Beta blockers drugs names. The use of β-blockers in the treatment of arterial hypertension: a review of drugs

Before the first trials of β-blockers, no one expected that they would have an antihypertensive effect. However, it turned out that pronetalol (this drug has not found clinical use) reduces blood pressure in patients with angina pectoris and arterial hypertension (AH). Subsequently, the hypotensive effect was found in propranolol and other β-blockers.

Mechanism of action

The hypotensive effect of drugs in this group is determined precisely by their β-blocking action. Blockade of β-adrenergic receptors affects blood circulation through many mechanisms, including through a direct effect on the heart: a decrease in myocardial contractility and cardiac output. And on healthy people at restβ-blockers, as a rule, do not have a hypotensive effect, but reduce blood pressure in patients with hypertension, as well as during physical exertion or stress. In addition, against the background of blockade of β-adrenergic receptors, renin secretion decreases, and hence the formation of angiotensin II, a hormone that has multiple effects on hemodynamics and stimulates the formation of aldosterone, i.e., the activity of the renin-angiotensin-aldosterone system decreases.

Pharmacological properties

Beta-blockers differ in fat solubility, selectivity (selectivity) with respect to β 1 -adrenergic receptors, the presence of internal sympathomimetic activity (ICA, the ability of a β-blocker to partially excite β-adrenergic receptors that it suppresses, which reduces undesirable effects) and quinidine-like (membrane-stabilizing, local anesthetic) actions, but have the same hypotensive effect. Almost all β-blockers reduce renal blood flow fairly quickly, but kidney function is rarely affected even with long-term use.

Application

Beta-blockers are effective in hypertension of any severity. They differ significantly in pharmacokinetics, but the hypotensive effect of all these drugs is long enough that they can be taken twice a day. Beta-blockers are less effective in the elderly and dark-skinned, although there are exceptions. Usually these drugs do not cause salt and water retention, and therefore there is no need to prescribe diuretics to prevent the development of edema. However, diuretics and β-blockers enhance the hypotensive effect of each other.

Side effects

Beta-blockers should not be prescribed for bronchial asthma, sick sinus syndrome or atrioventricular conduction disorders, as well as during pregnancy and before childbirth.

They are not first-line drugs in the combination of hypertension with heart failure, as they reduce myocardial contractility and at the same time increase the total peripheral vascular resistance. Beta-blockers should also not be prescribed to patients with insulin-dependent diabetes mellitus.

Beta-blockers without ICA increase the concentration of triglycerides in plasma, and high-density lipoprotein cholesterol - reduce, but do not affect total cholesterol. Preparations with ICA almost do not change the lipid profile or even increase the level of high-density lipoprotein cholesterol. The long-term effects of these effects are not known.

After the abrupt cancellation of some β-blockers, a rebound syndrome occurs, manifested by tachycardia, heart rhythm disturbances, increased blood pressure, exacerbation of angina pectoris, the development of myocardial infarction, and sometimes even a sudden death. Thus, β-blockers should be discontinued only under close supervision, gradually reducing the dose over 10-14 days until completely cancelled.

Non-steroidal anti-inflammatory drugs, for example, indomethacin, can weaken the hypotensive effect of β-blockers.

A paradoxical increase in blood pressure in response to taking β-blockers is observed with hypoglycemia and pheochromocytoma, as well as after the abolition of clonidine or against the background of the administration of adrenaline.

I generation - non-selective β-blockers (blockers of β 1 - and β 2 -adrenergic receptors)

Non-selective β-blockers have a large number of side effects caused by the blockade of β 2 -adrenergic receptors: narrowing of the bronchi and increased cough, increased tone of the smooth muscles of the uterus, hypoglycemia, hypothermia of the extremities, etc.

Propranolol (Anaprilin, Obzidan®)

Kind of the standard against which other β-blockers are compared. It does not have an ICA and does not react with α-adrenergic receptors. Fat-soluble, therefore, it quickly penetrates the central nervous system, providing a calming effect. The duration of action is 6-8 hours. Rebound syndrome is characteristic. Possible individual hypersensitivity to the drug with a rapid and significant drop in blood pressure, so you should start taking propranolol with a small dose (5-10 mg) under medical supervision. The dosage regimen is individual, from 40 to 320 mg / day. in 2-3 doses for hypertension.

Pindolol (Whisken®)

It has BCA, moderate fat solubility, and also a weak membrane-stabilizing effect, which has no clinical significance. The dosage regimen is set individually from 5 to 15 mg / day. in two steps.

Timolol

A powerful β-adrenergic blocker that does not have an ICA and membrane stabilizing action. Dosage regimen - 10-40 mg / day in 2 divided doses. It is more widely used in ophthalmology for the treatment of glaucoma (in the form of eye drops), but even instillation of timolol into the conjunctival sac can cause a pronounced systemic effect - up to asthma attacks and decompensation of heart failure.

Nadolol (Korgard™)

Prolonged β-blocker (half-life - 20-24 hours), without quinidine-like action and ICA. Approximately equally blocks β 1 - and β 2 -adrenergic receptors. The dosage regimen is individual, from 40 to 320 mg per day once.

II generation - selective (cardioselective) β 1 -blockers

Selective β-blockers rarely cause complications, but it should be noted that in high doses, even they can partially block β 2 -adrenergic receptors, i.e. their cardioselectivity is relative.

Atenolol (Betacard®)

It used to be very popular. It is water-soluble, so it does not penetrate the blood-brain barrier well. Does not have an ICA. Cardioselectivity index - 1:35. Rebound syndrome is characteristic. The dosage regimen for hypertension is 25-200 mg / day. in 1-2 doses.

metoprolol

Metoprolol is a fat-soluble β-blocker, and therefore is used in the form of salts: tartrate and succinate, which improves its solubility and delivery rate to the vascular bed. The type of salt and production technology determine the duration of the therapeutic effect of metoprolol.

