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Options include:
- Medications alone (an antiplatelet drug (or drugs) and control of risk factors for atherosclerosis).
- Medical management plus carotid endarterectomy or carotid stenting, which is preferred in patients at high surgical risk and in younger patients.
- Control of smoking, high blood pressure, and high levels of lipids in the blood.
The goal of treatment is to reduce the risk of stroke (cerebrovascular accident). Intervention (carotid endarterectomy or carotid stenting) can cause stroke; however, where the risk of stroke from medical management alone is high, intervention may be beneficial. In selected trial participants with asymptomatic severe carotid artery stenosis, carotid endarterectomy reduces the risk of stroke in the next 5 years by 50%, though this represents a reduction in absolute incidence of all strokes or perioperative death of approximately 6%. In most centres, carotid endarterectomy is associated with a 30-day stroke or mortality rate of < 3%; some areas have higher rates.
Clinical guidelines (such as those of National Institute for Clinical Excellence (NICE) ) recommend that all patients with carotid stenosis be given medication, usually blood pressure lowering medications, anti-clotting medications, anti-platelet medications (such as aspirin or clopidogrel), and especially statins (which were originally prescribed for their cholesterol-lowering effects but were also found to reduce inflammation and stabilize plaque).
NICE and other guidelines also recommend that patients with "symptomatic" carotid stenosis be given carotid endarterectomy urgently, since the greatest risk of stroke is within days. Carotid endarterectomy reduces the risk of stroke or death from carotid emboli by about half.
For people with stenosis but no symptoms, the interventional recommendations are less clear. Such patients have a historical risk of stroke of about 1-2% per year. Carotid endarterectomy has a surgical risk of stroke or death of about 2-4% in most institutions. In the large Asymptomatic Carotid Surgery Trial (ACST) endarterectomy reduced major stroke and death by about half, even after surgical death and stroke was taken into account. According to the Cochrane Collaboration the absolute benefit of surgery is small. For intervention using stents, there is insufficient evidence to support stenting rather than open surgery, and several trials, including the ACST-2, are comparing these 2 procedures.
The largest clinical trial performed, CREST, randomized patients at risk for a stroke from carotid artery blockage to either open surgery (carotid endarterectomy) or carotid stent placement with embolic protection. This trial followed patients for 4 years and found no overall difference in the primary end point of both treatment arms (myocardial infarctions, any perioperative strokes or ipsilateral strokes within 4 years, or death during procedure). Patients assigned to the surgical arm experienced more perioperative myocardial infarctions compared to the stenting group; however, the difference was not statistically significant (6.8% vs or 7.2% HR for stenting is 1.1 CI 0.81-1.51 P value 0.51) whereas patients assigned to the carotid stent arm experienced more periprocedural strokes compared to endarteretomy (6.4% vs 4.7% HR for stenting 1.5 P-0.03). There was no mortality difference and no difference for major (disabling) strokes between surgery and stenting. It was noted that there did seem to exist an age cutoff where below 75 years old endarterectomy provided more positive outcomes and over 75 stenting offered a better risk profile. However, it should be noted that the CREST trial was not designed for subgroup analysis and thus not powered enough to draw any statistically significant conclusions. A later study published in 2013 evaluated how these perioperative complications affect long-term survival. This study showed that experiencing a stroke within the first year conferred a two-fold lower survival rate (Hazard Ratio(HR) 6.6 [CI 3.7-12]) than those who experienced a perioperative myocardial infarction at two years post intervention (HR 3.6 [CI 2-6.8]). This difference in mortality, however, converges and becomes negligible at 5 years (HR 2.7 [CI 1.7-4.3] vs HR 2.8 [CI 1.8-4.3]). A 2010 study found benefits (reduced strokes) from carotid endarterectomy in those without symptoms who are under 75.
