Ankle-brachial Index Test Research Articles

Routine Ankle-Brachial Index (ABI) measurement: a window into atherosclerosis and early left ventricular dysfunction in patients diagnosed with cancer

BackgroundCancer therapy is considered to cause accelerated ischemia. Ankle-Brachial Index (ABI) measurement is an inexpensive, simple, available test for the early diagnosis of peripheral artery disease (PAD); however, it is not performed routinely. We aimed to evaluate the role of routine ABI measurement for the diagnosis of PAD among patients diagnosed with cancer and whether it correlates with left ventricular (LV) dysfunction.MethodsA retrospective, single-center study including patients diagnosed with cancer at Tel Aviv Sourasky Medical Center. The cohort included patients performing routine ABI and LV global longitudinal strain (GLS) echocardiography. The primary endpoint was the prevalence of PAD and whether it correlates with LV dysfunction, defined by LV GLS absolute value < 19%. The secondary composite endpoint evaluated the association between reduced ABI to LV dysfunction and all-cause mortality.ResultsAmong 226 patients, PAD was diagnosed in 14 patients (6%). We revealed a positive correlation between ABI and LV GLS (r = 0.22, p < 0.01) with a reduced mean ABI score among patients with reduced LV GLS. A reduced mean ABI was observed among the positive composite endpoint group; however, it was not statistically significant (p = 0.35).ConclusionsWe report, for the first time to our knowledge, the routine use of ABI testing among patients diagnosed with cancer. ABI showed a significant correlation to LV GLS, implying a potential tool in the early diagnosis of atherosclerosis and cardiotoxicity. Considering its low cost and availability, future prospective trials are needed to integrate its role in routine assessment.

Clinical efficacy of endovascular revascularization combined with vacuum-assisted closure for the treatment of diabetic foot.

The diabetic foot is a common cause of disability and death, and comorbid foot infections usually lead to prolonged hospitalization, high healthcare costs, and a significant increase in amputation rates. And most diabetic foot trauma is complicated by lower extremity arteriopathy, which becomes an independent risk factor for major amputation in diabetic foot patients. To establish the efficacy and safety of endovascular revascularization (ER) combined with vacuum-assisted closure (VAC) for the treatment of diabetic foot. Clinical data were collected from 40 patients with diabetic foot admitted to the Second Affiliated Hospital of Soochow University from April 2018 to April 2022. Diabetic foot lesions were graded according to Wagner's classification, and blood flow to the lower extremity was evaluated using the ankle-brachial index test and computerized tomography angiography of the lower extremity arteries. Continuous subcutaneous insulin infusion pumps were used to achieve glycemic control. Lower limb revascularization was facilitated by percutaneous tran-sluminal balloon angioplasty (BA) or stenting. Wounds were cleaned by nibbling debridement. Wound granulation tissue growth was induced by VAC, and wound repair was performed by skin grafting or skin flap transplantation. Of the 35 cases treated with lower limb revascularization, 34 were successful with a revascularization success rate of 97%. Of these, 6 cases underwent stenting after BA of the superficial femoral artery, and 1 received popliteal artery stent implantation. In the 25 cases treated with infrapopliteal artery revascularization, 39 arteries were reconstructed, 7 of which were treated by drug-coated BA and the remaining 32 with plain old BA. VAC was performed in 32 wounds. Twenty-four cases of skin grafting and 2 cases of skin flap transplantation were performed. Two patients underwent major amputations, whereas 17 had minor amputations, accounting for a success limb salvage rate of 95%. ER in combination with VAC is a safe and effective treatment for diabetic foot that can significantly improve limb salvage rates. The use of VAC after ER simplifies and facilitates wound repair.

Comparison of Postexercise Ankle Brachial Index in at Risk versus Diagnosed Peripheral Arterial Disease Population