• Metoprolol tartrate is the standard form of metoprolol, the duration of the clinical effect of which is 12 hours. It is represented by the following trade names: Betaloc®, Corvitol®, Metocard®, Egilok®, etc. The dosage regimen for hypertension is 50-200 mg / day. in 2 doses. There are prolonged forms of metoprolol tartrate: Egilok® Retard tablets 50 and 100 mg, dosage regimen - 50-200 mg / day. once.

• Metoprolol succinate is a retarded dosage form with a sustained release of the active substance, due to which the therapeutic effect of metoprolol lasts more than 24 hours. It is produced under the trade names: Betalok® ZOK, Egilok® S. Dosage regimen - 50-200 mg / day. once.

Bisoprolol (Concor®, Aritel®, Bidop®, Biol®, Bisogamma®, Cordinorm, Coronal, Niperten, etc.)

Perhaps the most common β-blocker today. It does not have BCA and membrane stabilizing effect. Cardioselectivity index - 1:75. It is allowed to take bisoprolol in diabetes mellitus (with caution in the decompensation phase). Less pronounced rebound syndrome. The dosage regimen is individual - 2.5-10 mg / day. in one go.

Betaxolol (Lokren®)

It has a weak membrane-stabilizing effect. Does not have a VSA. Cardioselectivity index -1:35. Works for a long time. Dosing regimen - 5-20 mg / day. once.

III generation - β-blockers with vasodilating (vasodilating) properties

The most clinically important members of this group are carvedilol and nebivolol.

Carvedilol (Vedicardol®, Acridilol®)

Non-selective β-blocker without ICA. Expands peripheral vessels (due to the blockade of α 1 -adrenergic receptors) and has antioxidant properties. Dosing regimen for hypertension - 12.5-50 mg / day. in 1-2 doses.

• How do beta blockers work?
• Modern beta blockers: list

Modern beta-blockers are drugs that are prescribed for the treatment of cardiovascular diseases, in particular hypertension. There is a wide range of drugs in this group. It is extremely important that the treatment is prescribed exclusively by a doctor. Self-medication is strictly prohibited!

Beta-blockers: purpose

Beta-blockers are a very important group of drugs that are prescribed to patients with hypertension and heart disease. The mechanism of drug action is to act on the sympathetic nervous system. Medicines in this group are among the most important drugs in the treatment of diseases such as:

Also, the appointment of this group of drugs is justified in the treatment of patients with Marfan's syndrome, migraine, withdrawal syndrome, mitral valve prolapse, aortic aneurysm and in the case of autonomic crises. Only a doctor should prescribe drugs after a detailed examination, diagnosis of the patient and collection of complaints. Despite the free access to medicines in pharmacies, in no way should you choose your own medicines. Therapy with beta-blockers is a complex and serious event that can both make life easier for the patient and significantly harm her if administered incorrectly.

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Beta-blockers: varieties

The list of drugs in this group is very extensive.

It is customary to distinguish the following groups of beta-adrenaline receptor blockers:

• the heart rate slows down less;
• the pumping function of the heart does not decrease so much;
• peripheral resistance of vessels increases less;
• the risk of developing atherosclerosis is not so great, since the effect on blood cholesterol levels is minimal.

However, both types of medications are equally effective in reducing pressure. There are also fewer side effects from taking these drugs.

List of drugs that have sympathomimetic activity: Sektral, Cordanum, Celiprolol (from the cardioselective group), Alprenol, Trazikor (from the non-selective group).

The following medicines do not have this property: cardioselective drugs Betaxolol (Lokren), Bisoprolol, Concor, Metoprolol (Vazocordin, Engilok), Nebivolol (Nebvet) and non-selective Nadolol (Korgard), Anaprilin (Inderal).

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Lipo- and hydrophilic preparations

Another type of blockers. Lipophilic drugs dissolve in fats. When ingested, these drugs are largely processed by the liver. The action of drugs of this type is quite short-term, since they are quickly excreted from the body. At the same time, they are distinguished by better penetration through the blood-brain barrier, through which nutrients pass into the brain and waste products of the nervous tissue are excreted. In addition, a lower mortality rate has been proven among patients with ischemia who took lipophilic blockers. However, these drugs have side effects on the central nervous system, cause insomnia, depressive states.

Hydrophilic drugs are highly soluble in water. They do not go through the process of metabolism in the liver, but are excreted to a greater extent through the kidneys, that is, with urine. In this case, the type of medication does not change. Hydrophilic drugs have a prolonged effect, since they are not excreted from the body very quickly.

Some drugs have both lipo- and hydrophilic properties, that is, they dissolve equally well in both fats and water. Bisoprolol has this property. This is especially important in cases where the patient has problems with the kidneys or liver: the body itself “chooses” the system that is in a healthier state to remove the drug.

Typically, lipophilic blockers are taken with or without food, while hydrophilic blockers are taken before meals and with plenty of water.

The selection of a beta-blocker is an extremely important and very difficult task, since the choice of a particular drug depends on many factors. All these factors can only be taken into account by a qualified specialist. Modern pharmacology has a wide range of really effective drugs, so the most important priority for the patient is to find a good doctor who will correctly select the appropriate treatment for a particular patient and determine which medicines will be best for him. Only in this case, drug therapy will bring results and literally prolong the life of the patient.

Content

One of the Nobel Prizes in 1988 belongs to D. Black, a scientist who developed and conducted clinical trials of the first beta-blocker - propranolol. This substance began to be used in medical practice in the 60s of the 20th century. Modern cardiology practice is impossible without the use of beta-blockers for hypertension and heart disease, tachycardia and stroke, arterial disease and other dangerous pathologies of the circulatory system. Of the 100 stimulants developed, 30 are used for therapeutic purposes.

