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Treatment is often in the form of preventative measures of prophylaxis. Drug therapy for underlying conditions, such as drugs for the treatment of high cholesterol, drugs to treat high blood pressure (ACE inhibitors), and anti-coagulant drugs, are often prescribed to help prevent arteriosclerosis. Lifestyle changes such as increasing exercise, stopping smoking, and moderating alcohol intake are also advised. Experimental treatments include senolytic drugs, or drugs that selectively eliminate senescent cells, which enhance vascular reactivity and reduce vascular calcification in a mouse model of atherosclerosis, as well as improving cardiovascular function in old mice.
There are a variety of types of surgery:
- Angioplasty and stent placement: A catheter is first inserted into the blocked/narrowed part of your artery, followed by a second one with a deflated balloon which is passed through the catheter into the narrowed area. The balloon is then inflated, pushing the deposits back against the arterial walls, and then a mesh tube is usually left behind to prevent the artery from retightening.
- Coronary artery bypass surgery: This surgery creates a new pathway for blood to flow to the heart. Taking a healthy piece of vein, the surgeon attaches it to the coronary artery, just above and below the blockage to allow bypass.
- Endarterectomy: This is the general procedure for the surgical removal of plaque from the artery that has become narrowed, or blocked.
- Thrombolytic therapy: is a treatment used to break up masses of plaque inside the arteries via intravenous clot-dissolving medicine.
Cilostazol or pentoxifylline can improve symptoms in some. Cilostazol may improve walking distance for people who experience claudication due to peripheral artery disease, but there is no strong evidence to suggest that it improves the quality of life, decreases mortality, or decreases the risk of cardiovascular events.
Treatment with other drugs or vitamins are unsupported by clinical evidence, "but trials evaluating the effect of folate and vitamin B-12 on hyperhomocysteinemia, a putative vascular risk factor, are near completion".
After a trial of the best medical treatment outline above, if symptoms persist, patients may be referred to a vascular or endovascular surgeon. The benefit of revascularization is thought to correspond to the severity of ischemia and the presence of other risk factors for limb loss such as wound and infection severity.
- Angioplasty (PTA, or percutaneous transluminal angioplasty) can be done on solitary lesions in large arteries, such as the femoral artery, but angioplasty may not have sustained benefits. Patency rates following angioplasty are highest for iliac arteries, and decrease with arteries towards the toes. Other criteria that affect outcome following revascularization are length of lesion, and number of lesions. There does not appear to be long term advantages or sustained benefit to placing a stent following angioplasty in order to hold the narrowing of the superficial femoral artery open.
- Atherectomy, in which the plaque is scraped off of the inside of the vessel wall (albeit with no better results than angioplasty).
- Vascular bypass grafting can be performed to circumvent a diseased area of the arterial vasculature. The great saphenous vein is used as a conduit if available, although artificial (Gore-Tex or PTFE) material is often used for long grafts when adequate venous conduit is unavailable.
- When gangrene has set in, amputation is required to prevent infected tissues from causing sepsis a life-threatening illness.
- Thrombolysis and thrombectomy are used in cases of arterial thrombosis or embolism.
Arteriosclerosis is the thickening, hardening and loss of elasticity of the walls of arteries. This process gradually restricts the blood flow to one's organs and tissues and can lead to severe health risks brought on by atherosclerosis, which is a specific form of arteriosclerosis caused by the buildup of fatty plaques, cholesterol, and some other substances in and on the artery walls.
The aim of the medical treatment is to slow the progression of chronic kidney disease by reducing blood pressure and albumin levels. The current published guidelines define ideal BP of <130/80 mmHg for patients with hypertensive nephropathy; studies show that anything higher or lower than this can increase cardiovascular risk. According to the African American Study of Kidney Disease (AASK) trial, after an additional 5 years follow-up upon completion of the 10-year trial, up to 65% of the cohort had progressive nephropathy despite having controlled the mean systolic BP level <135 mmHg.
ACE inhibitors, angiotensin receptor blockers, direct renin inhibitors and aldosterone antagonists, are pharmacological treatments that can be used to lower BP to target levels; hence reducing neuropathy and proteinuria progression. The management plan should be individualized based on the condition of the patients including comorbidities and previous medical history.
In addition, there are lifestyle changes that can be made. Weight reduction, exercise, reducing salt intake can be done to manage hypertensive nephropathy.
The goal of treatment is to prevent the development or continuation of neurologic deficits. Treatments include observation, anticoagulation, stent implantation and carotid artery ligation.
