV/normal PP group, normal baPWV/high PP group and high baPWV/PP group. The primary outcome was all-cause mortality during the follow-up period. Cox proportional hazards models were used to explore the impact of individual and combined assessment of baPWV and PP on all-cause mortality events. Results: A total of 39 339 participants were enrolled in this study, aged (49.3±12.8) years, of which 28 731 (73.03%) were males. There were 23 268, 6 025, 6 210 and 3 836 cases in the normal baPWV/PP group, high baPWV/normal PP group, normal baPWV/high PP group and high baPWV/PP group, respectively. The average follow-up duration was (4.98±2.53) years. During the follow-up period, all-cause mortality occurred in 998 individuals. Multivariate Cox regression analysis showed increased risk of all-cause mortality in the high baPWV/normal PP group (HR=1.27, 95%CI 1.07-1.50), and in the high baPWV/PP group (HR=1.33, 95%CI 1.08-1.65) compared to the normal baPWV/PP group. Increased pulse pressure alone had no impcat on all-cause death (HR=1.06, 95%CI 0.87-1.29). Conclusions: The risk of all-cause mortality significantly increases with increased age-and sex-specific baPWV and PP values. BaPWV may be a better predictor of all-cause mortality than PP in this cohort.

What are the current diabetic foot assessment methods in private podiatry practices in Flanders, Belgium: an exploratory mixed method study.

BACKGROUND: Diabetic foot assessments detect patients at risk for developing a diabetes-related foot ulceration and can significantly reduce the risk of amputation. In order to organize this assessment effectively, diabetic foot assessment guidelines are required according to the International Working Group of the Diabetic Foot. However, these international guidelines have not been adapted into a national guideline for podiatrists in Flanders, Belgium. This study aims to identify the methods and guidelines currently used to assess the diabetic foot in private podiatry practices in Flanders, Belgium and to explore the podiatrists' opinions on developing a national diabetic foot assessment guideline. METHODS: This exploratory mixed method study was composed of an anonymous online survey comprising of open- and closed-ended questions followed by 1:1 online semi-structured interviews. Participants were recruited via e-mail and a closed private Facebook group of podiatry alumni. Data was analyzed using SPSS statistics and thematic analysis described by Braun and Clarke. RESULTS: This study showed that the vascular assessment of the diabetic foot exists solely of a medical history and palpation of the pedal pulses. Non-invasive tests such as doppler, toe brachial pressure index or ankle brachial pressure index are seldom used. Only 66% reported to use a guideline for the diabetic foot assessment. There was a variety of reported guidelines and risk stratification systems in use in private podiatry practices in Flanders, Belgium. CONCLUSION: Non-invasive tests such as the doppler, ankle brachial pressure index or toe brachial pressure index are rarely used for the vascular assessment of the diabetic foot. Diabetic foot assessment guidelines and risk stratification systems to identify patients at risk for developing a diabetic foot ulcer were not frequently used. International guidelines of the International Working Group of the Diabetic Foot have not yet been implemented in private podiatry practices in Flanders, Belgium. This exploratory research has provided useful information for future research studies.

Assessment of microcirculatory changes in local tissue oxygenation after revascularization for peripheral arterial disease with the Hyperview®, a portable hyperspectral imaging device.

OBJECTIVES: The Hyperview® is a hyperspectral camera, which can be used to assess the microcirculation of patients with peripheral arterial disease (PAD) and/or diabetes mellitus (DM). It measures local tissue oxygenation in concentrations of oxyhemoblobin (OXY), deoxyhemoglobin (DEOXY), and O2-saturation (O2-SAT) in arbitrary units. The aim of this validation study is to assess whether the Hyperview® is able to monitor microcirculatory changes after revascularization in patients with PAD. METHODS: In this prospective observational cohort study, 50 patients with PAD were included who were scheduled for endovascular, hybrid, or open revascularization. The ankle-brachial index (ABI), systolic toe pressure (TP) (in case of DM), and a set of Hyperview® measurements of the plantar region were recorded before and after treatment. Changes in pre- and postoperative measurements were assessed with the paired t-test. RESULTS: Some 38 patients underwent endovascular revascularization and eight patients underwent hybrid or open vascular surgical revascularization. After revascularization, the ABI improved from 0.58 to 0.80 (p < 0.001). OXY increased from 72.6 to 77.8 (p = 0.134). DEOXY decreased from 69.1 to 55.0 (p < 0.001). O2-SAT increased from 51.3 to 58.1 (p < 0.001). TP improved from 50.6 to 61.9 mmHg (p = 0.065) but was measured in only 16 patients. CONCLUSION: The Hyperview® is able to observe changes in the microcirculation after revascularization in terms of DEOXY and O2-SAT. The results of this study are a promising step into the validation of the Hyperview®.

