VERIFIED CONTENTAuthor: lek. Maciej Grymuza, a graduate of the Faculty of Medicine at the Medical University of K. Marcinkowski in Poznań.

Aortic stenosis is a valve disease of the heart that significantly increases the workload on the heart and reduces blood flow to the arteries. What exactly is the narrowing of the aortic valve of the heart, what conditions does it cause and what are the treatment methods?

Aortic valve stenosis(aka aortic stenosis, stenosis of the left arterial outlet) is the most common valvular heart disease. Among heart diseases, only arterial hypertension and ischemic heart disease are more common. Depending on the extent of the defect, aortic stenosis is of three types: mild, moderate and severe. Aortic valve stenosis especially affects the elderly. It is estimated that over 5% of people over 75 have this defect.

If aortic stenosis is diagnosed in a timely manner, the attending physician, together with other members of the so-called The heart of the team (a team consisting of an interventional cardiologist and a cardiac surgeon) decide on the coercion of the defect and how to carry it out. There are 2 basic treatments for aortic stenosis surgery - classical surgery and minimally invasive implantation (TAVI). Both allow for many years of survival after such an intervention.

Aortic valve - structure, role, stenosis

The aortic valve is located between the left ventricle and the aorta. It is through her that blood is thrown out during each contraction of the heart. The aortic valve is made of a ring and 3 crescent-shaped petals.

The role of the aortic valve is primarily to prevent the flow of blood from the aorta as the heart relaxes, where the pressure in the left ventricle drops. As the heart contracts, the valve petals open and blood flows into the aorta. In turn, when the heart relaxes, the valve closes by filling the petals with a small amount of blood flowing back from the aorta. In normal conditions, the junction of the left ventricle and aorta, i.e. the left arterial opening, has a shape similar to a circle, and the surface area of ​​the opening through which blood is ejected measures approx. 2.5-3.5 cm².

For narrowing of the aortic valve, i.e. reducing its areasurface can occur for many reasons, such as damage, wear and tear, or other diseases. This results in an increase in the resistance to the outflow of blood, i.e. there is an increase in the so-called afterload, which in turn translates into the need to increase the work performed by the beating heart and extend the time of blood ejection - opening the valve.

In the long run, such increased work, as with any muscle, leads to left ventricular wall hypertrophy. The result, in turn, is a disturbance of the proportion between the work of the heart - muscle contraction and the increase in pressure inside it. This leads to impaired contractility of the heart muscle and a decrease in the volume of blood ejected. Moreover, the thickened muscle does not relax effectively, leading to improper filling of the chamber with blood during diastole.

All these processes related to valve stenosis not only lead to the symptoms of this disease described below, but also predispose to atrial fibrillation or ischemic heart disease.

The development of aortic stenosis takes many years, so changes in the functioning of the aortic valve and the entire heart appear over time.

Aortic stenosis - causes

The most common factors contributing to the formation of aortic stenosis are:

  • age - this defect usually occurs in the elderly and is most often caused by a degenerative process, i.e. valve wear,
  • sex - the defect is more common in men than in women,
  • smoking,

and chronic diseases such as:

  • hypertension,
  • diabetes,
  • kidney failure,
  • overweight and obesity,
  • disturbances in the amount of lipids in the blood (cholesterol) - this process is characterized by calcification of the valve, especially at the edges of the petals.

Aortic valve stenosis is much less often caused by rheumatic disease, i.e. autoimmune valve damage that is a complication of pharyngitis caused by streptococci. In rheumatic disease, the flakes fuse together, become scarred and calcified, as a result of which they do not open properly and the surface of the mouth becomes smaller.

The least common cause of aortic valve stenosis is a congenital defect - the so-called two-leaflet valve.

Aortic stenosis - symptoms

Aortic stenosis is a dangerous defect, as approximately 50% of patients do not experience any symptoms. Especially when the narrowing is minor. This asymptomatic condition can last for many years. As it risesstrictures, however, symptoms begin to appear that indicate significant damage to the heart, such as:

  • Angina symptoms , i.e. chest pains characteristic of ischemic heart disease. They result from a disturbance of the ratio between the overgrown muscle and the amount of blood supplied by the coronary vessels. The thickened wall of the left ventricle has a much greater demand for oxygen and nutrients, and the coronary arteries do not grow fast enough to meet the increased demand of the heart muscle. This results in the symptoms of ischemic heart disease, because despite the absence of atherosclerosis, what is known as relative ischemia of the heart muscle occurs.
  • Palpitations , which may be a symptom of the disease itself or of atrial fibrillation associated with it. This arrhythmia occurs when the overgrown left ventricular muscle does not relax effectively, making it difficult to fill it with blood. Despite the muscle contraction of the left atrium, less blood flows into the ventricle, resulting in atrial fibrillation.
  • " Symptoms of a small discharge ", i.e. dizziness, fainting, fatigue - they result from a small amount of blood thrown out by the narrowed valve, which causes periodic ischemia of the central nervous system.
  • Heart failure- appears as the end stage of the disease. If the defect continues and is not treated, it leads to the development of a complex of symptoms of heart failure. On medical examination, you can hear a systolic murmur over the aortic valve, which may radiate to the carotid arteries. With atrial fibrillation, the heart rate becomes irregular.

