Peripheral arterial disease pathophysiology
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Peripheral arterial disease Microchapters |
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Differentiating Peripheral arterial disease from other Diseases |
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Diagnosis |
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Treatment |
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Case Studies |
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AHA/ACC Guidelines on Management of Lower Extremity PAD |
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Guidelines for Structured Exercise Therapy for Lower Extremity PAD |
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Guidelines for Minimizing Tissue Loss in Lower Extremity PAD |
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Guidelines for Revascularization of Claudication in Lower Extremity PAD |
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Guidelines for Management of Acute Limb Ischemial in Lower Extremity PAD |
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Guidelines for Longitudinal Follow-up for Lower Extremity PAD |
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Peripheral arterial disease pathophysiology On the Web |
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American Roentgen Ray Society Images of Peripheral arterial disease pathophysiology |
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Directions to Hospitals Treating Peripheral arterial disease |
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Risk calculators and risk factors for Peripheral arterial disease pathophysiology |
Editors-in-Chief: C. Michael Gibson, M.D., Beth Israel Deaconess Medical Center, Boston, MA; Robert G. Schwartz, M.D. [1], Piedmont Physical Medicine and Rehabilitation, P.A.; Associate Editor-In-Chief: Cafer Zorkun, M.D., Ph.D. [2]
Overview
Pathophysiology
- PAD is a manifestation of systemic atherosclerosis that has developed over many years.
- Atherosclerosis is a complex process that involves endothelial dysfunction, lipid disturbances, platelet activation, thrombosis, oxidative stress, vascular smooth muscle activation, altered matrix metabolism, remodeling and genetic factors
- Atherosclerosis frequently develops at arterial bifurcations and branches where endogenous atheroprotective mechanisms are impaired as a result of the effects of disturbed flow on endothelial cells
- The stages of atherosclerosis are divided into the following:
- Lesion initiation
- Results from endothelial dysfunction
- Formation of the fatty streak
- Results from an inflammatory lesion that develops first
- Affects the intima of the artery and leads to formation of the foam cell
- Fatty streak consists primarily of smooth muscle cells, monocytes, macrophages, and T and B cells
- Fibroproliferative atheroma development
- Originates from the fatty streak
- Contains larger numbers of smooth muscle cells frlled with lipids
- Advanced lesion development
- Results from continued accumulation of cells that make up the fatty streak and fibroproliferative atheroma
- Highly cellular
- Contains intrinsic vascular cell walls (both endothelial and smooth muscle), and inflammatory cells (monocytes, macrophages, and T lymphocytes)
- Also contains a lipid core covered by a fibrous cap
- Lesion initiation
- Arteries initially compensate for atherosclerosis by remodeling, which causes the blood vessels to increase in size
- Advanced lesions eventually intrude into the lumen, resultsing in flow-limiting stenoses and chronic ischemic syndromes
- Acute arterial events occur if the fibrous cap is disrupted, the resulting exposure of the "prothrombotic" necrotic lipid core and subendothelial tissue leads to thrombus formation and flow occlusion
- In addition to coronary artery disease and cerebrovascular disease, PAD is one of the three major syndromes of atherothrombosis
- Atherothrombosis is the term currently used to describe the process of thrombus formation on top of a ruptured plaque located at a disease arterial segment
- Such atherosclerotic plaques tend to occur at vessel bifurcations, presumed to be due to both impaired atheroprotective mechanisms and disturbed blood flow leading to local intimal injury
- Panvascular disease refers to clinically significant atherosclerosis is present in multiple vascular beds