Prospective Assessment of the Diagnostic Accuracy of Multi-site Photoplethysmography Pulse Measurements for Diagnosis of Peripheral Artery Disease in Primary Care.

Peripheral arterial disease (PAD) is associated with cerebral and coronary artery disease. Symptomatic PAD affects about 5% of people over 55 years; many more have asymptomatic PAD. Early detection enables modification of arterial disease risk factors. Diagnostically, assessment of symptoms or signs can be unreliable; ankle brachial pressure index (ABPI) testing is time-consuming and few healthcare professionals are properly trained. This study assessed the diagnostic accuracy of multi-site photoplethysmography (MPPG), an alternative non-invasive test for PAD, in primary care. PAD patients identified from general practice registers were age- and sex-matched with controls. Participants were assessed using MPPG, ABPI and duplex ultrasound (DUS). Outcome measures were sensitivity and specificity of MPPG and ABPI (relative to DUS) and concordance. MPPG test results were available in 249 of 298 eligible participants from 16 practices between May 2015 and November 2016. DUS detected PAD in 101/249 (40.6%). MPPG sensitivity was 79.8% (95% confidence interval [CI] 69.9-87.6%), with specificity 71.9% (95% CI 63.7-79.2%). ABPI sensitivity was 80.2% (95% CI 70.8-87.6%), with specificity 88.6% (95% CI 82-93.5%). With comparable sensitivity to ABPI, MPPG is quick, automated and simpler to do than ABPI; it offers the potential for rapid and accessible PAD assessments in primary care.

The assessment of lower extremity peripheral artery disease impact on body mass center disorders.

BACKGROUND: Lower extremity peripheral artery disease is a problem of contemporary medicine and along with the ischemic heart disease it is considered to be a civilization disease. The risk of the disease increases significantly within a group of people reaching the age of 55 years and is closely related to co-occurring hazardous factors, such as diabetes, hyperlipidemia, hypertension or tobacco smoking. The first symptom reported by patients is intermittent claudication. Such symptoms may indicate that lower extremity peripheral artery disease does have an impact on posture disorders and motor skills. METHODS: The study covered four stages. The first stage involved medical interviews to obtain information regarding anthropometry, age, motor organ surgery, concomitant diseases and the lifestyle. In the following stage the value of the ankle brachial index for both lower limbs were calculated. In case of symptomatic patients, additionally, the location of artery stenosis/aortoiliac section, was verified. The third stage involved using a dynamometric platform for determination of the body mass center position for both studied groups. In the fourth stage a treadmill walk test was used to assess the participants for intermittent claudication. FINDINGS: Based on the obtained results, an attempt was taken to observe the relationship between the clinical characteristics of the disease and the body mass center position deviations. INTERPRETATION: The attempt was undertaken to assess whether the measurement of body mass center position might be a diagnostic parameter to evaluate the patient's condition and thus an indication for taking a decision for surgical treatment or rehabilitation.

Risk assessment indicators and brachial-ankle pulse wave velocity to predict atherosclerotic cardiovascular disease.