Early treatment is essential to keep the affected limb viable. The treatment options include injection of an anticoagulant, thrombolysis, embolectomy, surgical revascularisation, or amputation. Anticoagulant therapy is initiated to prevent further enlargement of the thrombus. Continuous IV unfractionated heparin has been the traditional agent of choice.
If the condition of the ischemic limb is stabilized with anticoagulation, recently formed emboli may be treated with catheter-directed thrombolysis using intraarterial infusion of a thrombolytic agent (e.g., recombinant tissue plasminogen activator (tPA), streptokinase, or urokinase). A percutaneous catheter inserted into the femoral artery and threaded to the site of the clot is used to infuse the drug. Unlike anticoagulants, thrombolytic agents work directly to resolve the clot over a period of 24 to 48 hours.
Direct arteriotomy may be necessary to remove the clot. Surgical revascularization may be used in the setting of trauma (e.g., laceration of the artery). Amputation is reserved for cases where limb salvage is not possible. If the patient continues to have a risk of further embolization from some persistent source, such as chronic atrial fibrillation, treatment includes long-term oral anticoagulation to prevent further acute arterial ischemic episodes.
Decrease in body temperature reduces the aerobic metabolic rate of the affected cells, reducing the immediate effects of hypoxia. Reduction of body temperature also reduces the inflammation response and reperfusion injury. For frostbite injuries, limiting thawing and warming of tissues until warmer temperatures can be sustained may reduce reperfusion injury.
Treatment is aimed at controlling symptoms and improving the interrupted blood flow to the affected area of the body.
Medications include:
- Antithrombotic medication. These are commonly given because thromboembolism is the major cause of arterial embolism. Examples are:
- Anticoagulants (such as warfarin or heparin) and antiplatelet medication (such as aspirin, ticlopidine, and clopidogrel) can prevent new clots from forming
- Thrombolytics (such as streptokinase) can dissolve clots
- Painkillers given intravenously
- Vasodilators to relax and dilate blood vessels.
Appropriate drug treatments successfully produces thrombolysis and removal of the clot in 50% to 80% of all cases.
Antithrombotic agents may be administered directly onto the clot in the vessel using a flexible catheter ("intra-arterial thrombolysis"). Intra-arterial thrombolysis reduces thromboembolic occlusion by 95% in 50% of cases, and restores adequate blood flow in 50% to 80% of cases.
Surgical procedures include:
- Arterial bypass surgery to create another source of blood supply
- Embolectomy, to remove the embolus, with various techniques available:
- Thromboaspiration
- Angioplasty with balloon catheterization with or without implanting a stent Balloon catheterization or open embolectomy surgery reduces mortality by nearly 50% and the need for limb amputation by approximately 35%.
- Embolectomy by open surgery on the artery
If extensive necrosis and gangrene has set in an arm or leg, the limb may have to be amputated. Limb amputation is in itself usually remarkably well tolerated, but is associated with a substantial mortality (~50%), primarily because of the severity of the diseases in patients where it is indicated.
Mönckeberg's arteriosclerosis, or Mönckeberg's sclerosis, also called medial calcific sclerosis or Mönckeberg medial sclerosis, is a form of arteriosclerosis or vessel hardening, where calcium deposits are found in the muscular middle layer of the walls of arteries (the tunica media). It is an example of dystrophic calcification. This condition occurs as an age-related degenerative process. However, it can occur in pseudoxanthoma elasticum and idiopathic arterial calcification of infancy as a pathological condition, as well. Its clinical significance and cause are not well understood and its relationship to atherosclerosis and other forms of vascular calcification are the subject of disagreement.
Mönckeberg's arteriosclerosis is named after Johann Georg Mönckeberg, who first described it in 1903.
Prostacyclin (prostaglandin I) is commonly considered the most effective treatment for PAH. Epoprostenol (synthetic prostacyclin) is given via continuous infusion that requires a semi-permanent central venous catheter. This delivery system can cause sepsis and thrombosis. Prostacyclin is unstable, and therefore has to be kept on ice during administration. Since it has a half-life of 3 to 5 minutes, the infusion has to be continuous, and interruption can be fatal. Other prostanoids have therefore been developed. Treprostinil can be given intravenously or subcutaneously, but the subcutaneous form can be very painful. An increased risk of sepsis with intravenous Remodulin has been reported by the CDC. Iloprost is also used in Europe intravenously and has a longer half life. Iloprost was the only inhaled form of prostacyclin approved for use in the US and Europe, until the inhaled form of treprostinil was approved by the FDA in July 2009.
