What are antiarrhythmic drugs? Top list of antiarrhythmic drugs - we select an effective medicine for arrhythmia Antiarrhythmic drugs.

Almost all patients of the cardiologist faced one way or another with various kinds of arrhythmias. Currently, the pharmacological industry offers a wide variety of antiarrhythmic drugs. Their classification and characteristics will be considered in this article.

Ways of exposure

To eliminate ectopic heart rhythm disturbances, antiarrhythmic drugs are prescribed. The mechanism of action of such drugs is aimed at the electrophysiological properties of working myocardial cells:

Classification of antiarrhythmic drugs

All medicines in this group are divided into four classes. Additionally, the first class is divided into three more subclasses. This classification is based on the degree to which drugs affect the ability of heart cells to generate and conduct electrical signals. Different classes of antiarrhythmic drugs have their own routes of action, so their effectiveness will differ for different types of arrhythmia.

The first class includes blockers of fast sodium channels. Subclass IA includes drugs such as Quinidine, Disopyramide, Novocainamide, Gilurithmal. Subclass IB includes Pyromecaine, Tocainide, Difenin, Lidocaine, Aprindine, Trimecaine, Mexiletine. The IC subclass is formed by such agents as Etmozin, Ritmonorm (Propafenone), Allapinin, Etacizin, Flecainide, Indecainide, Bonnecor, Lorcainide.

The second class is made up of beta-blockers (Metoprolol, Nadolol, Alprenolol, Kordanum, Propranolol, Acebutalol, Pindolol, Trazikor, Esmolol).

The third class includes potassium channel blockers: Bretilium tosylate, Amiodarone, Sotalol.

The fourth class includes blockers of slow calcium channels (for example, "Verapamil").

The list of antiarrhythmic drugs does not end there. Potassium chloride, sodium adenosine triphosphate, and magnesium sulfate are also isolated.

First class drugs

Blockers of fast sodium channels stop the flow of sodium into the cells, which slows down the passage of the excitation wave through the myocardium. Thanks to this, the conditions for rapid circulation of pathological signals in the heart are stopped, and the arrhythmia is eliminated. Let us consider in more detail the groups of antiarrhythmic drugs belonging to the first class.

Class IA drugs

Such antiarrhythmic drugs are prescribed for and supraventricular), as well as to restore sinus rhythm in case of atrial fibrillation (atrial fibrillation). In addition, they are used to prevent recurrent attacks.

"Novocainamide" and "Quinidine" are effective antiarrhythmic drugs for tachycardia. Let's talk about them in more detail.

"quinidine"

This medicine is used in case of paroxysmal and paroxysmal atrial fibrillation to restore sinus rhythm. Most often, the medicine is prescribed in the form of tablets.

Poisoning with antiarrhythmic drugs is rare, but when taking Quinidine, side effects are possible in the form of indigestion (vomiting, loose stools) and headache. In addition, the use of this medication can cause a decrease in the level of platelets in the blood, a slowdown in intracardiac conduction, and a decrease in myocardial contractility. The most dangerous side effect is the development of a special form of ventricular tachycardia, which can cause sudden death of the patient. That is why Quinidine therapy should be carried out only with the control of the electrocardiogram and under the supervision of a specialist.

The drug is contraindicated in intraventricular and atrioventricular blockade, intoxication with cardiac glycosides, thrombocytopenia, arterial hypotension, heart failure, pregnancy.

"Novocainamide"

This medication has the same indications for use as Quinidine. Quite often it is prescribed for the purpose of stopping paroxysms of atrial fibrillation. With an intravenous injection of Novocainamide, a sharp decrease in blood pressure is possible, as a result of which it is necessary to administer the solution as slowly as possible.

Among the side effects are nausea, vomiting, changes in the composition of the blood, disorders of the nervous system in the form of dizziness, headache, in rare cases, confusion. If you use the drug constantly, a lupus-like syndrome (serositis, arthritis, fever), a microbial infection in the oral cavity, accompanied by slow healing of wounds and ulcers and bleeding gums, may develop. In addition, Novocainamide can provoke an allergic reaction, in this case, the first sign will be the appearance of muscle weakness when the drug is administered.

It is forbidden to use the medication for atrioventricular blockade, severe forms of renal and heart failure, arterial hypotension and cardiogenic shock.

Class IB

Such drugs have little effect on the sinus node, atrioventricular junction and atria, and therefore are ineffective in the case of supraventricular arrhythmias. These antiarrhythmic drugs are prescribed for extrasystole, paroxysmal tachycardia, that is, for the treatment of ventricular arrhythmias. They are also used to treat arrhythmias, which are provoked by an overdose of cardiac glycosides.

The list of antiarrhythmic drugs of this class is quite extensive, but the most commonly used remedy is Lidocaine. As a rule, it is administered intravenously in case of severe ventricular arrhythmias, including myocardial infarction.

"Lidocaine" can disrupt the functioning of the nervous system, which is manifested by dizziness, convulsions, problems with speech and vision, and a disorder of consciousness. If you enter the drug in a large dose, it is possible to slow down the heart rate, reduce the contractility of the heart. In addition, allergic reactions are likely in the form of Quincke's edema, urticaria, skin itching.

"Lidocaine" is contraindicated in atrioventricular blockade, syndrome The drug is not prescribed in case of severe supraventricular arrhythmia, since the risk of atrial fibrillation increases.

IC class

Drugs belonging to this class lengthen intracardiac conduction, especially in the His-Purkinje system. They have pronounced arrhythmogenic properties, so they are currently used to a limited extent.

The list of antiarrhythmic drugs of this class was given above, but of these, only Propafenone (Ritmonorm) is mainly used. It is prescribed for supraventricular and ventricular arrhythmias, including with ERW syndrome. Since there is a risk of an arrhythmogenic effect, the medication should be used under the supervision of a doctor.

In addition to arrhythmias, this drug can cause progression of heart failure and deterioration of cardiac contractility. Side effects include a metallic taste in the mouth, nausea and vomiting. Such negative effects as visual disturbances, changes in the blood test, dizziness, insomnia, and depression are not excluded.

Beta blockers

When the tone of the sympathetic nervous system rises, for example, in case of stress, hypertension, vegetative disorder, ischemia, many catecholamines appear in the blood, including adrenaline. These substances act on myocardial beta-adrenergic receptors, which leads to electrical cardiac instability and the appearance of arrhythmias.

Beta-blockers prevent excessive stimulation of receptors and thus protect the myocardium. In addition, they reduce the excitability of the cells of the conduction system, which leads to a slowdown in the heart rate.

Medicines of this class are used in the treatment of flutter and atrial fibrillation, for the prevention and relief of supraventricular arrhythmias. In addition, they help to overcome sinus tachycardia.

Ineffective considered antiarrhythmic drugs for atrial fibrillation, except in cases where the pathology is caused precisely by an excess of catecholamine in the blood.

For the treatment of rhythm disturbances, Metoprolol and Anaprilin are often used. These drugs have side effects in the form of a slowing of the pulse, a decrease in myocardial contractility, and the occurrence of atrioventricular blockade. These medications can provoke cold extremities and deterioration of peripheral blood flow. In addition, drugs affect the nervous system, causing drowsiness, dizziness, depression, and memory impairment. They also change the conductivity in the nerves and muscles, which is manifested by fatigue and weakness.

Beta-blockers are prohibited for use in cardiogenic shock, pulmonary edema, insulin-dependent diabetes mellitus, bronchial asthma. Also contraindications are atrioventricular blockade of the second degree, sinus bradycardia.

Potassium channel blockers

The list of antiarrhythmic drugs in this group includes agents that slow down electrical processes in the cells of the heart and thereby block potassium channels. The most famous drug of this class is Amiodarone (Cordarone). Among other things, it acts on M-cholinergic and adrenergic receptors.

"Kordaron" is used for the treatment and prevention of ventricular, atrial and supraventricular arrhythmias, heart rhythm disturbances against the background of ERW syndrome. The drug is also prescribed to prevent life-threatening ventricular arrhythmias in patients with acute myocardial infarction. In addition, it is used to reduce the heart rate in persistent atrial fibrillation.

If you use the product for a long time, an interstitial change in skin color (appearance of a purple hue) may develop. In some cases, there are headaches, sleep disturbances, memory, vision. Reception of "Amiodarone" can cause the development of sinus bradycardia, constipation, nausea and vomiting.

Do not prescribe medication for initial bradycardia, prolongation of the Q-T interval, impaired intracardiac conduction, thyroid diseases, arterial hypotension, pregnancy, bronchial asthma.

Blockers of slow calcium channels

These drugs block the slow flow of calcium, thereby suppressing ectopic foci in the atria and reducing the automatism of the sinus node. The list of antiarrhythmic drugs in this group includes "Verapamil", which is prescribed for the prevention and relief of paroxysms of supraventricular tachycardia, for the treatment of supraventricular extrasystole. "Verapamil" is ineffective in case of ventricular arrhythmias.