Brachial-ankle pulse wave velocity (baPWV) is used for predicting the severity of vascular damage and prognosis of atherosclerotic cardiovascular disease (ASCVD) in people with hypertension and diabetes mellitus. This correlation study aimed to compare the baPWV with other risk indicators for identification of subclinical vascular disease for primary prevention and to determine the clinical utility of baPWV-guided therapy in improving prognosis in high-risk subjects. We included 4881 subjects who underwent voluntary health examination at Mackay Memorial Hospital, Taiwan between 2014 and 2019. Participants were categorized into the low-risk (<5%), borderline-risk (5%-7.4%), intermediate-risk (7.5%-19.9%), and high-risk (≥20%) groups based on the 10-year risk for ASCVD. The predictive risk criteria, that is, the metabolic syndrome score, Framingham Risk Score, estimated glomerular filtration rate, and baPWV were compared among these groups. The chief cause of induced responses and the relationships between parameters were identified using principal component analysis. The participants' ages, body mass index, systolic, diastolic blood pressure, triglycerides, fasting glucose, hemoglobin A1c, creatinine, neutrophil-to-lymphocyte ratio, monocyte-to-lymphocyte ratio, metabolic syndrome, Framingham Risk Score, and age-related arterial stiffness (vascular age) increased significantly from the low-risk to high-risk groups (P < .001). The mean estimated glomerular filtration rate decreased significantly from the low- to high-risk groups (P < .001). The predicted vascular age and actual age differed significantly between the intermediate- and high-risk groups (P < .001). High-density lipoprotein levels plummeted significantly among the 4 groups (P < .001). The right and left baPWV and ankle brachial index differed significantly among the 4 groups (all P < .001) and increased from the low-risk to high-risk groups (P < .001). Carotid Doppler ultrasonography revealed a significant increase in plaque formation (23.5%, 35.4%, 46.3%, and 61.5% for the low-, borderline-, intermediate, and high-risk groups, respectively). The total explanatory variation was 61.9% for 2 principal variation factors (baPWV, 36.8% and creatinine, 25.1%). The vascular age predicted using baPWV greatly exceeded the chronological age. Plaque formation was significant even in the low-risk group, and its frequency increased with the predicted ASCVD risk. Risk indicators and baPWV are useful predictors of ASCVD, which in conjunction with conventional pharmacotherapy could be useful for primary prevention of plaque formation in subjects with cardiovascular comorbidities.

Ankle-Brachial Index for the Assessment of Peripheral Arterial Disease in the Emergency Department.

Peripheral arterial disease, both acute and chronic ischemia, is a clinical diagnosis encountered in the emergency department setting. The emergency nurse practitioner should be able to recognize the clinical presentation, understand the diagnostic tools available to make an appropriate clinical diagnosis, and know how to coordinate the appropriate treatment plan with a vascular surgeon. Timely and appropriate diagnosis of limb-threatening arterial disease is imperative to restore arterial perfusion and prevent the loss of the lower extremity.

The Association Between Socioeconomic Factors and Incident Peripheral Artery Disease in the Chronic Renal Insufficiency Cohort (CRIC).

BACKGROUND: The association between socioeconomic factors and development of peripheral artery disease (PAD) has not been as well characterized compared to other cardiovascular diseases. We sought to define how annual income, sex, race, and education level are associated with newly diagnosed PAD in a well-characterized, diverse set of adults with CKD. METHODS: The Chronic Renal Insufficiency Cohort Study (CRIC) is a multicenter, prospective cohort study designed to examine risk factors for progression of CKD and cardiovascular disease. Demographic and clinical data including ankle brachial index (ABI) and interventions were collected at baseline, as well as yearly during follow-up visits. Annual income was categorized as: <$25,000, $25,000-50,000, $50,000-100,000, or above $100,000. We excluded those with pre-existing PAD, defined as enrollment ABI of <0.9 or >1.4, or missing income data. Cox proportional hazards regression was used to estimate the risk for incident PAD during CRIC enrollment, defined as a drop in ABI to <0.90 or a confirmed PAD intervention, including revascularization or amputation. RESULTS: A total of 3,313 patients met inclusion criteria, the mean age was 58.7 years, 56% were male, and 42% were Black. Over a median follow-up of 10.1 years, 639 participants (19%) were newly diagnosed with PAD. After adjusting for cardiovascular risk factors, all lower levels of annual household income were associated with increased incidence of PAD (income <$25,000 HR 1.7, 95% CI 1.1-2.4, P = 0.008; income $25,000-50,000 HR 1.5, 95% CI 1.1-2.3, P = 0.009; income $50,000-100,000 HR 1.6, 95% CI 1.2-2.4, P = 0.004), relative to a baseline annual income of >$100,000 (overall P-value = 0.02). In the multivariable model, there was no association between education level and PAD incidence (P = 0.80). Black race (HR 1.2, 95% CI 1.0-1.5, P = 0.023) and female sex (HR 1.7, 95% CI 1.4-2.0, P < 0.001) were independently associated with PAD incidence. Multiple imputation analysis provided similar results. CONCLUSIONS: In the CRIC, a multi-center cohort of prospectively followed CKD patients undergoing yearly CVD surveillance, lower annual household income, female sex, and Black race were significantly associated with the PAD incidence. In contrast, level of education was not independently associated with incident PAD.

