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Surgery (open or endovascular) is the definite treatment of an aortic aneurysm. Medical therapy is typically reserved for smaller aneurysms or for elderly, frail patients where the risks of surgical repair exceed the risks of non-operative therapy (observation alone).
Medical therapy of aortic aneurysms involves strict blood pressure control. This does not treat the aortic aneurysm per se, but control of hypertension within tight blood pressure parameters may decrease the rate of expansion of the aneurysm.
The medical management of patients with aortic aneurysms, reserved for smaller aneurysms or frail patients, involves cessation of smoking, blood pressure control, use of statins and occasionally beta blockers. Ultrasound studies are obtained on a regular basis (i.e. every six or 12 months) to follow the size of the aneurysm.
Historically, the treatment of arterial aneurysms has been limited to either surgical intervention, or watchful waiting in combination with control of blood pressure. In recent years, endovascular or minimally invasive techniques have been developed for many types of aneurysms. Aneurysm Clips are used for surgical procedure i.e. clipping of aneurysms.
The size cut off for aortic aneurysm is crucial to its treatment. A thoracic aorta greater than 4.5 cm is generally defined as aneurysmal, while a size greater than 6 cm is the distinction for treatment, which can be either endovascular or surgical, with the former reserved for pathology at the descending aorta.
Indication for surgery may depend upon the size of the aneurysm. Aneurysms in the ascending aorta may require surgery at a smaller size than aneurysms in the descending aorta.
Treatment may be via open or via endovascular means.
The treatment options for asymptomatic AAA are management, surveillance with a view to eventual repair, and immediate repair. Two modes of repair are available for an AAA: open aneurysm repair, and endovascular aneurysm repair (EVAR). An intervention is often recommended if the aneurysm grows more than 1 cm per year or it is bigger than 5.5 cm. Repair is also indicated for symptomatic aneurysms.
Emergency treatment for individuals with a ruptured cerebral aneurysm generally includes restoring deteriorating respiration and reducing intracranial pressure. Currently there are two treatment options for securing intracranial aneurysms: surgical clipping or endovascular coiling. If possible, either surgical clipping or endovascular coiling is usually performed within the first 24 hours after bleeding to occlude the ruptured aneurysm and reduce the risk of rebleeding.
While a large meta-analysis found the outcomes and risks of surgical clipping and endovascular coiling to be statistically similar, no consensus has been reached. In particular, the large randomised control trial International Subarachnoid Aneurysm Trial appears to indicate a higher rate of recurrence when intracerebral aneurysms are treated using endovascular coiling. Analysis of data from this trial has indicated a 7% lower eight-year mortality rate with coiling, a high rate of aneurysm recurrence in aneurysms treated with coiling—from 28.6-33.6% within a year, a 6.9 times greater rate of late retreatment for coiled aneurysms, and a rate of rebleeding 8 times higher than surgically-clipped aneurysms.
Treatment for brain AVMs can be symptomatic, and patients should be followed by a neurologist for any seizures, headaches, or focal neurologic deficits. AVM-specific treatment may also involve endovascular embolization, neurosurgery or radiosurgery.
Embolization, that is, cutting off the blood supply to the AVM with coils, particles, acrylates, or polymers introduced by a radiographically guided catheter, may be used in addition to neurosurgery or radiosurgery, but is rarely successful in isolation except in smaller AVMs. Gamma knife may also be used.
There are currently two treatment options for brain aneurysms: surgical clipping or endovascular coiling. There is currently debate in the medical literature about which treatment is most appropriate given particular situations.
Surgical clipping was introduced by Walter Dandy of the Johns Hopkins Hospital in 1937. It consists of a craniotomy to expose the aneurysm and closing the base or neck of the aneurysm with a clip. The surgical technique has been modified and improved over the years.
Endovascular coiling was introduced by Guido Guglielmi at UCLA in 1991. It consists of passing a catheter into the femoral artery in the groin, through the aorta, into the brain arteries, and finally into the aneurysm itself. Platinum coils initiate a clotting reaction within the aneurysm that, if successful fill the aneurysm dome and prevent its rupture. Flow diverter can be used but not without complications sometimes.
No medical therapy has been found to be effective at decreasing the growth rate or rupture rate of asymptomatic AAAs. Blood pressure and lipids should, however, be treated per usual.
Head circumference measurements should be obtained regularly and monitored carefully to detect hydrocephalus. Neurosurgical procedures to relieve hydrocephalus are important. A ventriculoperitoneal shunt may be required in some infants. A pediatric cardiologist should be consulted to manage high-output failure, if present. Often patients need to be intubated. In most cases, the fistulous arteries feeding into the Vein of Galen must be blocked, thereby reducing the blood flow into the vein. Open surgery has a high morbidity and mortality. Recent advances over the past few decades have made endovascular embolization the preferred method of treatment. These treatments are preferred because they offer little threat to the surrounding brain tissue. However, there have been several reported cases of arteriovenous malformations recurring. The young age of many patients, the complex vascular anatomy, and the sensitive location of the Vein of Galen offer considerable challenges to surgeons. Another treatment option is Radiotherapy. Radiotherapy, also called radiosurgery, involves the use of focused beams to damage the blood vessel. Radiotherapy is often not pursued as a treatment because the effects of the procedure can take months or years and there is risk of damaging adjacent brain tissue.
