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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.
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.
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.
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.
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).
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.
Surgical treatment involves resection of the stenosed segment and re-anastomsis. Two complications specific to this surgery are Left recurrent nerve palsy and chylothorax, as the recurrent laryngeal nerve and thoracic duct are in the vicinity. Chylothorax is a troublesome complication and is usually managed conservatively by adjusting the diet to eliminate long chain fatty acids and supplementing medium chain triglycerides. When conservative management fails surgical intervention is required. Fluorescein dye can aid in the localisation of chyle leak.
Treatment is generally not necessary in people without symptoms. In moderate cases, echocardiography is performed every 1–2 years to monitor the progression, possibly complemented with a cardiac stress test. In severe cases, echocardiography is performed every 3–6 months. In both moderate and mild cases, the person should immediately make a revisit or be admitted for inpatient care if any new related symptoms appear. There are no therapeutic options currently available to treat people with aortic valve stenosis; however, studies have indicated that the disease occurs as a result of active cellular processes, suggesting that targeting these processes may lead to viable therapeutic approaches.
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)
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.
Medical therapy of chronic aortic insufficiency that is stable and asymptomatic involves the use of vasodilators. Trials have shown a short term benefit in the use of ACE inhibitors or angiotensin II receptor antagonists, nifedipine, and hydralazine in improving left ventricular wall stress, ejection fraction, and mass. The goal in using these pharmacologic agents is to decrease the afterload so that the left ventricle is somewhat spared. The regurgitant fraction may not change significantly, since the gradient between the aortic and left ventricular pressures is usually fairly low at the initiation of treatment. Other rather conservative medical treatments for stable and asymptomatic cases include low sodium diet, diuretics, digoxin, calcium blockers and avoiding very strenuous activity.
As of 2007, the American Heart Association no longer recommends antibiotics for endocarditis prophylaxis before certain procedures in patients with aortic insufficiency. Antibiotic prophylaxis to prevent endocarditis before gastrointestinal or genitourinary procedures is no longer recommended for any patient with valvular disease. Cardiac stress test is useful in identifying individuals that may be best suited for surgical intervention. Radionuclide angiography is recommended and useful when the systolic wall stress is calculated and combined to the results.
In those with aortic rupture of the AAA, treatment is immediate surgical repair. There appears to be benefits to allowing permissive hypotension and limiting the use of intravenous fluids during transport to the operating room.
A surgical treatment for AI is aortic valve replacement; this is currently an open-heart procedure. In the case of severe "acute" aortic insufficiency, all individuals should undergo surgery, if there are no absolute contraindications (for surgery). Individuals with bacteremia with aortic valve endocarditis should not wait for treatment with antibiotics to take effect, given the high mortality associated with the acute AI. Replacement with an aortic valve homograft should be performed if feasible.
In adults and children found to have coarctation, treatment is conservative if asymptomatic, but may require surgical resection of the narrow segment if there is arterial hypertension. The first operations to treat coarctation were carried out by Clarence Crafoord in Sweden in 1944. In some cases angioplasty can be performed to dilate the narrowed artery, with or without the placement of a stent graft.
For fetuses at high risk for developing coarctation, a novel experimental treatment approach is being investigated, wherein the mother inhales 45% oxygen three times a day (3 x 3–4 hours) beyond 34 weeks of gestation. The oxygen is transferred via the placenta to the fetus and results in dilatation of the fetal lung vessels. As a consequence, the flow of blood through the fetal circulatory system increases, including that through the underdeveloped arch. In suitable fetuses, marked increases in aortic arch dimensions have been observed over treatment periods of about two to three weeks.
The long term outcome is very good. Some patients may, however, develop narrowing (stenosis) or dilatation at the previous coarctation site. All patients with unrepaired or repaired aortic coarctation require follow up in specialized Congenital Heart Disease centers.
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.
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.
Treatment consists of open heart surgery soon after birth. Awaiting surgery, prostaglandin can be administered to keep the ductus arteriosus open, thereby allowing blood flow to the lower body. Failure to treat the condition yields a mortality rate of 90% at a median age of 4 days.
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.
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.
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.
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:
Neonates without adverse symptoms may simply be monitored as outpatients, while symptomatic PDA can be treated with both surgical and non-surgical methods. Surgically, the DA may be closed by ligation (though support in premature infants is mixed), either manually tied shut, or with intravascular coils or plugs that leads to formation of a thrombus in the DA.
Devices developed by Franz Freudenthal block the blood vessel with woven structures of nitinol wire.
Because prostaglandin E2 is responsible for keeping the DA open, NSAIDS (which can inhibit prostaglandin synthesis) such as indomethacin or a special form of ibuprofen have been used to initiate PDA closure. Recent findings from a systematic review concluded that, for closure of a PDA in preterm and/or low birth weight infants, ibuprofen is as effective as Indomethacin. It also causes fewer side effects (such as transient renal insufficiency) and reduces the risk of necrotising enterocolitis. Another recent review showed that paracetamol may be effective for closure of a PDA in preterm infants.
More recently, PDAs can be closed by percutaneous interventional method (avoiding open heart surgery). A platinum coil can be deployed via a catheter through the femoral vein or femoral artery, which induces thrombosis (coil embolization). Alternatively, a PDA occluder device , composed of nitinol mesh, is deployed from the pulmonary artery through the PDA.
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 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.