What are beta blockers

A large group of pharmaceuticals that protect the heart's beta receptors from the effects of adrenaline are called beta-blockers (BBs). The names of medicines containing these active substances end in "lol". They can easily be chosen among medicines for the treatment of cardiovascular diseases. Atenolol, bisoprolol, propranolol, timolol and others are used as the active substance.

Mechanism of action

In the human body there is a large group of catecholamines - biologically active substances that have a stimulating effect on internal organs and systems, triggering adaptive mechanisms. The action of one of the representatives of this group - adrenaline is well known, it is also called a stress substance, the hormone of fear. The action of the active substance is carried out through special structures - β-1, β-2 adrenoreceptors.

The mechanism of action of beta-blockers is based on the inhibition of the activity of β-1-adrenergic receptors in the heart muscle. The organs of the circulatory system respond to this effect as follows:

• the heart rate changes in the direction of decreasing the frequency of contractions;
• the force of heart contractions decreases;
• decreased vascular tone.

In parallel, beta-blockers inhibit the action of the nervous system. So it is possible to restore the normal functioning of the heart, blood vessels, which reduces the frequency of angina attacks, arterial hypertension, atherosclerosis, coronary disease. Reduces the risk of sudden death from a heart attack, heart failure. Advances have been made in the treatment of hypertension and conditions associated with high blood pressure.

Indications for use

Beta-blockers are prescribed for hypertension and heart disease. This is a general characteristic of their therapeutic action. The most common diseases for which they are used are:

• Hypertension. Beta-blockers for hypertension reduce the load on the heart, its oxygen demand decreases and blood pressure normalizes.
• Tachycardia. With a heart rate of 90 beats per minute or more, beta-blockers are the most effective.
• Myocardial infarction. The action of the substances is aimed at reducing the affected area of ​​the heart, preventing relapse, and protecting the muscle tissue of the heart. In addition, drugs reduce the risk of sudden death, increase physical endurance, reduce the development of arrhythmias, and contribute to myocardial oxygen saturation.
• Diabetes mellitus with cardiac pathologies. Highly selective beta-blockers improve metabolic processes, increase tissue susceptibility to insulin.
• Heart failure. Drugs are prescribed according to a scheme that involves a gradual increase in dosage.

The list of diseases for which beta-blockers are prescribed includes glaucoma, various types of arrhythmia, mitral valve prolapse, tremor, cardiomyopathy, acute aortic dissection, hyperhidrosis, complications of hypertension. The drugs are prescribed for the prevention of migraine, varicose bleeding, for the treatment of arterial pathologies, depression. Therapy of these diseases involves the use of only some BBs, since their pharmacological properties are different.

Classification of drugs

The classification of beta-blockers is based on the specific properties of these active substances:

1. Adrenaline receptor blockers are able to simultaneously act on both β-1 and β-2 structures, which causes side effects. Based on this feature, two groups of drugs are distinguished: selective (acting only on β-1 structures) and non-selective (acting on both β-1 and β-2 receptors). Selective BBs have a feature: with increasing dosage, the specificity of their action is gradually lost, and they begin to block β-2 receptors as well.
2. Solubility in certain substances distinguishes groups: lipophilic (soluble in fat) and hydrophilic (soluble in water).
3. BB, which are able to partially stimulate adrenoreceptors, are combined into a group of drugs with internal sympathomimetic activity.
4. Adrenaline receptor blockers are divided into short-acting and long-acting drugs.
5. Pharmacologists have developed three generations of beta-blockers. All of them are still used in medical practice. Preparations of the last (third) generation have the least number of contraindications and side effects.

Cardioselective beta-blockers

The higher the selectivity of the drug, the stronger the therapeutic effect it has. Selective beta-blockers of the first generation are called non-cardioselective, these are the earliest representatives of this group of drugs. In addition to therapeutic, they have strong side effects (for example, bronchospasm). II generation BBs are cardioselective drugs, they have a directed effect only on type 1 cardiac receptors and have no contraindications for people with diseases of the respiratory system.

Talinolol, Acebutanol, Celiprolol have internal sympathomimetic activity, Atenolol, Bisoprolol, Carvedilol do not have this property. These drugs have proven themselves in the treatment of atrial fibrillation, sinus tachycardia. Talinolol is effective in hypertensive crisis, angina attacks, heart attack, in high concentrations it blocks type 2 receptors. Bisoprolol can be taken continuously for hypertension, ischemia, heart failure, and is well tolerated. It has a pronounced withdrawal syndrome.

Internal sympathomimetic activity

Alprenolol, Karteolol, Labetalol - the 1st generation of beta-blockers with internal sympathomimetic activity, Epanolol, Acebutanol, Celiprolol - the 2nd generation of drugs with such an effect. Alprenolol is used in cardiology for the treatment of coronary heart disease, hypertension, a non-selective beta-blocker with a large number of side effects and contraindications. Celiprolol has proven itself in the treatment of hypertension, is the prevention of angina attacks, but the interaction of the drug with a lot of medicines has been revealed.

Lipophilic drugs

Lipophilic adrenaline receptor blockers include Propranolol, Metoprolol, Retard. These drugs are actively processed by the liver. In hepatic pathologies or in elderly patients, an overdose may occur. Lipophilicity determines the side effects that manifest themselves through the nervous system, such as depression. Propranolol is effective in thyrotoxicosis, cardiomyalgia, myocardial dystrophy. Metoprolol inhibits the action of catecholamines in the heart during physical and emotional stress, is indicated for use in cardiac pathologies.

Hydrophilic drugs

Beta-blockers for hypertension and heart disease, which are hydrophilic drugs, are not processed by the liver, they are excreted through the kidneys. In patients with renal insufficiency accumulate in the body. They have a prolonged action. It is better to take medicines before meals and drink plenty of water. Atenolol belongs to this group. It is effective in the treatment of hypertension, the hypotensive effect lasts for about a day, while the peripheral vessels remain in good shape.