Aneurysms can be treated by clipping the base of the aneurysm with a specially-designed clip. Whilst this is typically carried out by craniotomy, a new endoscopic endonasal approach is being trialled. Surgical clipping was introduced by Walter Dandy of the Johns Hopkins Hospital in 1937
After clipping, a catheter angiogram or CTA can be performed to confirm complete clipping.
Surgery is not always an option when the anatomy of the malformation creates too much of a risk. Recent improvements in endovascular procedures have made many cases, which were not surgically accessible, treatable. Endovascular treatments involve delivering drugs, balloons, or coils to the site of the malformation through blood vessels via catheters. These treatments work by limiting blood flow through the vein. There is, however, still risk of complications from endovascular treatments. The wall of the vein can be damaged during the procedure and, in some cases, the emboli can become dislodged and travel through the vascular system. Two-dimensional echocardiography with color-flow imaging and pulsed Doppler ultrasound was used to evaluate one fetus and five neonates with a Vein of Galen malformation. Color-flow imaging and pulsed Doppler ultrasonography provided anatomical and pathophysiological information regarding cardiac hemodynamics and intracranial blood flow; with the patient's clinical status, these methods provided a reliable, noninvasive means to evaluate the effectiveness of therapy and the need for further treatment in neonates with Vein of Galen malformations. When none of these procedures are viable, shunting can be used to ameliorate the pressure inside the varix. Seizures usually are managed with antiepileptic medications.
One approach used for treatment is embolization. A six-vessel angiogram is employed to determine the vascular supply to the fistula. Detachable coils, liquid embolic agents like NBCA, and onyx, or combinations of both are injected into the blood vessel to occlude the DAVF. Preoperative embolization can also be used to supplement surgery.
Some people live with this type of aneurysm for many years without any specific treatment. Treatment is limited to surgery (ventricular reduction) for this defect of the heart. However, surgery is not required in most cases but, limiting the patient's physical activity levels to lower the risk of making the aneurysm bigger is advised. Also ACE Inhibitors seem to prevent Left Ventricular remodeling and aneurysm formation.
Blood thinning agents may be given to help reduce the likelihood of blood thickening and clots forming, along with the use of drugs to correct the irregular rhythm of the heart (seen on the electrocardiogram)
DAVFs are also managed surgically. The operative approach varies depending on the location of the lesion.
Stereotactic radiosurgery
Stereotactic radiosurgery is used obliterating DAVFs post-embolization, and is considered an important adjunct. Use of this method, however, is limited to benign DAVFs that have failed other treatments.
Treatment depends on the location and size of the AVM and whether there is bleeding or not.
The treatment in the case of sudden bleeding is focused on restoration of vital function. Anticonvulsant medications such as phenytoin are often used to control seizure; medications or procedures may be employed to relieve intracranial pressure. Eventually, curative treatment may be required to prevent recurrent hemorrhage. However, any type of intervention may also carry a risk of creating a neurological deficit.
Preventive treatment of as yet unruptured brain AVMs has been controversial, as several studies suggested favorable long-term outcome for unruptured AVM patients not undergoing intervention. The NIH-funded longitudinal ARUBA study ("A Randomized trial of Unruptured Brain AVMs) compares the risk of stroke and death in patients with preventive AVM eradication versus those followed without intervention. Interim results suggest that fewer strokes occur as long as patients with unruptured AVM do not undergo intervention. Because of the higher than expected event rate in the interventional arm of the ARUBA study, NIH/NINDS stopped patient enrollment in April 2013, while continuing to follow all participants to determine whether the difference in stroke and death in the two arms changes over time.
Surgical elimination of the blood vessels involved is the preferred curative treatment for many types of AVM. Surgery is performed by a neurosurgeon who temporarily removes part of the skull (craniotomy), separates the AVM from surrounding brain tissue, and resects the abnormal vessels. While surgery can result in an immediate, complete removal of the AVM, risks exist depending on the size and the location of the malformation. The AVM must be resected en bloc, for partial resection will likely cause severe hemorrhage. The preferred treatment of Spetzler-Martin grade 1 and 2 AVMs in young, healthy patients is surgical resection due to the relatively small risk of neurological damage compared to the high lifetime risk of hemorrhage. Grade 3 AVMs may or may not be amenable to surgery. Grade 4 and 5 AVMs are not usually surgically treated.
