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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.
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.
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.
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.
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.
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.
Treatment depends on whether the aneurysm is ruptured and may involve a combination of antimicrobial drugs, surgery and/or endovascular treatment.
Traumatic aortic rupture is treated with surgery. However, morbidity and mortality rates for surgical repair of the aorta for this condition are among the highest of any cardiovascular surgery. For example, surgery is associated with a high rate of paraplegia, because the spinal cord is very sensitive to ischemia (lack of blood supply), and the nerve tissue can be damaged or killed by the interruption of the blood supply during surgery.
A less invasive option for treatment is endovascular repair, which does not require open thoracotomy and can be safer for people with other injuries to organs.
Since high blood pressure could exacerbate an incomplete tear in the aorta or even separate it completely from the heart, which would almost inevitably kill the patient, hospital staff take measures to keep the blood pressure low. Such measures include giving pain medication, keeping the patient calm, and avoiding procedures that could cause gagging or vomiting. Beta blockers and vasodilators can be given to lower the blood pressure, and intravenous fluids that might normally be given are foregone to avoid raising it.
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.
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.
Aortic ruptures can be repaired surgically via open aortic surgery or using endovascular therapy (EVAR), regardless of cause, just as non-ruptured aortic aneurysms are repaired. An aortic occlusion balloon can be placed to stabilize the patient and prevent further blood loss prior to the induction of anesthesia.
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 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.
Type 1 and Type 2 FAD call for the same treatment: immediate surgery to replace the aorta. Surgery is required due to the high risk of mortality. Type 3 is less severe and requires the maintenance of blood pressure through diet and exercise. Upon diagnosing someone with FAD intravenous antihypertensive treatment is frequently used. Often intravenous sodium nitroprusside is used for its efficiency in lessening the pulsatile load thus reducing blood pressure. Reducing this force slows the progression of the dissection. Surgical success depends on age, severity of symptoms, postoperative organ dysfunction and stroke. Surgical intervention is always indicated in Type 1 cases. Aortic surgery is palliative, not curative. The goal is to merely to prevent rupture, restore blood flow, and fix any aortic valve dysfunction. Post operative protocols include frequent monitoring of the aorta diameter. Statins and beta blockers are also popular treatments used to reduce future plaque build up and blockage of epinephrine receptors as a way to control heart rate and blood pressure.
Long term treatment should also include regular check ups every 3 to 6 months. A CT scan or MRI is recommended, along with required chest x-rays. Antihypertensive therapy with beta adrenergic antagonists is required regardless of medical versus surgical treatment. Ten to twenty percent of those who choose surgical intervention are re-operated on due to compression, aneurysm development or blood leakage.
Aortic dissection generally presents as a hypertensive emergency, and the prime consideration of medical management is strict blood pressure control. The target blood pressure should be a mean arterial pressure (MAP) of 60 to 75 mmHg, or the lowest blood pressure tolerated. Initial decreases should be by about 20%.
Another factor is to reduce the shear-force dP/dt (force of ejection of blood from the left ventricle). Long-term management of physical, emotional, and psychological stresses are important to controlling blood pressure.
Beta blockers are the first-line treatment for patients with acute and chronic aortic dissection. In acute dissection, fast-acting agents which can be given intravenously and have doses that are easier to adjust (such as esmolol, propranolol, or labetalol) are preferred. Vasodilators such as sodium nitroprusside can be considered for people with ongoing high blood pressure, but they should never be used alone, as they often stimulate a reflexive increase in the heart rate.
Calcium channel blockers can be used in the treatment of aortic dissection, particularly if a contraindication to the use of beta blockers exists. The calcium channel blockers typically used are verapamil and diltiazem, because of their combined vasodilator and negative inotropic effects.
If the individual has refractory hypertension (persistent hypertension on the maximum doses of three different classes of antihypertensive agents), an involvement of the renal arteries in the aortic dissection plane should be considered.
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.
Medical therapy of aneurysm of the aortic sinus includes blood pressure control through the use of drugs, such as beta blockers.
Another approach is surgical repair. The determination to perform surgery is usually based upon the diameter of the aortic root (with 5 centimeters being a rule of thumb - a normal size is 2-3 centimeters) and the rate of increase in its size (as determined through repeated echocardiography).