Abstract Background: Peripheral arterial disease (PAD) is characterized by stenosis or occlusion in the arteries of the limb causing limitation in the distal blood flow. Out of the various risk factors identified, diabetes and cigarette smoking are the strongest predictors of PAD. PAD results from atherosclerosis of the vessel wall. Patients with lower extremity PAD have clinical presentation of intermittent claudication and atypical leg pain. In patients with arterial stenosis, there is a drop in pressure and flow across stenosis. Asymptomatic PAD approximately 20%–50% of total patients diagnosed with PAD. Ankle brachial index (ABI) is clinically widely used modality which helps to identify the disease. ABI test is the ratio of systolic ankle blood pressure and highest systolic brachial blood pressure. Population at risk with normal resting ABI may still have PAD. For such population, postexercise ABI is recommended. This study evaluated and compared ABI postexercise in normal healthy individuals without risk of PAD, at risk of PAD. Materials and Methods: This study is an observational study. Population with age more than 35 years were selected. Framingham Risk Score was taken for normal and at-risk population. Subjects were recruited in three groups: A, B, and C. ABI at rest was assessed. Individuals performed exercise treadmill test. Immediately, after completing the exercise, postexercise ABI was taken. Absolute systolic blood pressure values and postexercise ABI values were obtained in all three groups and then were compared. Data were analyzed using the SPSS software version 26. Results: The results of this study showed that for all the three groups, there was a significant difference in ABI at rest, postexercise ABI, and difference in systolic ankle pressure as P value was &lt;0.001. When the Chi-squared test was done for postexercise ABI and postsystolic ankle pressure in between Group B and Group C, there was no significant difference found as the P value was &gt;0.05. Conclusion: On comparison with at risk and normal individuals, no significant difference was found in terms of postexercise ABI and change in systolic ankle pressure.

Diagnostic accuracy of ankle-brachial index measurement in peripheral Arterial disease in TurkishAdults: A comparison with angiography

Objective: This study aims to assess the sensitivity and specificity of ankle-brachial index (ABI) measurements in diagnosing peripheral artery disease (PAD) among a cohort of Turkish subjects, with angiography serving as the reference standard. Material and Methods: In this single-center, cross-sectional and observational study, subjects who had an aorta and lower extremity arterial imaging by angiography subsequently underwent an ABI measurement. Anthropometric measurements, cardiovascular risk factors, and blood biochemistry data were recorded. Sensitivity and specificity analyses were performed for a low ankle-brachial index (ABI ≤ 0.9), with angiography as the reference standard. Results: A total of 57 patients (age: 59.1±15.9, male/female: 47/10) were included. Diabetes mellitus, coronary artery disease and cerebrovascular disease were present in 40.4%, 42.1% and 15.8% of the participants, respectively. Three or more cardiovascular risk factors were present in 54.4%. The angiographic diagnostic method was computed tomography angiography in 57.9%, digital subtraction angiography in 38.6%, and magnetic resonance angiography in 3.5% of the subjects. The presence of PAD on angiography was documented in 55 of 57 participants. The calculated mean ABI value was 0.6±0.2 in the overall group, and a low ABI (≤0.9) was found by 82.5% (n = 47). Compared to angiography, the low ankle-brachial index (ABI) test demonstrated a sensitivity of 83.6% and a specificity of 50%. The positive predictive value of 97.9% was calculated. When an ABI≤0.95 was used as the diagnostic threshold, the sensitivity of the ABI test increased to 90.9%. Conclusion: Our study confirms the reliability of ABI measurements as a diagnostic method for lower extremity peripheral artery disease (PAD) when compared to angiographic techniques, the gold standard. Establishing a higher cut-off value (≤0.95) may enhance the diagnostic performance of the test in Turkish patients.

Tibiofemoral Dislocation Management in a Rural High School Football Scenario: Development of a Popliteal Artery Injury Suspicion Index.

This study evaluated the knowledge and preparedness of athletic trainers (ATs) for diagnosing and managing an anterior tibiofemoral knee dislocation in a rural or limited-resource high school football setting scenario. The study hypothesis was that more experienced ATs would display greater preparedness than less experienced ATs. A secondary objective was to develop evidence-based guidelines to help the AT provide better emergency triage care. This prospective cross-sectional study distributed a rural high school football game scenario survey electronically to a random sample of 2000 certified ATs to determine their perceptions of readiness to diagnose and manage an anterior tibiofemoral knee dislocation with signs or symptoms of possible popliteal artery injury. A total of 249 surveys (12.5%) were completed. Years of athletic training experience were ≤5 years (n = 82, group 1) and ≥6 years (n = 167, group 2). Both groups perceived that they could not "rule out" an arterial injury and had similar "red flag" sign and symptom rankings. Group 2 perceived a more serious situation than group 1 (77.5 ± 15 vs 70.8 ± 14, P < 0.0001) and were more likely to activate the emergency action plan (74.5 ± 25 vs 64.4 ± 26, P = 0.005). Both groups were "neutral" about their ability to diagnose the condition or manage the case, had poor ankle-brachial index test familiarity, and agreed that evidence-based guidance was needed. More experienced ATs perceived a more serious situation than less experienced ATs and were more likely to activate the emergency action plan. Both groups were neutral about their ability to diagnose the condition or manage the case, had poor ankle-brachial index test familiarity, and agreed that they would benefit from evidence-based guidance. Proposed guidelines provide the AT with a more measured, evidence-based index of suspicion for potential popliteal artery injury in anterior tibiofemoral dislocation cases. This will complement existing hospital emergency department-based management algorithms, decreasing the likelihood of this condition progressing to limb loss or death.