Side effects include atrioventricular block, sinus bradycardia, and in some cases, a decrease in cardiac contractility.

cardiac glycosides

The classification of antiarrhythmic drugs will not be complete without mentioning these drugs. These include drugs such as Celanide, Korglikon, Digitoxin, Digoxin, etc. They are used to restore sinus rhythm, stop supraventricular tachycardia, and reduce the frequency of ventricular contractions in case of atrial fibrillation. When using cardiac glycosides, you need to monitor your condition. Signs are manifested by abdominal pain, nausea and vomiting, headaches, visual and sleep disturbances, nosebleeds.

It is forbidden to use these antiarrhythmic drugs for bradycardia, SVC syndrome, intracardiac blockades. They are not prescribed in the case of paroxysmal ventricular tachycardia.

Combination of antiarrhythmic drugs

With ectopic rhythms, some combinations of medications are used in clinical practice. So, "Quinidin" can be used in conjunction with cardiac glycosides for the treatment of persistent extrasystole. With beta-blockers, Quinidine can be prescribed to stop ventricular arrhythmias that are not amenable to other treatment. The combined use of beta-blockers and cardiac glycosides gives a good effect in ventricular and supraventricular extrasystoles, and also helps to prevent recurrence of tachyarrhythmias and ectopic tachycardias.

antiarrhythmic drugs (syn. antiarrhythmic drugs) - a group of drugs used to prevent and relieve cardiac arrhythmias.

P. s. according to the classification proposed in 1971-1972. Singh and Williams (V. N. Singh, V. E. M. Williams), are divided into 4 groups.

The first group includes drugs that have membrane-stabilizing properties: quinidine (see), novocainamide (see), disopyramide (syn. Rimodan), aymalin (see), ethmozine, see), mexitil, lidocaine, trimecaine (see) and difenin (see). In the concentrations required to detect antiarrhythmic action, they have a comparable effect on the electrophysiological characteristics of myocardial fibers. The drugs of this group have the ability to reduce the maximum rate of depolarization of myocardial cells due to the dysfunction of the so-called. fast sodium channels in the cell membrane. In therapeutic concentrations, this action is manifested by an increase in the threshold of excitability, inhibition of conduction, and an increase in the effective refractory period. In this case, there is no significant change in the resting potential of the cell membrane and the duration of the action potential, but the suppression of spontaneous diastolic depolarization of the cells of the conduction system of the heart is constantly recorded.

Therapeutic effect P. s. of this group is observed in arrhythmias (see Arrhythmias of the heart), arising as a result of the circulation of an excitation wave in a closed CIRCLE as a result of a change in the effective refractory period, and in arrhythmias, which are based on the mechanism of increasing automatism or reducing the excitability threshold, as a result of suppression of spontaneous diastolic depolarization.

The second group P. with. includes propranolol (see) and other β-blockers that have anti-arrhythmic action hl. arr. due to the blockade of sympathetic effects on the heart, carried out through β-adrenergic receptors. Blockers of β-adrenergic receptors, inhibiting the activity of adenylate cyclase of cell membranes, inhibit the formation of cyclic AMP, which is an intracellular transmitter of the effects of catecholamines, which are involved under certain conditions in the genesis of arrhythmias. Electrophysiologically, the action of drugs of this group in therapeutic doses is characterized by inhibition of the fourth phase of depolarization. However, the significance of this phenomenon in the mechanism of their antiarrhythmic action is still unclear. β-blockers increase the duration of the action potential of myocardial cells.

The third group P. s. represented by amiodarone (cordarone) and ornid (see). Amiodarone moderately inhibits sympathetic innervation, but does not interact with β-adrenergic receptors. In experimental work, it was shown that amiodarone does not have a membrane-stabilizing effect and has extremely weakly expressed properties inherent in the first group of P. s.

Ornid renders antiarrhythmic action, the mechanism to-rogo remains not clear. It is believed that it is due to the inhibitory effect of this drug on the release of norepinephrine from the endings of the sympathetic nerves.

In the fourth group P. s. include inhibitors of transmembrane transport of calcium ions. The most active is verapamil (see). Using electrophysiological research methods, it has been established that it causes an extension of the 1st and 2nd phases of the action potential due to blockade of the calcium channels of the cell membrane, which is accompanied by an antiarrhythmic effect. This is evidenced by experimental data on the role of disturbances in the slow calcium current through the membranes of myocardial cells in the genesis of certain types of arrhythmias. With such arrhythmias, the ectopic focus appears as a result of the activation of the ionic mechanism of the "slow response" type, which is normally characteristic of the cells of the sinus and atrioventricular nodes. It is assumed that this mechanism is involved in the occurrence of arrhythmias associated both with the circulation of the excitation wave and with increased automatism.

Thus, an antiarrhythmic effect can be obtained as a result of the effect of antiarrhythmic drugs on various electrophysiological properties of myocardial cells.

On efficiency at different forms of arrhythmias among P. of page. it is possible to allocate mainly effective at supraventricular disturbances of a rhythm (eg, verapamil), hl. arr. with ventricular arrhythmias (lidocaine, trimecaine), with supraventricular and ventricular arrhythmias (aymalin, quinidine, novocainamide, disopyramide, etc.).

When determining indications for P.'s appointment with. the form of the arrhythmia, the nature of the underlying disease, the conditions that contributed to the onset of the arrhythmia, as well as the nature and characteristics of the action of the drugs, should be taken into account.

Verapamil prescribed for supraventricular extrasystoles and supraventricular paroxysmal tachycardia resulting from the circulation of the excitation wave in the sinoatrial region, atria, atrioventricular node. However, in patients with premature ventricular excitation syndrome, with Krom during a paroxysm of tachycardia (especially atrial fibrillation), impulses in the anterograde direction are carried out along the Kent bundle, verapamil can, by improving conductivity, worsen the course of arrhythmia.

Application lidocaine and trime-caine is limited to parenteral administration of these drugs in order to suppress ventricular arrhythmias in acute myocardial infarction, cardiac surgery, intoxication with cardiac glycosides. In the case of arrhythmias associated with hypokalemia, these drugs are ineffective. Lidocaine sometimes also has a stopping effect in supraventricular tachycardias, in which additional pathways are included in the circulation of the excitation wave.

Difenin appoint chief. arr. with ventricular arrhythmias arising from intoxication with cardiac glycosides and hypokalemia. Patients with severe heart failure and impaired atrioventricular conduction are usually prescribed only lidocaine (in small doses) or difenin; the majority of P. of page. they are contraindicated.

In heart failure without conduction disturbances, in addition to these drugs, etmosin and amiodarone can also be prescribed.

In the syndrome of bradytachycardia (sick sinus syndrome), the use of disopyramide, quinidine, verapamil or P-adrenoreceptor blockers can lead to an increase in the duration of asystole, and therefore they should be prescribed with caution.

Special care is required by P.'s choice of page. for patients with additional ways of conducting excitation in the anterograde direction along the Kent bundle. This is due to the fact that individual drugs from among P. s. stop attacks of arrhythmia, but be able to prevent their occurrence. Besides, some P. with. may contribute to tachycardia. So, in patients with Wolff-Parkinson-White syndrome and wide ventricular complexes during paroxysm, the use of glycosides or verapamil can lead to an improvement in conduction along the Kent bundle, and in case of flutter or atrial fibrillation, cause ventricular fibrillation. In such cases, it is recommended to prescribe lidocaine, novocainamide, aymalin or amiodarone to stop the attack.

With nodal atrioventricular paroxysmal tachycardia, it is most advisable to use verapamil, obzidan, amiodarone, as well as cardiac glycosides, which have the ability to slow down the rate of excitation in the atrioventricular node. With such arrhythmias, novocainamide and quinidine are ineffective, since they do not affect the conductivity in this node. However, novocainamide and quinidine can be used to prevent seizures, since they suppress extrasystole, which, under certain conditions, is a triggering factor in the occurrence of paroxysmal tachycardia.

For the relief of atrial fibrillation, intravenous administration of novocainamide, aimaline, amiodarone is recommended; with satisfactory tolerability of an attack inside, quinidine, disopyramide or novocainamide are prescribed in appropriate doses. Verapamil and cardiac glycosides are used only to slow down the ventricular rate.

In patients with ventricular tachycardia, lidocaine is the most effective for interrupting an attack, which, if necessary, can be prescribed at the maximum therapeutic dose (until moderately severe symptoms from CP appear). In the absence of the effect of lidocaine, other drugs are used (taking into account contraindications).

Tactics of treatment P. with. is determined by the severity of the course of the disease and the prognostic value of the existing cardiac arrhythmias. There is no doubt that in order to prevent the constant use of drugs with frequently recurring (several times a week) paroxysms, frequent extrasystole, accompanied by severe hemodynamic disturbances and poor health, causing disability or life-threatening. Patients with rare bouts of tachycardia (tachyarrhythmia) or with relatively frequent attacks that occur without a sharp violation of the general condition, which are easily stopped, can be recommended to receive P. s. just to stop them.