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)
Management involves general measures to stabilize the person while also using specific investigations and treatments. These include the prevention of rebleeding by obliterating the bleeding source, prevention of a phenomenon known as vasospasm, and prevention and treatment of complications.
Stabilizing the person is the first priority. Those with a depressed level of consciousness may need to be intubated and mechanically ventilated. Blood pressure, pulse, respiratory rate, and Glasgow Coma Scale are monitored frequently. Once the diagnosis is confirmed, admission to an intensive care unit may be preferable, especially since 15 percent may have further bleeding soon after admission. Nutrition is an early priority, with by mouth or nasogastric tube feeding being preferable over parenteral routes. In general, pain control is restricted to less-sedating agents such as codeine, as sedation may impact on the mental status and thus interfere with the ability to monitor the level of consciousness. Deep vein thrombosis is prevented with compression stockings, intermittent pneumatic compression of the calves, or both. A bladder catheter is usually inserted to monitor fluid balance. Benzodiazepines may be administered to help relieve distress. Antiemetic drugs should be given to awake persons.
People with poor clinical grade on admission, acute neurologic deterioration, or progressive enlargement of ventricles on CT scan are, in general, indications for the placement of an external ventricular drain by a neurosurgeon. The external ventricular drain may be inserted at the bedside or in the operating room. In either case, strict aseptic technique must be maintained during insertion. In people with aneurysmal subarachnoid hemorrhage the EVD is used to remove cerebrospinal fluid, blood, and blood byproducts that increase intracranial pressure and may increase the risk for cerebral vasospasm.
Indications for the surgical treatment of aortic dissection include an acute proximal aortic dissection and an acute distal aortic dissection with one or more complications. Complications include compromise of a vital organ, rupture or impending rupture of the aorta, retrograde dissection into the ascending aorta, and a history of Marfan syndrome or Ehlers-Danlos syndrome.
The objective in the surgical management of aortic dissection is to resect (remove) the most severely damaged segments of the aorta and to obliterate the entry of blood into the false lumen (both at the initial intimal tear and any secondary tears along the vessel). While excision of the intimal tear may be performed, it does not significantly change mortality.
The particular treatment used depends on the segment or segments of aorta involved. Some treatments are:
- Open aortic surgery with replacement of the damaged section of aorta with a tube graft (often made of Dacron) when no damage to the aortic valve is seen
- Bentall procedure — replacement of the damaged section of aorta and replacement of the aortic valve
- David procedure — replacement of the damaged section of aorta and reimplantation of the aortic valve
- Thoracic endovascular aortic repair, a minimally invasive surgical procedure usually combined with on-going medical management
- Replacement of the damaged section of aorta with a sutureless vascular ring connector-reinforced Dacron graft: The vascular ring connector is a titanic ring used as a stent in the vascular graft to achieve a quick, blood-sealed, and sutureless anastomosis. Two furrows on the surface of the ring are for fixation of the vascular graft and the aorta. The tapes used to tie against the ring provide a larger contact surface area than the traditional stitches, thus it provides stronger anastomosis and better surgical results.
A number of comorbid conditions increase the surgical risk of repair of an aortic dissection. These conditions include the following:
- Prolonged preoperative evaluation (increased length of time prior to surgery)
- Advanced age
- Comorbid disease states (e.g.: coronary artery disease)
- Aneurysm leakage
- Cardiac tamponade
- Shock
- Past history of myocardial infarction
- History of kidney failure (either acute or chronic kidney failure)
The treatment for myocardial rupture is supportive in the immediate setting and surgical correction of the rupture, if feasible. A certain small percentage of individuals do not seek medical attention in the acute setting and survive to see the physician days or weeks later. In this setting, it may be reasonable to treat the rupture medically and delay or avoid surgery completely, depending on the individual's comorbid medical issues.
Currently, there is controversy over whether or not inheritance truly plays a role in FAD, and if so which gene it acts upon. FAD does not come from strictly one predisposing factor, such as hypertension. It is suggested that the combination of environmental factors along with genetics may contribute to causing FAD. Before newer and more effective cures and therapies can be developed, first the specific gene mutation must be identified. Until such a gene is determined, scientists say patient education, and physician awareness is vital. Currently scientists have found animal models to be beneficial in understanding the pathology behind FAD. In the future there is hope to develop drugs that will better support and strengthen the aortic wall. Endovascular methods of treatment are becoming increasingly popular, and scientists hope to use this technique in both acute and chronic cases.