Abstract 17200: PAD Raising Awareness in Sacred Environments “Praise”

Introduction: Atherosclerotic peripheral artery disease (PAD) leads to a great burden of cardiovascular and limb-related morbidity and mortality in African Americans (AA) compared to White Americans. Medical center partnerships with churches may be an effective method to improve PAD awareness and detection in the AA community. Hypotheses: We hypothesized that implementing a medical educational program in partnership with churches would increase PAD familiarity and identify participants with undiagnosed PAD. Aims: To determine (1) PAD familiarity before and after a one-time educational intervention and (2) the prevalence of PAD in older, church-going Nashville residents. Methods: Using a community-engaged research (CER) model, we partnered with 5 churches to enroll participants ≥ 50 years of age. Participants were given a 16-point pre- and post-educational program assessment to determine baseline and post-intervention PAD knowledge. Pre- and post-intervention scores were compared using Wilcoxon signed-rank test. Ankle-brachial index (ABI) testing was used to screen for PAD (ABI &lt; 0.9). Results: We enrolled 120 participants (mean age [SD]: 64.67 [8.33] years, 74% women, 80% AA). The prevalence of PAD was 10.83%. Pre-intervention PAD awareness was low (mean score (MS): 10.89 [4.24]) and improved significantly post-intervention in all participants (MS: 13.88 [2.76; p=2 x 10 -12 ). Participants without PAD (ABI ≥ 0.9-1.39) (MS: 10.81 [4.28] vs. 13.91 [2.79]; p= p=4 x 10 -11 ) and with indeterminate status (ABI&gt;1.4) (MS [SD]: 10.00 [5.03] vs. 14.10 [1.73; p=0.01) showed significant improvement in PAD awareness pre vs post intervention. Participants with PAD (ABI &lt;0.9) (MS: 12.15 [3.26] vs. 13.46 [3.26; p=0.40) did not have significant improvement in their awareness scores. Conclusions: The PRAISE study demonstrates an effective CER partnership with churches as a method to increase PAD awareness and early detection of PAD, specifically among AAs.

Адаптационные, регуляторные и функциональные возможности студентов с разным биологическим возрастом по шкале «Bio-age»

Biological age (BA) is determined by a set of metabolic, structural, functional, regulatory and adaptive characteristics of the body. Assessment of biological age is the key to studying the influence of time and environmental conditions on changes in the body at all stages of ontogenesis. The purpose of this article was to study the adaptive, regulatory and functional characteristics of students of different biological ages, determined using the Bio-Age scale. Materials and methods. The research involved 521 students aged 18–25 years who were examined at the Health Centre based at Arzamas City Hospital No. 1. These included anthropometry, bioelectrical impedance analysis, cardiointervalography, anklebrachial index test, as well as determination of total cholesterol and glucose levels in the blood. Results. Biological age assessment using the Bio-Age scale showed that only in 1/2 of the students the biological age coincides with the chronological age, while 1/3 of the subjects already have an accelerated rate of ageing. The adaptive capabilities of students whose biological age is less than the chronological age (BA &lt; CA) are better than of those whose biological age exceeds the chronological age (BA &gt; CA). This is confirmed not only by the adaptation degree according to R.M. Baevsky’s method, but also by stress index dynamics and by the parameters of heart rate spectral analysis. In students with BA &lt; CA, the functional state of the body is optimal both at rest and during an orthostatic test: the total power of the cardiointervalogram spectrum decreases due to reduced activity of the parasympathetic division. In students with BA &gt; CA, both in the supine and prone positions, a mismatch in the functioning of different parts of the autonomic nervous system was identified, namely, greater involvement of the central parts of heart rate control, increased sympathetic influences and a weaker activity of the parasympathetic division of the autonomic nervous system.