Peripheral Arterial Disease Located in the Feet of Patients With Diabetes and Foot Ulceration Demands a New Approach to the Assessment of Ischemia.

Peripheral arterial disease (PAD) is common below the knee in diabetes but arteries in the foot are controversially said to be spared of occlusive disease. This is relevant to the convenient site of vascular assessment that is recommended in guidelines. Should assessment be distal at toe/forefoot to detect foot disease or only proximal to detect disease at ankle level? The objective was to determine frequency of PAD at foot and ankle level. This was a cross-sectional observational study, evaluating arterial disease proximally by palpation of pedal pulses and Ankle Brachial Index (ABI), and distally by Toe Brachial Index (TBI), and forefoot transcutaneous oxygen tension (tcpO2), in consecutive patients presenting with foot ulceration. We assessed 301 limbs in 154 patients: 59% of limbs were ulcerated. PAD in the foot was detected in 70% and 74% of limbs by TBI and forefoot tcpO2, respectively, but PAD at ankle level only in 51% and 34% by pulse palpation and ABI, respectively. In limbs with "normal" ABI, PAD was present in the foot in 70% as indicated by low TBI, and in 73% by low tcpO2, with 70% to 64% having associated ulceration, respectively. When compared with arterial waveforms, as a measure of PAD, TBI gave an excellent AUC (area under the curve of the receiver operating characteristic curve) of 0.81 (95% confidence interval: 0.73-0.89), but ABI gave a poor AUC of 0.65 (95% confidence interval: 0.55-0.76). In conclusion, arterial disease is important in the foot and can be detected by TBI, which should be performed even when ABI is normal. Guidelines that recommend TBI only if ABI is artificially raised need updating.

3D Echocardiography - A Useful Method for Cardiovascular Risk Assessment in End-Stage Renal Disease Patients.

Patients with chronic kidney disease (CKD) have an increased risk of premature mortality, mainly due to cardiovascular causes. The association between hemodialysis and accelerated atherosclerosis has long been described. The ankle-brachial index (ABI) is a surrogate marker of atherosclerosis and recent studies indicate its utility as a predictor of future cardiovascular disease and all-cause mortality. The clinical implications of ABI cut-points are not well defined in patients with CKD. Echocardiography is the most widely used imaging method for cardiac evaluation. Structural and functional myocardial abnormalities are common in patients with CKD due to pressure and volume overload as well as non-hemodynamic factors associated with CKD. Our study aimed to identify markers of subclinical cardiovascular risk assessed using ABI and 2D and 3D echocardiographic parameters evaluating left ventricular (LV) structure and function in patients with end-stage renal disease (ESRD) (patients undergoing dialysis), patients after kidney transplantation and non-ESRD patients (control). In ESRD, particularly in hemodialysis patients, changes in cardiac structure, rather than function, seems to be more pronounced. 3D echocardiography appears to be more sensitive than 2D echocardiography in the assessment of myocardial structure and function in CKD patients. Particularly 3D derived end-diastolic volume and 3D derived LV mass indexed for body surface appears to deteriorate in dialyzed and transplanted patients. In 2D echocardiography, myocardial mass represented by left ventricular mass/body surface area index (LVMI) appears to be a more sensitive marker of cardiac structural changes, compared to relative wall thickness (RWT), left ventricle and diastolic diameter index (LVEDDI) and left atrial volume index (LAVI). We observed a generally favorable impact of kidney transplantation on cardiac structure and function; however, the differences were non-significant. The improvement seems to be more pronounced in cardiac function parameters, peak early diastolic velocity/average peak early diastolic velocity of mitral valve annulus (E/e´), 3D left ventricle ejection fraction (LV EF) and global longitudinal strain (GLS). We conclude that ABI is not an appropriate screening test to determine the cardiovascular risk in patients with ESRD.

