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The treatment for thrombosis depends on whether it is in a vein or an artery, the impact on the person, and the risk of complications from treatment.
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.
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.
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 for Thrombotic Storm may include lifelong anticoagulation therapy and/or thrombolytic therapy, plasmapherisis, and corticosteroids. Studies have shown that when anticoagulant therapy is withheld recurrence of thrombosis usually follows. INR is closely monitored in the course of treatment.
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.
Various studies have investigated the use of anticoagulation to suppress blood clot formation in cerebral venous sinus thrombosis. Before these trials had been conducted, there had been a concern that small areas of hemorrhage in the brain would bleed further as a result of treatment; the studies showed that this concern was unfounded. Clinical practice guidelines now recommend heparin or low molecular weight heparin in the initial treatment, followed by warfarin, provided there are no other bleeding risks that would make these treatments unsuitable. Some experts discourage the use of anticoagulation if there is extensive hemorrhage; in that case, they recommend repeating the imaging after 7–10 days. If the hemorrhage has decreased in size, anticoagulants are started, while no anticoagulants are given if there is no reduction.
The duration of warfarin treatment depends on the circumstances and underlying causes of the condition. If the thrombosis developed under temporary circumstances (e.g. pregnancy), three months are regarded as sufficient. If the condition was unprovoked but there are no clear causes or a "mild" form of thrombophilia, 6 to 12 months is advised. If there is a severe underlying thrombosis disorder, warfarin treatment may need to continue indefinitely.
Thrombolysis (removal of the blood clot with "clot buster" medication) has been described, either systemically by injection into a vein or directly into the clot during angiography. The 2006 European Federation of Neurological Societies guideline recommends that thrombolysis is only used in patients who deteriorate despite adequate treatment, and other causes of deterioration have been eliminated. It is unclear which drug and which mode of administration is the most effective. Bleeding into the brain and in other sites of the body is a major concern in the use of thrombolysis. American guidelines make no recommendation with regards to thrombolysis, stating that more research is needed.
Raised intracranial pressure, if severe or threatening vision, may require therapeutic lumbar puncture (removal of excessive cerebrospinal fluid), medication (acetazolamide), or neurosurgical treatment (optic nerve sheath fenestration or shunting). In certain situations, anticonvulsants may be used to try to prevent seizures. These situations include focal neurological problems (e.g. inability to move a limb) and focal changes of the brain tissue on CT or MRI scan. Evidence to support or refute the use of antiepileptic drugs as a preventive measure, however, is lacking.
Coronary thrombosis is the formation of a blood clot inside a blood vessel of the heart. This blood clot restricts blood flow within the heart. It is associated with narrowing of blood vessels subsequent to clotting. The condition is considered as a type of ischaemic heart disease, also known as a heart attack or myocardial infarction.
Thrombosis in the heart can lead to a myocardial infarction. Coronary thrombosis and myocardial infarction are sometimes used as synonyms, although this is technically inaccurate as the thrombosis refers to the blocking of blood vessels, while the infarction refers to the tissue death due to the consequent loss of blood flow to the heart tissue. The heart contains many connecting blood vessels, and depending upon the location of the thrombosis, the infarction may cause no symptoms. Coronary thrombosis is caused by atherosclerosis.This is when there is build up of cholesterol and fats in the artery walls. So the blood will clot because there isn't enough room for it to flow. The main causes of coronary thrombosis are stress, smoking, high blood pressure, and lack of exercise. Symptoms are sharp pains around the chest area, breathing difficulties, dizziness, and fainting. This is treated by taking Aspirin, Nitrates, or Beta Blockers.
Coronary thrombosis can be a complication associated with drug-eluting stents.
In 2004 the first adequately large scale study on the natural history and long-term prognosis of this condition was reported; this showed that at 16 months follow-up 57.1% of patients had full recovery, 29.5%/2.9%/2.2% had respectively minor/moderate/severe symptoms or impairments, and 8.3% had died. Severe impairment or death were more likely in those aged over 37 years, male, affected by coma, mental status disorder, intracerebral hemorrhage, thrombosis of the deep cerebral venous system, central nervous system infection and cancer. A subsequent systematic review of nineteen studies in 2006 showed that mortality is about 5.6% during hospitalisation and 9.4% in total, while of the survivors 88% make a total or near-total recovery. After several months, two thirds of the cases has resolution ("recanalisation") of the clot. The rate of recurrence was low (2.8%).
