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European Journal of Vascular and... Jan 2004Digital ischemia in dialysis patients due to arteriovenous fistulas (AVF) is a rare condition, occurring in 4% of patients. The etiology is different from lower limb... (Review)
Review
Digital ischemia in dialysis patients due to arteriovenous fistulas (AVF) is a rare condition, occurring in 4% of patients. The etiology is different from lower limb ischemia. Blood shunting through the AVF may cause stealing of blood and hypoperfusion in distal tissues, leading to pain, discolorisation and ulcers. High-flow AVFs have greater risk on ischemia than normal flow AVFs, however combined with peripheral arteriosclerotic disease the latter may also leads to ischemia. A non-invasive and angiographic diagnosis is of importance to determine treatment options. Augmentation of arterial inflow by interventional techniques and/or AVF bloodflow-reducing surgical procedures may eliminate pain and heal ulcers. The best results are obtained by bypassing the arteriovenous anastomotic site and interruption of steal phenomenon by ligation of the artery distal to the AV anastomosis.
Topics: Angioplasty, Balloon; Arm; Arteriovenous Shunt, Surgical; Humans; Ischemia; Renal Dialysis; Vascular Surgical Procedures
PubMed: 14652830
DOI: 10.1016/j.ejvs.2003.10.007 -
Methods in Molecular Biology (Clifton,... 2018Therapeutic angiogenesis offers promise as a novel treatment that is complementary to surgical or endovascular procedures for peripheral arterial diseases (PAD).... (Review)
Review
Therapeutic angiogenesis offers promise as a novel treatment that is complementary to surgical or endovascular procedures for peripheral arterial diseases (PAD). Appropriate development and use of hind limb ischemia models is necessary for successful studies of therapeutic angiogenesis and/or arteriogenesis. In this chapter, we describe two commonly used murine unilateral hind limb ischemia models, the femoral artery transection model and the femoral/saphenous artery excision model.
Topics: Animals; Disease Models, Animal; Hindlimb; Humans; Ischemia; Mice; Neovascularization, Physiologic; Peripheral Arterial Disease
PubMed: 29468589
DOI: 10.1007/978-1-4939-7526-6_11 -
Arteriosclerosis, Thrombosis, and... Nov 2020This brief review summarizes current evidence regarding lower extremity peripheral artery disease (PAD) and lower extremity skeletal muscle pathology. Lower extremity... (Review)
Review
This brief review summarizes current evidence regarding lower extremity peripheral artery disease (PAD) and lower extremity skeletal muscle pathology. Lower extremity ischemia is associated with reduced calf skeletal muscle area and increased calf muscle fat infiltration and fibrosis on computed tomography or magnetic resonance imaging. Even within the same individual, the leg with more severe ischemia has more adverse calf muscle characteristics than the leg with less severe ischemia. More adverse computed tomography-measured calf muscle characteristics, such as reduced calf muscle density, are associated with higher rates of mobility loss in people with PAD. Calf muscle in people with PAD may also have reduced mitochondrial activity compared with those without PAD, although evidence is inconsistent. Muscle biopsy document increased oxidative stress in PAD. Reduced calf muscle perfusion, impaired mitochondrial activity, and smaller myofibers are associated with greater walking impairment in PAD. Preliminary evidence suggests that calf muscle pathology in PAD may be reversible. In a small uncontrolled trial, revascularization improved both the ankle-brachial index and mitochondrial activity, measured by calf muscle phosphocreatine recovery time. A pilot clinical trial showed that cocoa flavanols increased measures of myofiber health, mitochondrial activity, and capillary density while simultaneously improving 6-minute walk distance in PAD. Calf muscle pathological changes are associated with impaired walking performance in people with PAD, and interventions that both increase calf perfusion and improve calf muscle health are promising therapies to improve walking performance in PAD.
