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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.
Aortic valve repair or aortic valve reconstruction describes the reconstruction of both form and function of the native and dysfunctioning aortic valve. Most frequently it is applied for the treatment of aortic regurgitation. It can also become necessary for the treatment of an aortic aneurysm, less frequently for congenital aortic stenosis.
Treatment is not necessary in asymptomatic patients.
The treatment options for mitral stenosis include medical management, mitral valve replacement by surgery, and percutaneous mitral valvuloplasty by balloon catheter.
The indication for invasive treatment with either a mitral valve replacement or valvuloplasty is NYHA functional class III or IV symptoms.
Another option is balloon dilatation. To determine which patients would benefit from percutaneous balloon mitral valvuloplasty, a scoring system has been developed. Scoring is based on 4 echocardiographic criteria: leaflet mobility, leaflet thickening, subvalvar thickening, and calcification. Individuals with a score of ≥ 8 tended to have suboptimal results. Superb results with valvotomy are seen in individuals with a crisp opening snap, score < 8, and no calcium in the commissures.
Treatment also focuses on concomitant conditions often seen in mitral stenosis:
- Any angina is treated with short-acting nitrovasodilators, beta-blockers and/or calcium blockers
- Any hypertension is treated aggressively, but caution must be taken in administering beta-blockers
- Any heart failure is treated with digoxin, diuretics, nitrovasodilators and, if not contraindicated, cautious inpatient administration of ACE inhibitors
Tricuspid valve stenosis itself usually doesn't require treatment. If stenosis is mild, monitoring the condition closely suffices. However, severe stenosis, or damage to other valves in the heart, may require surgical repair or replacement.
The treatment is usually by surgery (tricuspid valve replacement) or percutaneous balloon valvuloplasty. The resultant tricuspid regurgitation from percutaneous treatment is better tolerated than the insufficiency occurring during mitral valvuloplasty.
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.
In terms of treatment for pulmonary valve stenosis, valve replacement or surgical repair (depending upon whether the stenosis is in the valve or vessel) may be indicated. If the valve stenosis is of congenital origin, balloon valvuloplasty is another option, depending on the case.
Valves made from animal or human tissue (are used for valve replacement), in adults metal valves can be used.
Mitral valvuloplasty is a minimally invasive therapeutic procedure to correct an uncomplicated mitral stenosis by dilating the valve using a balloon.
Under local anaesthetic, a catheter with a special balloon is passed from the right femoral vein, up the inferior vena cava and into the right atrium. The interatrial septum is punctured and the catheter passed into the left atrium using a "trans-septal technique." The balloon is sub-divided into 3 segments and is dilated in 3 stages. First, the distal portion (lying in the left ventricle) is inflated and pulled against the valve cusps. Second, the proximal portion is dilated, in order to fix the centre segment at the valve orifice. Finally, the central section is inflated, this should take no longer than 30 seconds, since full inflation obstructs the valve and causes congestion, leading to circulatory arrest and flash pulmonary edema.
With careful patient pre-selection, percutaneous balloon mitral valvuloplasty (PBMV) is associated with good success rates and a low rate of complications. By far the most serious adverse event is the occurrence of acute severe mitral regurgitation. Severe mitral regurgitation usually results from a tear in one of the valve leaflets or the subvalvular apparatus. It can lead to pulmonary edema and hemodynamic compromise, necessitating urgent surgical mitral valve replacement.
Other serious complications with PBMV usually relate to the technique of trans-septal puncture (TSP). The ideal site for TSP is the region of the fossa ovalis in the inter-atrial septum. Occasionally, however, the sharp needle used for TSP may inadvertently traumatize other cardiac structures, leading to cardiac tamponade or serious blood loss.
Although the immediate results of PBMV are often quite gratifying, the procedure does not provide permanent relief from mitral stenosis. Regular follow-up is mandatory, to detect restenosis. Long-term follow-up data from patients undergoing PBMV indicates that up to 70-75% individuals can be free of restenosis 10 years following the procedure. The number falls to about 40% 15 years post-PBMV.