The doctor's tactics in the treatment of patients with asymptomatic extrasystoles or with minor wedge manifestations is determined by the prognostic value of extrasystoles. Prospective observations have shown that in practically healthy individuals, supraventricular or ventricular extrasystoles are not life-threatening, so the accidental detection of an asymptomatic cardiac arrhythmias (without heart disease) in them should not serve as an indication for the use of P. s. However, with hron, coronary heart disease, ventricular extrasystoles significantly worsen the prognosis for life, and therefore patients should be prescribed drugs that have antianginal and antiarrhythmic effects.

There are data testifying to the possibility of development in some cases of the arrhythmogenic effect of all active P. s. In this regard, with Wolff-Parkinson-White syndrome, ventricular tachycardia and ventricular fibrillation, individual selection of P. is necessary. with the help of acute drug tests (intravenous or oral administration of P. s. starting with small doses, which are brought to the maximum allowable) under careful electrocardiographic control at rest and during exercise or against the background of an artificially imposed heart rhythm, which allows timely detection of the arrhythmogenic effect of P . With. and provide emergency assistance as needed.

In the absence of effect from the appointment of any one drug, P.'s combinations are used. from various groups. The most rational is the simultaneous appointment of beta-blockers with quinidine or cardiac glycosides. However, it is not recommended to combine P. with. having the same mechanism of action or having the opposite effect on the electrophysiological properties of the myocardium and the conduction system of the heart.

Clinical and pharmacological characteristics of the main P. s. shown in the table.

The name of the drug (Russian and Latin) and the main synonyms (typed in italics are published in separate articles)

Therapeutic doses and methods of application

Indications for use in arrhythmias

to relieve seizures

for the prevention of arrhythmias

Absolute and relative contraindications

Forms of release and storage

Causes moderate hypotension, slightly increases coronary blood flow, has a moderate adrenolytic effect. Reduces myocardial excitability, lengthens the refractory period, slows down atrioventricular and intraventricular conduction, inhibits the automatism of the sinus node.

The antiarrhythmic effect develops in the first minutes after intravenous administration. Duration of action 6-8 hours.

Intravenously 2-3 ml of 2.5% solution for 7-10 minutes. or inside 0.05 - 0.1 g

Inside, 0.05 - 0.1 g 3-4 times a day

Hypotension, nausea, weakness, feeling of heat

Conduction disorders, heart failure, hypotension

Tablets of 0.05 g; 2.5% solution in ampoules of 2 ml.

Amiodarone (Amiodarone); synonym: Cordarone, Cordarone, Trangorex, etc.

Causes moderate expansion of peripheral and coronary vessels. Reduces pre- and afterload on the heart, as well as its work. It has a moderately pronounced sympatholytic effect and leads to a nek-rum decrease in heart rate and blood pressure. Lengthens the effective refractory period of the atria and ventricles, slows down the conduction of the atrioventricular node.

The antiarrhythmic effect when administered intravenously develops within a few minutes and reaches a maximum after 15 minutes. and continues approx. 30 minutes. When taken orally, the duration of action is several days.

Over ventricular and ventricular arrhythmias

Intravenously at the rate of 5 mg/kg

Inside according to the following scheme: the first week, 1-2 tablets 3 times a day, the second week, 1-2 tablets 2 times a day, then 1-2 tablets in courses lasting 5 days with a two-day break between courses

Decreased appetite, nausea, constipation, decreased thyroid function, allergic reactions.

Overdose may cause bradycardia.

Severe bradycardia, sick sinus syndrome, II-III degree heart block, hypotension, bronchial asthma, thyroid dysfunction, pregnancy

Tablets of 0.2 g; ampoules containing 0.15 g of the drug.

Expands coronary and peripheral arteries. When administered intravenously, it briefly worsens myocardial contractility, lowers blood pressure. Reduces the spontaneous activity of the sinus node, slows down atrioventricular conduction, suppresses ectopic activity in the atria and the atrioventricular node.

The antiarrhythmic effect after intravenous administration reaches a maximum after 3-5 minutes. and lasts 4-7 hours; when taken orally, it develops after 1 hour and reaches a maximum after 3-5 hours.

Intravenously 4 ml (sometimes 6-8 ml) 0.25% solution at a rate of 0.5-1 ml / min or orally 0.04-0.12 g (sometimes up to 0.16 g)

Inside, 0.04 g (in severe cases, 0.08 g) 3-4 times a day

Headache, pruritus, constipation, hypotension, atrioventricular conduction disturbances

Heart failure, atrioventricular conduction disorders, sick sinus syndrome, hypotension, therapy with ß-blockers; Wolff-Parkinson-White syndrome with atrial fibrillation

Tablets of 0.64 g; 0.25% solution in ampoules of 2 ml.

Storage: sp. B.; in a place protected from light

Disopyramide (Disopyramid); synonym: rhythmodan, Rythmodan

It has moderate hypotensive and anticholinergic effects. Inhibits myocardial contractility. Reduces excitability and slows down the conduction of the myocardium, lengthens the effective refractory period.

The antiarrhythmic effect develops in 30-40 minutes. after ingestion. Duration approx. 4-6 hours.

Supraventricular and ventricular arrhythmias

Inside, 0.1-0.2 g 3-4 times a day

Hypotension, tachycardia, nausea, vomiting, dry mouth, urinary retention, constipation, visual disturbances

Heart failure, blockade of atrioventricular conduction stage II - III, sick sinus syndrome, hypotension, individual intolerance

Tablets 0.1 and 0.2 g.

Has anticonvulsant action. With rapid intravenous administration, it causes a decrease in peripheral resistance, a decrease in cardiac output and hypotension. Increases coronary blood flow. Reduces atrioventricular blockade caused by glycosides; exhibits antiarrhythmic activity in conditions of hypokalemia. Shortens the duration of the effective refractory period and increases the speed of excitation.

The duration of the antiarrhythmic effect after oral administration is 6-12 hours; the maximum effect develops on the 3rd-5th day of taking the drug

Inside during or after meals, 0.1 g 3-4 times a day (for slow "saturation") or 0.2 g 5 times a day (for fast "satiation")

Dizziness, ataxia, nystagmus, dysarthria, loss of appetite, hepatitis, anemia, skin rash, etc.

Severe heart failure, liver damage, hypotension

Tablets of 0.117 g of a mixture of diphenylhydantoin and sodium bicarbonate in a ratio of 85: 15 (each tablet corresponds to 0.1 g of difenin).

Storage: sp. B; in a well-closed container, protected from light

Lidocaine (Lidocaine Hydrochloride); Syn.: Xylocaine, Xycaine, Lidocaini Hydrochloridum, Lignocain, Xylocard, Xylocitin, etc.

It has a local anesthetic effect. Affects the conduction of impulses in the affected ventricular myocardium and in additional pathways, does not affect the electrophysiological characteristics of the atrial myocardium.

The antiarrhythmic effect develops in the first minutes from the start of intravenous administration.

Intravenous * bolus 4-6ml 2% solution for 3-5 minutes. or 10 ml of 2% solution for 5-10 minutes.

Repeat if necessary

Intravenously, at first 4-6 ml of 2% solution, then drip in 5% glucose solution at a rate of 2-3 ml / min; after 10-15 min. from the beginning of the drip injection, 2-3 ml of a 2% solution is repeatedly injected. Intramuscularly, 4-6 ml of 10% solution every 3 hours

Dizziness, numbness of the tongue, lips, drowsiness, weakness.

With rapid intravenous administration, hypotension and collapse may develop.

Intolerance to drugs such as novocaine, severe heart failure, hypokalemia

2 and 10% solution in 2 ml ampoules.

Storage: sp. B; in a place protected from light

Mexitil (Mexitil); syn. mexiletine

It has a moderate local anesthetic and anticonvulsant effect. With initially disturbed conduction, it can increase its severity. When administered intravenously, it reduces cardiac output and peripheral resistance.

The antiarrhythmic effect develops when administered intravenously in the first minutes after administration, when taken orally - after 1 to 2 hours. Duration approx. 6-8 hours.

0.075-0.25 g for 5-15 minutes. Inside 0.3-0.4 g; if necessary up to 0.6 g

Inside, 0.2-0.4 g 3-4 times a day

Dizziness, nystagmus, speech difficulty, nausea, vomiting, tremor, hypotension

Hypotension, severe heart failure, weakness of the sinus node, severe violations of intraventricular conduction

Storage: sp. B; in a place protected from light

It has a local anesthetic effect, inhibits excitability, conductivity and, to a lesser extent, myocardial contractility. When administered intravenously, it causes a hypotensive effect. Suppresses ectopic activity in the atria and ventricles.

When taken orally, the maximum antiarrhythmic effect develops through

supraventricular and ventricular arrhythmias

Intravenously 5-10 ml of 10% solution at a rate of 1-2 ml for 2 minutes.

Intravenous drip at the rate of 2-3 ml / min. Intramuscularly, 5 - 10 ml of 10% solution (up to 20 - 30 ml per day). Inside, 0.25 - 0.5 g every 4 hours (daily do-

Nausea, vomiting, diarrhea, hallucinations, lupus-night syndrome.

With an overdose and increased individual sensitivity, cardiac depression is possible.