Topics: Animals; Energy Metabolism; Exercise Tolerance; Humans; Ischemia; Leg; Mitochondria, Muscle; Muscle, Skeletal; Oxidative Stress; Peripheral Arterial Disease; Prognosis; Regional Blood Flow; Walking
PubMed: 32938218
DOI: 10.1161/ATVBAHA.120.313831 -
European Journal of Vascular and... Dec 2011Ulcerated diabetic foot is a complex problem. Ischaemia, neuropathy and infection are the three pathological components that lead to diabetic foot complications, and... (Review)
Review
Ulcerated diabetic foot is a complex problem. Ischaemia, neuropathy and infection are the three pathological components that lead to diabetic foot complications, and they frequently occur together as an aetiologic triad. Neuropathy and ischaemia are the initiating factors, most often together as neuroischaemia, whereas infection is mostly a consequence. The role of peripheral arterial disease in diabetic foot has long been underestimated as typical ischaemic symptoms are less frequent in diabetics with ischaemia than in non-diabetics. Furthermore, the healing of a neuroischaemic ulcer is hampered by microvascular dysfunction. Therefore, the threshold for revascularising neuroischaemic ulcers should be lower than that for purely ischaemic ulcers. Previous guidelines have largely ignored these specific demands related to ulcerated neuroischaemic diabetic feet. Any diabetic foot ulcer should always be considered to have vascular impairment unless otherwise proven. Early referral, non-invasive vascular testing, imaging and intervention are crucial to improve diabetic foot ulcer healing and to prevent amputation. Timing is essential, as the window of opportunity to heal the ulcer and save the leg is easily missed. This chapter underlines the paucity of data on the best way to diagnose and treat these diabetic patients. Most of the studies dealing with neuroischaemic diabetic feet are not comparable in terms of patient populations, interventions or outcome. Therefore, there is an urgent need for a paradigm shift in diabetic foot care; that is, a new approach and classification of diabetics with vascular impairment in regard to clinical practice and research. A multidisciplinary approach needs to implemented systematically with a vascular surgeon as an integrated member. New strategies must be developed and implemented for diabetic foot patients with vascular impairment, to improve healing, to speed up healing rate and to avoid amputation, irrespective of the intervention technology chosen. Focused studies on the value of predictive tests, new treatment modalities as well as selective and targeted strategies are needed. As specific data on ulcerated neuroischaemic diabetic feet are scarce, recommendations are often of low grade.
Topics: Amputation, Surgical; Debridement; Diabetic Foot; Diabetic Neuropathies; Diagnostic Imaging; Humans; Ischemia; Peripheral Vascular Diseases; Practice Guidelines as Topic; Surgical Flaps; Vascular Surgical Procedures
PubMed: 22172474
DOI: 10.1016/S1078-5884(11)60012-9 -
European Journal of Vascular and... Dec 2011Non-invasive vascular studies can provide crucial information on the presence, location, and severity of critical limb ischaemia (CLI), as well as the initial assessment... (Review)
Review
Non-invasive vascular studies can provide crucial information on the presence, location, and severity of critical limb ischaemia (CLI), as well as the initial assessment or treatment planning. Ankle-brachial index with Doppler ultrasound, despite limitations in diabetic and end-stage renal failure patients, is the first-line evaluation of CLI. In this group of patients, toe-brachial index measurement may better establish the diagnosis. Other non-invasive measurements, such as segmental limb pressure, continuous-wave Doppler analysis and pulse volume recording, are of limited accuracy. Transcutaneous oxygen pressure (TcPO(2)) measurement may be of value when rest pain and ulcerations of the foot are present. Duplex ultrasound is the most important non-invasive tool in CLI patients combining haemodynamic evaluation with imaging modality. Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) are the next imaging studies in the algorithm for CLI. Both CTA and MRA have been proven effective in aiding the decision-making of clinicians and accurate planning of intervention. The data acquired with CTA and MRA can be manipulated in a multiplanar and 3D fashion and can offer exquisite detail. CTA results are generally equivalent to MRA, and both compare favourably with contrast angiography. The individual use of different imaging modalities depends on local availability, experience, and costs. Contrast angiography represents the gold standard, provides detailed information about arterial anatomy, and is recommended when revascularisation is needed.
