Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
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.
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.
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).
The effect of statins on the progression of AS is unclear. The latest trials do not show any benefit in slowing AS progression, but did demonstrate a decrease in ischemic cardiovascular events.
In general, medical therapy has relatively poor efficacy in treating aortic stenosis. However, it may be useful to manage commonly coexisting conditions that correlate with aortic stenosis:
- Any angina is generally treated with beta-blockers and/or calcium blockers. Nitrates are contraindicated due to their potential to cause profound hypotension in aortic stenosis.
- Any hypertension is treated aggressively, but caution must be taken in administering beta-blockers.
- Any heart failure is generally treated with digoxin and diuretics, and, if not contraindicated, cautious administration of ACE inhibitors.
While observational studies demonstrated an association between lowered cholesterol with statins and decreased progression, a randomized clinical trial published in 2005 failed to find any effect on calcific aortic stenosis. A 2007 study did demonstrate a slowing of aortic stenosis with the statin rosuvastatin.
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.
The goal of treatment is to prevent the development or continuation of neurologic deficits. Treatments include observation, anticoagulation, stent implantation and carotid artery ligation.
Aortic valve repair or aortic valve reconstruction describes the reconstruction of both form and function of the native and dysfunctioning aortic valve. Most frequently it is applied for the treatment of aortic regurgitation. It can also become necessary for the treatment of an aortic aneurysm, less frequently for congenital aortic stenosis.
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 definitive treatment for Heyde's syndrome is surgical replacement of the aortic valve. Recently, it has been proposed that transcatheter aortic valve implantation (TAVI) can also be used for definitive management. Direct surgical treatment of the bleeding (e.g. surgical resection of the bleeding portion of the bowel) is only rarely effective.
Medical management of symptoms is possible also, although by necessity temporary, as definitive surgical management is required to bring levels of von Willebrand factor back to normal. In severe bleeding, blood transfusions and IV fluid infusions can be used to maintain blood pressure. In addition, desmopressin (DDAVP) is known to be effective in people with von Willebrand's disease, including people with valvular heart disease. Desmopressin stimulates release of von Willebrand factor from blood vessel endothelial cells by acting on the V2 receptor, which leads to decreased breakdown of Factor VIII. Desmopressin is thus sometimes used directly to treat mild to moderate acquired von Willebrand's disease and is an effective prophylactic agent for the reduction of bleeding during heart valve replacement surgery.
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.
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.
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.
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
Angioplasty with or without stenting is the best option for the treatment of renal artery stenosis due to fibromuscular dysplasia.
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 Norwood procedure is a procedure to correct fetal aortic stenosis that occurs after birth. This typically consists of three surgeries creating and removing shunts. The atrial septum is removed, the aortic arch is reconstructed to remove any hypoplasia, and then the main pulmonary artery is connected into this reconstructed arch, resulting in the right ventricle ejecting directly into systemic circulation. In the end, the right ventricle is pumping blood to systemic circulation and to the lungs. However, this procedure carries a very high risk of failure and the patient will likely require a heart transplant.
Another treatment option is to correct the stenosis in utero. In this procedure, fetal positioning is crucial. It is important that the left chest is located anteriorly, and that there are no limbs between the uterine wall and the apex of the left ventricle. The LV apex needs to be within 9 cm of the abdominal wall and the left ventricle outflow track has to be parallel to the intended cannula course in order for the wire to be blindly directed at the aortic valve. A 11.5 cm long, 19-gauge cannula and stylet needle passes through the mother’s abdomen, uterine wall, and fetal chest wall into the left ventricle of the fetus. Then a 0.014 inch guide wire is passed across the stenosis aortic valve, where a balloon is inflated to stretch the aortic annulus.
An alternative to the Norwood procedure is known as the hybrid procedure, was developed in 2008. In the hybrid procedure, bilateral pulmonary artery bands are positioned to limit pulmonary flow while, at the same time, placing a stent in the ductus arteriosus to hold it open. This maintains the connection between the aorta and the systemic circulation. A balloon atrial septostomy is also done. This ensures that there is enough of a connection between the two atria of the heart to provide open blood flow and mixing of oxygen rich and poor blood This procedure spares the baby from undergoing open heart surgery until they are older. They typically come back at 4–6 months of age when they are stronger for the open heart surgery.
It is initially treated with medications, including diuretics, and medications for blood pressure control. When high-grade renal artery stenosis is documented and blood pressure cannot be controlled with medication, or if renal function deteriorates, surgery may be resorted to. The most commonly used procedure is a minimally-invasive angioplasty with or without stenting. It is unclear if this approach yields better results than the use of medications alone. It is a relatively safe procedure. If all else fails and the kidney is thought to be worsening hypertension and revascularization with angioplasty or surgery does not work, then surgical removal of the affected kidney (nephrectomy) may significantly improve high blood pressure.
The mainstay of treatment for CCF is endovascular therapy. This may be transarterial (mostly in the case of direct CCF) or transvenous (most commonly in indirect CCF). Occasionally, more direct approaches, such as direct transorbital puncture of the cavernous sinus or cannulation of the draining superior orbital vein are used when conventional approaches are not possible. Spontaneous resolution of indirect fistulae has been reported but is uncommon. Staged manual compression of the ipsilateral carotid has been reported to assist with spontaneous closure in selected cases.
Direct CCF may be treated by occlusion of the affected cavernous sinus (coils, balloon, liquid agents), or by reconstruction of the damaged internal carotid artery (stent, coils or liquid agents).
Indirect CCF may be treated by occlusion of the affected cavernous sinus with coils, liquid agents or a combination of both.
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 terms of treatment for pulmonary valve stenosis, valve replacement or surgical repair (depending upon whether the stenosis is in the valve or vessel) may be indicated. If the valve stenosis is of congenital origin, balloon valvuloplasty is another option, depending on the case.
Valves made from animal or human tissue (are used for valve replacement), in adults metal valves can be used.
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.
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.
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.
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.