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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.
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.
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.
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).
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.
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.
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.
Aortic insufficiency or aortic regurgitation can be treated either medically or surgically, depending on the acuteness of presentation, the symptoms and signs associated with the disease process, and the degree of left ventricular dysfunction. Surgical treatment in asymptomatic patients has been recommended if the ejection fraction falls to 50% or below, in the face of progressive and severe left ventricular dilatation, or with symptoms or abnormal response to exercise testing. For both groups of patients, surgery before the development of worsening ejection fraction/LV dilatation is expected to reduce the risk of sudden death, and is associated with lower peri-operative mortality. Also, surgery is optimally performed immediately in acute cases.
Quadricuspid aortic valves are very rare cardiac valvular anomalies with a prevalence of 0.013% to 0.043% of cardiac cases and a prevalence of 1 in 6000 patients that undertake aortic valve surgery. There is a slight male predominance in all of the cases, and the mean age is 50.7.
Right-sided aortic arch is rare, with a prevalence among adults of about 0.01%.
Bicuspid aortic valves are the most common cardiac valvular anomaly, occurring in 1–2% of the general population. It is twice as common in males as in females.
Bicuspid aortic valve is a heritable condition, with a demonstrated association with mutations in the NOTCH1 gene. Its heritability (formula_1) is as high as 89%. Both familial clustering and isolated valve defects have been documented. The incidence of bicuspid aortic valve can be as high as 10% in families affected with the valve problem..Recent studies suggest that BAV is an autosomal dominant condition with incomplete penetrance. Other congenital heart defects are associated with bicuspid aortic valve at various frequencies, including coarctation of the aorta.
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.
The following table includes the main types of valvular stenosis and regurgitation. Major types of valvular heart disease not included in the table include mitral valve prolapse, rheumatic heart disease and endocarditis.
In an acute dissection, treatment choice depends on its location. For Stanford type A (ascending aortic) dissection, surgical management is superior to medical management. For uncomplicated Stanford type B (distal aortic) dissections (including abdominal aortic dissections), medical management is preferred over surgical.
The risk of death due to aortic dissection is highest in the first few hours after the dissection begins, and decreases afterward. Because of this, the therapeutic strategies differ for the treatment of an acute dissection compared to a chronic dissection. An acute dissection is one in which the individual presents within the first two weeks. If the individual has managed to survive this window period, his prognosis is improved. About 66% of all dissections present in the acute phase. Individuals who present two weeks after the onset of the dissection are said to have chronic aortic dissections. These individuals have been self-selected as survivors of the acute episode and can be treated with medical therapy as long as they are stable.
Some evidence suggests that indomethacin administration on the first day of life to all preterm infants reduces the risk of developing a PDA and the complications associated with PDA. Indomethacin treatment in premature infants also may reduce the need for surgical intervention.
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.
Right-sided aortic arch is a rare anatomical variant in which the aortic arch is on the right side rather than on the left. During normal embryonic development, the aortic arch is formed by the left fourth aortic arch and the left dorsal aorta. In people with a right-sided aortic arch, instead the right dorsal aorta persists and the distal left aorta disappears.
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.
Without life-prolonging interventions, HLHS is fatal, but with intervention, an infant may survive. A cardiothoracic surgeon may perform a series of operations or a full heart transplant. While surgical intervention has emerged as the standard of care in the United States, other national health systems, notably in France, approach diagnosis of HLHS in a more conservative manner, with an emphasis on termination of pregnancy or compassionate care after delivery.
Before surgery, the ductus must be kept open to allow blood-flow using medication containing prostaglandin. Air with less oxygen than normal is used for infants with hypoplastic left heart syndrome. These low oxygen levels increases the pulmonary vascular resistance (PVR) and thus improve blood flow to the rest of the body, due to the greater pressure difference between the lungs and body. Achieving oxygen levels below atmosphere requires the use of inhaled nitrogen. Nitric oxide is a potent pulmonary vasodilator, and thus reduces PVR and improves venous return. Any factor that increases PVR will impede right sided flow.
A device, known as the Amplatzer muscular VSD occluder, may be used to close certain VSDs. It was initially approved in 2009. It appears to work well and be safe. The cost is also lower than having open heart surgery. The device is placed through a small incision in the groin.
The Amplatzer septal occluder was shown to have full closure of the ventricular defect within the 24 hours of placement. It has a low risk of embolism after implantation. Some tricuspid valve regurgitation was shown after the procedure that could possibly be due from the right ventricular disc. There have been some reports that the Amplatzer septal occluder may cause life-threatening erosion of the tissue inside the heart. This occurs in one percent of people implanted with the device and requires immediate open-heart surgery. This erosion occurs due to improper sizing of the device resulting with it being too large for the defect, causing rubbing of the septal tissue and erosion.
Anomalous origin of the right coronary artery originating from the pulmonary trunk (ARCAPA) is a rare but potentially fatal anomaly. The goal of surgical therapy is establishment of a physiologic bi-coronary circulation.
Inflammation of the heart valves due to any cause is called valvular endocarditis; this is usually due to bacterial infection but may also be due to cancer (marantic endocarditis), certain autoimmune conditions (Libman-Sacks endocarditis, seen in systemic lupus erythematosus) and hypereosinophilic syndrome (Loeffler endocarditis). Certain medications have been associated with valvular heart disease, most prominently ergotamine derivatives pergolide and cabergoline.
Valvular heart disease resulting from rheumatic fever is referred to as "rheumatic heart disease". Damage to the heart valves follows infection with beta-hemolytic bacteria, such as typically of the respiratory tract. Pathogenesis is dependent on cross reaction of M proteins produced by bacteria with the myocardium. This results in generalized inflammation in the heart, this manifests in the mitral valve as vegetations, and thickening or fusion of the leaflets, leading to a severely compromised buttonhole valve.
Rheumatic heart disease typically only involves the mitral valve (70% of cases), though in some cases the aortic and mitral valves are both involved (25%). Involvement of other heart valves without damage to the mitral are exceedingly rare.
While developed countries once had a significant burden of rheumatic fever and rheumatic heart disease, medical advances and improved social conditions have dramatically reduced their incidence. Many developing countries, as well as indigenous populations within developed countries, still carry a significant burden of rheumatic fever and rheumatic heart disease and there has been a resurgence in efforts to eradicate the diseases in these populations.
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.
Bicuspid aortic valve abnormality is seen in 1 to 2 percent of all live births. It is associated with a number of mutations affecting Notch signalling pathway.