From analysis of the existing small treatment trials of cervical artery dissection (carotid and vertebral) it appears that aspirin and anticoagulation (heparin followed by warfarin) are equally effective in reducing the risk of further stroke or death. Anticoagulation is regarded as more powerful than antiplatelet therapy, but anticoagulants may increase the size of the hematoma and worsen obstruction of the affected artery. Anticoagulation may be relatively unsafe if a large stroke has already occurred, as hemorrhagic transformation is relatively common, and if the dissection extends into V4 (carrying a risk of subarachnoid hemorrhage). Anticoagulation may be appropriate if there is rapid blood flow (through a severely narrowed vessel) on transcranial doppler despite the use of aspirin, if there is a completely occluded vessel, if there are recurrent stroke-like episodes, or if free-floating blood clot is visible on scans. Warfarin is typically continued for 3–6 months, as during this time the flow through the artery usually improves, and most strokes happen within the first 6 months after the development of the dissection. Some regard 3 months as sufficient.
Professional guidelines in the UK recommend that patients with VA dissection should be enrolled in a clinical trial comparing aspirin and anticoagulation if possible. American guidelines state that the benefit of anticoagulation is not currently established.
Treatment is focused on reducing stroke episodes and damage from a distending artery. Four treatment modalities have been reported in the treatment of vertebral artery dissection. The two main treatments involve medication: anticoagulation (using heparin and warfarin) and antiplatelet drugs (usually aspirin). More rarely, thrombolysis (medication that dissolves blood clots) may be administered, and occasionally obstruction may be treated with angioplasty and stenting. No randomized controlled trials have been performed to compare the different treatment modalities. Surgery is only used in exceptional cases.
Many approaches have been promoted as methods to reduce or reverse atheroma progression:
- eating a diet of raw fruits, vegetables, nuts, beans, berries, and grains;
- consuming foods containing omega-3 fatty acids such as fish, fish-derived supplements, as well as flax seed oil, borage oil, and other non-animal-based oils;
- abdominal fat reduction;
- aerobic exercise;
- inhibitors of cholesterol synthesis (known as statins);
- low normal blood glucose levels (glycosylated hemoglobin, also called HbA1c);
- micronutrient (vitamins, potassium, and magnesium) consumption;
- maintaining normal, or healthy, blood pressure levels;
- aspirin supplement
- cyclodextrin can solubilize cholesterol, removing it from plaques
Put simply, take steps to live a healthy, sustainable lifestyle.
The goal of treatment is to prevent the development or continuation of neurologic deficits. Treatments include observation, anticoagulation, stent implantation and carotid artery ligation.
Medical treatments often focus on alleviating symptoms. However measures which focus on decreasing underlying atherosclerosis—as opposed to simply treating symptoms—are more effective. Non-pharmaceutical means are usually the first method of treatment, such as stopping smoking and practicing regular exercise. If these methods do not work, medicines are usually the next step in treating cardiovascular diseases, and, with improvements, have increasingly become the most effective method over the long term.
The key to the more effective approaches is to combine multiple different treatment strategies. In addition, for those approaches, such as lipoprotein transport behaviors, which have been shown to produce the most success, adopting more aggressive combination treatment strategies taken on a daily basis and indefinitely has generally produced better results, both before and especially after people are symptomatic.
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".
In last decade, similar to myocardial infarction treatment, thrombolytic drugs were introduced in the therapy of cerebral infarction. The use of intravenous rtPA therapy can be advocated in patients who arrive to stroke unit and can be fully evaluated within 3 h of the onset.
If cerebral infarction is caused by a thrombus occluding blood flow to an artery supplying the brain, definitive therapy is aimed at removing the blockage by breaking the clot down (thrombolysis), or by removing it mechanically (thrombectomy). The more rapidly blood flow is restored to the brain, the fewer brain cells die. In increasing numbers of primary stroke centers, pharmacologic thrombolysis with the drug tissue plasminogen activator (tPA), is used to dissolve the clot and unblock the artery.
