Peripheral Microvascular Resistance as a Predictor for Limb Salvage
Peripheral Arterial DiseaseSalvaging a threatened limb is the key therapeutic objective for patients with critical limb ischemia, and the achievement of limb salvage is an independent predictor of patient morbidity and mortality. Despite successful primary endovascular or surgical intervention, the corresponding symptoms of rest pain and/or non-healing ulceration in some patients may continue, and amputation in these patients is unavoidable. It is hypothesized that the functional integrity of the peripheral vascular microcirculation may be impaired in these patients. However, there are currently no techniques that allow direct quantification and visualization of the microcirculation due to the micro-vessel invisibility under angiography. In the coronary circulation, coronary flow reserve (CFR) indicates the capacity for maximal hyperemic blood flow and reveals impaired coronary microvascular function. Studies have shown the clinical significance of measuring microvascular resistance to predict myocardial salvage after myocardial infarction. The study will explore whether this concept of coronary flow reserve can be applied peripherally to patients with critical limb ischemia in order to determine whether measuring peripheral vascular flow reserve can determine the integrity of the microcirculation to predict limb salvage after endovascular intervention.
Evaluation of an Electronic Health Record-based Screening Tool for Peripheral Artery Disease
Peripheral Artery DiseasePeripheral Vascular DiseaseThis protocol represents a pilot randomized-controlled trial evaluating the effect of an electronic health record (EHR)-based peripheral artery disease (PAD) screening tool on rates of new non-invasive testing, diagnosis and treatment of PAD over a 6-month period. An EHR-based PAD screening tool will be applied to the Stanford EHR, which will generate a group of patients of varying risks of having undiagnosed PAD. Patients with the highest risk of having undiagnosed PAD will then be evaluated for inclusion in this study. 1:1 randomization will be performed on a consecutive basis until study enrollment is completed (25 patients per arm). Physicians of patients randomized to the intervention arm will be sent notification via an EHR message detailing the patient's risk of undiagnosed PAD and suggestions for referral to vascular medicine for risk assessment and/or non-invasive ankle brachial index (ABI) testing. The primary outcome is number of patients receiving ABI testing for PAD at 6 months, with secondary outcomes including number of new PAD diagnoses, number of new referrals to cardiovascular specialists (vascular medicine, vascular surgery, and/or cardiology) and number of patients receiving initiation of new cardiovascular medications (anti-platelet agents, statins, and/or antihypertensive agents).
AndraValvulotome Post-Market Study
Peripheral Arterial DiseaseThe AndraValvulotome Post-Market Study is a prospective, open-label, multi-center study to evaluate the efficacy and safety of the AndraValvulotome. A maximum of 70 patients will be enrolled with peripheral artery disease (PAD) in up to 10 sites. Study participants will be primarily observed during the bypass procedure. In addition, the patients will be re-evaluated at the follow-up visit which will be scheduled 30 +/- 7 days after beginning of the study participation. The objective of this study is to analyze the efficacy and safety of the valvulotomy of the venous valves with the CE marked AndraValvulotome during the bypass procedure.
N-Acetyl-Cysteine (NAC) for Healing of Amputation Stumps in the Setting of Diabetes
Diabetes MellitusCritical Limb Ischemia2 moreIn this pilot clinical study the investigators propose to conduct a prospective, randomized, double-blinded, placebo-controlled clinical trial for 30 days for participants with critical limb ischemia (CLI) who undergo a major (above-knee or below-knee) lower extremity amputation. By exploring the primary endpoints we aim to determine whether NAC can affect amputation stump perfusion and healing. Based on preclinical data, the investigators hypothesize that NAC will augment both amputation stump perfusion as well as healing. The investigators will utilize the data from this trial to determine the true effect size that is necessary for a larger clinical trial to determine the clinical efficacy of NAC is healing surgical sites such as major lower extremity amputation stumps.
Individual Patient Data Analysis of Viabahn for Peripheral Arterial Disease
Peripheral Vascular DiseasesTo evaluate the effectiveness of the VSX device in pre-determined patient populations to understand the patient characteristics that impact outcomes.
New Cardiovascular Risk Screening Strategy.
