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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directing it into the cerebral circulation, and deploying a corkscrew-like device to ensnare the clot, which is then withdrawn from the body.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.
By definition, TIAs are transient, self-resolving, and do not cause permanent impairment. However, they are associated with an increased risk of subsequent ischemic strokes, which can be permanently disabling. Therefore, management centers around the prevention of future ischemic strokes and addressing any modifiable risk factors. The optimal regimen depends on the underlying cause of the TIA.
This new drug has been shown to home to ischemic stroke tissue as well as apoptotic neuronal cells of the penumbra region. This discovery may help in creating selective drug delivery for stroke patients.
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.
An antiplatelet, such as aspirin, is started for secondary prevention of stroke after most TIAs. An exception is TIAs due to blood clots originating from the heart, in which case anticoagulants are generally recommended. After TIA or minor stroke, aspirin therapy has been shown to reduce the short-term risk of recurrent stroke by 60-70%, and the long-term risk of stroke by 13%.
The typical therapy may include aspirin alone, a combination of aspirin plus extended-release dipyridamole, or clopidogrel alone. Clopidogrel and aspirin have similar efficacies and side effect profiles. Clopidogrel is more expensive and has a slightly decreased risk of GI bleed. There is some evidence that giving both aspirin and clopidogrel within 24 hours of a TIA or minor stroke is more effective than aspirin alone. Another antiplatelet, ticlopidine, is rarely used due to increased side effects.
70% of patients with carotid arterial dissection are between the ages of 35 and 50, with a mean age of 47 years.
The goal of treatment is to prevent the development or continuation of neurologic deficits. Treatments include observation, anticoagulation, stent implantation and carotid artery ligation.
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).
A cerebral infarction is an area of necrotic tissue in the brain resulting from a blockage or narrowing in the arteries supplying blood and oxygen to the brain. The restricted oxygen due to the restricted blood supply causes an ischemic stroke that can result in an infarction if the blood flow is not restored within a relatively short period of time. The blockage can be due to a thrombus, an embolus or an atheromatous stenosis of one or more arteries. Which arteries are problematic will determine which areas of the brain are affected (infarcted). These varying infarcts will produce different symptoms and outcomes. About one third will prove fatal.
The Infarct Combat Project (ICP) is an international nonprofit organization founded in 1998 to fight ischemic heart diseases through education and research.
Prognostics factors:
Lower Glasgow coma scale score, higher pulse rate, higher respiratory rate and lower arterial oxygen saturation level is prognostic features of in-hospital mortality rate in acute ischemic stroke.
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.
The major cause of acute limb ischaemia is arterial thrombosis (85%), while embolic occlusion is responsible for 15% of cases. In rare instances, arterial aneurysm of the popliteal artery has been found to create a thrombosis or embolism resulting in ischaemia.
Typically, tissue plasminogen activator may be administered within three to four-and-a-half hours of stroke onset if the patient is without contraindications (i.e. a bleeding diathesis such as recent major surgery or cancer with brain metastases). High dose aspirin can be given within 48 hours. For long term prevention of recurrence, medical regimens are typically aimed towards correcting the underlying risk factors for lacunar infarcts such as hypertension, diabetes mellitus and cigarette smoking. Anticoagulants such as heparin and warfarin have shown no benefit over aspirin with regards to five year survival.
Patients who suffer lacunar strokes have a greater chance of surviving beyond thirty days (96%) than those with other types of stroke (85%), and better survival beyond a year (87% versus 65-70%). Between 70% and 80% are functionally independent at 1 year, compared with fewer than 50% otherwise.
Occupational Therapy and Physical Therapy interventions are used in the rehabilitation of lacunar stroke. A physiotherapy program will improve joint range of motion of the paretic limb using passive range of motion exercises. When increases in activity are tolerated, and stability improvements are made, patients will progress from rolling to side-lying, to standing (with progressions to prone, quadruped, bridging, long-sitting and kneeling for example) and learn to transfer safely (from their bed to a chair or from a wheel chair to a car for example). Assistance and ambulation aids are used as required as the patient begins walking and lessened as function increases. Furthermore, splints and braces can be used to support limbs and joints to prevent complications such as contractures and spasticity. The rehabilitation healthcare team should also educate the patient and their family on common stroke symptoms and how to manage an onset of stroke. Continuing follow-up with a physician is essential so that the physician may monitor medication dosage and risk factors.
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
The primary intervention in acute limb ischaemia is emergency embolectomy using a Fogarty Catheter, providing the limb is still viable within the 4-6h timeframe. Other options include a vascular bypass to route blood flow around the clot.
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.
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.
Recent investigations have established that both moyamoya disease and arteriovenous fistulas (AVFs) of the lining of the brain, the dura, are associated with dural angiogenesis. These factors may represent a mechanism for ischemia contributing to the formation of dural AVFs. At least one case of simultaneous unilateral moyamoya syndrome and ipsilateral dural arteriovenous fistula has been reported at the Barrow Neurological Institute. In this case a 44-year-old man presented with headache, tinnitus, and an intraventricular hemorrhage, as seen on computed tomographic scans. Cerebral angiography showed a right moyamoya pattern and an ipsilateral dural AVF fed by branches of the external carotid artery and draining into the transverse sinus. This extremely rare coincidental presentation may have deeper pathogenic implications.
Risk factors for CRAO include the following: being between 60 and 65 years of age, being over the age of 40, male gender, hypertension, caucasian, smoking and diabetes mellitus. Additional risk factors include endocarditis, atrial myxoma, inflammatory diseases of the blood vessels, and predisposition to forming blood clots.
Prevention of atherosclerosis, which is a major risk factor of arterial embolism, can be performed e.g. by dieting, physical exercise and smoking cessation.
In case of high risk for developing thromboembolism, antithrombotic medication such as warfarin or coumadin may be taken prophylactically. Antiplatelet drugs may also be needed.
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.
Charcot–Bouchard aneurysms are aneurysms in the small penetrating blood vessels of the brain. They are associated with hypertension. The common artery involved is the lenticulostriate branch of the middle cerebral artery. Common locations of hypertensive hemorrhages include the putamen, caudate, thalamus, pons, and cerebellum.
As with any aneurysm, once formed they have a tendency to expand and eventually rupture, in keeping with the Law of Laplace.
It is estimated that lacunar infarcts account for 25% of all ischemic strokes, with an annual incidence of approximately 15 per 100,000 people. They may be more frequent in men and in people of African, Mexican, and Hong Kong Chinese descent.
Several treatments have been attempted for CRAS; however, none show definitive improvement in outcomes. The Undersea and Hyperbaric Medical Society lists Central Retinal Artery Occlusion (CRAO) as an approved indication for Hyperbaric Oxygen Therapy. This a treatment for CRAO that is covered by medical insurance in North America. Other treatments include ocular massage, anterior chamber paracentesis, and inhalation therapy of a mixture of 5% carbon dioxide and 95% oxygen.