Another intervention for acute cerebral ischaemia is removal of the offending thrombus directly. This is accomplished by inserting a catheter into the femoral artery, directing it into the cerebral circulation, and deploying a corkscrew-like device to ensnare the clot, which is then withdrawn from the body. Mechanical embolectomy devices have been demonstrated effective at restoring blood flow in patients who were unable to receive thrombolytic drugs or for whom the drugs were ineffective, though no differences have been found between newer and older versions of the devices. The devices have only been tested on patients treated with mechanical clot embolectomy within eight hours of the onset of symptoms.
Angioplasty and stenting have begun to be looked at as possible viable options in treatment of acute cerebral ischaemia. In a systematic review of six uncontrolled, single-center trials, involving a total of 300 patients, of intra-cranial stenting in symptomatic intracranial arterial stenosis, the rate of technical success (reduction to stenosis of <50%) ranged from 90-98%, and the rate of major peri-procedural complications ranged from 4-10%. The rates of restenosis and/or stroke following the treatment were also favorable. This data suggests that a large, randomized controlled trial is needed to more completely evaluate the possible therapeutic advantage of this treatment.
If studies show carotid stenosis, and the patient has residual function in the affected side, carotid endarterectomy (surgical removal of the stenosis) may decrease the risk of recurrence if performed rapidly after cerebral infarction. Carotid endarterectomy is also indicated to decrease the risk of cerebral infarction for symptomatic carotid stenosis (>70 to 80% reduction in diameter).
In tissue losses that are not immediately fatal, the best course of action is to make every effort to restore impairments through physical therapy, cognitive therapy, occupational therapy, speech therapy and exercise.
Anticoagulants may be started if the TIA is thought to be attributable to atrial fibrillation. Atrial fibrillation is an abnormal heart rhythm that may cause the formation of blood clots that can travel to the brain, resulting in TIAs or ischemic strokes. Atrial fibrillation increases stroke risk by five times, is thought to cause 10-12% of all ischemic strokes in the US. Anticoagulant therapy can decrease the relative risk of ischemic stroke in those with atrial fibrillation by 67% Warfarin is a common anticoagulant used, but direct acting oral anticoagulants (DOACs), such as apixaban, have been shown to be equally effective while also conferring a lower risk of bleeding. Generally, anticoagulants and antiplatelets are not used in combination, as they result in increased bleeding risk without a decrease in stroke risk. However, combined antiplatelet and anticoagulant therapy may be warranted if the patient has symptomatic coronary artery disease in addition to atrial fibrillation.
Sometimes, myocardial infarction (“heart attack”) may lead to the formation of a blood clot in one of the chambers of the heart. If this is thought to be the cause of the TIA, people may be temporarily treated with warfarin or other anticoagulant to decrease the risk of future stroke.
Blood pressure control may be indicated after TIA to reduce the risk of ischemic stroke. About 70% of patients with recent ischemic stroke are found to have hypertension, defined as systolic blood pressure (SBP) > 140 mmHg, or diastolic blood pressure (DBP) > 90 mmHg. Until recently, blood pressure goals have generally been SBP < 140 mmHg and DBP < 90 mmHg. However, recent studies suggest that a goal of SBP <130 mmHg may confer even greater benefit. Blood pressure control is often achieved using diuretics or a combination of diuretics and angiotensin converter enzyme inhibitors, although the optimal treatment regimen depends on the individual
If restenosis occurs without a stent, it is usually treated with more angioplasty. Once restenosis has occurred and been treated by angioplasty, the chances of restenosis occurring again are increased by a factor of 2. This treatment is also used if restenosis occurs at either the proximal or distal end of the stent.
If restenosis occurs within a stent (also known as in-stent stenosis), it may be treated with repeated angioplasty and insertion of another stent inside the original, sometimes with a drug-eluting stent.
Over the past 5 years, ISR is preferentially treated with a drug eluting balloon, which is a balloon coated with the same anticancer drugs that prevent restenosis. The Balloon avoids the need for a double layer of metal which is used when an in-stent restenosis is treated with another stent within the original stent
Alternative treatments include brachytherapy, or intracoronary radiation. The radiation kills cells and inhibits tissue growth (similar to a patient undergoing cancer therapy).
