Bicuspid Aortic Valve Disease Diagnosis and Complications (archived)
Bicuspid aortic valve (BAV) affects 1 to 2 percent of the general population and is one of the most common congenital heart disorders (arises during fetal development) affecting both the aortic valve and thoracic aorta.1 The normal aortic valve consists of three cusps or leaflets (tri-leaflet) that regulate oxygen-rich blood flow from the left ventricle to the aorta—major blood vessel that carries blood away from the heart. For patients with bicuspid aortic valve, their aortic valves are comprised of only two cusps (bi-leaflet) instead of three.
Diagnosis and Complications of Bicuspid Aortic Valve
A great majority of patients with bicuspid aortic valve have no symptoms. The initial diagnosis may be suspected from hearing a heart murmur on physical examination. A heart murmur is an abnormal sound caused by turbulent blood flow across a diseased valve. The murmur may be caused from:
- Aortic stenosis (valve does not open wide enough—restricted)
- Aortic regurgitation/insufficiency (valve does not close completely—leaky)
When the valve becomes restricted or leaky, patients may experience the following symptoms:
- Shortness of breath
An echocardiogram (test that uses sound waves to create a moving picture of the heart) is the most accurate way to determine whether a complication of bicuspid aortic valve, like aortic stenosis or regurgitation, is present.
Once a complication is recognized, the patient should be educated about the potential for:
- Aortic stenosis - aortic valve opening does not open wide enough, causing restricted blood flow
- Aortic regurgitation/insufficiency - aortic valve does not close completely, causing the valve to leak
- Infective endocarditis - infection of the lining of the heart chambers and heart valves
- Aortic root aneurysm - ballooning of the vessel wall at the very first portion of the aorta that is connected to the heart
- Ascending aortic aneurysm - ballooning of the vessel wall in the first part of the aorta—major blood vessel that carries blood away from the heart
- Coarctation of the aorta - narrowing of the aorta at some point along the aorta
- Aortic dissection - bleeding into and along the wall of the aorta
Aortic Stenosis and Aortic Regurgitation
With aortic stenosis and aortic regurgitation the heart weakens as it struggles to perform efficiently against a valve that is not working properly. No medical therapy will specifically relieve the restrictive or leaky valve as these are mechanical problems with the valve.
For patients with aortic stenosis and/or insufficiency that are asymptomatic (without symptoms) medical management, through close cardiac follow-up with a physician, is directed at:
- Patient education
- Slowing disease progression
- Preventing disease complications
- Prompt recognition of symptom onset
- Identifying optimal timing of surgical intervention
Patient education should stress:
- Good dental hygiene, including antibiotic prophylaxis prior to dental procedures
Once the patient with bicuspid aortic valve becomes symptomatic (with symptoms), surgical intervention is needed to prolong life and relieve symptoms. Once symptoms appear, continued medical management without surgical intervention is appropriate only for those patients who are too high-risk for surgical intervention. Prompt aortic valve replacement is the optimal treatment for severe symptomatic aortic stenosis and/or aortic regurgitation/insufficiency and further attempts at medical management alone should not delay surgical intervention.
Endocarditis is an infection of the heart that affects the heart valves and the endocardium (inside lining of the heart). Because endocarditis is a severe infection that is difficult to treat and potentially life threatening, it is important that all possible steps are taken to prevent it. Individuals with existing abnormalities of the heart, including bicuspid aortic valve and heart valve replacement, are at increased risk for developing endocarditis. Although several different organisms can cause endocarditis, it is usually caused by bacteria.
Bacteria can enter our blood on any given day. For example, bacteria may be introduced to the body during a dental or medical procedure. To combat the threat of infection, the body has elaborate and effective defense mechanisms in place. One of the defense mechanisms of the healthy heart is its smooth and continuous surface which prevents the bacteria from attaching and multiplying. If a large number of bacteria enter the bloodstream in the presence of a heart valve abnormality, the bacteria can attach to the area of deformity and begin to multiply, potentially resulting in endocarditis.
The multiplying bacteria of endocarditis can form "vegetations" on the valve they infect. These vegetations are often only lightly attached to the valve, and may emboli (break off) into the blood stream. These emboli then can act like clots, blocking flow in the arteries where they travel. Furthermore, as the vegetations travel they can spread the infection to multiple places in the body.
A person with endocarditis may have only vague and mild symptoms which may be ignored by the patient or misdiagnosed by the healthcare practitioner. On the other hand, if the infecting bacteria are aggressive, the patient may be severely ill from the onset. Symptoms may include:
- Weakness, achiness
- Fever, chills
- Sore throat
- Rapid and/or irregular heartbeat
- Shortness of breath
- Persistent cough
Oral antibiotics may not be sufficient to adequately treat endocarditis and intravenous antibiotic therapy may be required for 4 to 6 weeks, or more. Severe cases of endocarditis may require surgical replacement of the infected valve(s).
For patients with bicuspid aortic valve, as with any cardiac valve disease, antibiotic treatment for the prevention of infection is extremely important and must be taken seriously. It is well documented in the American Heart Association's Prevention of Infective Endocarditis that antibiotic treatment is required prior to any invasive procedure including teeth cleaning, breast biopsy, removal of an ingrown toenail, wart removal, hernia repair, or an angiogram/heart catheterization. The patient's cardiac healthcare practitioner should be contacted with any questions prior to any invasive procedures.
Disorders of the Aortic Wall
Bicuspid aortic valve is also associated with disorders of the aortic wall, including aortic root aneurysm, ascending aortic aneurysm, coarctation of the aorta and aortic dissection.
For patients with bicuspid aortic valve, disorders of the aortic wall occur at a significantly higher rate and occur earlier in life than individuals with a tri-leaflet aortic valve. Timely surgical intervention for patients affected with disorders of the aortic wall is critical to the longevity of the patient with bicuspid aortic valve. Disorders of the aortic wall can occur in a normally functioning bicuspid aortic valve, with a bicuspid aortic valve that is stenotic or regurgative, and may also occur late in follow-up after aortic valve replacement. Therefore, the size and shape of the aorta should be closely managed after bicuspid aortic valve is diagnosed and throughout the lifetime of the patient by a physician. Cardiac magnetic resonance imaging (MRI) or gated computed tomography (CT) angiogram are two tests frequently used to monitor disorders of the aorta.
Medical management with beta-blocking medication (slows the heart rate and reduces the strength of the heart beat) may be effective in slowing the progression of disorders of the aortic wall. Bicuspid aortic valve patients should avoid strenuous isometric activities such as weightlifting.
Patients with disorders of the aortic wall should know that aortic dissections occur with no symptoms and are surgical emergencies. Symptoms of an aortic dissection include chest pain, shortness of breath, stroke, abdominal pain, and leg pain. Aortic dissections are surgical emergencies and patients should immediately go to the emergency department if experiencing these symptoms.
For more information regarding bicuspid aortic valve disease and the treatments available, please contact the Bluhm Cardiovascular Institute at 1-866-662-8467 or request a first time appointment online.
In addition, a credible source of information about bicuspid aortic valve is the Bicuspid Aortic Foundation (BAF). Please visit the BAF website.
1. Am J Cardiol. 1998 Jun 15;81(12):1461-4.