In children with CVST the risk of death is high. Poor outcome is more likely if a child with CVST develops seizures or has evidence of venous infarction on imaging.
The best course of treatment varies from case to case. The physician must take into account the details in the case before deciding on the appropriate treatment. No treatment is effective for every patient.
Treatment depends on many factors, including:
- Location of lesions
- Anatomy of lesions
- Patient risk factors
- Procedural risk
- Clinical presentation of symptoms
- Duration of symptoms
- etc.
Blood clots are a relatively common occurrence in the general population and are seen in approximately 1-2% of the population by age 60. Typically blood clots develop in the deep veins of the lower extremities, deep vein thrombosis (DVT) or as a blood clot in the lung, pulmonary embolism (PE). A very small number of people who develop blood clots have a more serious and often life-threatening condition, known as Thrombotic Storm (TS). TS is characterized by the development of more than one blood clot in a short period of time. These clots often occur in multiple and sometimes unusual locations in the body and are often difficult to treat. TS may be associated with an existing condition or situation that predisposes a person to blood clots such as injury, infection, or pregnancy. In many cases a risk assessment will identify interventions that will prevent the formation of blood clots.
While the mechanism or pathogenesis is not completely understood mostly due to its rarity, the medical community has developed a new interest in learning more about this syndrome. Dr. Craig S. Kitchens first described TS in six case studies. In these cases he described a collection of similar features observed in six patients, suggesting this may be accounted for by a new syndrome.
An embolism is the lodging of an embolus, a blockage-causing piece of material, inside a blood vessel. The embolus may be a blood clot (thrombus), a fat globule (fat embolism), a bubble of air or other gas (gas embolism), or foreign material. An embolism can cause partial or total blockage of blood flow in the affected vessel. Such a blockage (a vascular occlusion) may affect a part of the body distant from where the embolus originated. An embolism in which the embolus is a piece of thrombus is called a thromboembolism. Thrombosis, the process of thrombus formation, often leads to thromboembolism.
An embolism is usually a pathological event, i.e., accompanying illness or injury. Sometimes it is created intentionally for a therapeutic reason, such as to stop bleeding or to kill a cancerous tumor by stopping its blood supply. Such therapy is called embolization.
Treatment with compression stockings should be offered to patients with lower extremity superficial phlebitis, if not contraindicated (e.g., peripheral artery disease). Patients may find them helpful for reducing swelling and pain once the acute inflammation subsides.
Nonsteroidal anti-inflammatory drugs (NSAID) are effective in relieving the pain associated with venous inflammation and were found in a randomized trial to significantly decrease extension and/or recurrence of superficial vein thrombosis.
Anticoagulation for patients with lower extremity superficial thrombophlebitis at increased risk for thromboembolism (affected venous segment of ≥5 cm, in proximity to deep venous system, positive medical risk factors).
Treatment with fondaparinux reduces the risk of subsequent venous thromboembolism.
Surgery reserved for extension of the clot to within 1 cm of the saphenofemoral junction in patients deemed unreliable for anticoagulation, failure of anticoagulation and patients with intense pain. Surgical therapy with ligation of saphenofemoral junction or stripping of thrombosed superficial veins appears to be associated higher rates of venous thromboembolism compared with treatment with anitcoagulants.
There are different types of embolism, some of which are listed below.
Management of the underlying defect is proportional to the severity of the clinical presentation. Leg swelling and pain is best evaluated by vascular specialists (vascular surgeons, interventional cardiologists, interventional radiologists) who both diagnose and treat arterial and venous diseases to ensure that the cause of the extremity pain is evaluated. The diagnosis needs to be confirmed with some sort of imaging that may include magnetic resonance venography, venogram and usually confirmed with intravascular ultrasound because the flattened vein may not be noticed on conventional venography. In order to prevent prolonged swelling or pain from the consequences of the backed up blood from the compressed iliac vein, flow needs to be improved out of the leg. Uncomplicated cases may be managed with compression stockings.
