Cardiac glycosides in heart failure

Cardiac glycoside for the treatment of chronic heart failure is used quite often.

Cardiac glycosides are a pharmacokinetic group of potent drugs. Active components of natural or artificial origin have a positive effect on the state of the myocardium, helping to restore the normal functioning of the heart. Among the most famous natural sources of glycosides were such medicinal plants as oleander, foxglove, lily of the valley.

It is impossible to prescribe drugs on your own, because they can cause complex side effects, have a number of contraindications for use.

Mechanism of action

Treatment of chronic heart failure is aimed at preventing the transition of the disease to an acute form, relieving symptoms, and improving the patient's quality of life.

It is necessary to understand the seriousness of the condition and be aware that if the recommendations of a specialist are not followed, extremely adverse consequences are possible, up to death. Heart failure is one of the most common causes of death in people over the age of 50.

Medicines that belong to the group of cardiac glycosides can affect all the functions of the heart muscle, helping to improve its work:

1. The active components of drugs through the stomach enter the bloodstream, then they bind to plasma proteins.
2. After taking the drug, the period of contraction of the ventricles is shortened, the rest period is lengthened.
3. This helps to achieve normalization of the heart rhythm, stabilization of blood pressure.

The mechanism of action of drugs is based on the ability of active components to influence ion channels. The expressiveness and duration of the positive effect depends on the dosage of the drug, its concentration in the blood.

Using cardiac glycosides in chronic heart failure, you can achieve the following effects:

• in the cells of the heart muscle, the concentration of calcium increases;
• there is additional stimulation of the vagus nerve;
• the impulse that is conducted along the atrioventricular junction slows down.

As a result of taking cardiac glycosides, not only positive, but also negative effects can occur, for example, a violation of the rhythm of ventricular contraction. However, such reactions are observed in case of overdose.

Classification of cardiac glycosides

The list of drugs that belong to the group of cardiac glycosides is quite wide. There is no single medical classification of drugs.

Drugs are divided into different categories according to the following criteria:

• release form;
• the concentration of the active substance;
• origin;
• duration of action.

It is important to bear in mind that medicinal plants from which cardiac glycosides are extracted, used in the treatment of chronic heart failure, are poisonous. These can be cultures found on the territory of Russia, or exotic species, for example, Greek obynik, shrub harg, African strophanthus.

These are, for example, drugs that contain glycosides isolated from bitter almonds or apricot kernels. Under the influence of special enzymes, glycosides can release hydrocyanic acid, a substance that is very dangerous for human life and health. Only 0.05 gr. - lethal dose.

Long-acting drugs

In the treatment of chronic heart failure, it is advisable to use drugs whose effect lasts for several days or even weeks. These are long-acting agents that remain in the body for a long time, retaining their effectiveness, are slowly excreted, and have the ability to accumulate.

Medicines from this category help to achieve the following results:

• the heartbeat slows down, which helps to reduce the load on the organ pumping blood;
• the contractile function of the myocardium is normalized, it begins to pump blood better, preventing its stagnation;
• normalizes blood pressure with hypertension, which is considered one of the most common causes of chronic heart failure syndrome.

The exposure time of the drug depends on the form of its release. Injections act faster, positive changes in the functioning of the heart muscle can be observed already an hour and a half after the injection. The tablets begin to act when there is a maximum concentration of active substances in the blood, this can be 8-12 hours after taking the medicine. The most popular long-acting cardiac glycosides are Cordigit, Digitoxin. The active substances are synthesized from the digitalis medicinal plant.

Average duration of action

Adonis and foxglove are used in the manufacture of medicines characterized by an average duration of action. The clinical effect occurs 5 hours after taking the drugs, lasts up to three days.

The most popular drugs from this group include:

1. Lantoside. A modern preparation of natural origin. The active ingredient is a cardiac glycoside synthesized from woolly foxglove. It is prescribed in the treatment of chronic insufficiency, which is accompanied by a violation of the rhythm of heart contractions, atrial fibrillation. The medicine is available in the form of drops.
2. Meproscillarin. The drug is available in the form of tablets, which are used for chronic insufficiency, even if it is accompanied by atrial fibrillation. The main active ingredient is a cardiac glycoside obtained by synthesizing sea onions. The effect of the drug is as follows:

• normalization of venous pressure;
• removal of puffiness;
• slowing down the heart rate.

After taking medium-acting cardiac glycosides, various side effects may occur. Do not take medicines in case of hypersensitivity to active ingredients.