The dual (ET and ET) endothelin receptor antagonist bosentan was approved in 2001. Sitaxentan (Thelin) was approved for use in Canada, Australia, and the European Union, but not in the United States. In 2010, Pfizer withdrew Thelin worldwide because of fatal liver complications. A similar drug, ambrisentan is marketed as Letairis in the U.S. by Gilead Sciences.
Typically, Mönckeberg's arteriosclerosis is not associated with symptoms unless complicated by atherosclerosis, calciphylaxis, or accompanied by some other disease. However presence of Mönckeberg's arteriosclerosis is associated with poorer prognosis. This is probably due to vascular calcification causing increased arterial stiffness, increased pulse pressure and resulting in exaggerated damage to the heart and kidneys.
Arterial stiffness occurs as a consequence of biological aging and arteriosclerosis. Inflammation plays a major role in arteriosclerosis development, and consequently it is a major contributor in large arteries stiffening. Increased arterial stiffness is associated with an increased risk of cardiovascular events such as myocardial infarction and stroke, the two leading causes of death in the developed world. The World Health Organisation predicts that in 2010, cardiovascular disease will also be the leading killer in the developing world and represents a major global health problem.
Several degenerative changes that occur with age in the walls of large elastic arteries are thought to contribute to increased stiffening over time, including the mechanical fraying of lamellar elastin structures within the wall due to repeated cycles of mechanical stress; changes in the kind and increases in content of arterial collagen proteins, partially as a compensatory mechanism against the loss of arterial elastin and partially due to fibrosis; and crosslinking of adjacent collagen fibers by advanced glycation endproducts (AGEs).
How well a patient does depends on the location of the clot and to what extent the clot has blocked blood flow. Arterial embolism can be serious if not treated promptly.
Without treatment, it has a 25% to 30% mortality rate. The affected area can be permanently damaged, and up to approximately 25% of cases require amputation of an affected extremity.
Arterial emboli may recur even after successful treatment.
Exercise can improve symptoms, as can revascularization. Both together may be better than one intervention of its own.
Pharmacological options exist, as well. Medicines that control lipid profile, diabetes, and hypertension may increase blood flow to the affected muscles and allow for increased activity levels. Angiotensin converting enzyme inhibitors, beta-blockers, antiplatelet agents (aspirin and clopidogrel), naftidrofuryl, pentoxifylline, and cilostazol (selective PDE3 inhibitor) are used for the treatment of intermittent claudication. However, medications will not remove the blockages from the body. Instead, they simply improve blood flow to the affected area.
Catheter-based intervention is also an option. Atherectomy, stenting, and angioplasty to remove or push aside the arterial blockages are the most common procedures for catheter-based intervention. These procedures can be performed by interventional radiologists, interventional cardiologists, vascular surgeons, and thoracic surgeons, among others.
Surgery is the last resort; vascular surgeons can perform either endarterectomies on arterial blockages or perform an arterial bypass. However, open surgery poses a host of risks not present with catheter-based interventions.
According to the United States Renal Data System (USRDS), hypertensive nephropathy accounts for more than one-third of patients on hemodialysis and the annual mortality rate for patients on hemodialysis is 23.3%.
Haemodialysis is recommended for patients who progress to end-stage kidney disease (ESKD) and hypertensive nephropathy is the second most common cause of ESKD after diabetes.
Patient prognosis is dependent on numerous factors including age, ethnicity, blood pressure and glomerular filtration rate. Changes in lifestyle factors, such as reduced salt intake and increased physical activity have been shown to improve outcomes but are insufficient without pharmacological treatment.
Scleroderma renal crisis, the occurrence of acute renal failure and malignant hypertension (very high blood pressure with evidence of organ damage) in people with scleroderma, is effectively treated with drugs from the class of the ACE inhibitors. The benefit of ACE inhibitors extends even to those who have to commence dialysis to treat their kidney disease, and may give sufficient benefit to allow the discontinuation of renal replacement therapy.