Severe May-Thurner syndrome may require thrombolysis if there is a recent onset of thrombosis, followed by angioplasty and stenting of the iliac vein after confirming the diagnosis with a venogram or an intravascular ultrasound. A stent may be used to support the area from further compression following angioplasty. As the name implies, there classically is not a thrombotic component in these cases, but thrombosis may occur at any time.
If the patient has extensive thrombosis, it may be appropriate to consider pharmacologic and/or mechanical (also known as pharmacomechanical) thrombectomy. This is currently being studied to determine whether this will decrease the incidence of post-thrombotic syndrome.
Some 125,000 cases a year have been reported in the United States, but actual incidence of spontaneous thrombophlebitis is unknown.
A fourfold increased incidence from the third to the eight decade in men and a preponderance among women of approximately 55-70%.
The average mean age of affected patients is 60 years.
Thrombophlebitis can develop along the arm, back, or neck veins, the leg is by far the most common site. When it occurs in the leg, the great saphenous vein is usually involved, although other locations are possible.
Passage of a clot (thrombus) from a systemic vein to a systemic artery. When clots in systemic veins break off (embolize), they travel first to the right side of the heart and, normally, then to the lungs where they lodge, causing pulmonary embolism. On the other hand, when there is a hole at the septum, either upper chambers of the heart (an atrial septal defect) or lower chambers of the heart (ventricular septal defects), a clot can cross from the right to the left side of the heart, then pass into the systemic arteries as a paradoxical embolism. Once in the arterial circulation, a clot can travel to the brain, block a vessel there, and cause a stroke (cerebrovascular accident).
Standard medical treatment consists of anticoagulants (blood thinners), diuretics, and oxygen. Lifelong anticoagulation is recommended, even after PEA. Routine inferior vena cava filter placement is not recommended.
In patients with non-operable CTEPH or persistent/recurrent PH after PEA, there is evidence for benefit from pulmonary vasodilator drug treatment. The microvascular disease component in CTEPH has provided the rationale for off-label use of drugs approved for PAH. Currently, only riociguat (a stimulator of soluble guanylate cyclase) is approved for treatment of adults with inoperable CTEPH or persistent or recurrent CTEPH after surgical treatment. Other drug trials are ongoing in patients with inoperable CTEPH, with macitentan recently proving efficacy and safety in MERIT
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.
Decision making for patients with CTEPH can be complex and needs to be managed by CTEPH teams in expert centres. CTEPH teams comprise cardiologists and pulmonologists with specialist PH training, radiologists, experienced PEA surgeons with a significant caseload of CTEPH patients per year and physicians with percutaneous interventional expertise. Currently, there are three recognised targeted treatment options available: pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA) and pulmonary vasodilator drug treatment for inoperable patients.
Specialist imaging using either magnetic resonance or invasive PA is necessary to determine risks and benefits of interventional treatment with PEA or BPA.
The Infarct Combat Project (ICP) is an international nonprofit organization founded in 1998 to fight ischemic heart diseases through education and research.
In medicine, May-Thurner syndrome (MTS), also known as the iliac vein compression syndrome, is a rare condition in which compression of the common venous outflow tract of the left lower extremity may cause discomfort, swelling, pain or blood clots, called deep venous thrombosis (DVT), in the iliofemoral vein.
The specific problem is compression of the left common iliac vein by the overlying right common iliac artery. This leads to pooling or stasis of blood, predisposing the individual to the formation of blood clots. Uncommon variations of MTS have been described, such as the right common iliac vein getting compressed by the right common iliac artery.
In the 21st century the May-Thurner syndrome definition has been expanded to a broader disease profile known as nonthrombotic iliac vein lesions (NIVL) which can involve both the right and left iliac veins as well as multiple other named venous segments. This syndrome frequently manifests as pain when the limb is dependent (hanging down the edge of a bed/chair) and/or significant swelling of the whole limb.
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.
A paradoxical embolism, also called a crossed embolism, refers to an embolus which is carried from the venous side of circulation to the arterial side, or vice versa. It is a kind of stroke or other form of arterial thrombosis caused by embolism of a thrombus (blood clot), air, tumor, fat, or amniotic fluid of venous origin, which travels to the arterial side through a lateral opening in the heart, such as a patent foramen ovale, or arteriovenous shunts in the lungs.
The opening is typically an atrial septal defect, but can also be a ventricular septal defect.
Paradoxical embolisms represent two percent of arterial emboli.
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.