Treatment of heart failure

Treatment of heart failure is aimed at increasing the contractility of the myocardium, eliminating congestion (fluid retention), normalizing the functions of internal organs and homeostasis. Of course, a mandatory condition is treatment of the underlying disease that caused heart failure.

General tactics and principles of treatment of chronic heart failure

The goals of treatment for chronic heart failure are:

• elimination of disease symptoms - shortness of breath, palpitations, increased fatigue, fluid retention in the body;
• protection of target organs (heart, kidneys, brain, blood vessels, muscles) from damage:
• improving the quality of life;
• reduction in the number of hospitalizations:
• improving prognosis (extending life).

In practice, only the first of these principles is most often followed, which leads to a rapid return of decompensation and rehospitalization. The concept of "quality of life" should be defined separately. This is the patient's ability to live the same full life as his healthy peers who are in similar social, economic and climatic conditions. Changes in quality of life are not always parallel to clinical improvement. Thus, the prescription of diuretics is accompanied by clinical improvement, but the need to be "tied" to the toilet, side effects of drugs worsen the quality of life.

Physical rehabilitation of patients plays an important role in the complex treatment of patients with chronic heart failure. A sharp restriction of physical activity is justified only during the development of left ventricular failure. Outside of an acute situation, the lack of activity leads to structural changes in skeletal muscles, which themselves are changed in chronic heart failure, detraining syndrome and, subsequently, to the inability to perform physical activity. Moderate physical training (walking, treadmill, cycling - for older children), of course, against the background of therapy, allows to reduce the content of neurohormones, increase sensitivity to drug treatment and tolerance of loads, and, consequently, improve emotional tone and quality of life.

In case of heart failure of stage II B-III, strict bed rest is indicated: the child makes all movements in bed with the help of medical personnel or parents. Such a regime is necessary as a preventive measure against thromboembolic complications, especially in case of myocardial damage by the inflammatory process.

A more extended regimen is bed rest, which assumes independent movements of the child in bed. The child can read, draw, and do schoolwork for 45 minutes. This is a transitional version of the regimen, it is prescribed for stage II B heart failure, when positive dynamics appear.

Light bed rest, allowing the child to go to the toilet, playroom, and to the dining room, is prescribed for stage II A heart failure. With a tendency toward positive dynamics and a practical absence of signs of heart failure at rest, room rest is prescribed.

In addition to physical rest, the child needs to be provided with an environment that is as gentle as possible on his psyche and individual care. The best option is to place the child in a separate room with the involvement of his parents in caring for him.

Oxygen therapy is of great importance: older children can receive humidified oxygen from an oxygen system, younger children are placed in an oxygen tent.

Diet for heart failure

Nutrition for heart failure, in addition to age-related features of the set of products, suggests preferably steaming dishes, excluding extractive substances: spices, fried, strong tea, coffee, smoked meats, fatty meats, fish, caviar, etc. Limit or exclude products that contribute to the occurrence of flatulence: beans, peas, cabbage, sometimes black bread, etc. It is recommended to use more widely products containing potassium salts, such as apricots, dried apricots, prunes. With regard to potatoes, as a product rich in potassium salts, you should be more careful, since the high starch content in this product, as well as the high carbohydrate content in sweets, bakery products, contribute to a decrease in intestinal motility and lead to constipation, which can significantly worsen the condition of the patient, who is also forced to be in a state of hypodynamia. In view of this, it is advisable to prescribe fermented milk products (kefir, yogurt), as well as vegetable juices. In severe cases, the number of meals can be increased to 4-5 times or more. The last meal should be 2-3 hours before bedtime.

The amount of table salt is limited to 2-4 g/day, starting from stage II A of heart failure. At stage II B and III with pronounced edematous syndrome, a chloride-free diet can be prescribed for a short time. In addition, with pronounced edematous syndrome, fasting days are carried out 1-2 times in 7-10 days, including cottage cheese, milk, dried fruit compotes, apples, raisins (or dried apricots), fruit juice in the diet. The purpose of fasting days is to ease the work of the heart and other organs against the background of a reduced volume of food and liquid.

At the same time, while limiting certain types of foods, one should, if possible, adhere to a “cardiotrophic” diet with an increased content of complete and easily digestible protein.

The water regime requires some restrictions, starting from stage II A of heart failure, taking into account diuresis: the amount of fluid drunk and excreted. At the same time, it is necessary to remember that limiting fluid by more than 50% of the body's daily requirement does not ensure the formation of a "metabolic" amount of urine, there is a retention of toxins in the body, which contributes to the deterioration of the condition and well-being of a patient with heart failure.

Drug treatment of heart failure

In recent years, the attitude towards the treatment of heart failure has changed somewhat. Drugs are prescribed that target various links in the pathogenesis of heart failure syndrome.

Cardiac glycosides

One of the main groups of drugs is cardiac glycosides - cardiotonic agents of plant origin (foxglove, lily of the valley, sea onion, spring adonis, etc.), which have the following mechanisms of action:

• positive inotropic effect (increased myocardial contractility);
• negative chronotropic effect (slowing of heart rate);
• negative dromotropic effect (slowing of conduction);
• positive bathmotropic effect (increased activity of heterotopic foci of automatism).