Performance of systolic pressure index for lower limb peripheral arterial disease in a group of elderly in sub-Saharan Africa

BackgroundThe automatic measurement of the ankle-brachial index (ABI) constitutes a reliable, simple, safe, rapid, and inexpensive alternative diagnostic screening test compared with the Doppler method for peripheral arterial disease (PAD). We aimed to compare the diagnostic performance of automatic ABI measurement tests to Doppler ultrasound for PAD in a group of patients aged 65 years and above, in Sub-Saharan Africa. MethodsThis was an experimental comparative study of the performance of Doppler ultrasound to the automated ABI test in the diagnosis of PAD in patients aged ≥ 65 years followed-up at the Yaoundé Central Hospital, Cameroon between January to June 2018. An ABI threshold < 0.90 is defined as a PAD. We compare the sensitivity, and specificity of the high ankle-brachial index (ABI-HIGH), low ankle-brachial index (ABI-LOW), and the mean ankle-brachial index (ABI-MEAN) for both tests. ResultsWe included 137 subjects with an average age of 71.7 ± 6.8 years. In the ABI-HIGH mode, the automatic device had a sensitivity of 55% and a specificity of 98.35% with a difference between the two techniques of d = 0.024 (p = 0.016). In the ABI-MEAN mode, it had a sensitivity of 40.63% and a specificity of 99.15%; d = 0.071 (p < 0.0001). In the ABI-LOW mode, it had a sensitivity of 30.95% and a specificity of 99.11%; d = 0.119 (p < 0.0001). ConclusionThe Automatic measurement of systolic pressure index has a better diagnostic performance in the detection of Peripheral Arterial Disease compared to the reference method by continuous Doppler in sub-Saharan African subjects aged ≥ 65 years.

Magnetic Resonance Imaging-Derived Microvascular Perfusion Modeling to Assess Peripheral Artery Disease.

Background Computational fluid dynamics has shown good agreement with contrast-enhanced magnetic resonance imaging measurements in cardiovascular disease applications. We have developed a biomechanical model of microvascular perfusion using contrast-enhanced magnetic resonance imaging signal intensities derived from skeletal calf muscles to study peripheral artery disease (PAD). Methods and Results The computational microvascular model was used to study skeletal calf muscle perfusion in 56 individuals (36 patients with PAD, 20 matched controls). The recruited participants underwent contrast-enhanced magnetic resonance imaging and ankle-brachial index testing at rest and after 6-minute treadmill walking. We have determined associations of microvascular model parameters including the transfer rate constant, a measure of vascular leakiness; the interstitial permeability to fluid flow which reflects the permeability of the microvasculature; porosity, a measure of the fraction of the extracellular space; the outflow filtration coefficient; and the microvascular pressure with known markers of patients with PAD. Transfer rate constant, interstitial permeability to fluid flow, and microvascular pressure were higher, whereas porosity and outflow filtration coefficient were lower in patients with PAD than those in matched controls (all P values ≤0.014). In pooled analyses of all participants, the model parameters (transfer rate constant, interstitial permeability to fluid flow, porosity, outflow filtration coefficient, microvascular pressure) were significantly associated with the resting and exercise ankle-brachial indexes, claudication onset time, and peak walking time (all P values ≤0.013). Among patients with PAD, interstitial permeability to fluid flow, and microvascular pressure were higher, while porosity and outflow filtration coefficient were lower in treadmill noncompleters compared with treadmill completers (all P values ≤0.001). Conclusions Computational microvascular model parameters differed significantly between patients with PAD and matched controls. Thus, computational microvascular modeling could be of interest in studying lower extremity ischemia.

New Approach to Measuring the Ankle and Toe Brachial Indices as New Markers for Early Detection of Lower Extremity Peripheral Artery Disease