Latest generation beta blockers

The latest generation of beta-blockers include Carvedilol, Celiprolol. They have a minimum number of side effects, and you need to use them once a day. Carvedilol is prescribed in complex therapy for chronic heart failure, as a prophylactic against angina attacks, with hypertension. Celiprolol has similar prescriptions, this drug is canceled gradually, for at least 2 weeks.

Treatment of cardiac diseases in modern medical practice is almost impossible to imagine without the use of a special group of drugs - beta-blockers.

The list of diseases for which therapy using these drugs is used is extensive. They effectively normalize blood pressure and heart rate.

However, like any medication, beta-blockers require caution and care during therapy.

Letters from our readers

Subject: Grandma's blood pressure returned to normal!

From: Christina [email protected])

To: site administration

Christina
Moscow

My grandmother's hypertension is hereditary - most likely, the same problems await me with age.

Beta-blockers are used in the treatment of the following diseases:

• a chronic condition of high blood pressure in the body;
• increased pressure against the background of other pathologies;
• rapid rhythm of contractions of the heart muscle;
• pain in the heart with a diagnosed ischemic disease;
• rehabilitation period after a previous heart attack;
• pathological changes in the rhythm of heart contractions;
• functional disorders in the work of the myocardium;
• thickening of the ventricular wall;
• an abnormal increase in the size of the ventricle and septum;
• a condition in which the mitral valve protrudes into the cavity of one atrium at the time of contraction of the other;
• asynchronous contraction of ventricular myocardial cells or the risk of sudden death;
• high level of pressure against the background of the transferred surgical intervention;
• migraine;
• alcohol and drug addiction.

Classification

The drugs in this group have several classifications that divide drugs according to various criteria.

All beta-blockers are divided depending on the characteristics of their effects on receptors:

• non-selective drugs;
• selective drugs.

A group of non-selective agents do not have the ability to select adrenergic receptors for blocking. They affect all structures.

Such an effect on the body manifests itself in the form of a decrease in blood clotting and a decrease in the number of plaques, the level of pressure in the blood vessels also decreases, the rhythm of myocardial contractions normalizes, and cell membranes stabilize.

The most popular drugs among non-selective beta-blockers are:

• Sandinorm;
• Vistagen;
• Korgard;
• Vistagan;
• Trazikor;
• Whisken;
• Sotalex;
• Okumol;
• Obzidan.

The cost of these drugs is very diverse and varies from 50r. up to 1000r. for packing.

Selective beta-blockers work purposefully on a certain type of receptor. The second name of this group is cardioselective. Blocked receptors are located in myocardial cells, lipoid tissue, and also in the intestine.

The representatives of the selective group are:

• metoprolol;
• Tenormin;
• Esmolol;
• Coriol;
• Nebicor;
• Cordanum;
• Vasacor;
• Acecor.

The cost of drugs in pharmacies is varied. It depends on the manufacturer, the concentration of the active ingredient, as well as the number of tablets in the package.

Domestic drugs are much cheaper than foreign counterparts. Their cost, as a rule, does not exceed 250 rubles. Foreign funds have a price above 500 rubles.

In addition to selectivity, the classification can be based on the progressiveness and novelty of the drug. Thus, among the drugs of the beta-blocker group, 3 generations are distinguished.

The 1st generation of drugs is characterized by non-selectivity of action. These include:

• propranolol;
• Sotalol;
• Timolol.

The 2nd generation of drugs of the beta-blocker group includes selective drugs:

• metoprolol;
• Esmolol.

The 3rd generation of drugs combines the means of selective and non-selective effects:

• Talinolol;
• celiprolol;
• Karteolol.

Currently, it is the 3rd generation drugs that are most often used. They differ in the least number of contraindications and.

However, you can not choose your own medicine. This can only be done by the attending physician based on the results of a general examination of the body.

The highest quality and most effective beta blocker

The group of beta-blockers of the 3rd generation occupies a leading position in terms of the effectiveness of action. This is the most modern and progressive type of drugs that act on adrenoreceptors.

The best among them are drugs under the trade name, as well.

Carvedilol is a selective drug. During its administration, there is an effective decrease in the level of pressure in the blood vessels due to the expansion of the lumen, and the number of plaques also decreases.

- combines 2 types of action. It effectively reduces blood pressure and also helps in the fight against heart disease. Nebivolol is more expensive than Carvediol.

How Beta Blockers Affect Blood Pressure

Beta-blockers block the work of special adrenoreceptors in the body, which are located in the cells of the heart muscle tissue, liver, adipose tissue, etc. As a result of a decrease in the activity of receptors, the following changes occur in the body:

• the rhythm of heart contractions slows down somewhat and myocardial cells require less oxygen;
• the process of blood flow in the coronary region is normalized and high-quality nutrition of the heart muscle occurs;
• the substance renin is produced, which reduces peripheral resistance;
• special active biological substances are produced that expand the vascular lumen;
• cell membranes become less permeable to sodium and potassium ions.

All of these processes occur almost simultaneously, due to this, a decrease in blood pressure occurs. Additionally, the effect of normalization of the heart rate and myocardial function is noted.

Instructions for use

The duration of the course of administration, dosage of drugs and the general treatment regimen is determined. In order for the therapy to be effective, the general condition of the patient's body must be taken into account, whether there are any contraindications.

In addition, regular monitoring of the patient's condition is carried out. If side effects are detected, the doctor replaces the medication with similar ones.

During the entire treatment, it is necessary to monitor the readings of blood pressure and heart rate. Even with minor deviations from the norm, you should immediately consult a doctor to adjust the treatment.