Topics: Algorithms; Arterial Occlusive Diseases; Critical Illness; Decision Making; Diabetic Foot; Diagnostic Imaging; Hemodynamics; Humans; Ischemia; Lower Extremity; Peripheral Vascular Diseases; Risk Assessment; Sensitivity and Specificity
PubMed: 22172470
DOI: 10.1016/S1078-5884(11)60010-5 -
Journal of the American Heart... Feb 2016
Review
Topics: Cardiovascular Agents; Critical Illness; Diffusion of Innovation; Endovascular Procedures; Forecasting; Humans; Ischemia; Limb Salvage; Peripheral Arterial Disease; Secondary Prevention; Time Factors; Treatment Outcome; Vascular Surgical Procedures
PubMed: 26908409
DOI: 10.1161/JAHA.115.002938 -
Journal of Vascular Surgery Jun 2020Deep venous arterialization (DVA) is a technique aimed at providing an option for chronic limb-threatening ischemia patients with no options except amputation. In... (Review)
Review
OBJECTIVE
Deep venous arterialization (DVA) is a technique aimed at providing an option for chronic limb-threatening ischemia patients with no options except amputation. In patients with no outflow distal targets permitting bypass, DVA involves creating a connection between a proximal arterial inflow and a distal venous outflow in conjunction with disruption of the vein valves in the foot. This permits blood flow to reach the foot and potentially to resolve rest pain or to assist in healing of a chronic wound. We aimed to provide an up-to-date review of DVA indications; to describe the open, percutaneous, and hybrid technique; to detail outcomes of each of the available techniques; and to relay the postoperative considerations for the DVA approach.
METHODS
A literature review of relevant articles containing all permutations of the terms "deep venous arterialization" and "distal venous arterialization" was undertaken with the MEDLINE, Cochrane, and PubMed databases to find cases of open, percutaneous, and hybrid DVA in the peer-reviewed literature. The free text and Medical Subject Headings search terms included were "ischemia," "lower extremity," "venous arterialization," "arteriovenous reversal," and "lower limb salvage." Studies were primarily retrospective case series but did include two studies with matched controls. Recorded primary outcomes were patency, limb salvage, wound healing, amputation, and resolution of rest pain, with secondary outcomes of complication and overall mortality. Studies were excluded if there was insufficient discussion of technical details (graft type, target vein) or lack of reported outcome measure.
RESULTS
Studies that met inclusion criteria (12 open, 3 percutaneous, 2 hybrid) were identified, reviewed, and summarized to compare technique, patient selection, and outcomes between open, percutaneous, and hybrid DVA. For open procedures, 1-year primary patency ranged from 44.4% to 87.5%; secondary patency was less reported but ranged from 55.6% at 1 year to 72% at 25-month follow-up. Limb salvage rates ranged from 25% to 100%, wound healing occurred in 28.6% to 100% of cases, and rest pain resolved in 11.9% to 100% across cohorts. For the endovascular approach, primary patency ranged from 28.6% to 40% at 6-month and 10-month follow-up. Limb salvage rates ranged from 60% to 71%, with rates of major amputation ranging from 20% to 28.5%.
CONCLUSIONS
This review provides an up-to-date review of DVA indications, description of various DVA techniques, patient selection associated with each approach, and outcomes for each technique.
Topics: Amputation, Surgical; Chronic Disease; Foot; Humans; Ischemia; Limb Salvage; Peripheral Arterial Disease; Recovery of Function; Risk Factors; Time Factors; Treatment Outcome; Vascular Grafting; Vascular Patency; Wound Healing
PubMed: 31901360
DOI: 10.1016/j.jvs.2019.10.085 -
Tidsskrift For Den Norske Laegeforening... Apr 2005Arterial ischaemic ulcers develop because of inadequate perfusion leading to local ischaemia in the skin and underlying tissue. The most common cause is peripheral... (Review)
Review
Arterial ischaemic ulcers develop because of inadequate perfusion leading to local ischaemia in the skin and underlying tissue. The most common cause is peripheral arterial disease, giving rise to symptoms like intermittent claudication, rest pain and gangrene, in addition to local ulceration. Diabetes mellitus increases the risk of ulcer formation; admittedly mainly neuropathic ulcers with a low component of peripheral arterial disease. Yet a combination of neuropathy and ischaemia is common ("neuro-ischaemic ulcer"). A thorough patient history and clinical examination can help discriminate arterial ulcers from venous, pressure, traumatic and vasculitis ulcers. Reduction of ankle systolic pressure and calculated ankle/brachial index, sometimes additional other non-invasive laboratory tests, confirm peripheral arterial disease. The primary treatment of arterial ischaemic ulcer is to increase blood supply to the affected area, primarily by endovascular treatment or open arterial reconstruction. Endovascular treatment (balloon angioplasty) is the method of choice because of graft infection risk in patients with open ulcers. Most arterial ischaemic ulcers will progress to healing if the blood supply is reestablished.
