The most common cause of left atrial dilatation is systolic dysfunction. This process is expressed in a decrease in the ability of the left ventricle to throw blood from its cavity into the aorta. As a result, dilatation of the left atrium causes an increase in the final systolic volume of the left ventricle. In the event that such a compensatory reaction becomes untenable, secondary venous pulmonary hypertension may occur. Atrial dilatation in combination with pulmonary arterial hypertension increases the load on the right ventricle, the stroke volume of which decreases. An increase in diastolic pressure of the right atrium and ventricle causes venous hyperemia.
Dilation of the heart is an increase in the entire volume of the organ. The stretched myocardium becomes thinner, but if hypertrophy occurs, then these two processes cancel each other out. Papillary muscles of the cavity are also stretched, trabecular muscles are significantly flattened. Dilatation of the left atrium causes the expansion of the atrioventricular opening, which in some cases leads to functional failure. Due to stretching, the left ventricle begins to be pushed into the cavity of the right ventricle, as a result of which its volume decreases.
Dilatation of the left atrium in compensatory processes plays the same role as adaptations in a healthy heart. If a diseased heart does not have sufficient strength to overtake the right amount of blood, then by increasing the length of the fibers, it becomes able to perform this work. However, this reduces the reserve power of the myocardium due to an increase in the amount of work and a large demand for oxygen. Persons with dilatation must observe a gentle regime, since any even the most insignificant work is carried out at the expense of spare heart forces. Dilation is a fairly common syndrome and the cause of heart failure. The disease can be infectious and toxic in nature. The most common cause of dilatation is alcohol damage to the heart. The reason is also autoimmune and neuromuscular diseases, as well as mitochondrial, endocrine and metabolic disorders in the patient's body.
As a rule, dilation develops at a young age, more often in men. Clinical manifestations are expressed in the form of total heart failure, cardialgia, cardiac arrhythmias, angina pectoris, thromboembolism. The clinic of the disease is not specific. The patient may suddenly die due to the progression of heart failure or due to rhythm disturbances. With the disease, systolic murmur is often found in relation to tricuspid and mitral insufficiency. Edematous syndrome and swelling of the cervical veins are also observed.
The main diagnostic method is echocardiography and scintigraphy. You can also get useful information using stress tests and differential diagnostics.
In the treatment of dilatation, exactly the same therapy is used as with heart failure, since etiotropic therapy is possible only with a known etiology. Recommend limiting fluid intake, adequate
physical activity, control of diuresis. It is strictly forbidden to receive even
small doses of alcohol. With the development of cardiac cachexia, nutritional, that is, nutritional support, is of great importance. For drug treatment, beta-blockers are mainly used. The use of thiazide and loop diuretics is shown, while diuresis control is mandatory. In combination with diuretics, aldosterone antagonists are used.