Emergency help

When you need to act immediately, use the so-called emergency drugs. Such drugs are produced only in the form of a solution for injection. A positive effect occurs after 5-15 minutes, lasts throughout the day. Glycosides, which are part of drugs, do not have a cumulative effect. To obtain active substances, lilies of the valley and strophanthus are used. First, a large dose is introduced, then it is gradually reduced.

The therapeutic effect of the use of fast-acting drugs in the treatment of chronic insufficiency is as follows:

• stabilizes high blood pressure;
• the heart rate is normalized;
• tissue swelling is eliminated;
• stagnation is reduced;
• the general condition of the patient improves.

This category includes such drugs as Strofantin K, Korglikon, Korotrop. Adverse reactions after administration of short-acting drugs are almost the same as after the use of conventional cardiac glycosides. In case of an overdose, it is advisable to use potassium preparations.

Indications and contraindications

Treatment of chronic heart failure begins with the appointment of minimal doses of glycosides.

In people with dysfunction of the heart muscle, such drugs will help eliminate stagnation, as well as reduce the intensity of external manifestations. Hemodynamic parameters improve already a few days after the start of the course, while swelling and shortness of breath are eliminated, the skin becomes normal in color.

Cardiac glycosides are among those drugs that can cause severe intoxication of the body.

They are not prescribed to patients with diagnoses such as:

• hyperkalemia;
• atrioventricular block;
• extrasystole;
• severe damage to the kidneys and liver;
• stenosis.

Contraindications may not apply to all glycosides, but only to some. In any case, the doctor who treats chronic insufficiency must choose alternative options.

When prescribing certain drugs, it is necessary to take into account the following indicators:

• patient's age;
• patient's weight;
• whether there is atrial arrhythmia;
• how do the kidneys cope with the filtering functions;
• what diseases the person has.

It is erroneous to assume that the more a person weighs, the greater the dose he needs. Cardiac glycosides do not have the ability to accumulate in adipose tissue, their action is focused on the tissues of the heart muscle, so weight has little effect on determining the dosage, but should be taken into account when prescribing general therapy.

Overdose and side effects

Medicines from the group of cardiac glycosides are characterized by increased physiological activity, but they are very toxic due to the content of poisonous plant extracts. Despite this, cases of intoxication are extremely rare. This is more the exception than the rule.

The same factors can cause the development of side effects:

• cardiac disorders (hyperkalemia, tachycardia, bradycardia);
• deterioration of the urinary system;
• decrease in diuresis;
• indigestion, loss of appetite, sudden weight loss up to anorexia;
• irritability, nervous overexcitation;
• decrease in working capacity;
• general weakness.

As a result of intoxication of the body with cardiac glycosides, a lethal outcome is possible. The active components of the drugs in high concentrations contribute to the occurrence of ventricular fibrillation, exacerbation of heart failure.

In case of an overdose, you must immediately call an ambulance. Until the team arrives, you should take several tablets of activated charcoal, a laxative. To normalize the patient's condition in a medical institution, he is given a gastric lavage, prescribed medication, the action of which is aimed at normalizing the work of the heart.

List of drugs

In the assortment of pharmacy kiosks there are dozens of names of drugs that can be attributed to the pharmacokinetic group "cardiac glycosides". For the treatment of chronic insufficiency, you can use only those drugs that have been prescribed by your doctor.

There is a list of the most popular drugs from the group of glycosides:

1. Dilacor is made on the basis of woolly foxglove extracts. The drug has a mild effect, has a minimal list of contraindications, rarely leads to intoxication. The drug is indicated for the treatment of cardiac disorders, even in children of childhood.
2. Digitoxin is one of the most popular drugs. It has proven itself in the treatment of chronic insufficiency. The drug is made on the basis of foxglove purpurea, provides a longer effect than other drugs from this group. You can take Digitoxin only as directed by your doctor. As a result of the reception, heart rhythm disturbances and an increase in intraocular pressure may occur.
3. Strophanthin is a potent glycoside, which contains extracts of a tropical plant. The drug is produced in the form of a solution for injection, provides a lasting positive effect.
4. Korglikon based on May lily of the valley has calming properties, positively affects the state of the nervous system. The medicine belongs to emergency drugs, used in the treatment of acute forms of heart failure.

Complex, properly selected therapy for violation of the functioning of the heart muscle will help improve the quality of life of the patient. The action of drugs from the group of glycosides is aimed at eliminating symptoms, congestion, and normalizing the work of the heart. With timely treatment to a medical institution and compliance with all the recommendations of the attending physician, the risk of complications is significantly reduced, and the patient's life expectancy is increased.