Violation of atrioventricular and intraventricular conduction, heart failure, increased individual sensitivity to novocaine

Tablets of 0.25 g; 10% solution in hermetically sealed vials of 10 ml and ampoules of ■ 5 ml.

Storage: sp. B; in a place protected from light

1-2 hours. Duration approx. 3-4 hours.

It has a sympatholytic effect. It inhibits the release of norepinephrine from the endings of sympathetic nerves, reducing the effect of sympathetic innervation on effector organs. Reduces excitability and contractility of the myocardium, slows down conduction, lengthens the refractory period.

Antiarrhythmic effect with parenteral administration develops in 20-40 minutes. Duration approx. 8 o'clock

Intravenously at the rate of 0.1 ml of 5% solution per 1 kg of body weight (mass) for 10-15 minutes.

for no more than 4 g)

Intramuscularly or subcutaneously, 0.5-1 ml of 5% solution 2-3 times a day

Hypotension, weakness, dyspeptic disorders, temporary visual impairment

Hypotension, cerebrovascular accident

Ampoules of 1 ml 5% solution.

Storage: sp. B; in a place protected from light

Blocks β-adrenergic receptors. It reduces the strength of heart contractions, slows down the pulse, lengthens the systole period, reduces systolic volume and cardiac output, reduces the volumetric rate of coronary blood flow, and reduces myocardial oxygen demand. Reduces blood pressure, increases total peripheral resistance and tone of bronchial muscles. Suppresses glycogenolysis and lipolysis. Reduces excitability of the myocardium, suppresses automatism, eliminates the ability of catecholamines to shorten the refractory period.

The antiarrhythmic effect develops maximally after 5 minutes. after intravenous administration and 1-2 hours after ingestion. Duration of action at intravenous administration apprx. 2-4 hours, when taken orally approx. 3-6 hours.

Supraventricular and ventricular arrhythmias

Intravenously, 1-2 ml of 0.1% solution every 2 minutes. up to a total dose of 5-10 ml. Inside 0.08-0.16 g

Inside for 15-30 minutes. before meals starting from a dose of 0.02 g

3-4 times a day; gradually increase the daily dose to 0.2-0.3 g in

Hypotension, nausea, vomiting, weakness, cold hands, feet, intermittent claudication, bronchospasm, allergic reactions

Bronchial asthma, heart failure, severe bradycardia, sick sinus syndrome, hypotension, intermittent claudication, hypoglycemia, atrioventricular block, peptic ulcer, hypothyroidism

Tablets of 0.01 and 0.04 g; ampoules of 1 and 5 ml of 0.1% solution.

Storage: sp. B; in a place protected from light

Quinidine sulfate (Chinidini sulfas); syn.: Chinidinum sulfuricum, Quinidi-ni Sulfas, etc.

It has a moderate anticholinergic and negative inotropic effect. It has a local anesthetic and vasodilating effect, slows down the sinoatrial and intraventricular conduction. Increases the threshold of chemical and electrical atrial and ventricular fibrillation, lengthens the refractory period of the heart.

The antiarrhythmic effect develops 2-3 hours after ingestion. Duration of action 4-6 hours.

Inside, 0.2-0.4 g 4-6 times a day

Nausea, diarrhea, abdominal pain, hearing loss, vision impairment, thrombocytopenia, anemia, agranulocytosis, allergic reactions.

Overdose may cause cardiac depression.

Heart failure, atrioventricular block III stage, hypotension, saturation with cardiac glycosides, increased individual sensitivity

Tablets of 0.1 g.

Storage: sp. B; in a place protected from light

Possesses a nek-swarm koronarodilating, antispasmodic and anticholinergic activity, almost does not influence inotropic function of a myocardium. Slows down conduction, prolongs effective refractory period and reduces cardiac excitability

Intravenously 4-6 ml of 2.5% solution for 5-7 minutes.

Inside, 0.2 g 3-4 times a day

Noise in the head, dizziness, numbness of the tip of the tongue, lips, nausea, abdominal pain, pruritus

Conduction disorders, liver and kidney dysfunction, hypotension

Coated tablets of 0.1 g; 2 ml ampoules of 2.5% solution.

Storage: sp. B; in a place protected from light

Bibliography: Mazur N. A. The current state and prospects for studying cardiac arrhythmias, Cardiology, t. 18, No. 4, p. 5, 1978; it e, Questions of terminology, classification of disturbances of a cordial rhythm and tactics of their treatment, Bull. All-Union. cardiol. scientific center of the USSR Academy of Medical Sciences, vol. 3, no. 2, p. 8, 1980; Sumarokov A. V. and Mikhailov A. A. Heart arrhythmias, M., 1976; H and z about in E. I. and Bogolyubov V. M. Heart rhythm disturbances, M., 1972; Krone R. J. a. K 1 e i g e g R. E. Prevention and treatment of supraventricular arrhythmias, Heart a. Lung, v. 6, p. 79, 1977; Opie L. H. Drugs and the heart, Lancet, v. 1, p. 861, 1980; Rosen M. R. a. Hoffman B. F. Mechanisms of action of antiarrhythmic drugs, Circulat. Res., v. 32, p. 1, 1973; Singh B. N. a. Vaughan Williams E. M. Effect of altering potassium concentration on the action of lidocaine and diphenylthydantoin on rabbit atrial and ventricular muscle, ibid., v. 29, p. 286, 1971; are they A fourth class of anti-dysrhythmic action? Effect of verapamil on ouabain toxicity, on atrial and ventricular intracellular potentials, and on other features of cardiac function, Cardiovasc. Res., v. 6. p. 109, 1972; Singh B. N.. Collett J. T. a. Chew Ch. Y. C. New perspectives in pharmacological therapy of cardiac arrhythmias, Progr. cardiovasc. Dis., v. 22, p. 243, 1980; Winkle R. A., G I a n t z S. A. a. Harrison D. C. Pharmacologic therapy of ventricular arrhythmias, Amer. J. Cardiol., v. 36, p. 629.1975.

Antiarrhythmic drugs: classification and description

Antiarrhythmic drugs are a group of drugs prescribed to normalize the heart rhythm. Such compounds of chemical elements have their own classification. These drugs are intended for the treatment of tachyarrhythmia and other manifestations of this disease, and also prevent the development of heart rhythm disturbances. The use of antiarrhythmic drugs does not increase the overall life expectancy of the patient, but only allows you to control some of the symptoms of the disease.

Varieties

The drugs are necessary for patients who have been diagnosed with a failure of the contractile features of the main organ for pathological reasons. This condition threatens human life and worsens its quality. An antiarrhythmic drug is able to have a positive effect on the entire body of the patient and stabilize the activity of all systems and organs. It is necessary to drink such tablets only as prescribed by the doctor and under the control of diagnostic measures, such as an ECG.

There is such a concept in medicine as “innervation of the heart”, which means that the activity of the organ is constantly controlled by the endocrine and nervous systems. The organ is supplied with nerve fibers that regulate its work, if there is an increase or decrease in the frequency of contractions of this department, then the cause is often sought precisely in disorders of the nervous or endocrine system.

Antiarrhythmic drugs are necessary to stabilize sinus rhythm, this is the most important part of therapy. Often, the patient is treated in a hospital setting, administering drugs of this effect intravenously. When concomitant pathologies of the cardiovascular system have not been identified, it is possible to improve a person's condition on an outpatient basis by taking pills.

The classification of antiarrhythmic drugs is based on the ability of such drugs to influence the production and normal conduction of electrical impulses in cardiomyocytes. The division is carried out by classes, of which there are only four. Each class has a specific path of influence. The effectiveness of drugs for different types of heart rhythm disturbances will be different.

Type of drugs and description:

1. Beta blockers. This group of drugs is able to influence the innervation of the heart muscle, controlling it. This remedy reduces the mortality of patients from acute coronary insufficiency, and can also prevent the recurrence of tachyarrhythmia. Medicines: "Metaprolol", "Propranolol", "Bisoprolol".
2. Membrane stabilizing sodium channel blockers. The indication for the use of this drug is a violation of the functionality of the myocardium. Medications: "Lidocaine", "Quinidine", "Flecaidine".
3. calcium antagonists. The drug of this group has an effect that reduces the tone of the sympathetic nervous system, and also reduces the oxygen demand of the myocardium. Medications: "Diltiazem", "Verapamil".
4. Calcium channel blockers. The principle of influence on the body of these drugs is based on a decrease in the excitability of the heart, a reduction in the automatism of the myocardium. In addition, the drug slows down the conduction of nerve impulses in the departments of the body. Medicines: "Ibutilide", "Amiodarone", and also "Sotalol".
5. Additional funds, the mechanism of action of which is different. Neurotropic drugs, tranquilizers, cardiac glycosides and others.

The classification of antiarrhythmic drugs is different, but physicians more often subdivide such drugs according to Vaughan-Williams. What kind of medicine is needed for a particular patient depends on the cause that caused the heart rhythm disorder.

It is impossible to choose an antirhythmic correctly without the help of a doctor. The properties of drugs are known only to specialists, each of the representatives of such drugs can harm a person if you drink it without a doctor's prescription.

