Heart rhythm disorder
In a normal healthy person, the heart contracts rhythmically, that is, pulse waves follow each other at identical intervals and have the same height. This is the rhythm of cardiac contractions. It can be disrupted in the following cases:
1. In case of a disorder in the heart's conductor system.
2. When the normal excitability of nerves innervating the heart( sympathetic and wandering) changes.
3. For violations in the muscle tissue of the atria and ventricles.
The following types of cardiac arrhythmias are distinguished: tachycardia, bradycardia, respiratory arrhythmia, extrasystole.
Tachycardia - faster heart rate to 100-120 beats per minute. Such an increase occurs when the sympathetic nervous system is excited or when the vagus nerve is depressed. Tachycardia can also occur in a healthy person with physical activity, agitation, fright, fever, intoxication, poisoning with morphine, caffeine, nicotine, etc.
The increase in the number of heartbeats always indicates that in the human body not everything is well and should be takenUrgent measures.
Bradycardia. If the number of heartbeats decreases to 40-50 per minute, they speak of bradycardia, a pulse beat.
Most often, bradycardia occurs with an increase in the tone of the vagus nerve( most often with his irritation).This irritation can occur when the nerve is squeezed by a tumor, dropsy, with meningitis. It can be reflex( peritonitis, flatulence, liver and gallbladder disease) or occur with sclerotic lesions of the sinus node( a neural-reflex node regulating the innervation of the heart).
For some perfectly healthy people, a bradycardia can be congenital( Napoleon's pulse did not exceed 40 beats per minute throughout his life).
As a rule, the number of heartbeats is always lower in athletes, divers and people engaged in heavy physical labor.
This pathology includes all changes in the heart that are associated with a violation of the function of automatism, excitability and conduction of the heart, and in some cases, the correct rhythm of contraction of the heart can be preserved. Arrhythmias can occur in almost all organic diseases of the heart. They can also be caused by autonomic( extracardiac) influences. In the development of their specific importance attached to the violation of the exchange of electrolytes, primarily potassium and calcium ions, as well as catecholamines( adrenaline, norepinephrine) in the myocardium.
With sinus bradycardia, the number of heartbeats is reduced to 60 or less per minute, which is characteristic of well-trained athletes. It can be observed with myxedema, jaundice, increased intracranial pressure. If the number of heartbeats is less than 40 per minute, the complete atrioventricular blockade of the heart should be excluded, which is diagnosed by ECG.
Sinus tachycardia is accompanied by an increase in the number of cardiac contractions to 90 or more per minute and is observed quite naturally with physical stress, excitement, and in conditions of pathology - with fever, thyrotoxicosis, heart failure, intoxication, shock and collapse, severe neurasthenia, with patients often presentingcomplaints about the heartbeat. The increase in the heart rate of more than 130-140 per minute makes one suspect paroxysmal tachycardia.
Sinus arrhythmia associated with respiration is a physiological feature of childhood and adolescence. The appearance of it in adults with forced breathing is prognostically favorable. However, sinus arrhythmia, not associated with respiration, indicates heart disease.
To reduce sinus bradycardia, if necessary, you can assign atropine in drops. With pronounced sinus tachycardia, in addition to the treatment of the underlying disease, potassium chloride is additionally used, and in the absence of contraindications( heart failure, bronchial asthma) - anaprilin( obzidan, inderal).
Respiratory arrhythmia .More often this arrhythmia is called youthful, as it usually occurs in healthy children and young men. In adults, respiratory arrhythmia can occur with neurotic conditions, severe exhaustion, or in a state of recovery from a serious illness.
The essence of arrhythmia is that when you inhale, the number of cardiac contractions increases, and when you exhale, it decreases. As a result, heart contractions become arrhythmic. This kind of arrhythmia eventually passes and does not need treatment.
Heart pulses that occur in the sinus node pass through the heart's conductor system and cause atrial and ventricular contractions at absolutely uniform intervals.