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.
MR Imaging is best suited to evaluate patients with Shone's complex. Routine blood tests should be done prior to cardiac catheterization. The surgeons will repair the mitral valve and al the partial surgical removal of supramitral ring is done. This surgical method is preferred to the valve replacement procedure.
Classifying cardiac lesions in infants is quite difficult, and accurate diagnosis is essential. The diagnosis of Shone’s complex requires an ultrasound of the heart (echocardiogram) and a cardiac catheterization procedure, that is, insertion of a device through blood vessels in the groin to the heart that helps identify heart anatomy.
The primary goal of medications is to relieve symptoms such as chest pain, shortness of breath, and palpitations. Beta blockers are considered first-line agents, as they can slow down the heart rate and decrease the likelihood of ectopic beats. For people who cannot tolerate beta blockers, nondihydropyridine calcium channel blockers such as verapamil can be used, but are potentially harmful in people who also have low blood pressure or severe shortness of breath at rest. These medications also decrease the heart rate, though their use in people with severe outflow obstruction, elevated pulmonary artery wedge pressure, and low blood pressures should be done with caution. Dihydropyridine calcium channel blockers should be avoided in people with evidence of obstruction. For people whose symptoms are not relieved by the above treatments, disopyramide can be considered for further symptom relief. Diuretics can be considered for people with evidence of fluid overload, though cautiously used in those with evidence of obstruction. People who continue to have symptoms despite drug therapy can consider more invasive therapies. Intravenous phenylephrine (or another pure vasoconstricting agent) can be used in the acute setting of low blood pressure in those with obstructive hypertrophic cardiomyopathy who do not respond to fluid administration.
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.
The definitive treatment for Heyde's syndrome is surgical replacement of the aortic valve. Recently, it has been proposed that transcatheter aortic valve implantation (TAVI) can also be used for definitive management. Direct surgical treatment of the bleeding (e.g. surgical resection of the bleeding portion of the bowel) is only rarely effective.
Medical management of symptoms is possible also, although by necessity temporary, as definitive surgical management is required to bring levels of von Willebrand factor back to normal. In severe bleeding, blood transfusions and IV fluid infusions can be used to maintain blood pressure. In addition, desmopressin (DDAVP) is known to be effective in people with von Willebrand's disease, including people with valvular heart disease. Desmopressin stimulates release of von Willebrand factor from blood vessel endothelial cells by acting on the V2 receptor, which leads to decreased breakdown of Factor VIII. Desmopressin is thus sometimes used directly to treat mild to moderate acquired von Willebrand's disease and is an effective prophylactic agent for the reduction of bleeding during heart valve replacement surgery.
If restenosis occurs without a stent, it is usually treated with more angioplasty. Once restenosis has occurred and been treated by angioplasty, the chances of restenosis occurring again are increased by a factor of 2. This treatment is also used if restenosis occurs at either the proximal or distal end of the stent.
If restenosis occurs within a stent (also known as in-stent stenosis), it may be treated with repeated angioplasty and insertion of another stent inside the original, sometimes with a drug-eluting stent.
Over the past 5 years, ISR is preferentially treated with a drug eluting balloon, which is a balloon coated with the same anticancer drugs that prevent restenosis. The Balloon avoids the need for a double layer of metal which is used when an in-stent restenosis is treated with another stent within the original stent
Alternative treatments include brachytherapy, or intracoronary radiation. The radiation kills cells and inhibits tissue growth (similar to a patient undergoing cancer therapy).
The tumor must be surgically removed. Some patients will also need their mitral valve replaced. This can be done during the same surgery.
Myxomas may come back if surgery did not remove all of the tumor cells.