Aortic valve stenosis - diagnosis

The medical examination gives grounds to assume that the patient has aortic stenosis. A certain diagnosis requires additional tests, in particular:

  • echocardiographic examination (echo of the heart)- it allows you to confirm this disease, assess the degree of its advancement, heart function and monitor the progress of the defect. It is on the basis of the parameters obtained from the echo test - the size of the valve orifice, the mean pressure gradient (pressure difference between the aorta and the left ventricle) and the velocity of blood flow through the valve, that aortic defect is classified into the group of mild, moderate and severe stenosis (valve area less than 1 cm²) ). The division and the speed of the defect growth are very important because they determine the further procedure,
  • electrocardiographic examination(EKG) , in which, in the case of an advanced defect, there are features of left ventricular hypertrophy,
  • chest X-ray , which shows the enlargement of the heart and calcification of the valves.

Cardiac echo is a key test in the diagnosis of aortic stenosis. ECG and X-ray play a marginal role because deviations in their range occur in a very advanced defect.

Invasive tests, such ascoronography , are rarely performed in the diagnosis of aortic stenosis. The indication for coronary angiography is qualification for valve surgery. The examination is performed in patients with suspected coronary atherosclerosis in order to assess the coronary vessels and possible indications for sewing by-passes during the same operation.

Aortic stenosis - treatment

Treatment methods for aortic stenosis can be divided into 2 groups:

  • conservative treatment- preferred in the case of mild and moderate stenosis and if the defect is severe but has not been qualified for invasive surgery; conservative treatment includes periodic echocardiographic control every 1-3 years depending on age, size of the defect and other factors, as well as pharmacological therapy aimed at treating heart failure, atrial fibrillation and reducing the symptoms of myocardial ischemia,
  • invasive, surgical treatment- it is undertaken in the event of symptoms of severe stenosis of the valve found in echocardiography or abnormal stress test results.

Invasive treatments in the treatment of aortic stenosis are:

  • classic cardiac surgery(basic method), during which the damaged valve is replaced in extracorporeal circulation and bypassed if necessary. Mechanical valves are usually sewn in. They are persistent, but their presence requires taking anticoagulants ("blood thinners") for the rest of their lives, and hence periodic INR monitoring. Its target values ​​depend on the type of implanted valve and are determined by the doctor performing the procedure. If the use of these drugs is contraindicated (e.g. in young women planning a pregnancy), repair surgery, implantation of a heretograft (an appropriately cleaned valve from e.g. a pig) or a homograft (i.e. a pulmonary valve and aortic valve - the so-called Ross operation). Such a solution is less durable and usually after about 10 years it is necessary to reoperate and replace the valve, but presencenatural valves does not require taking anticoagulants.
  • catheter implantation - otherwise: TAVI(transcatheter aortic valve implantation) - this procedure involves placing a new aortic valve through the femoral artery. During the procedure, the implantation site is precisely determined on the basis of a scopy, i.e. an examination with the use of X-rays and echo of the heart. The valve placed and "packed" on the catheter is deposited in a designated place. TAVI is performed in patients who, for example due to comorbidities, are disqualified from classical surgery because it would involve too high a risk. Another indication for this procedure is individual indications in people who may benefit more from transcatheter treatment (e.g. valve morphology). Of course, such a procedure also has many contraindications, such as the lack of cardiac surgery facilities at the site of the procedure or poor anatomical conditions. However, it remains an important therapeutic option for seriously ill people who suffer from many other ailments in addition to aortic stenosis. After TAVI surgery, it is usually not necessary to use anticoagulants, but the decision about their use or not is made by the doctor performing the procedure.
  • percutaneous balloon valvulotomy(a very rare method), like TAVI, is an intervention performed through the femoral artery, but dilates the stenotic valve and partially corrects the defect. it is used as a "bridging" procedure before replacement surgery when there is a high risk of immediate surgery, and less frequently to relieve symptoms temporarily. The effects of valvulotomy are not long-lasting, the stenosis usually recurs after 6-12 months.

It should be remembered that after valve replacement, regardless of whether it is a classic or TAVI method, it is necessary to prevent infectious endocarditis, consisting primarily of taking antibiotics before dental procedures and preventing, and, if necessary, appropriate treatment, bacterial infections.

Aortic stenosis - complications

Untreated aortic valve stenosis may result in deterioration of physical performance, atrial fibrillation and heart failure, but also embolism, such as stroke due to closure of the cerebral arteries by broken calcifications. What's more, it happens that bacteria can grow more easily on a damaged valve, causing infective endocarditis. It has also been proven that the tight narrowing of the aortic opening promotes coagulation disorders,since platelets and plasma proteins are damaged in this area, it is more prone to bleeding, especially from the gastrointestinal tract.

Aortic stenosis - prognosis

Until symptoms of aortic stenosis appear, the prognosis is good, patients live for many years without knowing about the disease. However, the appearance of ailments worsens the prognosis for treatment. That is why it is so important and necessary to periodically check this heart defect and see a doctor in the event of dyspnea, palpitations or chest pain. Symptoms increase the likelihood of death, but surgery increases life expectancy.

Playing sports with a narrowed aortic valve

In the case of severe aortic stenosis, playing sports should be severely limited, and in some cases even contraindicated. After treatment (surgery or TAVI), it is possible to resume sports, usually without restrictions. However, for some reasons, practicing sports may be limited. In people taking anticoagulants, it is contraindicated to engage in contact sports due to the risk of injury and the associated risk of bleeding, especially dangerous in people taking "blood thinning" drugs.

Category:

Cardiology