Extra( or additional) abbreviations can appear in case of receiving additional pulses that can occur at any point of the wire system. Extrasystoles are divided into atrial-ventricular, sinus and ventricular. After each extrasystole, the resting interval of the cardiac muscle( diastole) usually lengthens. Extrasystoles most often occur through a certain number of normal contractions of the heart. They can occur after each 4,10,12 stroke.
Extrasystoles are usually perceived by patients as heart disruptions. The cause of their occurrence can be scar or inflammatory changes in the tissue of the heart muscle( after a heart attack, with myocarditis, diphtheria, typhus, etc.).Extrasystoles can also occur in perfectly healthy young people during puberty, often they occur in smokers and people with increased nervous excitability. This type of extrasystoles can be easily eliminated even without medication( gymnastics, water procedures, etc.).
Extrasystolia is characterized by premature excitation and contraction of the heart as a result of the appearance of an additional focus of increased excitability in the cardiac muscle. After such a premature contraction, the next impulse that appears in the sinus node is not realized, and therefore a longer( compensatory) pause follows, which patients often feel, complaining about "fading", interruptions in the work of the heart. Extrasystoles, disturbing the rhythmic activity of the heart, can be detected by examining the pulse or listening to the heart. Extrasystoles can occur rarely, be individual. However, sometimes they appear after each sinus contraction( bigemini) or after every second contraction( trigeminia).With a particularly severe heart pathology, several extrasystoles may follow one after another( group extrasystole).In addition, early extrasystoles that arise very rapidly after the previous contraction, and polytopic extrasystoles, in which there are several foci of excitation, whose localization( atria, ventricles) are possible only with electrocardiography is of great clinical importance. Extrasystoles can occur in all organic heart diseases, especially in cases of coronary disease, malformations, overdose of cardiac glycosides, etc. However, in many cases extrasystoles are noted in individuals without an organic pathology of the heart, especially in neurasthenia, climacteric neurosis.
In the absence of complaints in individuals without organic heart disease, no special treatment is required. With neurasthenia, sedative and tranquilizing agents are indicated( preparations of bromide, valerian, chlordiazepoxide, diazepam).In such patients, as well as with organic damage of the heart, especially with early extrasystoles, the use of anaprilin( inderal), potassium preparations, verapamil( isoptin), lidocaine is indicated. It is especially important to carry out this treatment for acute myocardial infarction, accompanied by early extrasystoles.
This is a sharp violation of the rhythm of the heartbeats, characterized by the appearance of random reductions without any regularity. There is atrial fibrillation with thyroid diseases( thyrotoxicosis), cardiosclerosis, sometimes with hypertension.
Atrial fibrillation may be as bradycardic( the number of heartbeats is up to 80 per minute), and tachycardic( the number of heartbeats reaches 100).Often with atrial fibrillation, pulse waves have an unequal value. This is because full-fledged contractions of the heart alternate with contractions that occur when there is insufficient filling of the blood of the heart. Therefore, the amount of blood discharged into the vessels is inadequate, the organs and tissues experience oxygen starvation, and heart dyspnea arises.
At cardiosclerosis, atrial fibrillation has a permanent character.
Atrial fibrillation usually occurs as a result of atrial fibrillation, in which the common atrial systole is replaced by random excitation and contraction of individual muscle fibers or groups thereof. Significantly less frequent is the so-called atrial flutter, in which they contract at a frequency of up to 300 per minute without a diastolic pause, but only a part( every third, every fourth, etc.) of these pulses is carried to the ventricles. At fibrillation of the atria, ventricular contractions are arrhythmic, which is determined by the pulse or by auscultation of the heart in the form of random heartbeats. With the fluttering of the atria, the right heart rhythm can be maintained. At a ciliary arrhythmia a part of heart contractions at weak filling of ventricles is ineffective, i.e. it is accompanied by a small cardiac ejection and absence of a pulse wave. As a result, the number of heartbeats will be greater than the number of pulse waves( pulse deficit).The negative effect on blood circulation in atrial fibrillation is due to the loss of atrial contractions, which reduces the filling of the ventricles, as well as the violation of the ventricular rhythm. Atrial fibrillation occurs most often with.sclerotic cardiosclerosis, mitral stenosis, thyrotoxicosis, less often with pericarditis, cardiomyopathy, alcoholic multiple dystrophy.