Surgical septal myectomy is an open-heart operation done to relieve symptoms in people who remain severely symptomatic despite medical therapy. It has been performed successfully since the early 1960s. Surgical septal myectomy uniformly decreases left ventricular outflow tract obstruction and improves symptoms, and in experienced centers has a surgical mortality of less than 1%, as well as 85% success rate. It involves a median sternotomy (general anesthesia, opening the chest, and cardiopulmonary bypass) and removing a portion of the interventricular septum. Surgical myectomy resection that focuses just on the subaortic septum, to increase the size of the outflow tract to reduce Venturi forces, may be inadequate to abolish systolic anterior motion (SAM) of the anterior leaflet of the mitral valve. With this limited resection, the residual mid-septal bulge still redirects flow posteriorly; SAM persists because flow still gets behind the mitral valve. It is only when the deeper portion of the septal bulge is resected that flow is redirected anteriorly away from the mitral valve, abolishing SAM. With this in mind, a modification of the Morrow myectomy termed extended myectomy, mobilization and partial excision of the papillary muscles has become the excision of choice. In people with particularly large redundant mitral valves, anterior leaflet plication may be added to complete separation of the mitral valve and outflow. Complications of septal myectomy surgery include possible death, arrhythmias, infection, incessant bleeding, septal perforation/defect, stroke.
The evaluation of individuals with valvular heart disease who are or wish to become pregnant is a difficult issue. Issues that have to be addressed include the risks during pregnancy to the mother and the developing fetus by the presence of maternal valvular heart disease as an intercurrent disease in pregnancy.
Normal physiological changes during pregnancy require, on average, a 50% increase in circulating blood volume that is accompanied by an increase in cardiac output that usually peaks between the midportion of the second and third trimesters. The increased cardiac output is due to an increase in the stroke volume, and a small increase in heart rate, averaging 10 to 20 beats per minute. Additionally uterine circulation and endogenous hormones cause systemic vascular resistance to decrease and a disproportionately lowering of diastolic blood pressure causes a wide pulse pressure. Inferior vena caval obstruction from a gravid uterus in the supine position can result in an abrupt decrease in cardiac preload, which leads to hypotension with weakness and lightheadedness. During labor and delivery cardiac output increases more in part due to the associated anxiety and pain, as well as due to uterine contractions which will cause an increases in systolic and diastolic blood pressure.
Valvular heart lesions associated with high maternal and fetal risk during pregnancy include:
1. Severe aortic stenosis with or without symptoms
2. Aortic regurgitation with NYHA functional class III-IV symptoms
3. Mitral stenosis with NYHA functional class II-IV symptoms
4. Mitral regurgitation with NYHA functional class III-IV symptoms
5. Aortic and/or mitral valve disease resulting in severe pulmonary hypertension (pulmonary pressure greater than 75% of systemic pressures)
6. Aortic and/or mitral valve disease with severe LV dysfunction (EF less than 0.40)
7. Mechanical prosthetic valve requiring anticoagulation
8. Marfan syndrome with or without aortic regurgitation
In individuals who require an artificial heart valve, consideration must be made for deterioration of the valve over time (for bioprosthetic valves) versus the risks of blood clotting in pregnancy with mechanical valves with the resultant need of drugs in pregnancy in the form of anticoagulation.
In the first stage of restenosis, administering anti-platelet drugs (called IIb/IIIa inhibitors) immediately after surgery greatly reduces the chance of a thrombosis occurring.
Drug-eluting stents are now being trialled in Europe, Canada and the USA, as well as in Asia-Pacific. These stents are coated with pharmaceuticals that inhibit tissue growth and thus reduce the risk of restenosis from scar-tissue and cell proliferation.
There has been some success with these new stents in reducing the occurrence of restenosis, with clinical studies showing an incidence rate of 5% or lower.
Although a myxoma is not cancer, complications are common. Untreated, a myxoma can lead to an embolism (tumor cells breaking off and traveling with the bloodstream), which can block blood flow. Myxoma fragments can move to the brain, eye, or limbs.
If the tumor grows inside the heart, it can block blood flow through the mitral valve and cause symptoms of mitral stenosis or mitral regurgitation. This may require emergency surgery to prevent sudden death.