Background: Lower extremity Peripheral artery disease (PAD) is caused by atherosclerosis, or Plaque buildup, that reduces the blood flow to the legs and feet. PAD affects approximately 230 million adults worldwide and is associated with an increased risk of coronary heart disease, stroke, and leg amputation. The first-line method for diagnosis of PAD is the Ankle Brachial Index (ABI), which is the ratio of ankle to brachial higher systolic pressure measured in ankles and arms. The Toe Brachial Index (TBI), which is the ratio of the toe systolic pressure to brachial higher systolic pressure measured in both arms, is considered to be an alternative to the ABI in screening for PAD. The ABI and TBI are measured on the right and left side, and the lower of these numbers is the patient’s overall ABI and TBI. Clinical studies and meta-analysis reviews have shown that the conventional ABI measurement, which uses a cuff, and handheld sphygmomanometer and continuous-wave Doppler tracings, provides an acceptable-to-high specificity level but low sensitivity when compared with vascular color Doppler ultrasound, and/or angiography methods. Another study has shown that the TBI measurement has greater sensitivity but lower specificity than the ABI when compared with vascular color Doppler ultrasound diagnostic based on waveforms. The aim of this clinical study was to evaluate the specificity and sensitivity of the VasoPad System comparing its results to the vascular color doppler ultrasound waveforms. Materials and Methods: The VasoPad System is an automated device using the pulse wave method to measure the arms and ankles dorsalis and tibial posterior artery blood pressures, the photoplethysmography second derivative (PTGSD) to estimate the toe systolic pressure, a patented photoplethysmography (PTG) index marker and volume plethysmography via cuffs during deflation. Vascular Color Doppler ultrasound can diagnose stenosis through the direct visualization of atherosclerosis or plaques and through waveform analysis. The vascular color Doppler ultrasound provides 3 waveform types. The type 1, triphasic waveform is normal blood flow and no atherosclerosis or plaque, the type 2, diphasic waveform is seen when there are atherosclerosis plaques, but normal blood flow, and the type 3, monophasic waveform reflects stenosis with diameter reduction > 50%. Results: The sum of the overall ABI and TBI VasoPad values, called Sum of Brachial Indices (SBI), gave a specificity of 88.89% and sensitivity of 100% for detecting vascular color Doppler ultrasound biphasic and monophasic waveforms versus triphasic waveforms with a cutoff ≤ 1.36 (P 50% (Doppler monophasic waveforms) but also early stage of atherosclerosis plaque of the lower extremities (Doppler biphasic waveforms). The VasoPad method provided a remarkable sensitivity of 100% and a specificity level similar to those of the conventional ABI test method compared with the vascular color Doppler ultrasound. In addition to being useful to screen and detect PAD, the VasoPad offers early detection of lower extremity atherosclerosis, with normal blood flow (Doppler biphasic waveforms), which could provide greater treatment options and thus reduce the overall number of lower extremity complications.

Provider ankle brachial index and wound classification teaching as part of a comprehensive limb preservation outreach program

ObjectiveUtilization of evidence-based specialty guidelines is low in primary care settings. Early use of ankle-brachial index (ABI) testing and a validated wound classification system allows prompt referral of patients for specialty care. We implemented a program to teach providers ABI testing and the use of the Wound, Ischemia, and foot Infection (WIfI) classification tool. Here, we report program outcomes and provider perceptions. MethodsPhysicians and non-physicians from wound care centers, nursing and physician education programs, primary care offices, and federally qualified health centers were invited to participate in the educational program teaching ABI testing and the use of the WIfI tool. Pretest and posttest responses and intention to use content in the future were assessed with descriptive statistics. ResultsA total of 101 subjects completed the ABI module, and 84 indicated their occupation (59 physicians, 25 non-physicians). Seventy-nine subjects completed the WIfI module, and 89% indicated their occupation (50 physicians, 20 non-physicians). Physicians had lower pre-test knowledge scores for the ABI module than non-physicians (mean scores of 7.9 and 8.2, respectively). Both groups had improved knowledge scores on the post-test (physicians, 13.4; non-physicians, 13.8; P < .001). Non-physicians in practice longer than 10 years at wound care centers had the lowest baseline knowledge scores, whereas physicians in practice for over 10 years had the highest. In the ABI module, the largest knowledge gap included accurately calculating the ABI, followed by the correct use of the Doppler, and management of incompressible vessels. For the WIfI module, providers struggled to accurately score patients based on wound classification. The greatest barriers to the implementation of ABI testing were the availability of trained personnel, followed by limited time for testing. Barriers to the use of the WIfI tool for physicians included lack of time and national guideline support. For non-physicians, the most notable barrier was a lack of training. ConclusionsProvider understanding of ABI and WIfI tools are limited in wound care centers, primary care offices, and federally qualified health centers. Further barriers include a lack of training in the use of tools, limited potential for point-of-care testing reimbursement, and insufficient dissemination of WIfI guidelines. Such barriers discourage widespread adoption and result in delayed diagnosis of arterial insufficiency.

Anterior superior iliac spine distraction for severe and recalcitrant diabetic foot ulcers