Characteristic 1 class

The mechanism of action of such drugs is the ability of certain chemicals to block sodium channels, as well as reduce the speed of the electrical impulse in the myocardial region. Arrhythmia is often characterized by a violation of the movement of the electrical signal, it spreads in a circle, which provokes the heart to contract more often, in the absence of control over this process of the main sinus. Drugs blocking sodium channels help to normalize this mechanism.

The first class of drugs is distinguished by a large group of antiarrhythmic drugs, which is divided into subclasses. All these branches have almost the same effect on the heart, reducing the rate of its contractions within a minute, but each individual representative of such drugs has its own characteristics that only specialists know for sure.

Description of class 1A products

In addition to sodium, such medicines can block potassium channels. A good antiarrhythmic effect complements a strongly pronounced analgesic effect. These drugs are prescribed for supraventricular and ventricular extrasystole, atrial fibrillation, tachycardia.

The main representative of such drugs is Quinidine, it is most often used in treatment. It is convenient to take the remedy, it is available in the form of tablets, but there are side effects and contraindications to therapy with this medication. Due to the fact that the toxicity of such drugs is high, as well as a large number of negative reactions of the body during treatment, these representatives of class 1A are used only to stop an attack. Further use is carried out with the help of drugs of other varieties.

Medicines 1B class

The use of drugs in this group is justified when the need arises not to inhibit (inhibit) potassium channels, but to activate them. They are prescribed mainly for violations in the ventricles of the heart, namely, extrasystole, tachycardia or paroxysm. Usually the drug is administered intravenously, but such drugs already exist in the form of tablets.

The effect of these drugs on the human body makes it possible to use them even in the case of myocardial infarction. Side effects from taking the medication are minor and usually manifest as disorders of the nervous system, inhibiting its function. Complications of a cardiological nature are practically not observed.

Of the entire list of such drugs, the most famous is Lidocaine, which is used frequently and can serve as an anesthetic in other areas of medicine. It is noteworthy that if you drink a medicine, then its effect will be very weak, almost imperceptible. Intravenous infusions have the opposite effect, manifesting pronounced antiarrhythmic effects on the human body. Lidocaine is known to cause allergic reactions, so you should be careful when using this remedy.

Class 1C drugs

Representatives of this subgroup are the most powerful drugs that block calcium and sodium ions. The action of such medicines extends to all areas of the transmission of an electrical impulse, starting from the area of ​​​​the sinus node. Used in treatment usually as oral tablets. Means of this group have a wide range of effects on the body, are highly effective in tachycardia of various nature, atrial fibrillation and other heart pathologies. Therapy can be carried out both to quickly stop an attack, and as a permanent treatment for ventricular or supraventricular arrhythmias. If any damage to the heart of an organic nature is detected, the medicines of this group are contraindicated.

It should be noted that all class 1 drugs have limitations for the treatment of people with severe heart failure, with scars on the organ, its other changes and tissue pathologies. Statistics show that among patients who have such disorders, treatment with such drugs has increased the number of deaths.

The latest generation of antiarrhythmic drugs, which are called beta-blockers, are seriously different in all respects from representatives of the class 1 drug group, they are much safer and more effective.

Description of 2 class funds

The chemicals that make up these drugs slow down the heart rate in various diseases of this organ. The indication for admission is usually atrial fibrillation, some types of tachycardia, as well as ventricular fibrillation. In addition, these drugs help to avoid the harmful effects of emotional disorders on the course of the disease. Catecholamines, namely adrenaline, being produced in increased quantities, can adversely affect the heart rhythm, causing an increased contraction of the organ. With the help of class 2 medications, it is possible to avoid negative manifestations in such situations.

Also, funds are prescribed to people who are in a state after myocardial infarction, this improves the functioning of the cardiovascular system, and also reduces the risk of death. It is important to consider that the drugs in this group have their own contraindications and side effects.

Long-term use of such medications can adversely affect the sexual function of men, as well as cause disturbances in the bronchopulmonary system and increase the amount of sugar in the blood. Among other things, beta-blockers are completely contraindicated in bradycardia, low blood pressure and any form of heart failure. Doctors fix a significant depression of the central nervous system, if the patient drinks such pills for a long time, depressive disorders may occur, memory deteriorates and the musculoskeletal system weakens.

Medicines 3rd class

The drugs of this group differ in that they prevent the entry of charged potassium atoms into the cell. Such drugs slow down the heart rate slightly, unlike representatives of class 1 drugs, but they are able to stop atrial fibrillation, which lasts for a long time, weeks and months. In such a situation, other means are usually powerless, so doctors resort to prescribing class 3 drugs.

Among the side effects, there are no such in relation to the heart rhythm, and as for the negative impact on other parts of the body, doctors are able to control it during the treatment period. When prescribing such medicines, the peculiarity of their combination with drugs of various groups is necessarily taken into account.

You can not take these drugs simultaneously with cardiac drugs, antirhythmics of other effects, diuretics, antibacterial drugs from the category of macrolides, as well as anti-allergy drugs. With the appearance of cardiac disorders, as a result of improper combination of drugs, sudden death syndrome may develop.

Mechanism of action 4 classes

These drugs reduce the amount of charged calcium atoms entering the cells. This affects many parts of the cardiovascular system, as well as the automatic function of the sinus node. At the same time, by expanding the lumen of the vessels, such drugs can lower blood pressure and reduce the number of organ beats per minute. In addition, this effect prevents the formation of blood clots in the arteries.

Means of class 4 help to correct antiarrhythmic disorders in myocardial infarction, angina pectoris, arterial hypertension. Doctors with caution prescribe such medications if the patient is diagnosed with atrial fibrillation, accompanied by SVC syndrome. Side effects include bradycardia, a drop in blood pressure much lower than normal, and circulatory failure. These antiarrhythmic drugs allow you to take them about twice a day, as they have a prolonged effect on the body.

Other antirhythmics

The Vaughan-Williams classification does not include other antiarrhythmic drugs. Doctors combined such funds into a class 5 group. Such medications can reduce the rate of heart contractions, as well as have a beneficial effect on the entire cardiovascular system. The mechanism of influence on the human body for all these drugs is different.

Representatives of funds of the 5th group:

Cardiac glycosides have an effect based on the properties of cardiac poisons of natural origin. If the dosage of the drug is chosen correctly, then the therapeutic effect of taking it will be positive, the activity of the entire cardiovascular system will be restored. Similar medications are prescribed for attacks of tachycardia, manifestations of heart failure, flutter and atrial fibrillation by slowing down the conduction of the nodes. It is often used as a replacement for beta-blockers when their reception is not possible.

Preparations cardiac glycosides:

Exceeding the permissible doses can adversely affect the activity of the heart, cause intoxication of a specific type.

Salts of sodium, potassium and magnesium can compensate for the lack of important minerals in the body. In addition, these drugs change the level of electrolytes, help to remove an excess of other ions, especially calcium. Often, such drugs are prescribed instead of antiarrhythmic drugs of groups 1 and 3.

These medicines are used in medicine to prevent certain disorders of the functioning of the cardiovascular system.

"Adenazine" is often used as an ambulance for attacks of sudden paroxysm. Usually the drug is administered intravenously and several times in a row, due to the short period of exposure. It is prescribed to maintain the course of therapy and for prevention in the treatment of any pathologies of the heart.

"Ephedrine" is the complete opposite of beta-blocker drugs. This tool increases the susceptibility of receptors, and also has a stimulating effect on the central nervous system, blood vessels and heart. Long-term use of this medication is not recommended by doctors, more often the medicine is used as an emergency.

Herbal antirhythmic drugs

Arrhythmia requires a serious approach to therapy, usually doctors prescribe drugs of chemical origin, but not the last place is occupied by herbal remedies. Such medicines have practically no contraindications and side effects, therefore they are considered safer. However, you can not start taking such drugs on your own, you need to coordinate this with your doctor.

These medicines contain only natural herbal ingredients. Treatment with only such means has a weak therapeutic effect, but can serve as an auxiliary method to enhance the properties of other drugs. The calming effect also allows you to reduce the heart rate, as well as help a person survive an arrhythmia attack without panic.

Of the adverse reactions of the body to these drugs, allergic manifestations that occur on plant components can be distinguished. Contraindications to admission are bradycardia and low blood pressure. Before using infusions and decoctions of any herbs, it is necessary to consult a doctor, because even such harmless representatives of nature can have a negative effect on the body.

Antiarrhythmic drugs today are quite diverse, but choosing the right drug is not easy. Medicine does not stand still and the latest generation of medicines are already being developed, which allow not only to regulate the heart rate, but also to prevent the development of serious conditions caused by pathology. Only after passing all the diagnostic measures, you can accurately determine the cause of the disease and prescribe treatment. Drinking such pills on your own is dangerous, it can worsen your health and lead to sad consequences.

ANTI-ARITHMIC MEDICINES

Used for violations of the rhythm of heart contractions - arrhythmias. The causes of arrhythmias are pathological changes in the myocardium.

Types of arrhythmias (determined by ECG data).

1. Depending on the location of the pathological focus:

a) supraventricular (supraventricular);

b) ventricular.