When atherosclerosis has become severe and caused irreversible ischemia, such as tissue loss in the case of peripheral artery disease, surgery may be indicated. Vascular bypass surgery can re-establish flow around the diseased segment of artery, and angioplasty with or without stenting can reopen narrowed arteries and improve bloodflow. Coronary artery bypass grafting without manipulation of the ascending aorta has demonstrated reduced rates of postoperative stroke and mortality compared to traditional on-pump coronary revascularization.
Patients with carotid or vertebral FMD should be medically managed to reduce the risk of a stroke. Aspirin 81 mg is typically prescribed for patients with carotid FMD. Antiplatelets and anticoagulants may be used to reduce the risk of blood clot formation. If a TIA or stroke are to occur, percutaneous angioplasty and antiplatelet therapy may be necessary.
Newer clinical trial results (2007), e.g. the COURAGE trial, have demonstrated that aggressively treating some of the physiologic behavioral factors that promote atheromas with "optimal medical therapy" (not opening narrowing(s), a.k.a. stenoses, per se) produced the most effective results in terms of improving human survival and quality of life for those identified as having already developed advanced cardiovascular disease with many vulnerable plaques.
There are several interventions that are often used to help prevent the recurrence of a watershed stroke; namely, nutritional interventions, as well as antiplatelet, anticoagulant, and statin drug use. Nutritional interventions, including increased consumption of certain amino acids, antioxidants, B-group vitamins, and zinc, have been shown to increase the recovery of neurocognitive function after a stroke. Antiplatelet drugs, such as aspirin, as well as anticoagulants, are used to help prevent blood clots and therefore embolisms, which can cause watershed strokes. Statin drugs are also used to control hyperlipidemia, another risk factor for watershed stroke.
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.
There is no known cure for FMD. However, treatment focuses on relieving symptoms associated with it. Medical management is the most common form of treatment. The best approach to medically managing these patients is constantly being reevaluated as more information is learned about the disease.
In this type of procedure, a narrowed blood vessel is expanded via angioplasty or stenting. A thin angiography catheter is inserted in a large groin blood vessel and advanced to the stenosis. Percutaneous treatment is less invasive than endarterectomy, usually requiring only local anesthesia. Endarterectomy is still considered safer though, as percutaneous treatments can lead to accidental dislodging of plaque or even arterial rupturing.
Treatment for cerebrovascular disease may include medication, lifestyle changes and/or surgery, depending on the cause.
Examples of medications are:
- antiplatelets (aspirin, clopidogrel)
- blood thinners (heparin, warfarin)
- antihypertensives (ACE inhibitors, beta blockers)
- anti-diabetic medications.
Surgical procedures include:
- endovascular surgery and vascular surgery (for future stroke prevention).
In the first stage of restenosis, administering anti-platelet drugs (called IIb/IIIa inhibitors) immediately after surgery greatly reduces the chance of a thrombosis occurring.
Drug-eluting stents are now being trialled in Europe, Canada and the USA, as well as in Asia-Pacific. These stents are coated with pharmaceuticals that inhibit tissue growth and thus reduce the risk of restenosis from scar-tissue and cell proliferation.
There has been some success with these new stents in reducing the occurrence of restenosis, with clinical studies showing an incidence rate of 5% or lower.
The natural history of this disorder is not well known. The long term outlook for patients with treated moyamoya seems to be good. While symptoms may seem to improve almost immediately after the in-direct EDAS, EMS, and multiple burr holes surgeries, it will take probably 6–12 months before new vessels can develop to give a sufficient blood supply. With the direct STA-MCA surgery, increased blood supply is immediate.
Once major stroke or bleeding take place, even with treatment, the patient may be left with permanent loss of function so it is very important to treat this condition promptly.
