General Illness Information
Common Name:
AORTIC STENOSIS
Medical Term: None Specified
Description: Aortic stenosis is a heart condition where the aorta (the artery taking blood from the heart to the rest of the body) is constricted at the aortic valve (the valve that prevents backflow of blood from the aorta into the heart). This results in the body receiving a much-reduced supply of oxygenated blood. Also, the heart must work harder to pump the oxygenated blood out of this constricted region to the body, and in doing so gets larger and is subjected to larger pressures.
These larger pressures in the heart cause a reduction in the coronary blood flow (blood supply to the heart tissue) which may result in angina (chest pain) and palpitations (a sporadic fluttering sensation in the chest).
Causes:
Usually it is a congenital condition (i.e. one is born with it) due to malformations of the aortic valve which leads to degeneration of the valve and stenosis (constriction)
Aortic stenosis can also be an acquired condition due to:
- Degenerative calcific AS (the most common acquired cause for AS) due to the normal wear and tear of this heart valve
- Rheumatic disease.
Prevention:
- Treatment of streptococcal infections with antibiotics (i.e. rheumatic disease prevention).
- Proper prenatal care to avoid congenital birth defects such as congenital AS.
Aortic valve progression rate
Mild aortic stenosis (aortic valve opening area -1.2 – 2 cm2) becomes severe, requiring aortic valve replacement, in 10 years – in 10% of patients, in 25 years – in 38%;
Moderate asymptomatic aortic stenosis (aortic valve opening area – 0.75 – 1.2 cm2), aortic valve replacement after 10 years is required in 25% of cases;
Asymptomatic severe aortic stenosis (aortic valve opening Signs & Symptoms
- Fainting (syncope) especially on exertion.
- Fatigue.
- Chest pain (angina).
- Shortness of breath on exertion (exertional dyspnea).
- Shortness of breath on lying down (paroxysmal nocturnal dyspnea/orthopnea).
- Shortness of breath or smothering sensations.
- Swelling of the ankles (peripheral edema and congestive heart failure).
- Palpitations (sensation of heart beating irregularly/fluttering in chest).
- Vibration over the artery in the neck (carotid thrill).
- Vibration on the front of the chest on the right hand side by the breastbone and 2nd rib (systolic thrill in 2nd Right intercostal space +/- along left lower sternal border).
- Heart murmur (systolic ejection murmur loudest over the 2nd Right intercostal space).
- Changes in the heart sounds (paradoxical splitting of the second heart sound in severe cases, S4 heard in early disease, S3 heard in late disease).
Risk Factors
- Rheumatic disease
- Streptococcal infection/scarlet fever
- Other congenital heart defects
- Age >70 years old
Diagnosis & Treatment
General Measures:
Investigations for AS are as follows:
- 12 lead electrocardiogram (ECG) may show heart enlargement and strain (Left ventricular hypertrophy +/- Left Bundle Branch Block and Atrial fibrillation).
- Chest Xray may show calcification of the aortic valve widening of the aorta beyond the point of constriction (post-stenotic aortic root dilatation)and heart enlargement (Left Ventricular Hypertrophy +/- Left Atrial Enlargement).
- Echocardiography will show the difference in pressures between the heart and the aorta (pressure gradients) helping to assess the severity of the AS. Also shows the size of various chambers of the heart (Left ventricular hypertophy). Also shows the function of the pumping ability of the heart (left ventricular function). It will also how abnormalities in the aortic valve structure (leaflet abnormalities and “jet” flow across the valve).
- Cardiac Catheterization, rules out coronary artery disease (which can also present with anginal chest pain). Also used if the echocardiogram was inconclusive (i.e. confirms pressure gradients)
Shows the degree of constriction (valvular area determination) - Shows the pressures in the heart (left ventricular end diastolic pressure). Shows heart function (cardiac output) which should be normal unless there is heart dysfunction in addition to the AS (i.e. superimposed left ventricular dysfunction)
Treatment is as follows:
- Avoid heavy exertion
- Elevate the head of the bed (i.e. with pillows) to improve shortness of breath symptoms at night
- See your physician regularly to be followed with ecgs
- If severe AS (as determined by echocardiogram) avoid certain drugs (i.e. nitrates and vasodilators)
- Treat heart failure if present
- Symptomatic patients treatment is surgical (i.e. balloon valvuloplasty/ aortic valve replacement)
Aortic Valve Replacement
Aortic valve replacement can be conducted in two ways:
- Open heart;
- Minimally invasive method.
Modern cardiac surgery actively uses methods that allow prosthetic heart valves without chest incision. An operation without an incision will cost more than a classic open one. This approach reduces the likelihood of risks, facilitates the recovery period. It can be reached through an artery in the shoulder or leg area using a catheter. Local or general anesthesia is required, the total time of the operation with a catheter is about 1-1.5 hours.
Cavity surgery with a chest incision lasts longer and is less expensive than minimally invasive surgery. During valve replacement, the patient is connected to an artificial circulatory system. The risk for the patient is slightly higher than with the endoscopic method, but there is no risk of the conducting vessels’ deformation.
Medications:
- None, for treatment of the actual stenosis.
- Prophylactic antibiotics when necessary, for minor surgical procedures such as dental procedures.
- Complications such as heart failure treated with appropriate cardiac medications.
- Some medications, such as beta blockers, vasodilators may be potentially hazardous, and should be used with caution.
Activity:
Vigorous physical activity is not advisable.
Diet:
Salt restriction in congestive heart failure.
Possible Complications:
There is a slightly increased incidence in breakdown of blood cells (hemolysis), bleeding in the gastrointestinal tract, splitting of the aortic vessel wall (aortic dissection).
Prognosis
- Asymptomatic patients have excellent survival (near that of the normal population).
- Symptomatic patients have a high mortality if not treated
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