2. By the nature of rhythm disturbance:

a) tachyarrhythmias (extrosystole, paroxysmal tachycardia, flutter, atrial fibrillation and ventricular fibrillation);

b) bradyarrhythmias (various blockades and weakness of the sinus node).

Mechanisms of arrhythmias

1. Violation of the formation of impulses, that is, the occurrence of pathological foci of excitation.

2. Violation of the conduction of impulses as a result of the block.

MECHANISM OF EXCITATION AND CONTRACTION IN THE MYOCARDIA

Under the influence of the action potential of the cells of the sinus node, the permeability of the cell membranes changes. Ca** and Na* enter inside the cell, K* comes out. The contractile mechanism is activated, contraction occurs, then Ca** ions are removed from the cell, relaxation occurs.

Excitation (action potential)

Maple membrane

Inlet Ca** and Na* Outlet K*

cell contraction

Exit Ca**

Cell relaxation

The main causes of rhythm disturbances are electrolyte disturbances, that is, a deficiency of K * and Mg **, an excess of Na * and Ca ** that occur in the myocardium under the influence of hypoxia, inflammatory processes, toxic or autoimmune damage, increased tone of SS innervation, excess thyroid hormones glands.

P\arrhythmic drugs belong to different chemical and pharmacological groups. Only quinidine, novocainamide, ethmozine and aymaline are used only as antiarrhythmics.

CLASSIFICATION OF ANTI-ARITHMIC DRUGS

I. For the treatment of tachyarrhythmias.

1) Membrane stabilizing drugs (sodium channel blockers). Divided into 3 gr.

2) b-adrenolytics (b-blockers).

3) Drugs that slow down repolarization (potassium channel blockers).

4) Antagonists of Ca ions ** (calcium channel blockers).

5) Drugs of other groups (cardiac glycosides, potassium preparations, magnesium preparations, hawthorn n-ka, adenosine).

II. For the treatment of bradyarrhythmias.

M-cholinolytics (in / in 0.1% solution of atropine).

B-agonists (izadrin sublingually or intravenously, orciprenaline (alupent) inside).

The mechanism of action of all a / arrhythmic cf-in is based on the effect on cell membranes and the transport of Na *, K *, Ca **, Cl * ions through them. As a result, electrophysiological processes in the myocardium change.

ANTI-ARRHYTHMIC DRUGS FOR THE TREATMENT OF TACHYARHYTHMIAS

Membrane-stabilizing drugs - disrupt the transport of Na* and K* ions through the membranes of the heart fibers. The properties of the fibers change, the excitability, conductivity and automatism of the fibers of the conduction system of the heart decrease. Subdivided into 3 groups:

1gr.- Meh-m: block the entry of Na* ions through the fast sodium channels of the cell membrane.

Application: extrasystoles, ventricular tachyarrhythmias, supraventricular (paroxysmal tachycardia, atrial fibrillation).

Side effects: the appearance of signs of heart failure, a decrease in blood pressure, in large doses - AV block, mx / blocking effect (dry mouth, blurred vision); when ingested, nausea, vomiting.

Quinidine is an alkaloid from cinchona bark. Dextrorotatory isomer of quinine.

Side effects: ototoxic, hemolysis, hepatitis. It is impossible for arrhythmias associated with intoxication with cardiac glycosides.

PV tab 0.1 and 0.2.

extended forms:

Quinidine-durules

Kinileptin

Procainamide (Novocainamide) - similar in structure and properties to novocaine (has a local anesthetic effect), according to indications and f-log effects - with quinidine (less M-anticholinergic effect), in addition, convulsions, psychosis, a condition similar to systemic red lupus. It is impossible for arrhythmias associated with intoxication with cardiac glycosides.

PV tab 0.25; 10% solution, 5 ml.

Aymalin (Rauwolfia snake alkaloid) - parenterally.

Pulsnorma (aymalin + phenobarbital) - antiarrhythmic and hypotensive, dragee.

Disopyramide (ritmilen, ritmodan, norpeys) has a negative inotropic effect and a peripheral anticholinergic effect.

2 gr.-Meh-m: promote the release of K* ions from myocardial cells, accelerate the process of repolarization of cell membranes, shorten the action potential and refractory period. Suppress the automatism of ectopic foci of excitation in the ventricles. Do not adversely affect conductivity.

Lidocaine (Xycaine) and Trimecaine are local anesthetics.

Application: drugs of choice for ventricular arrhythmias, myocardial infarction.

Side effects: dizziness, convulsions, nausea, vomiting, lowering blood pressure. Enter in / m and / in.

Mexiletine (Ritalmex) and tocainide, an analog of lidocaine with a longer duration of action, are effective when taken orally.

VW capsules and solutions for intravenous administration.

Phenytoin (difenin) is an antiepileptic drug. Similar to lidocaine in antiarrhythmic properties. It is effective only for arrhythmias caused by intoxication with cardiac glycosides and heart operations. PV tablets.

3 gr.- Meh-m: (cm 1 gr) - block the entrance of Na *, but less than 1 gr inhibit the conductivity and contractility of the myocardium.

Ethmozine (moriciazine) and etacizine are well absorbed from the gastrointestinal tract. Assign inside and parenterally.

Application: ventricular arrhythmias.

Side effects: nausea, dizziness, blurred vision, own arrhythmogenic effect. VW tab and 2.5% solutions for injections.

Beta-adrenolytics (see the lecture "Beta-adrenolytics")

Propranolol (anaprilin, obzidan) is a non-selective beta-blocker that blocks the effect of adrenergic innervation on the heart, as well as circulating adrenaline. At the same time, the activity of the sinus node and ectopic foci is suppressed. Reduces automatism, excitability and conduction of the myocardium. Stabilizes the content of potassium ions in the heart muscle. Effective in supraventricular and ventricular tachyarrhythmias, including those associated with cardiac glycosides.

Side effect: associated with the blockade of beta2-adrenergic receptors of other organs (bronchospasm, cold extremities due to deterioration of peripheral circulation).

Atenolol (tenolol) is a beta1-adrenolytic (cardioselective). It does not cause side effects on beta2-adrenergic receptors, it is better tolerated. It is used for the same indications as propranolol.

Atenolol analogues: metoprolol, talinolol, bisoprolol, betaxolol, acebutolol, nebivolol, etc.

Drugs that slow down repolarization

Amiodarone (cordarone) is a highly effective antiarrhythmic drug. Mech-m action: increases the duration of the action potential, due to the blockade of potassium channels. Slows down the conduction of the impulse through the conduction system, but does not affect the contractility of the myocardium. Expands coronary vessels. Application: supraventricular and ventricular arrhythmias. Side effects: pigment deposition in the cornea of ​​the eye, headache, changes in the lungs, thyroid dysfunction (TC contains iodide ion).

Contraindications: violation of atrioventricular conduction, bradycardia, pregnancy, lactation. PV tab 0.2

Sotalol (Sotalex, Sotohexal) is a non-selective beta-blocker. Reduces blood pressure - even normal. Lasts about 25 hours. But doctors recommend taking 2 times a day.

Application: arrhythmias, angina pectoris. FV

Bretylium (ornid) is a sympatholytic, most effective in ventricular arrhythmias. VW 5% solution for intravenous and intramuscular administration.

Calcium channel blockers (Ca ion antagonists**)

Meh-m action and f-log effects: block calcium channels in cell membranes, mainly in the smooth muscles of blood vessels and the heart. Antiarrhythmic action is associated with a decrease in excitability, conductivity and automatism of the fibers of the sinus and atrioventricular nodes. They have a negative inotropic effect (weaken, lengthen systole). As a result, they reduce blood pressure, have an antiplatelet effect and reduce blood viscosity. They have antianginal action.

Verapamil (lekoptin, isoptin, veronorm) and diltiazem (cardil) are the drugs of choice for supraventricular tachyarrhythmias.

Side effect:

in high doses, they reduce myocardial contractility, causing AV block;

constipation, headache, fatigue, swelling in the legs.

Drugs of other groups

cardiac glycosides. With arrhythmias, only digitalis preparations are prescribed in tablets:

Purple: cordigite, digitoxin;

Woolly: Digoxin, Medilazide, Celanide

Potassium preparations cause an increase in the rhythm of heart contractions. Reduce excitability, conductivity and contractility of the myocardium. In small doses, they dilate the coronary vessels of the heart, in large doses, they cause a spasm of the coronary vessels.

Well absorbed from the gastrointestinal tract, excreted through the kidneys.

In case of an overdose, the phenomenon of paresthesia is observed: itching on the skin, burning, "crawling crawling" is accompanied by a tick on the face. Kidney function is impaired. Cardiac arrest, as a result of spasm of the coronary vessels. Application: hypokalemia when taking soluretics, digitalis intoxication, arrhythmias.

Potassium chloride - after eating, because it strongly irritates the gastrointestinal mucosa. PV tab 0.5

Potassium - normin, calinor, kalipoz - tab in the shell, before meals, without chewing.

Magnesium preparations reduce the heart rate, the excitability of ventricular cardiomycetes.