PurposeThe study aimed to introduce anterior superior iliac spine distraction to treat severe and recalcitrant diabetic foot ulcers. For comparison, we also included another group of diabetic foot ulcers treated with proximal tibial cortex transverse distraction. MethodsFrom February 1998 to February 2020, 87 patients (87 feet) with severe and recalcitrant diabetic foot ulcers were treated. The mean age of patients at surgery was 64 years (range, 47 to 87 years). The severity of the narrowed artery was assessed using the ankle-brachial index test. For comparison, another group of 91 patients (91 diabetic foot ulcers) treated with proximal tibial cortex transverse distraction was included. ResultsThe mean preoperative ankle-brachial indexes of the two groups were 0.41±0.07 and 0.39±0.05 (OR 0.65 [95% CI -0.77 to 1.58]; P=0.62), respectively. The mean preoperative limb pain was 3.42±2.84 cm and 3.52±3.11 cm (OR 1.54 [95% CI -077 to 1.35]; P=0.083), respectively. At the 2-year follow-up visit, ulcers healed in 72 (83%) and 74 (81%) patients, respectively (P=0.188). The mean postoperative limb pain was 0.52±0.23 cm and 0.49±0.41 cm (OR 2.32 [95% CI -0.27 to 1.66]; P=0.078), respectively. Pin-site infection occurred in 2 patients and 8 patients (P=0.09), respectively. Ulcer recurrence occurred in 13 (15%) patients and 15 (16%) patients (P=0.205), respectively. ConclusionsAnterior superior iliac spine transverse distraction may be an effective alternative treatment for severe and recalcitrant diabetic foot ulcers. It may be associated with fewer distraction-site complications than proximal tibial cortex transverse distraction. Level of evidenceTherapeutic study, Level IIa.

Abstract 15085: Modest Reduction in Ankle-Brachial Index Measurements and Risk of Major Adverse Limb Events Among 133,373 Veterans

Introduction: Low resting ankle-brachial index (ABI) serves as a non-invasive biomarker of poor limb outcomes. Whether modest decrements in ABI translate into higher risks of major adverse limb events (MALE) are unclear, particularly among women and minorities, because prior studies are small or lack racial diversity and incident outcomes. Methods: We analyzed data from participants in the Veterans Affairs Birth Cohort, a prospective, longitudinal cohort of veterans born between 1945-1965 with no clinical history of PAD prior to ABI testing. Participants were enrolled on or after 1/1/2000 and followed through 12/31/2016. The exposure was resting ABI and the outcome was MALE defined as limb revascularization or amputation based on VA and Medicare ICD-9/10 and CPT codes. Cox proportional hazards models assessed the association between ABI and MALE among black and white men and women. Models were adjusted for demographics and PAD risk factors ( Figure Legend ). Results: The analysis included 23,733 black men, 1,257 black women, 96,220 white men, and 2,813 white women. There were 14,431 MALE events. Risk for MALE across the ABI spectrum followed a j-shaped distribution ( Figure ). Both low and high ABIs were associated with an increased risk of MALE for black and white men and women ( Figure ). When we analyzed each sex/race group separately, as compared to a normal ABI measurement (1.11-1.20), a modestly reduced ABI (0.81-0.90) was associated with a significantly increased risk of MALE: black men HR adj , 2.17; 95% CI, 1.67-2.80; black women HR adj , 3,24; 95% CI, 1.21-8.69; white men HR adj , 3.04; 95% CI, 2.68-3.46; white women HR adj , 4.56; 95% CI, 1.73-11.99. Conclusions: In a large, diverse cohort of people free of prior PAD, a modest reduction in ABI was associated with a greater than two-fold increased risk of MALE for all sex/race groups. Further studies are needed to better understand why MALE occurs in this patient population despite only mildly reduced limb perfusion.

Getting Ready for Wound Certification: Factors Impeding Wound Healing.

Getting Ready for Wound Certification: Factors Impeding Wound Healing.

Cost-effectiveness analysis of screening for peripheral artery disease in patients with coronary artery disease in China: A Markov model

BackgroundThe innovative pharmacological combination of low-dose rivaroxaban plus aspirin provides clinicians with an ideal opportunity to intensify the medical treatment of patients with coronary artery disease (CAD) and comorbid peripheral artery disease (PAD). We aimed to determine the cost-effectiveness of PAD screening using the ankle-brachial index (ABI) test in patients with CAD (with rivaroxaban administered if the PAD screening was positive) compared with no-screening strategy in China. MethodsA Markov decision model using a 1-month cycle was developed to simulate the 25-year effectiveness and cost of PAD screening on 75-year-old patients with CAD in China, evaluating the quality-adjusted life years (QALYs) and incremental cost-effectiveness ratio (ICER). One-way, two-way, and probabilistic sensitivity analyses were conducted to assess the impact of variations in the key parameters for ICERs. ResultsOur model found an incremental cost of RMB4,959 (US$740) and an incremental QALY of 0.054 after one-time ABI screening, leading to an ICER of RMB91,936 (US$13,717) per QALY gained over a 25-year period. The reduction in all-cause mortality related to rivaroxaban and its cost were the factors most affecting the ICER. The screening would become cost-effective by decreasing the monthly cost of rivaroxaban to RMB184.5 (US$27.5) or by using domestic-brand rivaroxaban according to the threshold of a willingness to pay RMB72,447 (US$10,809) per QALY gained. ConclusionsOur study demonstrated that ABI screening for PAD to decide on low-dose rivaroxaban administration was not cost-effective for patients with CAD in China. Nevertheless, policy-guided cost changes for domestic-brand rivaroxaban could easily resolve this issue.