Side effects

In some cases, beta-blocker therapy is accompanied by negative side effects:

• feeling of chronic fatigue and increased fatigue;
• violation of the rhythm of heart contractions in the direction of slowing down;
• increased asthmatic manifestations;
• intoxication of the body, which is manifested by nausea and concomitant vomiting;
• decrease in the concentration of glucose in the blood;
• excessive pressure drop in the vessels;
• pathological changes in metabolic processes;
• increased symptoms of lung disease;
• impaired concentration;
• dyspeptic disorders of the digestive system;
• decreased sexual desire;
• the development of inflammatory processes on the mucous membrane of the eyes;
• allergic rashes over the entire area of ​​​​the skin;
• circulatory disorders in the limbs.

If side effects appear during therapy with these drugs, then the drug is stopped taking. The doctor selects more suitable analogues.

Contraindications

• asthma;
• individual intolerance to the components of a particular drug;
• pathology of the heart rhythm in the form of a decrease in the number of contractions;
• violation of the impulse from the atrium to the ventricle;
• insufficient work of the left ventricle;
• vascular diseases;
• low blood pressure.

In addition, beta-blockers should not be taken during pregnancy and during its planning period.

Overdose

If beta-blockers are taken incorrectly, the recommended dosages and duration of treatment are exceeded, an overdose phenomenon may occur. It is accompanied by the following symptomatic manifestations:

• severe dizziness;
• heart rhythm disturbances;
• a sharp decrease in heart rate;
• blueing of the skin;
• convulsions;
• coma.

If drug poisoning occurs due to an overdose, then it is necessary to provide first aid to the victim as soon as possible. It includes:

1. washing the patient's stomach;
2. taking absorbent drugs;
3. emergency call.

Depending on the symptoms, the patient may be prescribed different drugs to normalize the condition. If the heart rhythm is disturbed, the victim is given atropine, adrenaline or dopamine, depending on the characteristics of the pathology.

Difference from alpha blockers

All drugs that inhibit and block the activity of adrenoreceptors are divided into the following groups:

• beta blockers.

Drugs of the alpha group act on the corresponding receptors. Their influence is aimed at simplifying the process of blood flow, which in turn reduces the level of pressure in the vessels. An additional effect when taking alpha-blockers can be considered a decrease in cholesterol levels.

Beta-blockers called drugs that reversibly (temporarily) block various types (β 1 -, β 2 -, β 3 -) adrenoreceptors.

The value of beta-blockers hard to overestimate. They are the only class of drugs in cardiology for which a . In awarding the prize in 1988, the Nobel Committee called the clinical relevance of beta-blockers " the greatest breakthrough in the fight against heart disease since the discovery of digitalis 200 years ago».

Digitalis preparations (Foxglove plants, lat. Digitalis) are called the group cardiac glycosides (digoxin, strophanthin etc.), which have been used to treat chronic heart failure since about 1785.

Brief classification of beta-blockers

All beta-blockers are divided into non-selective and selective.

Selectivity (cardioselectivity) - the ability to block only beta1-adrenergic receptors and not affect beta2-receptors, since the beneficial effect of beta-blockers is due mainly to the blockade of beta1-receptors, and the main side effects are beta2-receptors.

In other words, selectivity is selectivity, selectivity of action (from the English. selective- selective). However, this cardioselectivity is only relative - in high doses, even selective beta-blockers can partially block beta2-adrenergic receptors. Note that cardioselective drugs are stronger lower diastolic (lower) pressure than non-selective ones.

Some beta-blockers also have a so-called BCA (intrinsic sympathomimetic activity). It is less often called SSA (own sympathomimetic activity). ICA is the ability of a beta-blocker partially stimulate beta-adrenergic receptors suppressed by it, which reduces side effects (“softens” the effect of the drug).

For example, beta-blockers with ICA reduce heart rate to a lesser extent, and if the heart rate is initially low, then even sometimes it can be increased.

Mixed action beta-blockers:

• Carvedilol- mixed α 1 -, β 1 -, β 2 -blocker without ICA.
• Labetalol- α-, β 1 -, β 2 -blocker and partial agonist (stimulator) of β 2 receptors.

Useful effects of beta-blockers

To understand what we can achieve from the use of beta-blockers, we need to understand the effects that occur when.

Scheme of regulation of cardiac activity.

Adrenoreceptors and catecholamines acting on them [ ], as well as the adrenal glands, which secrete adrenaline and norepinephrine directly into the bloodstream, are combined into sympathoadrenal system(SAS). Activation of the sympathoadrenal system occurs:

• in healthy people under stress,
• in patients with a number of diseases:
  • myocardial infarction,
  • acute and chronic heart failure (the heart is unable to pump blood. With CHF, shortness of breath occurs (in 98% of patients), fatigue (93%), palpitations (80%), edema, cough),
  • arterial hypertension and etc.

Beta1-blockers limit the effects of adrenaline and norepinephrine in the body, thereby leading to 4 major effects:

1. decrease in the force of contractions of the heart,
2. decrease in heart rate (HR),
3. decreased conduction in the conduction system of the heart
4. reducing the risk of arrhythmias.

Now more on each item.

Decreased force of heart contractions

A decrease in the force of heart contractions causes the heart to push blood into the aorta with less force and create a lower level of systolic (upper) pressure there. Decreased contraction force reduces the work of the heart and, accordingly, myocardial oxygen demand.

Decreased heart rate

A decrease in heart rate allows the heart to rest more. This is perhaps the most important of which I wrote about earlier. During contraction (systole), the muscle tissue of the heart is not supplied with blood, since the coronary vessels in the thickness of the myocardium are pinched. Myocardial blood supply only possible during its relaxation (diastole). The higher the heart rate, the shorter the total duration of periods of relaxation of the heart. The heart does not have time to fully rest and may experience ischemia(lack of oxygen).

So, beta-blockers reduce the strength of heart contractions and myocardial oxygen demand, and also lengthen the period of rest and blood supply to the heart muscle. That is why beta-blockers have a pronounced anti-ischemic action and are often used for treatment of angina pectoris, which is a form of coronary artery disease (IHD). Old name for angina pectoris angina pectoris, in Latin angina pectoris, therefore, the anti-ischemic effect is also called antianginal. Now you will know what the antianginal action of beta-blockers is.