Magnesium sulfate 20% solution is used to stop ventricular arrhythmias, poisoning with cardiac glycosides.

Magnesium chloride, magnesium orotate (magnerot), magnesium aspartate and magnesium gluconate are used to prevent and treat hypomagnesemia.

Magne B6, magnesium-plus, magnil - combined preparations of magnesium.

Combined preparations of potassium and magnesium. Application: cardiac arrhythmias caused by hypokalemia and hypomagnesemia.

Asparkam and panangin are analogues, contain potassium and magnesium asparaginates. The action develops gradually. Asparkam acts more sharply and less long. FV tab, dragee, solution for injections.

Polarizing mixture - composition: 5% glucose solution -500 ml; 6 units of insulin; 1.5 potassium chloride; 2.5 magnesium sulfate. In/in drip.

Hawthorn tincture - hawthorn preparations increase the contraction of the heart muscle and at the same time reduce its excitability. Increase blood circulation in the coronary vessels of the heart and in the vessels of the brain. Analogues: novocainamide, quinidine, ethmozine.

Drugs for the treatment of bradyarrhythmias, bradycardias and conduction disorders (see classification).

Arrhythmic conditions of pathological etiology require specialized medical treatment. All antiarrhythmic drugs are prescribed by a cardiologist - self-medication is strictly prohibited.

Antiarrhythmic drugs

They are prescribed to patients after passing a full diagnostic examination, making a final diagnosis of the pathological nature of arrhythmic problems. Conditions can threaten and interfere with the full life of the patient.

Medicines have a positive effect on the body - the normalization of the rhythm of contractions allows you to stabilize the work of the circulatory department, with the timely delivery of oxygen and nutrients to the tissues of the internal organs. Medications ensure the full functioning of all internal systems.

Antiarrhythmic drugs require monitoring by medical professionals - their effects are constantly monitored by an electrocardiogram procedure, at least once every 20 days (the course of therapy is usually quite long).

Upon admission to the cardiology department, the patient is prescribed intravenous or oral medication. If the desired positive effect is not recorded, then the patient is recommended to conduct an electrical type of cardioversion.

In the absence of chronic pathologies of the cardiovascular department, the patient may be shown outpatient treatment - with periodic consultations of a cardiologist. If attacks of arrhythmia are rare and short-lived, then the patient is transferred to dynamic observation.

The principle of action of these medicines

Antiarrhythmic drugs have a positive effect:

• to lower the level of excitability of the organ;
• decrease in the sensitivity of the heart muscle in relation to electrical impulses, with the prevention of the formation of fibrillation;
• reduction of manifestations of accelerated heartbeat;
• suppression of additional impulses;
• shortening the interval of the contractile impulse;
• an increase in the duration of diastole.

Classification

The division of drugs is carried out according to four main classes, depending on the ability of the drug to conduct electrical impulses. There are several forms of arrhythmic deviations, in accordance with which the necessary pharmacological substances are selected.

The main drugs include:

• sodium channel blockers;
• beta blockers;
• potassium antagonists;
• calcium antagonists.

Other forms of medications are represented by cardiac glycosides, tranquilizers, sedatives and neurotropic drugs. They are characterized by a combined effect on the innervation and performance of the heart muscle.

Table: division of antiarrhythmics into classes

Representatives of major groups and their action

The antiarrhythmic effect depends on the subgroup of drugs. Among them are:

1A class

These drugs are necessary for two types of extrasystoles - supraventricular and ventricular, to restore sinus rhythm in atrial fibrillation, in order to prevent its recurrence. Commonly used agents include Quinidine and Novocainamide.

Quinidine- is administered in tablet form. The negative impact on the body when used is represented by:

• dyspeptic disorders - nausea, vomiting, diarrhea;
• sudden attacks of headache.

When taking a pharmacological agent, there is a decrease in the number of platelets in the blood stream, a decrease in the level of contractility of the heart muscle, and a slowdown in the functionality of the conduction system in the heart.

The most dangerous side effects include the formation of a separate ventricular tachycardia, with the possible development of a fatal outcome. The therapy is carried out under the constant supervision of medical personnel and ECG readings.

Quinidine is prohibited for use:

• with blockades of atrioventricular and intraventricular character;
• thrombocytopenia;
• poisoning - with uncontrolled intake of cardiac glycosides;
• insufficient functionality of the heart muscle;
• hypotension - with minimal blood pressure;
• during the childbearing period.

Novocainamide- recommended for use according to the same indicators as the previous drug. It is prescribed to suppress attacks of atrial fibrillation. At the time of intravenous administration of the substance, a sudden drop in blood pressure may occur - therefore, the solution must be used with the utmost care.

The negative effect of the drug is represented by:

• nausea with the transition to vomiting;
• changes in the blood formula;
• collapse;
• violations of the functionality of the nervous system - sudden attacks of headaches, periodic dizziness, changes in the clarity of consciousness.

Continuous uncontrolled use may cause arthritis, serositis or feverish conditions. There is a possibility of the formation of infectious processes in the oral cavity, with the formation of bleeding and delayed healing of ulcers and small wounds.

A pharmacological substance can provoke allergic reactions - the initial symptomatic manifestations of the problem are muscle weakness, which manifests itself when using the drug. The drug is prohibited for use:

• with atrioventricular blockade;
• insufficient functionality of the heart muscle or kidneys;
• in cardiogenic shock conditions;
• hypotension - with extremely low blood pressure.

1B class

These drugs are not effective in detecting supraventricular arrhythmia in a patient - the active ingredients do not have the necessary effect on the sinus node, atrium and atrioventricular junction.

The drugs are used to treat ventricular-type arrhythmic abnormalities - extrasystoles, paroxysmal tachycardias, to treat problems associated with overdose or uncontrolled use of cardiac glycosides.

The main representative of this subgroup is Lidocaine. It is prescribed for severe forms of ventricular disturbances in the rhythm of organ contraction, in the acute phase of myocardial infarction. The drug can cause negative reactions of the body:

• convulsive conditions;
• periodic dizziness;
• decreased visual acuity;
• problems with intelligible speech;
• impaired clarity of consciousness;
• rashes on the skin;
• hives;
• angioedema;
• persistent itching.

Incorrectly calculated dosages can provoke a decrease in the level of contractility of the heart muscle, a slowdown in the speed of contractions, rhythm disturbances - up to arrhythmic deviations.

The pharmacological substance is not recommended for use in atrioventricular blockade, the pathology of the weakening of the sinus node. Severe forms of supraventricular arrhythmic conditions are contraindications - there is a high risk of atrial fibrillation.

1C class

These pharmacological substances are able to lengthen the time of intracardiac conduction. Against the background of pronounced arrhythmogenic efficacy, the drugs received a restriction on their use. The main representative of the subgroup is Ritmonorm.

The drug is necessary to suppress the negative symptomatic manifestations of ventricular or supraventricular arrhythmias. When taken, there is a high risk of the formation of an arrhythmogenic effect, therapy is carried out under the constant supervision of a medical worker.

In addition to arrhythmic pathologies, the drug can provoke disturbances in the contractility of the heart muscle, further development of insufficient functionality of the organ. Pathological abnormalities can manifest themselves:

• nausea;
• vomiting;
• metallic taste in the mouth;
• dizziness;
• decreased visual acuity;
• depressive states;
• night sleep disturbances;
• changes in blood tests.

Grade 2

A large amount of adrenaline produced is recorded with an increase in the functionality of the sympathetic nervous section - in stressful situations, vegetative abnormalities, arterial hypertension, ischemic damage to the heart muscle.

The hormone stimulates the activity of beta-adrenergic receptors in the muscle tissues of the heart - the result is unstable heart function and the formation of arrhythmic abnormalities. The main mechanism of action of these drugs includes the suppression of increased receptor activity. The heart muscle is protected.

In addition to the above positive effects, drugs reduce the automatism and the level of excitability of the cellular elements that make up the conductive department. Under their direct influence, the speed of contractions of the heart muscle slows down. By reducing atrioventricular conduction, medications reduce the frequency of organ contractions at the time of atrial fibrillation.

Drugs are prescribed for the treatment of atrial fibrillation and fibrillation, for the suppression and prophylactic effect of supraventricular arrhythmic conditions. Help with sinus tachycardia.

Ventricular forms of the pathological process are less susceptible to the influence of beta-blockers - the exception is a disease that is directly related to an excess of hormones in the bloodstream. As the main means of treatment, the use of Anaprilin and Metoprolol is recommended.

The negative impact of the above medications includes a decrease in the level of contractility of muscle tissues, a slowdown in the rate of heart contractions, and the formation of atrioventricular blockade. Pharmacological substances can significantly disrupt the functionality of the circulatory department, cause a decrease in the temperature of the lower and upper extremities.

The use of Propranolol can provoke a deterioration in bronchial conduction - pathology is dangerous for patients suffering from bronchial asthma. Beta-blockers can worsen the course of diabetes mellitus - when used, there is an increase in glucose in the bloodstream.

Medications can affect the nervous system - provoke spontaneous dizziness, disturbed night sleep, memory loss, cause depressive states. Drugs disrupt the conduction of the neuromuscular department, manifesting itself in the form of increased fatigue, weakness, and a decrease in muscle tone.