Rationale and design of the application value of Beijing Vascular Health Stratification (BVHS): predictive value of combined assessment of vascular structure and function for cardiovascular events in general Chinese population.

BACKGROUND: Vascular endothelial dysfunction, arteriosclerosis and atherosclerotic plaque are well-known risk factors for cardiovascular disease (CVD). Studies on vascular health markers have been well-established, however, there is still a lack of related research on combined vascular structure and function indicators. METHOD: Beijing vascular health stratification (BVHS) is an evaluation system aiming at vascular health, combined the endothelial function, arteriosclerosis, atherosclerotic plaque and vascular lumen stenosis to comprehensively assess the vascular health and grade it. This study will explore the predictive value of the combined evaluation of vascular structure and function for cardiovascular events and assess the predictive value of BVHS and compare it with the existing risk assessment systems. A total of 1500 subjects will be enrolled into the prospective cohort study from a community and will be followed up for at least 3 years from July 1, 2020 to June 30, 2023. Subjects aged 40 or above, without coronary heart disease, stroke or peripheral artery disease, with written informed consent will be included; subjects with end-stage hepatorenal diseases (uremia, renal failure, cirrhosis, liver failure), mental disorders or cognitive disorders, with any other factors that the researcher thinks are not suitable for the study will be excluded. Traditional cardiovascular risk factors will be collected as adjusted confounders. DISCUSSION: BVHS is a potential and scientific vascular health evaluation system. The study will be the first to grade vascular health by combing various vascular indicators and explore the prediction value and compare with other risk prediction system in general Chinese population. TRIAL REGISTRATION: The trial is registered on http://www.chictr.org.cn/ (ChiCTR2000034085).

Assessment of toe brachial index validity in diabetic patients - interim results.

INTRODUCTION: The toe brachial index (TBI) is recommended for the detection of lower extremity arterial disease (LEAD) in case of reduced efficacy of the ankle brachial index (ABI), which most often occurs in diabetics. In this case, TBI is expected to give more accurate results. There are not many studies dealing with the use of TBI specifically in diabetics and the results are different. OBJECTIVE: The purpose of this work is to present the interim results of the study, whose main objective is to assess the validity of TBI in diabetics and to determine whether this method provides improvements over the ABI. METHODS: In the first phase of the study, 42 limbs were examined in 21 patients with type 2 diabetes. ABI was measured using the automatic oscillometric method (ABI OSC) and the manual method using the pencil doppler (ABI DPP). TBI was determined using an automatic plethysmographic method. The reference examination of the arteries of the lower limbs was performed using duplex ultrasonography (DUS). A paired t-test was used to compare the individual TBI and ABI methods. Cut-off points ABI < 0.9; TBI < 0.7; and DUS stenosis > 50 % were used to evaluate validity parameters. RESULTS: The individual ABI and TBI methods gave different results (p < 0.05). In eight limbs of the total number, LEAD was demonstrated using DUS. The best validity parameters were demonstrated by the TBI - sensitivity 0.88; specificity 0.88; positive predictive value 0.64; negative predictive value 0.97, positive likelihood ratio 7.44; negative likelihood ratio 0.14. The ABI method of calculation, that uses lower systolic blood pressure determined from two measurement sites on the ankle as a numerator, had a higher validity parameters. The ABI OSC did not correctly detect a single limb with stenosis > 50 % in this cohort. CONCLUSION: According to the interim results of this work, the TBI was more suitable for the detection of LEAD in diabetics in comparison with ABI.

Cost-effectiveness analysis of ankle-brachial index screening in patients with coronary artery disease to optimize medical management.