Dr. Michael Scott, MD discusses the success rate for Moyamoya surgery in
There is no cure for this disease. Drugs such as antiplatelet agents (including aspirin) are usually given to prevent clots, but surgery is usually recommended. Since moyamoya tends to affect only the internal carotid artery and nearby sections of the adjacent anterior and middle cerebral arteries, surgeons can direct other arteries, such as the external carotid artery or the superficial temporal artery to replace its circulation. The arteries are either sewn directly into the brain circulation, or placed on the surface of the brain to reestablish new circulation after a few weeks.
There are many operations that have been developed for the condition, but currently the most favored are the in-direct procedures EDAS, EMS, and multiple burr holes and the direct procedure STA-MCA. Direct superficial temporal artery (STA) to middle cerebral artery (MCA) bypass is considered the treatment of choice, although its efficacy, particularly for hemorrhagic disease, remains uncertain. Multiple burr holes have been used in frontal and parietal lobes with good neovascularisation achieved.
The EDAS (encephaloduroarteriosynangiosis) procedure is a synangiosis procedure that requires dissection of a scalp artery over a course of several centimeters and then making a small temporary opening in the skull directly beneath the artery. The artery is then sutured to a branch of the middle cerebral artery on the surface of the brain and the bone is replaced.
In the EMS (encephalomyosynangiosis) procedure, the temporalis muscle, which is in the temple region of the forehead, is dissected and through an opening in the skull placed onto the surface of the brain.
In the multiple burr holes procedure, multiple small holes (burr holes) are placed in the skull to allow for growth of new vessels into the brain from the scalp.
In the STA-MCA procedure, the scalp artery (superficial temporal artery or STA) is directly sutured to an artery on the surface of the brain (middle cerebral artery or MCA). This procedure is also commonly referred to as an EC-IC (External Carotid-Internal Carotid) bypass.
All of these operations have in common the concept of a blood and oxygen "starved" brain reaching out to grasp and develop new and more efficient means of bringing blood to the brain and bypassing the areas of blockage. The modified direct anastomosis and encephalo-myo-arterio-synangiosis play a role in this improvement by increasing cerebral blood flow (CBF) after the operation. A significant correlation is found between the postoperative effect and the stages of preoperative angiograms. It is crucial for surgery that the anesthesiologist have experience in managing children being treated for moyamoya, as the type of anesthesia they require is very different from the standard anesthetic children get for almost any other type of neurosurgical procedure.
Some of the most up to date treatments for Moyamoya are explained by top rated surgeons at Boston Children's Hospital in Massachusetts in these
Patients should discuss with their physician possible causes for their VBI symptoms. As discussed above, postural changes, exercise, and dehydration are some of the likely culprits. Treatment usually involves lifestyle modifications. For example, if VBI is attributed mainly to postural changes, patients are advised to slowly rise to standing position after sitting for a long period of time. An appropriate exercise regimen for each patient can also be designed in order to avoid the excessive pooling of blood in the legs. Dehydrated patients are often advised to increase their water intake, especially in hot, dry climates. Finally, when applicable, patients are often advised to stop smoking and to control their hypertension, diabetes, and cholesterol level.
In the event that a patient suffers a “drop attack,” and especially for the elderly population, the most important action is to be evaluated for associated head or other injuries. To prevent drop attacks, patients are advised to “go to the ground” before the knees buckle and shortly after feeling dizzy or experiencing changes in vision. Patients should not be concerned about the social consequences of suddenly sitting on the floor, whether in the mall or sidewalk, as such actions are important in preventing serious injuries.
Sometimes, to prevent further occlusion of blood vessels, patients are started on an antiplatelet agent (aspirin, clopidogrel, or aspirin/dipyridamole) or sometimes an anticoagulant (warfarin) once hemorrhage has been excluded with imaging.
For treatment of vertebrobasilar stenosis due to atherosclerosis, researchers from Stanford University found that intracranial angioplasty can be performed with an annual stroke rate in the territory of treatment of 3.2% and 4.4% for all strokes, including periprocedural events. Randomized control trials need to be performed.
Angioplasty with or without stenting is the best option for the treatment of renal artery stenosis due to fibromuscular dysplasia.