Note that among all classes of cardiac drugs beta-blockers without ICA best reduce heart rate ( heart rate). For this reason, when palpitations and tachycardia(heart rate above 90 per minute) they are the first to be prescribed.

Because beta-blockers reduce heart function and blood pressure, they contraindicated in situations where the heart does not cope with its work:

• heavy arterial hypotension(BP is less than 90-100 mm Hg),
• acute heart failure(cardiogenic shock, pulmonary edema, etc.),
• CHF ( chronic heart failure) in the stage decompensation.

It is curious that beta-blockers must be used (in parallel with three other classes of drugs - ACE inhibitors, cardiac glycosides, diuretics) in treatment of the initial stages of chronic heart failure. Beta blockers protect the heart from overactivation of the sympathoadrenal system and increase life expectancy patients. In more detail, I will talk about the modern principles of treating CHF in the topic of cardiac glycosides.

Reduced conductivity

Decreased conductivity ( decrease in the rate of conduction of electrical impulses along) as one of the effects of beta-blockers is also of great importance. Under certain conditions, beta-blockers may interfere with atrioventricular conduction(will slow down the conduction of impulses from the atria to the ventricles in AV node), which will cause atrioventricular block (AV block) of varying degrees (from I to III).

AV block diagnosis different degrees of severity is put on the ECG and is manifested by one or more signs:

1. constant or cyclic lengthening of the P-Q interval more than 0.21 s,
2. loss of individual ventricular contractions,
3. a decrease in heart rate (usually from 30 to 60).

Stably increased duration of the P-Q interval from 0.21 s and above.

a) periods of gradual lengthening of the P-Q interval with the loss of the QRS complex;
b) loss of individual QRS complexes without a gradual lengthening of the P-Q interval.

At least half of the ventricular QRS complexes fall out.

No impulses are conducted from the atria to the ventricles.

From here advice: if the patient's pulse has become less than 45 beats per minute or an unusual rhythm irregularity has appeared, it is necessary and most likely to adjust the dose of the drug.

In what cases is increased risk of conduction disorders?

1. If a beta-blocker is given to a patient with bradycardia(heart rate below 60 per minute),
2. if originally present violation of atrioventricular conduction(increased time of conduction of electrical impulses in the AV node by more than 0.21 s),
3. if the patient has an individual high sensitivity to beta blockers
4. if exceeded(incorrectly selected) dose of beta-blocker.

To prevent conduction disorders, you need to start with small doses of a beta blocker and increase dosage gradually. If side effects occur, the beta-blocker should not be discontinued abruptly due to the risk of tachycardia (palpitations). You need to reduce the dosage and stop the drug gradually, within a few days.

Beta-blockers are contraindicated if the patient has dangerous ECG abnormalities, for example:

• conduction disorders(atrioventricular block II or III degree, sinoatrial block, etc.),
• too much rare rhythm(heart rate less than 50 per minute, i.e. severe bradycardia),
• sick sinus syndrome(SSSU).

Reducing the risk of arrhythmias

Taking beta-blockers leads to decrease in myocardial excitability. In the heart muscle, there are fewer foci of excitation, each of which can lead to cardiac arrhythmias. For this reason, beta-blockers are effective in the treatment, as well as for the prevention and treatment and ventricular rhythm disturbances. Clinical studies have shown that beta-blockers significantly reduce the risk of developing fatal (fatal) arrhythmias (for example, ventricular fibrillation) and therefore are actively used for prevention of sudden death, including with pathological lengthening of the Q-T interval on the ECG.

Any myocardial infarction due to pain and necrosis (death) of a portion of the heart muscle is accompanied by pronounced activation of the sympathoadrenal system. The appointment of beta-blockers for myocardial infarction (if there are no contraindications mentioned above) significantly reduces the risk of sudden death.

Indications for the use of beta-blockers:

• IHD (angina pectoris, myocardial infarction, chronic heart failure),
• prevention of arrhythmias and sudden death,
• arterial hypertension (treatment of high blood pressure),
• other diseases with increased activity of catecholamines [ adrenaline, norepinephrine, dopamine] in the body:
  1. thyretoxicosis (hyperfunction of the thyroid gland),
  2. alcohol withdrawal (), etc.

Side effects of beta-blockers

Some of the side effects are due excessive action of beta-blockers on the cardiovascular system:

• sharp bradycardia(heart rate below 45 per minute),
• atrioventricular blockade,
• arterial hypotension(systolic blood pressure below 90-100 mm Hg) - more often with intravenous administration of beta-blockers,
• worsening heart failure up to pulmonary edema and cardiac arrest,
• poor blood circulation in the legs with a decrease in cardiac output - more often in older people with atherosclerosis of peripheral vessels or endarteritis.

If the patient has pheochromocytoma (a benign tumor of the adrenal medulla or nodes of the sympathetic autonomic nervous system that secretes catecholamines; occurs in 1 per 10 thousand of the population and up to 1% of patients with hypertension), then beta blockers can even raise blood pressure due to stimulation of α 1 -adrenergic receptors and spasm of arterioles. To normalize blood pressure, beta-blockers must be combined with.

In 85-90% of cases, pheochromocytoma is a tumor of the adrenal glands.

Beta-blockers themselves exhibit antiarrhythmic effect, but in combination with other antiarrhythmic drugs, it is possible to provoke episodes of ventricular tachycardia or ventricular bigeminy (constant alternate change of normal contraction and ventricular extrasystole, from lat. bi- two).

Bigeminy.

Other side effects of beta blockers are extracardiac.

Bronchial constriction and bronchospasm

Beta2-adrenergic receptors dilate the bronchi. Accordingly, beta-blockers acting on beta2-adrenergic receptors narrow the bronchi and can provoke bronchospasm. This is especially dangerous for patients with bronchial asthma, smokers and other people with lung disease. They have increased cough and shortness of breath. To prevent this bronchospasm, risk factors must be taken into account and it is imperative to apply only cardioselective beta-blockers, which in normal doses do not act on beta2-adrenergic receptors.

