Antiarrhythmic drugs: classification, list of drugs for heart arrhythmia

Developed pharmacology represents an extensive line of antiarrhythmic drugs. But the species diversity of heart rhythm disturbances, the causes of their occurrence requires specific knowledge regarding the necessary means. Therefore, before prescribing and taking medications to eliminate malfunctions in the heart, it is important to familiarize yourself with the principle of action of the drugs and possible negative effects.

Classification of antiarrhythmic drugs

There are two approaches to the classification of these funds: on the localization of exposure and on the method of application in medical practice.

The first type relates directly to what the effect of the drug is directed on. Allocate drugs that act on the heart muscle, and are responsible for the provision of the heart with nerve impulses.

In the first group there are:

• membrane-stimulating drugs;
• antiarrhythmics that block calcium channels;
• magnesium sulfate;
• potassium preparations;
• agents affecting potassium channels.

In the second group, the following drugs are found:

• sympathomimetics;
• beta adrenomimetics;
• beta-blockers;
• M-anticholinergics.

Sympathomimetics are almost never used in cardiology practice. Ephedrine and amphetamine are excreted in this group, which, in addition to stimulating the production of norepinephrine, have a strong effect on the brain, so these drugs were replaced by safer analogues.

There are also drugs that have a dual effect - both on myocardial function and on PSS (cardiac conduction system) - cardiac glycosides. These substances increase strength and decrease the speed of myocardial activity, but treatment with their help requires caution: glycosides in the wrong dosage are heart poison.

Grouping by another criterion - application depending on the nature of the disease - releases drugs for the elimination of heart block and drugs used for extrasystole, tachyarrhythmia, tachycardia.

The first group includes such substances:

• M-anticholinergics;
• beta adrenomimetics;
• sympathomimetics.

All of them directedly affect the nerves, including the system of the tubules of the heart to conduct an electrical impulse, so this classification is not considered the main one.

The main groups of drugs and their mechanism of action

Extrasystole is a phenomenon in which additional impulses appear in the heart rhythm. It can also occur in healthy people, but a violation on an ongoing basis is the first sign of arrhythmia. Tachyarrhythmia is a pathology that is characterized by an excessive rate of atrial contraction.

Based on these two states, as the most common, a classification according to Vogen-Williams is developed. Four classes are distinguished in it: membrane stabilizers, beta-blockers, substances that block potassium channels and substances that block calcium channels.

Membrane stabilizing sodium channel blockers

The principle of action of these antiarrhythmics is based on stopping the process of movement of Na ions into the cell: the conductivity of the channels along which charged elements move, decreases under the influence of blockers. This prevents abnormal impulses to excite the myocardium.

The passage of an electrical signal through the heart tissue - the action potential - consists of several phases. The effect on the different stages of this process defines three classes of blockers.

1. The first type is class 1A antiarrhythmics. They are prescribed to prevent and eliminate attacks of atrial fibrillation (if this is provoked by excessive excitability of the nerve responsible for the innervation of the heart muscle - vagus), with ventricular forms of tachycardia. Novocainamide, which belongs to this group, is a seizure blocker in patients with congenital Wolf-Parkinson-White anomaly.
2. Class 1B drugs. They are prescribed to neutralize the ventricular types of extrasystoles, atrial fibrillation, paroxysmal tachycardia and cardiac dysfunctions caused by glycoside poisoning.
3. The third type is class 1C products. They are necessary for rhythm equalization in pathologies associated with bundles of James and Kent - abnormal formations between one of the atria and ventricles, with atrial fibrillation. In modern medicine, they are rarely used, since their proarrhythmic effects can cause new forms of cardiac pathologies or aggravate existing ones.

Beta blockers

These drugs for cardiac arrhythmias directedly affect the nerve structures responsible for blood circulation, reducing the degree of negative effect on the muscle tissue of the heart. In stressful situations or in the presence of certain heart diseases, the concentration of neurotransmitters in excess of the norm is fixed in the blood plasma. These are norepinephrine, dopamine and adrenaline. Because of their effects, the myocardium unstably conducts nerve impulses. This forms heterogeneous arrhythmias.

Beta-blockers are responsible for a decrease in the activity of cardiac beta-adrenergic receptors during their excessive stimulation caused by catecholamines (mainly adrenaline). The drugs protect the myocardium from electrical stress.

Medications are used to reduce or completely neutralize the risk of death from myocardial infarction, to prevent sinus tachycardia, supraventricular arrhythmia, they are effective in atrial fibrillation.If ventricular arrhythmia is caused by excessive exposure to neurotransmitters, then it is also eliminated by beta-blockers.

Potassium Channel Blockers

The principle of operation of these funds is based on blocking potassium channels, which slows down the movement of an electrical impulse along nerve cells in the myocardium. Another advantage is inhibition of alpha-adrenergic receptors, which also reduces the load on the bulk of cardiomyocytes, as well as blocking beta-adrenergic receptors like beta-blockers.

