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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.
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 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).
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.
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.
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.
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%.
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.
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.
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.
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.
The condition was initially thought untreatable until surgeon Alfred Blalock, cardiologist Helen B. Taussig, and lab assistant Vivien Thomas at Johns Hopkins University developed a palliative surgical procedure, which involved forming a side to end anastomosis between the subclavian artery and the pulmonary artery. This first surgery was depicted in the film "Something the Lord Made". It was actually Helen Taussig who convinced Alfred Blalock that the shunt was going to work. This redirected a large portion of the partially oxygenated blood leaving the heart for the body into the lungs, increasing flow through the pulmonary circuit, and greatly relieving symptoms in patients. The first Blalock-Thomas-Taussig shunt surgery was performed on 15-month-old Eileen Saxon on November 29, 1944 with dramatic results.
The Potts shunt and the Waterston-Cooley shunt are other shunt procedures which were developed for the same purpose. These are no longer used.
Currently, Blalock-Thomas-Taussig shunts are not normally performed on infants with TOF except for severe variants such as TOF with pulmonary atresia (pseudotruncus arteriosus).
Most cases do not need treatment and heal at the first years of life. Treatment is either conservative or surgical. Smaller congenital VSDs often close on their own, as the heart grows, and in such cases may be treated conservatively.
Some cases may necessitate surgical intervention, i.e. with the following indications:
1. Failure of congestive cardiac failure to respond to medications
2. VSD with pulmonic stenosis
3. Large VSD with pulmonary hypertension
4. VSD with aortic regurgitation
For the surgical procedure, a heart-lung machine is required and a median sternotomy is performed. Percutaneous endovascular procedures are less invasive and can be done on a beating heart, but are only suitable for certain patients. Repair of most VSDs is complicated by the fact that the conducting system of the heart is in the immediate vicinity.
Ventricular septum defect in infants is initially treated medically with cardiac glycosides (e.g., digoxin 10-20 µg/kg per day), loop diuretics (e.g., furosemide 1–3 mg/kg per day) and ACE inhibitors (e.g., captopril 0.5–2 mg/kg per day).
Surgical operations to assist with hypoplastic left heart are complex and need to be individualized for each patient. A cardiologist must assess all medical and surgical options on a case-by-case basis.
Currently, infants undergo either the staged reconstructive surgery (Norwood or Sano procedure within a few days of birth, Glenn or "Hemi-Fontan procedure" at 3 to 6 months of age, and the Fontan procedure at 1 1/2 to 5 years of age) or cardiac transplantation. Current expectations are that 70% of those with HLHS will reach adulthood. Many studies show that the higher the volume (number of surgeries performed) at a hospital, the lower the mortality (death) rate. Factors that increase an infant's risk include lower birth weight, additional congenital anomalies, a genetic syndrome or those with a highly restrictive atrial septum.) For patients without these additional risk factors, 5 year survival now approaches 80%. Further, studies show that about 50% of those children who survived surgery in the early development of staged reconstruction have developmental delay or need special education; about 25% of these surgical survivors have severe disabilities. There is growing evidence that while the incidence of developmental and behavioral disabilities continues to be higher than that in the general population, children operated upon in the more current era have shown significantly better neurological outcomes. An alternative to the traditional Norwood is the Hybrid procedure.
Some physicians offer "compassionate care", instead of the surgeries, which results in the child's death, usually within 2 weeks of birth. Compassionate care is overseen by a physician, and may be carried out either in the hospital or at home. However, due to the vast improvement of surgical intervention, with many hospitals achieving over 90% survival, there is debate on whether or not "compassionate care" should still be offered to families. A study in 2003 concluded that a selection of physicians who are experts in the care of children with HLHS were evenly split when asked what they would do if their own children were born with HLHS, with 1/3 stating that they would choose surgery, 1/3 stating that they would choose palliative (compassionate) treatment without surgery, and 1/3 stating that they are uncertain which choice they would make.
The three-stage procedure is a palliative procedure (not a cure), as the child's circulation is made to work with only two of the heart's four chambers.
Complete vascular rings represent about 0.5-1% of all congenital cardiovascular malformations. The majority of these are double aortic arches.
There is no known gender preference, i.e. males and females are about equally affected. There is also no known ethnic or geographic disposition.
Associated cardiovascular anomalies are found in 10-15% of patients. These include:
- Atrial septal defect (ASD)
- Ventricular septal defect (VSD)
- Patent ductus arteriosus (PDA)
- Tetralogy of Fallot (ToF)
- Transposition of the great arteries (D-TGA)
Tet spells may be treated with beta-blockers such as propranolol, but acute episodes require rapid intervention with morphine or intranasal fentanyl to reduce ventilatory drive, a vasopressor such as phenylephrine, or norepinephrine to increase systemic vascular resistance, and IV fluids for volume expansion.
Oxygen (100%) may be effective in treating spells because it is a potent pulmonary vasodilator and systemic vasoconstrictor. This allows more blood flow to the lungs by decreasing shunting of deoxygenated blood from the right to left ventricle through the VSD. There are also simple procedures such as squatting and the knee chest position which increase systemic vascular resistance and decrease right-to-left shunting of deoxygenated blood into the systemic circulation.
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.
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.
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.
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.
When treated early, that is, before the onset of pulmonary hypertension, a good outcome is possible in patients with Shone’s syndrome. However, other surgical methods can be employed depending upon the patient’s medical background. The single most important determinant of poor outcome during the surgical management of patients with Shone's syndrome is the degree of involvement of the mitral valve and the presence of secondary pulmonary hypertension.
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.