Decreased sugar levels and worsened lipid profile

Since stimulation of beta2-adrenergic receptors causes the breakdown of glycogen and an increase in glucose levels, beta-blockers may lower sugar levels in the blood with development moderate hypoglycemia. People with normal carbohydrate metabolism have nothing to fear, and patients with should be more careful. Besides, beta blockers mask symptoms of hypoglycemia such as tremor (jitter) and heartbeat (tachycardia), caused by excessive activation of the sympathetic nervous system due to the release of contrainsular hormones during hypoglycemia. note that sweat glands are controlled by the sympathetic nervous system, but they contain M-cholinergic receptors that are not blocked by adrenoblockers. Therefore, hypoglycemia while taking beta-blockers is characterized especially heavy sweating.

Patients with diabetes who are on insulin should be informed of the increased risk of developing when using beta-blockers. For these patients, it is preferable selective beta blockers that do not act on beta2-adrenergic receptors. Patients with diabetes mellitus in an unstable state ( poorly predictable blood glucose levels) beta-blockers are not recommended, otherwise please.

Sexual violations

Possible development impotence(modern name - erectile disfunction), for example, when receiving propranolol within 1 year it develops in 14% of cases. Also noted was the development fibrous plaques in the body of the penis with its deformation and difficulty in erection when taking propranolol and metoprolol. Sexual dysfunctions are more common in people with (that is, problems with potency when taking beta-blockers usually occur in those who can have them without medication).

To be afraid of impotence and for this reason not to take medication for arterial hypertension is a wrong decision. Scientists have found that long-term high blood pressure leads to erectile dysfunction regardless of the presence of concomitant atherosclerosis. With high blood pressure the walls of blood vessels thicken, become denser and cannot supply the internal organs with the necessary amount of blood.

Other side effects of beta-blockers

Other side effects when taking beta-blockers:

• from the side gastrointestinal tract(in 5-15% of cases): constipation, less often diarrhea and nausea.
• from the side nervous system Key words: depression, sleep disorders.
• from the side skin and mucous: rash, urticaria, eye redness, decreased secretion of tear fluid(relevant for those who use contact lenses), etc.
• at the reception propranolol occasionally happens laryngospasm(difficult noisy, wheezing breath) as a manifestation of an allergic reaction. Laryngospasm occurs as a reaction to artificial yellow dye tartrazine about a tablet after 45 minutes after oral administration.

withdrawal syndrome

If you take beta-blockers for a long time (several months or even weeks), and then suddenly stop taking it, there is withdrawal syndrome. In the days following the cancellation, there is palpitations, anxiety, angina attacks become more frequent, ECG worsens, myocardial infarction and even sudden death may develop.

The development of the withdrawal syndrome is due to the fact that during the time of taking beta-blockers, the body adapts to the reduced effect of (nor)adrenaline and increases the number of adrenergic receptors in organs and tissues. In addition, because propranolol slows down the conversion of thyroid hormone thyroxine(T 4) into hormone triiodothyronine(T 3), some of the withdrawal symptoms (restlessness, trembling, palpitations), especially pronounced after discontinuation of propranolol, may be due to an excess of thyroid hormones.

For the prevention of withdrawal syndrome, it is recommended gradual withdrawal of the drug within 14 days. If surgical manipulations on the heart are necessary, there are other schemes for discontinuing the drug, but in any case, the patient should know your medicines: what, in what dosage, how many times a day and how long he takes. Or at least write them down on a piece of paper and carry them with you.

Features of the most significant beta-blockers

PROPRANOLOL (ANAPRILIN)- non-selective beta-blocker without ICA. This is most famous drug from beta blockers. Active briefly- 6-8 hours. Withdrawal syndrome is typical. Fat-soluble, therefore it penetrates into the brain and has calming effect. It is non-selective, therefore it has a large number of side effects caused by beta2 blockade ( narrows the bronchi and increases cough, hypoglycemia, cold extremities).

Recommended for use in stressful situations (for example, before an exam, see). Since sometimes an increased individual sensitivity to a beta-blocker is possible with a rapid and significant decrease in blood pressure, it is recommended that its first appointment be carried out under the supervision of a physician. with a very small dose(for example, 5-10 mg of anaprilin). To increase blood pressure should be administered atropine(not glucocorticoid hormones). For permanent reception propranolol is not suitable, in this case another beta-blocker is recommended - bisoprolol(below).

Atenolol is a cardioselective beta-blocker without ICA. Formerly a popular drug (like metoprolol). It is applied 1-2 times a day. Water-soluble, therefore does not penetrate into the brain. Withdrawal syndrome.

Metoprolol is a non-ICA cardioselective beta-blocker similar to atenolol. It is taken 2 times a day. Atenolol and metoprolol have now lost their importance due to the spread bisoprolol.

BETAXOLOL (LOCREN)- cardioselective beta-blocker without ICA. Mainly used to treat arterial hypertension. It is taken 1 time per day.

BISOPROLOL (CONCOR)- cardioselective beta-blocker without ICA. Perhaps the most important drug to date from the beta-blockers. Convenient form of administration (1 time per day) and reliable smooth 24-hour antihypertensive action. Reduces blood pressure by 15-20%. It does not affect the level of thyroid hormones and blood glucose, therefore it is allowed for diabetes. In bisoprolol, the withdrawal syndrome is less pronounced. There are many on the market bisoprolol different manufacturers, so you can choose an inexpensive one. In Belarus, the cheapest generic today - bisoprolol-lugal(Ukraine).

ESMOLOL - available only in solution for intravenous administration as antiarrhythmic drug. The duration of action is 20-30 minutes.