Cardiovascular PreventionScreening3 moreMortality due to cardiovascular disease (CVD) in Spain accounted for 29% of all deaths (32% in women and 26% in men) in 2017. Out of those, 67% were related to a coronary or a cerebrovascular disease . A key strategy in primary prevention of CVD is to use risk functions to individualize preventive interventions for each patient. The current CV risk-screening program in some regions of Spain, is based using an adapted Framingham scale, REGICOR's risk function, which is integrated in the primary care electronic health record. This risk function predicts the probability within 10 years of developing a coronary event. However, this function fails to identify patients that fall into low- or intermediate-risk level, and might develop a CV event in the up following 10 years. Ankle-brachial index (ABI) is a simple, non-invasive and economic technique, which allows detecting peripheral arterial disease (PAD), and gives independent risk function information compared to other coronary risk functions. Even tough, between 13-27% of middle age population have an ABI ≤ 9, around 50-89% of them do not exhibit any symptoms. However, they hold higher mortality risk and CV events. Current clinical guidelines for PAD screening, have a limited level of evidence, and only recommend using ABI on patients aged 50-70, who have diabetes or are smokers, and patients older than 70 years old. A new risk function, REASON, to assess CVD risk has been designed. This model has proven to improve predictive capacity of holding an ABI ≤ 0.9 on those patients aged 50-74 that are apparently free of CVD. Therefore, a strategy that combines the current CV risk estimation using REGICOR, and the prediction capacity of pathologic ABI with REASON, would allow detecting high-risk patients with a PAD screening program. It is possible that patients, who hold an ABI ≤ 0.9, even if being asymptomatic, will adopt physician's recommendations on healthy life habits and preventive treatment. The aims of this study are: To assess the effectiveness and cost-utility of adding a screening program with ABI to the current strategy of CV risk detection to reduce the incidence of CVD and mortality from all causes in the population aged 50 to 74. To assess the effectiveness of adding a screening program with ABI to the current strategy of CV risk detection to improve cardiovascular risk factors in the population aged 50 to 74.
The Intersectional Viborg Screening Program: Cost-(Effectiveness) of Screening for Diabetes and...
AgingAortic Aneurysm7 moreThis is an intersectional and interdisciplinary screening program in Viborg Municipality, including 67 years old citizens. This observational study will estimate the cost-effectiveness of a combined screening program for the following conditions: Abdominal aortic aneurysm, peripheral arterial disease, carotid plaque, hypertension, arrhythmia, and type-2-diabetes. Furthermore, the incidence of the outlined conditions will be described and so will the result of the intervention initiated (secondary medical prophylaxis, smoking cessation, introduction to nutritionally deficient diet etc.)
Prevalence of the Appearance of Diabetic Ulcers in Patients With 3D Insole and LSCI.
Diabete Type 2Diabetic Foot5 moreDiabetes is a serious and chronic disease that affects more than 347 million people in the world. It is the leading cause of death by age and its prevalence is increasing annually throughout the world. Diabetes is a disorder that manifests itself with elevated blood glucose levels that may be the resultof a deficiency in insulin secretion or action, or a combination of both problems. The "Diabetic foot" includes a number of syndromes in which the interaction of the loss of protective sensation by the presence of sensory neuropathy, the change in pressure points due to motor neuropathy, autonomic dysfunction and decreased Blood flow due to peripheral vascular disease can lead to the appearance of injuries or ulcers induced by minor traumas that go "unnoticed." This situation leads to significant morbidity and a high risk of amputation. It can be prevented with the application of prevention programs, based on the early detection of neuropathy, assessment of associated risk factors, along with the application of a structured program of education and treatment of risk factors. PRIMARY OBJECTIVES: 1- Comparison of ulceration rates, decrease in amputation rates in the target population with intervention: LSCI, thermography and creation of personalized insoles versus the control group with assessment, treatment and follow-up, without the intervention of interest in the study. 2- Correlation between changes in perfusion and temperature detected in combination of LSCI and thermography to predict diabetic foot ulcers and the risk of having ulcers. Study Model: Parallel Assignment 1:1 . Patients with inclusion criteria and without exclusion criteria will be randomized into two groups with Randomization with sequence concealment, centralized in computer support. OxMaR (Oxford Minimization and Randomization) After signing the informed consent, the patients will be divided into two groups. Number of Arms 2 Masking: None (Open Label) A-GROUP WITH LSCI, 3D FOOT CREATOR FOLLOW UP B- GROUP WITHOUT LSCI, 3D FOOT CREATOR FOLLOW UP.
Effects of Remote Ischemic Preconditioning on Restenosis Post Lower Limb Revascularization Angioplasty...
Peripheral Vascular DiseasesThe investigators will established relation between restenosis and inflammatory response to shearing stress caused by angioplasty suggest that any mechanism that affect inflammatory response can consequently affect the restenosis rate. There is accumulated evidence that remote ischemic precondition has modifying suppressive effect on inflammatory response and the investigators hypothesized that RIPC may lead to reduction in post angioplasty restenosis rate.
Outpatient Office Based Endovascular Procedures
Chronic Venous InsufficiencyPeripheral Arterial Disease5 moreThe results of this study will serve as a starting point for future trials concentrating on the effectiveness and clinical outcomes of the procedures performed in an office based angiosuite. Additionally, other studies could compare clinical outcomes between procedures performed in an office based angiosuite and other settings.