Ankle Brachial Index and Wound Classification Teaching to Providers as Part of a Comprehensive Limb Preservation Outreach Program

The use of evidence-based specialty guidelines is low in primary care settings. However, the early use of ankle brachial index (ABI) testing and a validated wound classification system allows for the prompt referral of patients for specialty care. We implemented a program to teach providers ABI testing and the use of the WIfI (wound, ischemia, foot infection) classification tool. In the present report, we have described the program outcomes.

Implementing Venous Leg Ulcer Education and Clinical Decision Support: A Quality Improvement Project

BACKGROUND: Venous leg ulcers (VLU) require early identification and treatment to prevent further harm. Health care providers often fail to initiate evidenced-based VLU treatment promptly because of a lack of knowledge of VLU guidelines. PURPOSE: To improve early treatment for patients with VLUs presenting to outpatient clinic settings. METHODS: Plan-Do-Study-Act cycles were used for this quality improvement project. Virtual education and a comprehensive clinical decision support (CDS) order set were implemented. Outcome metrics included the rate of ankle-brachial index (ABI) testing, mechanical compression therapy, and home health service referrals for patients with VLUs. The frequency with which the CDS order set was used was also measured. RESULTS: Forty health care providers attended the virtual education sessions among 3 outpatient clinics. There was an increase in ankle-brachial index testing from pre (n = 7; 15.9%) to post (n = 10; 18.2%) (P = .796), but there was a decline in mechanical compression therapy from pre (n = 15; 34.1%) to post (n = 4; 7.3%) (P = .002) and home health service referrals from pre (n = 11; 25%) to post (n = 9; 16.4%) (P = .322). The CDS order set was used 9 times over 13 weeks. CONCLUSION: Future Plan-Do-Study-Act cycles will include completing in-person education and reducing the VLU CDS order set length. Future projects should consider these approaches when implementing evidence-based VLU guidelines.

Novel and robust auxiliary indicators to ankle-brachial index using multi-site pulse arrival time and detrended fluctuation analysis for peripheral arterial disease assessment

The ankle-brachial index (ABI) test is a common tool used for screening peripheral arterial disease (PAD), but its accuracy has been doubted especially in patients with incompressible arteries attributed to calcification. Advanced wearable sensing technologies have potential to offer novel solutions for PAD assessment. This study investigated several novel indicators using the Detrended Fluctuation Analysis (DFA) on beat-to-beat RR interval (RRI) and pulse arrival time (PAT) from the four limbs of 7 young healthy and 7 elderly PAD subjects in supine and sitting postures. The auxiliary value of these indicators in addition to ABI for PAD assessment was also studied using a binary logistic regression model. The results showed that the short-scale DFA coefficients (α1) of RRI, α1 of PATs of fingers and α1_ratio of PAT (the ratio of α1 of PAT between the ipsilateral finger and toe) in supine posture, were significantly different between the PAD and healthy groups (1.26 ± 0.24 vs 0.76 ± 0.21, 1.03 ± 0.30 vs 0.68 ± 0.19, and 0.84 ± 0.20 vs 1.42 ± 0.47, respectively, p < 0.05), and the α1 of RRI and α1_ratio of PAT were not significantly influenced by postural change. Moreover, using ABI together with the supine α1_ratio of PAT was more sensitive in detecting PAD (sensitivity = 92.9%) than ABI alone (78.6%) with the same specificity of 100%. The short-scale DFA coefficients of multi-site PAT in supine posture, which can be measured by wearable devices, is an auxiliary to ABI for detecting PAD.