Topical treatment for the skin changes of scleroderma do not alter the disease course, but may improve pain and ulceration. A range of NSAIDs (nonsteroidal anti-inflammatory drugs) can be used to ease painful symptoms, such as naproxen. There is limited benefit from steroids such as prednisone. Episodes of Raynaud's phenomenon sometimes respond to nifedipine or other calcium channel blockers; severe digital ulceration may respond to prostacyclin analogue iloprost, and the dual endothelin-receptor antagonist bosentan may be beneficial for Raynaud's phenomenon. The skin tightness may be treated systemically with methotrexate and ciclosporin. and the skin thickness treated with penicillamine.
When the heart contracts it generates a pulse or energy wave that travels through the circulatory system. The speed of travel of this pulse wave (pulse wave velocity (PWV)) is related to the stiffness of the arteries. Other terms that are used to describe the mechanical properties of arteries include elastance, or the reciprocal (inverse) of elastance, compliance. The relationship between arterial stiffness and pulse wave velocity was first predicted by Thomas Young in his Croonian Lecture of 1808 but is generally described by the Moens–Korteweg equation or the Bramwell–Hill equation. Typical values of PWV in the aorta range from approximately 5 m/s to >15 m/s.
Measurement of aortic PWV provides some of the strongest evidence concerning the prognostic significance of large artery stiffening. Increased aortic PWV has been shown to predict cardiovascular, and in some cases all cause, mortality in individuals with end stage renal failure, hypertension, diabetes mellitus and in the general population. However, at present, the role of measurement of PWV as a general clinical tool remains to be established. Devices are on the market that measure arterial stiffness parameters (augmentation index, pulse wave velocity). These include the Complior, CVProfilor, PeriScope, Hanbyul Meditech, Mobil-O-Graph NG, BP Plus (Pulsecor), PulsePen, BPLab Vasotens, Arteriograph, Vascular Explorer, and SphygmoCor.
Warfarin and vitamin K antagonists are anticoagulants that can be taken orally to reduce thromboembolic occurrence. Where a more effective response is required, heparin can be given (by injection) concomitantly. As a side effect of any anticoagulant, the risk of bleeding is increased, so the international normalized ratio of blood is monitored. Self-monitoring and self-management are safe options for competent patients, though their practice varies. In Germany, about 20% of patients were self-managed while only 1% of U.S. patients did home self-testing (according to one 2012 study). Other medications such as direct thrombin inhibitors and direct Xa inhibitors are increasingly being used instead of warfarin.
Disease progression may be slowed with immunosuppressives and other medications, and esophageal reflux, pulmonary hypertension and Raynaud phenomenon may benefit from symptomatic treatment. However, there is no cure for this disease as there is no cure for scleroderma in general.
Arterial thrombosis is platelet-rich, and inhibition of platelet aggregation with antiplatelet drugs such as aspirin may reduce the risk of recurrence or progression.
There is no cure for scleroderma, although relief of symptoms is often achieved. These include
- Raynaud's phenomenon with vasodilators such as calcium channel blockers, alpha blockers, serotonin receptor antagonists, angiotensin II receptor inhibitors, statins, local nitrates or iloprost
- Digital ulcers with phosphodiesterase 5 inhibitors (e.g., sildenafil) or iloprost
- Prevention of new digital ulcers with bosentan
- Malnutrition, secondary to intestinal flora overgrowth with tetracycline antibiotics like tetracycline
- Alveolitis with cyclophosphamide, azathioprine with or without corticosteroids
- Pulmonary arterial hypertension with endothelin receptor antagonists, phosphodiesterase 5 inhibitors and prostanoids
- Gastrooesophageal reflux disease with antacids or prokinetics
- Kidney crises with angiotensin converting enzyme inhibitors and angiotensin II receptor antagonists
Systemic disease-modifying treatment with immunosuppressants is often used. Immunosuppressants used in its treatment include azathioprine, methotrexate, cyclophosphamide, mycophenolate, intravenous immunoglobulin, rituximab, sirolimus, alefacept and the tyrosine kinase inhibitors, imatinib, nilotinib and dasatinib.
Experimental therapies under investigation include endothelin receptor antagonsits, tyrosine kinase inhibitors, beta-glycan peptides, halofuginone, basiliximab, alemtuzumab, abatacept and haematopoietic stem cell transplantation.
These ulcers are difficult to heal by basic wound care and require advanced therapy, such as hyperbaric oxygen therapy or bioengineered skin substitutes. If not taken care of in time, there are very high chances that these may become infected and eventually may have to be amputated. Individuals with history of previous ulcerations are 36 times more likely to develop another ulcer.
The Infarct Combat Project (ICP) is an international nonprofit organization founded in 1998 to fight ischemic heart diseases through education and research.