Radiosurgery has been widely used on small AVMs with considerable success. The Gamma Knife is an apparatus used to precisely apply a controlled radiation dosage to the volume of the brain occupied by the AVM. While this treatment does not require an incision and craniotomy (with their own inherent risks), three or more years may pass before the complete effects are known, during which time patients are at risk of bleeding. Complete obliteration of the AVM may or may not occur after several years, and repeat treatment may be needed. Radiosurgery is itself not without risk. In one large study, nine percent of patients had transient neurological symptoms, including headache, after radiosurgery for AVM. However, most symptoms resolved, and the long-term rate of neurological symptoms was 3.8%.
Embolization is performed by interventional neuroradiologists and the occlusion of blood vessels most commonly is obtained with Ethylene-vinyl alcohol copolymer (Onyx) or N-butyl cyanoacrylate (NBCA). These substances are introduced by a radiographically guided catheter, and block vessels responsible for blood flow into the AVM. Embolization is frequently used as an adjunct to either surgery or radiation treatment. Embolization reduces the size of the AVM and during surgery it reduces the risk of bleeding. However, embolization alone may completely obliterate some AVMs. In high flow intranidal fistulas balloons can also be used to reduce the flow so that embolization can be done safely.
For newborns with transposition, prostaglandins can be given to keep the ductus arteriosus open which allows mixing of the otherwise isolated pulmonary and systemic circuits. Thus oxygenated blood that recirculates back to the lungs can mix with blood that circulates throughout the body. The arterial switch operation is the definitive treatment for dextro- transposition. Rarely the arterial switch is not feasible due to particular coronary artery anatomy and an atrial switch operation is preferred.
Simple l-TGA has a very good prognosis, with many individuals being asymptomatic and not requiring surgical correction.
In a number of cases, the (technically challenging) "double switch operation" has been successfully performed to restore the normal blood flow through the ventricles.
Treatment depends on whether the aneurysm is ruptured and may involve a combination of antimicrobial drugs, surgery and/or endovascular treatment.
Treatment is with neonatal surgical repair, with the objective of restoring a normal pattern of blood flow. The surgery is open heart, and the patient will be placed on cardiopulmonary bypass to allow the surgeon to work on a still heart. The heart is opened and the ventricular septal defect is closed with a patch. The pulmonary arteries are then detached from the common artery (truncus arteriosus) and connected to the right ventricle using a tube (a conduit or tunnel). The common artery, now separated from the pulmonary circulation, functions as the aorta with the truncal valve operating as the aortic valve. Most babies survive this surgical repair, but may require further surgery as they grow up. For example, the conduit does not grow with the child and may need to be replaced as the child grows. Furthermore, the truncal valve is often abnormal and may require future surgery to improve its function.
There have been cases where the condition has been diagnosed at birth and surgical intervention is an option. A number of these cases have survived well into adulthood.
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.
Palliative treatment is normally administered prior to corrective surgery in order to reduce the symptoms of d-TGA (and any other complications), giving the newborn or infant a better chance of surviving the surgery. Treatment may include any combination of:
Sometimes CHD improves without treatment. Other defects are so small that they do not require any treatment. Most of the time CHD is serious and requires surgery and/or medications. Medications include diuretics, which aid the body in eliminating water, salts, and digoxin for strengthening the contraction of the heart. This slows the heartbeat and removes some fluid from tissues. Some defects require surgical procedures to restore circulation back to normal and in some cases, multiple surgeries are needed.
Interventional cardiology now offers patients minimally invasive alternatives to surgery for some patients. The Melody Transcatheter Pulmonary Valve (TPV), approved in Europe in 2006 and in the U.S. in 2010 under a Humanitarian Device Exemption (HDE), is designed to treat congenital heart disease patients with a dysfunctional conduit in their right ventricular outflow tract (RVOT). The RVOT is the connection between the heart and lungs; once blood reaches the lungs, it is enriched with oxygen before being pumped to the rest of the body. Transcatheter pulmonary valve technology provides a less-invasive means to extend the life of a failed RVOT conduit and is designed to allow physicians to deliver a replacement pulmonary valve via a catheter through the patient’s blood vessels.
Most patients require lifelong specialized cardiac care, first with a pediatric cardiologist and later with an adult congenital cardiologist. There are more than 1.8 million adults living with congenital heart defects.
When PGE is administered to a newborn, it prevents the ductus arteriosus from closing, therefore providing an additional shunt through which to provide the systemic circulation with a higher level of oxygen.
Antibiotics may be administered preventatively. However, due to the physical strain caused by uncorrected d-TGA, as well as the potential for introduction of bacteria via arterial and central lines, infection is not uncommon in pre-operative patients.
Diuretics aid in flushing excess fluid from the body, thereby easing strain on the heart.
Analgesics normally are not used pre-operatively, but they may be used in certain cases. They are occasionally used partially for their sedative effects.
Cardiac glycosides are used to maintain proper heart rhythm while increasing the strength of each contraction.
Sedatives may be used palliatively to prevent a young child from thrashing about or pulling out any of their lines.