Medications are prescribed in the treatment of supraventricular, atrial, ventricular arrhythmias, to eliminate rhythmic pathologies in Wolf-Parkinson-White disease.

Calcium antagonists

Also known as calcium channel blockers, which explains the mechanism of action. The bottom line is to stop the movement of Ca ions, which reduces the automatic excitation of the sinoatrial node and prevents the occurrence of abnormal shock.

The drug prevents the appearance of additional heart attacks, which is effective for the treatment of conditions such as atrial flutter and atrial fibrillation, supraventricular forms of tachycardia.

Sometimes the last generation is released, the fifth class is sodium adenosine triphosphate, magnesium sulfate, and potassium preparations. The first drug reduces the conduction of atrioventricular congestion of nerves, which makes it effective for WPW syndrome, supraventricular tachycardia. The second type of antiarrhythmics reduces the activity of cardiomyocytes, normalizes the conductivity of the cell membrane. The third reduces the rate of electrical reactions in the heart muscle.

List of herbal products

Almost all of the above groups of drugs are herbal remedies. But natural origin does not negate the wide range of side effects common to all antiarrhythmics.

The dosage determined by the doctor and timely therapy reduce the risk of negative effects. It is important to familiarize yourself with contraindications when taking antiarrhythmic drugs.

1. Quinidine, related to sodium blockers, is often prescribed as a dragee. The following negative manifestations are distinguished: dyspeptic disorders, dizziness. Rarely in practice has severe tachycardia, leading to instant death of the patient.
2. Novocainamide belongs to the same class. Indications for use are similar. During use, the appearance of nerve disorders, vomiting, unwanted variations in the blood test. The drug should be administered slowly to prevent severe cardiac hypotension. Therapy should not be long, otherwise the appearance of fever, arthritis, serositis (inflammation of the pleura, peritoneum or other serous membrane) is likely.
3. Lidocaine is an IB class drug. It is administered intravenously. Illiterate use is fraught with convulsions, impaired vision, speech, mental disorders. Cases of the development of an allergy to the drug are recorded.
4. IC preparations are rarely used, but among them the most widely used is Rhythmorm (sometimes - Propanorm, Propafenone). Side effects include dyspeptic disorders, a bitter-metallic taste on the tongue, and nervous disorders.
5. A common beta-blocker - Anaprilin - helps to reduce the frequency of heart attacks, reduce peripheral blood flow. It is not prescribed to patients with any form of diabetes mellitus, bronchial asthma.
6. Cordarone - a means to block potassium channels. Prolonged use of the drug can cause pulmonary fibrosis, impaired vision, memory, and insomnia. The drug accumulates in the body for a long time, so it is important to enter it slowly. The effect will be noticeable only after two or three weeks from the start of therapy.
7. The representative of the calcium antagonist group is Verapamil. A negative effect on the body manifests itself as sinus bradycardia, a significant decrease in blood pressure.

If we are talking about exclusively herbal remedies, then it is worth mentioning sedatives - Persen, Novo-Passit, Valerian tincture. However, one should not expect a powerful positive effect from them.

There are other means, less popular, but used, especially by foreign cardiologists. The distribution of drugs into groups is presented in the table below.

Domestic and foreign manufacturers

Antiarrhythmic drugs are widely marketed. There are more than 100 manufacturers.

Domestic funds benefit at the expense of price, but a high concentration of active substances is suitable only for short-term therapy. Many foreign drugs are better perceived by the body, but more expensive than Russian counterparts.

Below is a table of imported drugs.

Among the Russian drugs, the following can be distinguished:

• Kinidin Durules (Quinidine) - AstraZeneca Pharmaceuticals LLC;
• Lidocaine - Borisov plant of medical preparations of OJSC (OJSC "BZMP");
• Lidocaine - Veropharm OJSC;
• Novocainamide injection 10% - Moskhimpharmpreparat them. N.A. Semashko;
• Amiodarone, Lidocaine - Organika AO;
• Kordaron (Amiodaron) - Representation of Sanofi-aventis Group Joint-Stock Company;
• Amiodaron - North Star CJSC;
• Rhythmiodaron (Amiodarone) - Pharmstandard OJSC.

Understanding the principle of operation of antiarrhythmic drugs can effectively correct heart failure. It is important that the remedy clearly matches the indications that arise from the cause. For example, short-term tachycardia and extrasystole amid stress, overfatigue is eliminated with sedatives or a change in lifestyle. Pathological phenomena affecting the cardiovascular system require an integrated approach.

With arrhythmia, self-medication should not be performed.

Correctly choose and prescribe the necessary drug can only a cardiologist. But for the patient it is important to understand how this or that medicine works to prevent possible side effects and relapses.