In some cases, rashes on the skin, persistent itching and focal alopecia may appear. Erectile dysfunction may occur in males, and thrombocytopenia and agranulocidosis can be observed in blood counts.

Drugs with sudden cancellation cause pathological conditions:

• anginal attacks;
• violations of the rhythm of the heart muscle at the level of the ventricles;
• increase in blood pressure;
• acceleration of the pulse;
• decrease in the level of exercise tolerance.

Cancellation of drugs is carried out in stages, over two weeks. Beta-blockers are prohibited for use with insufficient functionality of the organ, swelling of the lung tissues, cardiogenic shock conditions, and severe cases of chronic heart failure. Also, their appointment is not recommended for diabetes mellitus, sinus type of bradycardia, a drop in systolic pressure below 100 units and bronchial asthma.

3rd grade

The drugs are potassium channel antagonists, with a slowdown in electrical processes in the cellular structures of the heart muscle. Amiodarone is a commonly prescribed drug in this subgroup.

The drug gradually accumulates in tissue structures and is released at the same rate. The maximum efficiency is recorded three weeks after the start of administration. After discontinuation of the drug, the antiarrhythmic effect may persist for the next five days.

• with supraventricular and ventricular arrhythmia;
• atrial fibrillation;
• rhythm disturbances against the background of Wolff-Parkinson-White pathology;
• to prevent ventricular arrhythmias in acute myocardial infarction;
• with persistent atrial fibrillation - to suppress the frequency of contractions of the heart muscle.

Prolonged and uncontrolled medication can provoke:

• interstitial fibrosis of lung tissue;
• fear of sunlight;
• changes in the shade of the skin - with staining in purple;
• violation of the functionality of the thyroid gland - at the time of therapy, mandatory monitoring of thyroid hormone levels is carried out;
• decreased visual acuity;
• night sleep disturbances;
• lowering the level of memory;
• ataxia;
• paresthesia;
• sinus bradycardia;
• slowing down the process of intracardiac conduction;
• nausea;
• vomiting;
• constipation;
• arrhythmogenic effects - are recorded in 5% of patients who were prescribed medication.

The drug is toxic to the fetus. Use is prohibited:

• initial type of bradycardia;
• pathology of intracardiac conduction;
• hypotension;
• bronchial asthma;
• diseases with damage to the thyroid gland;
• period of bearing a baby.

If there is a need to combine a drug with cardiac glycosides, then their dosage is halved.

4th grade

Drugs can block the passage of calcium ions, lowering the automatic reactions of the sinus node and suppressing pathological foci in the atrial zone. The main frequently recommended drug in this subgroup is Veropamil.

The drug has a positive effect in the treatment and prophylactic effect on attacks of supraventicular tachycardia, extrasystole. The drug is necessary to suppress the frequency of ventricular contractions, at the time of atrial flutter and fibrillation.

The drug does not have the necessary effect on the ventricular forms of rhythmic contractions of the organ. Negative reactions of the body to taking the medication are expressed:

• sinus bradycardia;
• atrioventricular block;
• a sharp drop in blood pressure;
• decrease in the ability of the heart muscle to contract.

The ban on the use of the drug are:

• severe forms of insufficient organ efficiency;
• cardiogenic shock conditions;
• atrioventricular blocking;
• pathology of Wolff-Parkinson-White syndrome - the use can provoke an increase in the rate of contractions of the ventricles.

Other drugs with antiarrhythmic activity

The above subgroups of antiarrhythmic drugs do not include individual drugs with a similar positive effect on the heart muscle. Therapy can be carried out:

• cardiac glycosides - to reduce the rate of organ contraction;
• cholinolytics - drugs are prescribed to increase the heart rate with severe bradycardia;
• magnesium sulfate - for the appearance of a pathological process of the "feasting" type - non-standard ventricular tachycardia, which is formed under the influence of electrolyte metabolism disorders, a liquid protein diet and prolonged exposure to certain antiarrhythmic drugs.

Herbal products

Medicinal plants are quite effective means for the treatment of the pathological process. They are included in the composition of individual drugs and are officially recognized by medicine. Stabilization of heart rate indicators is performed:

1. Alcohol tincture of motherwort herb - the recommended dosage should not exceed 30 units, the drug is consumed up to three times a day. It is allowed to manufacture a home form of a drug, but it is freely sold in pharmacy chains and the long preparation process does not make logical sense.
2. Valerian - in free sale it can be found in the form of tinctures, tablets, herbal raw materials. The healing substance helps to suppress pain, restore the rhythm of contraction of the heart muscle, and has a calming effect. If long-term therapy is needed, then an antidepressant and a drug for problems with night sleep.
3. Persenom - refers to antiarrhythmic, antispasmodic, sedative substances that help normalize appetite and night sleep. An additional effect of the drug is to relieve psycho-emotional overstrain, suppress the constantly present irritability, and treat nervous fatigue.

What is prescribed most often for arrhythmias of various types

• Verapamil;
• Adenosine;
• Phenilin;
• Quinidin (Durules);
• Warfarin (Nycomed).

In addition to medications, treatment necessarily includes the use of multivitamin complexes.

Combination of antiarrhythmic drugs

Pathological rhythm in clinical practice allows you to combine individual drug subgroups. If we take the drug Quinidine as an example, then it is allowed to be used in conjunction with cardiac glycosides - to suppress the negative symptoms of constantly present extrasystole.

Together with beta-blockers, a drug substance is used to suppress ventricular forms of arrhythmic abnormalities that are not amenable to other types of therapy. The combined use of beta-blockers and cardiac glycosides makes it possible to achieve high rates of efficiency in tachyarrhythmias, focal tachycardias, and ventricular extrasystoles.

Side effects

Drugs of this subclass can provoke negative reactions of the body in response to their use:

• provoking arrhythmic abnormalities;
• spontaneous headaches;
• periodic dizziness;
• convulsive conditions;
• short-term loss of consciousness;
• tremor of the upper and lower extremities;
• constant sleepiness;
• lowering blood pressure;
• double vision of objects before the eyes;
• sudden stop of respiratory function;
• insufficient functionality of the kidneys;
• dyspeptic disorders;
• bronchospasm;
• problems with the process of urination;
• increased dryness of the mucous membranes of the oral cavity;
• allergic reactions;
• drug fever;
• leukopenia;
• thrombocytopenia.

31. Antiarrhythmic drugs. Mechanism of action. Indications for use.

Antiarrhythmic drugs - a group of drugs used for a variety of heart rhythm disorders, such as extrasystole, atrial fibrillation, paroxysmal tachycardia, ventricular fibrillation

1 class sodium channel blockers - quinidine, lidocaine, etazicin, etmozine

Slow down spontaneous depolarization, increase threshold potential

Indications: Ventricular arrhythmias, Prevention of attacks of atrial fibrillation caused by increased vagal tone

Grade 2 - beta-blockers - propranolol, atenolol, talinolol

Mechanism of action: reduce Ca and Na conductivity of membranes due to direct blockade of ion channels. Block B-AR of the conduction system of the heart

Application: stopping sinus tachycardia, extrasystoles

3rd grade - potassium channel blockers = amiodarone, sotalol, nibentan

Mechanism: block K channels and reduce repolarization., block Na and Ca channels, slow down the conduction of excitation in the atria, AV node, reduce the heart's need for oxygen.

Application: sinus tachycardia, ventricular tachycardia, CAD

4th grade -calcium channel blockers = verapamil, diltiazem

Mechanism actions: inhibit the entry of Ca ions, reduce the work of the heart, stabilize cell membranes.

Application tachycardia, estrosystole, atrial fibrillation, angina pectoris, arterial hypertension.

5th grade - bradycardic drugs = alinidine, falipamil.

They block the anion-selective (chlorine) channels of P-cells of the sinus node, therefore, they slow down spontaneous depolarization.

32. Classification of antiarrhythmic drugs.

I. Means that predominantly block ion channels of cardiomyocytes (the conduction system of the heart and contractile myocardium)

1. Sodium channel blocking agents (membrane stabilizing agents; group I)

Subgroup I A (quinidine and quinidine-like agents): Quinidine sulfate Disopyramide Novocainamide Aymalin

Subgroup IB: Lidocaine Difenin

Subgroup 1C:

Flecainide Propafenone Etmozine Etacizine

2. L-type calcium channel blockers (group IV) Verapamil Diltiazem

3. Means that block potassium channels (drugs that increase the duration of repolarization and, accordingly, the action potential; group III)

Amiodarone Ornid Sotalol

II. Drugs affecting mainly the receptors of the efferent innervation of the heart

Means that weaken adrenergic influences (group II)

beta-blockers

Anaprilin and others.

Drugs that enhance adrenergic effects

AT -Adrenergic agonists

Sympathomimetics Ephedrine hydrochloride

Means that weaken cholinergic influences

M-anticholinergics Atropine sulfate

III. Various drugs with antiarrhythmic activity Potassium and magnesium preparations Cardiac glycosides Adenosine