Topics: Angioplasty, Balloon; Antihypertensive Agents; Arteries; Atmosphere Exposure Chambers; Blood Pressure Determination; Humans; Ischemia; Leg Ulcer; Vascular Surgical Procedures; Venous Insufficiency
PubMed: 15815738
DOI: No ID Found -
Cardiovascular Research Mar 2019Peripheral arterial disease (PAD) is the leading cause of lower limb amputation and estimated to affect over 202 million people worldwide. PAD is caused by... (Review)
Review
Peripheral arterial disease (PAD) is the leading cause of lower limb amputation and estimated to affect over 202 million people worldwide. PAD is caused by atherosclerotic lesions that occlude large arteries in the lower limbs, leading to insufficient blood perfusion of distal tissues. Given the severity of this clinical problem, there has been long-standing interest in both understanding how chronic arterial occlusions affect muscle tissue and vasculature and identifying therapeutic approaches capable of restoring tissue composition and vascular function to a healthy state. To date, the most widely utilized animal model for performing such studies has been the ischaemic mouse hindlimb. Despite not being a model of PAD per se, the ischaemic hindlimb model does recapitulate several key aspects of PAD. Further, it has served as a valuable platform upon which we have built much of our understanding of how chronic arterial occlusions affect muscle tissue composition, muscle regeneration and angiogenesis, and collateral arteriogenesis. Recently, there has been a global surge in research aimed at understanding how gene expression is regulated by epigenetic factors (i.e. non-coding RNAs, histone post-translational modifications, and DNA methylation). Thus, perhaps not unexpectedly, many recent studies have identified essential roles for epigenetic factors in regulating key responses to chronic arterial occlusion(s). In this review, we summarize the mechanisms of action of these epigenetic regulators and highlight several recent studies investigating the role of said regulators in the context of hindlimb ischaemia. In addition, we focus on how these recent advances in our understanding of the role of epigenetics in regulating responses to chronic arterial occlusion(s) can inform future therapeutic applications to promote revascularization and perfusion recovery in the setting of PAD.
Topics: Animals; Chronic Disease; Collateral Circulation; Disease Models, Animal; Epigenesis, Genetic; Hindlimb; Humans; Ischemia; Mice; Muscle, Skeletal; Neovascularization, Physiologic; Peripheral Arterial Disease; Rats; Regeneration; Regional Blood Flow
PubMed: 30629133
DOI: 10.1093/cvr/cvz001 -
Vascular and Endovascular Surgery Jul 2022Heavy cannabis use has been associated with the development of acute myocardial infarction and stroke. The objective of this study was to determine if heavy, chronic...
OBJECTIVES
Heavy cannabis use has been associated with the development of acute myocardial infarction and stroke. The objective of this study was to determine if heavy, chronic cannabis use is associated with the development of acute limb ischemia (ALI) or critical limb ischemia (CLI).
METHODS
We conducted a retrospective cohort study within the National Inpatient Sample (2006-2015). Patients without cannabis use disorder (CUD) were matched to patients with CUD in a 2:1 ratio using propensity scores. Our primary outcomes were incidence of ALI and CLI. Secondary outcomes included incidence of acute mesenteric ischemia (AMI), chronic mesenteric ischemia (CMI), frequency of open or endovascular interventions, length of stay, and total costs. Sensitivity analyses were performed with alternative models, including in the entire unmatched cohort with regression models utilizing survey weights to account for sampling methodology.
RESULTS
We identified a cohort of 46,297 857 unmatched patients. Patients with CUD in the unmatched cohort were younger, with less cardiovascular risk factors, but higher rates of smoking and substance abuse. The matched cohort included 824,856 patients with CUD and 1,610,497 controls. Those with CUD had a higher incidence of ALI (OR 1.20 95% CI: 1.04-1.38 =.016). Following multiple sensitivity analyses, there was no robust association between CLI and CUD. We observed no robust association of CUD with AMI, CMI, procedures performed, frequency of amputation, costs, or total length of stay.
CONCLUSIONS
Cannabis use disorder was associated with a significantly higher incidence of admission for acute limb ischemia. CUD was not associated with an increased risk of critical limb ischemia following sensitivity analysis. Given CUD is often seen in younger, less co-morbid patients it provides an important target for intervention in this population.
Topics: Amputation, Surgical; Arterial Occlusive Diseases; Chronic Limb-Threatening Ischemia; Endovascular Procedures; Humans; Ischemia; Limb Salvage; Marijuana Abuse; Mesenteric Ischemia; Peripheral Arterial Disease; Retrospective Studies; Risk Factors; Time Factors; Treatment Outcome
PubMed: 35503434
DOI: 10.1177/15385744221085382