INTRODUCTION: Screening for peripheral artery disease (PAD) with the ankle-brachial index (ABI) test is currently not recommended in the general population; however, previous studies advocate screening in high-risk populations. Although providers may be hesitant to prescribe low-dose rivaroxaban to patients with coronary artery disease (CAD) alone, given the reduction in cardiovascular events and death associated with rivaroxaban, screening for PAD with the ABI test and accordingly prescribing rivaroxaban may provide additional benefits. We sought to describe the cost-effectiveness of screening for PAD in patients with CAD to optimize this high-risk populations' medical management. METHODS: We used a Markov model to evaluate the ABI test in patients with CAD. We assumed that all patients screened would be candidates for low-dose rivaroxaban. We assessed the cost of ABI screening at $100 per patient and added additional charges for physician visits ($100) and rivaroxaban cost ($470 per month). We used a 30-day cycle and performed analysis over 35 years. We evaluated quality-adjusted life years (QALYs) from previous studies and determined the incremental cost-effectiveness ratio (ICER) according to our model. We performed a deterministic and probabilistic sensitivity analyses of variables with uncertainty and reported them in a Tornado diagram showing the variables with the greatest effect on the ICER. RESULTS: Our model estimates decision costs to screen or not screen at $94,953 and $82,553, respectively. The QALYs gained from screening was 0.060, generating an ICER of $207,491 per QALY. Factors most influential on the ICER were the reduction in all-cause mortality associated with rivaroxaban and the prohibitively high cost of rivaroxaban. If rivaroxaban cost less than $95 per month, this would make screening cost-effective based on a willingness to pay threshold of $50,000 per QALY. CONCLUSIONS: According to our model, screening patients with CAD for PAD to start low-dose rivaroxaban is not currently cost-effective due to insufficient reduction in all-cause mortality and high medication costs. Nevertheless, vascular surgeons have a unique opportunity to prescribe or advocate for low-dose rivaroxaban in patients with PAD to improve cardiovascular outcomes.

Virtual ABI: A computationally derived ABI index for noninvasive assessment of femoro-popliteal bypass surgery outcome.

BACKGROUND AND OBJECTIVE: Peripheral arterial disease of the lower limbs, which affects 12-14% of the population, is often treated by bypassing a blocked portion of the vessel. Due to the limited ability of clinicians to predict the outcome of a selected bypass strategy, the five-year graft occlusion ranges from 50% to 90%, with a 20% risk of amputation in the first 5 years after the surgery. The aim of this study was to develop a computational procedure that could enable surgeons to reduce negative effects by assessing patient-specific response to the available surgical strategies. METHODS: The Virtual ABI assumes patient-specific finite element modeling of patients' hemodynamics from routinely acquired medical scans of lower limbs. The key contribution of this study is a novel approach for prescribing boundary conditions, which combines noninvasive preoperative measurements and results of numerical simulations. RESULTS: The validation performed on six follow-up cases indicated high reliability of the Virtual ABI, since the correlation with the experimentally measured values of ankle-brachial index was R² = 0.9485. CONCLUSION: The initial validation showed that the proposed Virtual ABI is a noninvasive procedure that could assist clinicians to find an optimal strategy for treating a particular patient by varying bypass length, choosing adequate diameter, position and shape.

Clinical Benefit, Harm, and Cost Effectiveness of Screening Men for Peripheral Artery Disease: A Markov Model Based on the VIVA Trial.

OBJECTIVE: Although screening for peripheral arterial disease (PAD) seems obvious due to its two to three times increased mortality, high prevalence in the elderly, ease of detection, and relatively harmless prevention, the evidence is sparse. METHODS: A Markov decision model was created to model the lifetime effectiveness and cost effectiveness of general population PAD screening and relevant intervention in 65 year old men. The model was informed by original estimates from the VIVA trial data except for ankle brachial systolic blood pressure index test accuracy, quality of life, and background mortality, which were adopted from the literature. A Markov model was designed for 65 year old men, who were distributed in the starting states of no/detected/undetected PAD. The main outcomes were life years, quality adjusted life years, and costs of healthcare. RESULTS: Screening for PAD reduced the rates of amputations and stroke by 10.9% and 2.4%, respectively, while it increased the rates of revascularisation, acute myocardial infarction, and major bleeding by 5.5%, 7.1%, and 4.3% respectively. The overall life expectancy was increased by 14 days per invited subject. The cost per life year/quality adjusted life year was estimated at €16 717/€20 673. On the addition of low dose rivaroxaban reduced the costs per life year gained by 40%. If the model ran for only five follow up years, screening reduced relative mortality by 1.71%, suggesting PAD screening accounts for one fourth of the reported overall 7% relative mortality risk reduction of combined abdominal aortic aneurysm, PAD, and hypertension screening. CONCLUSION: Screening of men for PAD is likely to be both clinically effective and cost effective in a lifetime perspective.