Cardiac glycosides also increase glomerular filtration and enhance intestinal peristalsis.

Cardiac glycosides act on the heart muscle through a specific effect on the receptor apparatus, since only about 1% of the administered drug is concentrated in the myocardium. In the 1990s, studies appeared recommending limited use of digoxin with its replacement with non-glycoside inotropic stimulants. This practice has not received widespread use due to the impossibility of conducting long-term treatment courses with such drugs, so the only drugs that increase myocardial contractility that remain in clinical practice are cardiac glycosides. Predictors of good digoxin action are an ejection fraction of less than 25%, a cardiothoracic index of more than 55%, and a non-ischemic cause of chronic heart failure.

Cardiac glycosides can be bound to blood albumins, then they are absorbed mainly in the intestine, act more slowly (digoxin, digitoxin, isolanid) and are indicated mainly for chronic heart failure, while it turns out that digitoxin is partially converted into digoxin. In addition, digitoxin is more toxic, so digoxin is used in clinical practice. Digoxin is calculated using several methods. We indicate the method that we use in our clinical practice: the saturation dose of digoxin is 0.05-0.075 mg / kg of body weight up to 16 kg and 0.03 mg / kg of body weight over 16 kg. The saturation dose is given for 1-3 days, 3 times a day. The daily maintenance dose is 1 / 6-1 / 5 of the saturation dose, it is given in 2 doses. The prescription sheet should indicate the heart rate at which digoxin should not be given. Thus, the patient receiving digoxin is under constant medical supervision. Such a need for supervision arises due to the fact that the pharmacological properties of digoxin easily change under the influence of various factors and an individual overdose of the drug is possible. According to B.E. Votchal, "cardiac glycosides are a knife in the hands of a therapist", and the prescription of cardiac glycosides can be a clinical experiment, during which "it is necessary to persistently and painstakingly select the required dose of the most suitable cardiac glycoside in each specific case". In chronic heart failure, cardiac glycosides are prescribed already at stage II A.

Cardiac glycosides, not bound to blood proteins, act quickly and are administered intravenously. These drugs [strophanthin-K, lily-of-the-valley herb glycoside (korglikon)] are indicated primarily for acute or symptomatic heart failure (severe infections, severe somatic pathology). It should be taken into account that strophanthin-K acts directly on the AV junction, inhibiting impulse conduction, and if the dose is incorrectly calculated, it can cause cardiac arrest. Lily-of-the-valley herb glycoside (korglikon) does not have this effect, so this drug is currently preferred.

In the mid-1970s, ACE inhibitors appeared in clinical practice. The main physiological meaning of using these drugs is as follows: by blocking the activity of ACE, the administered drug of this group leads to a disruption in the formation of angiotensin II, a powerful vasoconstrictor. cell proliferation stimulator, which also promotes the activation of other neurohormonal systems, such as aldosterone and catecholamines. Therefore, ACE inhibitors have vasodilating, diuretic, antitachycardic effects and allow reducing cell proliferation in target organs. Their vasodilating and diuretic effects are further increased due to the blockade of bradykinin destruction, which stimulates the synthesis of vasodilating and renal prostanoids. An increase in bradykinin content blocks the processes of irreversible changes that occur in CHF in the myocardium, kidneys, and vascular smooth muscles. The special effectiveness of ACE inhibitors is determined by their ability to gradually block circulating neurohormones, which allows not only to influence the clinical condition of patients, but also to protect target organs from irreversible changes occurring during the progression of chronic heart failure. The use of ACE inhibitors is indicated already in the initial stages of chronic heart failure. Currently, the effectiveness (positive effect on symptoms, quality of life, prognosis of patients with chronic heart failure) and safety of four ACE inhibitors used in Russia (captopril, enalapril, ramipril, trandolapril) have been fully proven. In pediatric practice, captopril is most widely used. Non-hypotensive doses of the drug are prescribed, amounting to 0.05 mg / kg per day in 3 doses. The duration of use of the drug depends on hemodynamic indications. Side effects - cough, azotemia, hyperkalemia, arterial hypotension - occur relatively rarely.

Diuretics

From the point of view of evidence-based medicine, diuretics are the least studied drugs for the treatment of patients with chronic heart failure. This is largely due to the fact that, according to the deontological code, it is impossible to conduct placebo-controlled studies, since patients with chronic heart failure included in the control group will obviously be deprived of the opportunity to receive diuretics. When deciding on the appointment of diuretics, it is important for the doctor to overcome the stereotype that dictates the appointment of diuretics to any patient with chronic heart failure. It is necessary to firmly grasp the position that diuretics are indicated only for patients with chronic heart failure. having clinical signs and symptoms of excessive fluid retention in the body.

Diuretics promote volumetric unloading of the heart. However, caution in prescribing drugs of this group is dictated by the following provisions:

• Diuretics activate neurohormones that contribute to the progression of chronic heart failure, in particular by activating the renin-angiotensin-aldosterone system:
• Diuretics cause electrolyte disturbances.