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.
The treatment of choice is percutaneous balloon valvuloplasty and is done when a resting peak gradient is seen to be >60mm Hg or a mean >40mm Hg is observed.
The general purpose of the following treatment methods is to divert the flow of CSF from the blocked aqueduct, which is causing the buildup of CSF, and allow the flow to continue. Another goal of these treatments is to reduce the stress within the ventricles. Studies have not shown that either of the following treatments results in a higher IQ of the patient, and there is not statistical difference in a patient's quality of life based on treatment method. The following treatment methods are not used for aqueductal stenosis caused by tumor compression; if the obstruction is a direct result of tumor compression, CSF flow may be normalized by the surgical removal of the tumor.
Fetal aortic stenosis is a disorder that occurs when the fetus’ aortic valve does not fully open during development. The aortic valve is a one way valve that is located between the left ventricle and the aorta, keeping blood from leaking back into the ventricle. It has three leaflets that separate when the ventricle contracts to allow blood to move from the ventricle to the aorta. These leaflets come together when the ventricle relaxes.
Pulmonary valve stenosis (PVS) is a heart valve disorder in which outflow of blood from the right ventricle of the heart is obstructed at the level of the pulmonic valve. This type of pulmonic stenosis results in the reduction of flow of blood to the lungs. Valvular pulmonic stenosis accounts for 80% of right ventricular outflow tract obstruction. While the most common cause of pulmonary valve stenosis is congenital heart disease, it may also be due to a malignant carcinoid tumor. Both stenosis of the pulmonary artery and pulmonary valve stenosis are forms of pulmonic stenosis (nonvalvular and valvular, respectively). PVS was the key finding that led Jacqueline Noonan to identify the syndrome now called Noonan syndrome.
Options include:
- Medications alone (an antiplatelet drug (or drugs) and control of risk factors for atherosclerosis).
- Medical management plus carotid endarterectomy or carotid stenting, which is preferred in patients at high surgical risk and in younger patients.
- Control of smoking, high blood pressure, and high levels of lipids in the blood.
The goal of treatment is to reduce the risk of stroke (cerebrovascular accident). Intervention (carotid endarterectomy or carotid stenting) can cause stroke; however, where the risk of stroke from medical management alone is high, intervention may be beneficial. In selected trial participants with asymptomatic severe carotid artery stenosis, carotid endarterectomy reduces the risk of stroke in the next 5 years by 50%, though this represents a reduction in absolute incidence of all strokes or perioperative death of approximately 6%. In most centres, carotid endarterectomy is associated with a 30-day stroke or mortality rate of < 3%; some areas have higher rates.
Clinical guidelines (such as those of National Institute for Clinical Excellence (NICE) ) recommend that all patients with carotid stenosis be given medication, usually blood pressure lowering medications, anti-clotting medications, anti-platelet medications (such as aspirin or clopidogrel), and especially statins (which were originally prescribed for their cholesterol-lowering effects but were also found to reduce inflammation and stabilize plaque).
NICE and other guidelines also recommend that patients with "symptomatic" carotid stenosis be given carotid endarterectomy urgently, since the greatest risk of stroke is within days. Carotid endarterectomy reduces the risk of stroke or death from carotid emboli by about half.
For people with stenosis but no symptoms, the interventional recommendations are less clear. Such patients have a historical risk of stroke of about 1-2% per year. Carotid endarterectomy has a surgical risk of stroke or death of about 2-4% in most institutions. In the large Asymptomatic Carotid Surgery Trial (ACST) endarterectomy reduced major stroke and death by about half, even after surgical death and stroke was taken into account. According to the Cochrane Collaboration the absolute benefit of surgery is small. For intervention using stents, there is insufficient evidence to support stenting rather than open surgery, and several trials, including the ACST-2, are comparing these 2 procedures.
Angioplasty with or without stenting is the best option for the treatment of renal artery stenosis due to fibromuscular dysplasia.