Ankle-Brachial Index and Wound Classification Teaching to Providers as Part of a Comprehensive Limb Preservation Outreach Program

Dissemination and use of evidence-based specialty guidelines is frequently low in primary care settings. Early use of ankle-brachial index (ABI) testing and a validated wound classification system including ischemia allows prompt referral of patients for appropriate specialty care. We implemented a program to teach providers ABI testing and use of the Wound, Ischemia, and foot Infection (WIfI) classification tool. Here we report program outcomes and provider perceptions. Physicians and nonphysicians from local wound care centers, nursing and physician education programs, primary care offices, and federally qualified health centers were recruited to participate in two educational modules on ABI testing and use of the WIfI tool. Pretest and post-test responses and intention to use the content in the future were assessed using descriptive statistics. There were 101 participants who completed the pretest and post-test of the ABI module. 84 indicated their occupation (59 physicians, 25 nonphysicians). Seventy participants completed the WIfI module (50 physicians, 20 nonphysicians). Physicians had lower pretest knowledge scores of ABI and WIfI principles than nonphysicians (mean score, 7.9 and 8.2, respectively) (Table I). Both groups significantly increased their scores on the post-test (physicians = 13.4; nonphysicians = 13.8; P < .001). Nonphysicians in practice longer than 10 years who worked at wound care centers had the lowest baseline knowledge scores, whereas physicians in practice more than 10 years had the highest. In the ABI testing module, the largest knowledge gap for providers included how to accurately calculate the ABI based on measurements, followed by how to hold the Doppler, and management of patients with incompressible vessels (Table II). For the WIfI module, providers were unfamiliar with accurately scoring participants based on the wound stage. The greatest barriers to use of ABI testing were availability of trained personnel, followed by limited time to complete testing. Barriers to use of the WIfI tool for physicians included lack of time and national guideline support. For nonphysicians, the most notable barrier was a lack of adequately trained personnel. Both physician and nonphysician understanding of the ABI and WIfI tools is limited in wound care centers, primary care offices, and federally qualified health centers. Further barriers include lack of dedicated training in use of tools, limited potential for point of care ABI testing reimbursement, and insufficient dissemination of guidelines for use of the WIfI tool. Such barriers discourage widespread adoption in primary care settings, leading to delayed diagnosis of arterial insufficiency in patients with lower extremity wounds.Table IBaseline ankle-brachial index (ABI) knowledge based on years in practice and provider typeProvider typeYears in practice% ParticipantsPretest mean (standard deviation)Nonphysician1-3597.80 (3.26)4-10247.25 (2.06)>10176.67 (3.06)Physician1-3708.00 (2.23)4-1087.00 (5.00)>10229.44 (1.59) Open table in a new tab Table IIPretest questions with >60% incorrect answersQuestion% IncorrectA 62-year-old man is being seen to evaluate leg pain associated with walking. You obtain the following brachial and tibial vessel pressures (mm Hg). Right brachial = 128, Left brachial = 134, Right dorsalis pedal = 120, Right posterior tibial = 122, Left dorsalis pedal = 110, Left posterior tibial = 119 What is the ankle-brachial index for the right lower extremity?79%Which of these is the suggested Doppler angle for obtaining arterial Doppler signals?64%While performing the ankle brachial index test, a patient's highest arm pressure is 134 but the tibial pressure is raised to over 220 and the Doppler signal can still be heard. Given the high ankle pressure, which is the most appropriate next step?61% Open table in a new tab

Artificial intelligence for the evaluation of peripheral artery disease using arterial Doppler waveforms to predict abnormal ankle-brachial index.

Patients with peripheral artery disease (PAD) are at increased risk for major adverse limb and cardiac events including mortality. Developing screening tools capable of accurate PAD identification is a necessary first step for strategies of adverse outcome prevention. This study aimed to determine whether machine analysis of a resting Doppler waveform using deep neural networks can accurately identify patients with PAD. Consecutive patients (4/8/2015 - 12/31/2020) undergoing rest and postexercise ankle-brachial index (ABI) testing were included. Patients were randomly allocated to training, validation, and testing subsets (70%/15%/15%). Deep neural networks were trained on resting posterior tibial arterial Doppler waveforms to predict normal (> 0.9) or PAD (⩽ 0.9) using rest and postexercise ABI. A separate dataset of 151 patients who underwent testing during a period after the model had been created and validated (1/1/2021 - 3/31/2021) was used for secondary validation. Area under the receiver operating characteristic curves (AUC) were constructed to evaluate test performance. Among 11,748 total patients, 3432 patients met study criteria: 1941 with PAD (mean age 69 ± 12 years) and 1491 without PAD (64 ± 14 years). The predictive model with highest performance identified PAD with an AUC 0.94 (CI = 0.92-0.96), sensitivity 0.83, specificity 0.88, accuracy 0.85, and positive predictive value (PPV) 0.90. Results were similar for the validation dataset: AUC 0.94 (CI = 0.91-0.98), sensitivity 0.91, specificity 0.85, accuracy 0.89, and PPV 0.89 (postexercise ABI comparison). An artificial intelligence-enabled analysis of a resting Doppler arterial waveform permits identification of PAD at a clinically relevant performance level.