Taking these provisions into account, diuretics cannot be classified as pathogenetically justified means of treating chronic heart failure, but they remain a necessary component of treatment. Currently, the fundamental points in prescribing diuretics have been determined: the use of diuretics together with ACE inhibitors, the prescription of the weakest of the effective diuretics for a given patient. Diuretics should be prescribed daily in minimal doses that allow achieving the necessary positive diuresis.

The practice of prescribing “shock” doses of diuretics once every few days is flawed and is difficult for patients to tolerate.

The tactics of treatment with diuretics involves two phases.

• Active phase - elimination of excess fluid, which manifests itself in the form of edema. In this phase, it is necessary to create forced diuresis with the excess of excreted urine over the consumed fluid.
• After achieving optimal dehydration of the patient, the maintenance stage of treatment is started. During this period, the amount of liquid drunk should not exceed the volume of urine excreted.

In the mechanism of action of diuretics, the main importance is given to the processes occurring in the nephron. Usually, diuretics are prescribed starting from stage II B-III of heart failure. As a rule, the prescription of powerful diuretics causing maximum natriuresis and potassium-sparing diuretics (spironolactone) is combined. Actually, spironolactone (veroshpiron) is not a very strong diuretic, it has an enhanced effect together with loop and thiazide diuretics. Spironolactone has a greater pathogenetic significance as an aldactone antagonist, i.e. as a neurohormonal modulator blocking the renin-angiotensin-aldosterone system. Spironolactone is prescribed in the first half of the day, usually in 2 doses. The main side effects may be hyperkalemia, which requires control, and the androgenic properties of the drug, which cause gynecomastia in 7-8% of cases.

Powerful diuretics include furosemide (lasix) and ethacrynic acid. Treatment begins with furosemide at a dose of 1-3 mg/kg of body weight per day in 3-4 doses. Both oral and intramuscular administration of the drug is possible. Ethacrynic acid (uregit) is used in the same cases as furosemide, especially in children with developing refractoriness who have been receiving furosemide for a long time.

Hydrochlorothiazide (hypothiazide) is classified as a moderate-acting diuretic; it is prescribed for stage II A heart failure, either alone or in combination with spironolactone; the maximum dose of hydrochlorothiazide is 1-2 mg/kg of body weight.

To replenish potassium, which is removed from the body when most diuretics are prescribed, in addition to products containing a fairly high amount of potassium salts, such drugs as potassium and magnesium aspartate (panangin, asparkam), potassium acetate (10%) are prescribed orally. It should be taken into account that the administration of potassium chloride orally is unacceptable, since this drug has an ulcerogenic effect on the mucous membrane of the gastrointestinal tract.

Diuretic treatment can be started with smaller doses and gradually increased, which allows for individual dose selection and does not cause rapid fluid loss or electrolyte disturbances. In addition, increased blood viscosity promotes thrombus formation. When the condition stabilizes, an intermittent course of diuretic treatment can be used.

It should be noted that everything said above about the appointment of diuretics is of a recommendatory nature; each individual clinical case is considered individually.

Other drugs

The use of beta-blockers for the treatment of chronic heart failure is based on the fact that they enhance the hemodynamic function of the heart with an increase in the density of beta-adrenergic receptors of the heart, which usually decreases sharply in patients with chronic congestive heart failure. It should be noted that the use of beta-blockers in children is limited by the lack of convincing data from multicenter studies, as well as the risk of decreased myocardial contractility and cardiac output in the presence of existing cardiac dysfunction.

The use of vasodilators of other groups, in particular nitrates, is currently not widely used in pediatric practice.

For the treatment of heart failure, glucocorticoids, cardiotropic drugs, vitamin complexes and membrane-stabilizing drugs can be used as indicated.

In chronic heart failure syndrome, drugs that improve the metabolic state of the myocardium are of great interest. Against this background, interest in magnesium preparations is experiencing a rebirth. Magnesium is a universal regulator of energy, plastic, electrolyte metabolism, a natural calcium antagonist. It promotes the fixation of potassium in the cell and ensures the polarization of cell membranes, thereby controlling the normal functioning of the myocardial cell at all levels, including regulating the contractility of the myocardium. Natural food sources are usually not rich in magnesium, therefore, for use in therapeutic practice, it is proposed to use a magnesium preparation - Magnerot. When it is prescribed, as experimental data have shown, the contractility of the left ventricle improves.

A distinctive feature of the drug Magnerota is that the presence of orotic acid in the structure of the molecule promotes the best, compared to other drugs, penetration of magnesium ions into the cell and fixation on the membrane of ATP. In addition, the drug does not cause or aggravate intracellular acidosis, which often occurs in heart failure. drugs are prescribed for 4-6 weeks. Since the drug does not have pronounced contraindications, and it is prescribed even during pregnancy and lactation, it is even more possible to prescribe it to children with heart failure. Doses are on average 1 tablet 2-3 times a day.