NEBIVOLOL (NEBILETE)- cardioselective beta-blocker without ICA. It's also a great drug. Causes a gradual decrease in blood pressure. A pronounced antihypertensive effect occurs after 1-2 weeks of administration, the maximum - after 4 weeks. Nebivolol enhances production nitric oxide(NO) in vascular endothelium. The most important function of nitric oxide is vasodilatation. In 1998 was awarded Nobel Prize in Medicine with the wording " For discovering the role of nitric oxide as a signaling molecule in the regulation of the cardiovascular system". Nebivolol has a number additional beneficial effects:

• vasodilating[vasodilating] (from lat. vas- vessel, dilatation- extension),
• antiplatelet(inhibits platelet aggregation and thrombosis),
• angioprotective(protects blood vessels from the development of atherosclerosis).

CARVEDILOL - α 1 -, β-blocker without ICA. Due to the blockade of α 1 receptors, it has vasodilating action and further lowers blood pressure. Less atenolol lowers heart rate. Does not impair exercise tolerance. Unlike other blockers, it lowers blood glucose levels, so it is recommended for type 2 diabetes. Possesses antioxidant properties, slows down the processes of atherosclerosis. It is taken 1-2 times a day. Particularly recommended for treatment of chronic heart failure(CHF).

LABETALOL is an α-, β-blocker and partially stimulates β 2 receptors. Well reduces blood pressure with a slight increase in heart rate. Has antianginal effect. Can increase blood sugar levels. In high doses, it can cause bronchospasm, as well as cardioselective beta-blockers. Applied intravenously in hypertensive crises and (less commonly) orally twice a day to treat hypertension.

Drug Interactions

As I pointed out above, combination of beta-blockers with other antiarrhythmic drugs potentially dangerous. However, this is a problem for all groups of antiarrhythmic drugs.

Among antihypertensive (antihypertensive) drugs forbidden combination of beta-blockers and calcium channel blockers from the group verapamil and diltiazema. This is associated with an increased risk of cardiac complications, since all of these drugs act on the heart, reduce the force of contractions, heart rate and conduction.

Overdose of beta-blockers

Overdose symptoms beta blockers:

• severe bradycardia (heart rate below 45 per minute),
• dizziness up to loss of consciousness,
• arrhythmia,
• acrocyanosis ( blue fingertips),
• if the beta-blocker is fat-soluble and enters the brain (for example, propranolol), coma and convulsions may develop.

Help with overdose beta-blockers depends on the symptoms:

• at bradycardia - atropine(parasympathetic blocker), β 1 -stimulants ( dobutamine, isoproterenol, dopamine),
• at heart failure - cardiac glycosides and diuretics,
• at low blood pressure(hypotension below 100 mm Hg) - adrenaline, mezaton and etc.
• at bronchospasm - aminophylline (efufillin), isoproterenol.

At topical application(eye drops) beta-blockers reduce the formation and secretion of aqueous humor which lowers intraocular pressure. Local beta blockers ( timolol, proxodolol, betaxolol etc.) are used for glaucoma treatment (progressive eye disease due to increased intraocular pressure). Possible development systemic side effects due to the ingestion of anti-glaucoma beta-blockers through the lacrimal-nasal canal into the nose and from there into the stomach, followed by absorption in the gastrointestinal tract.

Beta-blockers are considered possible doping and should be used by athletes with serious restrictions.

Addition about Koraksan

In connection with frequent questions in the comments about the drug Coraxan (ivabradine) I will highlight its similarities and differences with beta-blockers. Coraxan blocks the I f channels of the sinus node and therefore does NOT belong to beta-blockers.

	Coraxan (ivabradine)	Beta blockers
Influence on the occurrence of impulses in the sinus node	Yes, it suppresses	Yes, suppress
Effect on heart rate	Reduces heart rate in sinus rhythm	Reduce heart rate at any rhythm
Influence on the conduction of impulses along the conduction system of the heart	Not	Slow down
Effect on myocardial contractility	Not	Reduce myocardial contractility
Ability to prevent and treat arrhythmias	Not	Yes (used to prevent and treat many arrhythmias)
Antianginal (anti-ischemic) effect	Yes, used in the treatment of stable angina	Yes, used in the treatment of any angina (unless contraindicated)
Influence on the level of blood pressure	Not	Reduces blood pressure and is often used to treat hypertension

Thus, coraxan used to slow sinus rhythm with normal (slightly reduced) blood pressure and the absence of arrhythmias. If a BP is elevated or have cardiac arrhythmias, need to use beta blockers. The combination of Coraxan with beta-blockers is allowed.

More about Koraksan: http://www.rlsnet.ru/tn_index_id_34171.htm

Beta-blockers in the treatment of CHF

(addition dated 07/19/2014)

The group of beta-blockers belongs to the basic (mandatory) for treatment CHF (chronic heart failure). According to the results of clinical trials, currently for the treatment of CHF recommended 4 drugs:

• carvedilol,
• bisoprolol,
• extended form metoprolol succinate,
• in persons over 70 years of age is also allowed nebivolol.

These 4 drugs have proven in clinical trials their ability to improve the condition and increase the survival of patients with CHF.

• atenolol,
• metoprolol tartrate.

The goal of treatment with beta-blockers in CHF is to reduce the heart rate by at least 15% from the baseline to a level below 70 bpm. per minute (50-60). It has been established that a decrease in heart rate for every 5 strokes reduces mortality by 18%.

The initial dose for CHF is 1/8 of therapeutic and slowly rises every 2-4 weeks. In case of intolerance and inefficiency of beta-blockers, they are combined or completely replaced with a blocker of the I f channels of the sinus node - ivabradine(see above Addition about Koraksan).

Read more about the use of beta-blockers in the treatment of CHF in the National guidelines for the diagnosis and treatment of CHF 4th revision, approved in 2012-2013. (PDF, 1 Mb, in Russian).