Atrial fibrillation may occur as seizures, but more often a constant form is observed, which can persist for many years. With a constant form of atrial fibrillation with a relatively rare rhythm, there is often a complete adaptation to arrhythmia, so that patients may not sense itand maintain ability to work.
Apply the same medicines as with paroxysmal tachycardia, especially anaprilin, verapamil, potassium chloride, with a significant tachycardia - digokgin. With constant form of atrial fibrillation, its elimination is performed only in the hospital by prescribing quinidine or electropulse therapy after special preparation by anticoagulants. If recovery of the rhythm is not indicated, one should strive to reduce the number of cardiac contractions to 70 per minute by prescribing potassium chloride and digoxin.
This disease is characterized by sudden onset of palpitations, when the patient feels sudden tremors at the beginning and at the end of a heart attack. The number of cardiac strokes with paroxysmal tachycardia can reach 200 per minute while maintaining a normal rhythm. It is often impossible to count the pulse of a patient. Seizures can occur 1-3 times a day. But sometimes they are rare -1-2 times a year. The frequency of seizures depends on the cause that caused the paroxysmal tachycardia. There are often cases when the attack does not pass several days, then the patient has a circulatory disorder, edema, cyanosis. During an attack, patients complain of a fluttering heart and experience a fear of death. They are usually pale, the face is covered with a cold sweat. The paroxysmal tachycardia attack ends as suddenly as it began.
The cause of the disease is a violation of the nervous system. In this case, the normal( sinus) rhythm is disrupted and replaced by pulses occurring in the conductor system located below the sinus node.
Paroxysmal tachycardia is characterized by bouts of severe tachycardia( the rhythm reaches 140-190 per minute), which often begin and end suddenly. Attacks last from 1-2 minutes to 2 weeks or more. Paroxysms of tachycardia are accompanied by a feeling of strong palpitation, constriction in the chest, weakness, sweating. With prolonged seizure, especially in patients with a previous severe heart disease, heart failure may occur and progress with stagnation of blood in a small and large circle. With paroxysmal tachycardia, the focus of excitation( the pacemaker) is located outside the sinus node. A great clinical significance from the point of view of the appointment of therapy is the specification of the localization of the pacemaker. At the site of its localization, the atrial, atrioventricular( nodular) and ventricular forms of paroxysmal tachycardia are isolated. Clarification of the localization of the pacemaker with paroxysmal tachycardia is performed by ECG.With frequent repeated paroxysms of tachycardia, the pacemaker is usually the same. Most often paroxysmal tachycardia is observed in organic heart diseases, primarily atherosclerotic cardiosclerosis, mitral defects, etc.
But in many cases it is not possible to establish an organic lesion, especially with supraventricular paroxysmal tachycardia.
With supraventricular( nodal, atrial) paroxysmal tachycardia, you can try to stop the attack by pressing or massaging the bifurcation site of the common carotid artery. First, the right carotid artery is pressed to the spine, and the left carotid artery is ineffective. The use of this technique is unacceptable in elderly patients with sclerotically altered carotid arteries. Sometimes it is effective and recommended straining with a deep breath, squeezed nose, artificially induced vomiting( an effect that causes irritation of the vagus nerve).Medicinal treatment of all forms of paroxysmal tachycardia is desirable to start with a single injection of a large dose of potassium chloride inside( 5-10 g dissolve in 100 ml of water), the administration of anaprilin - 40-60 mg or 5-10 mg iv, in the absence of effect in patientswith supraventricular tachycardia, strophanthin is administered - 0.5 ml of a 0.05% IV solution. In patients with ventricular tachycardia, novocainamide is very effective - 5-10 ml of 10% solution in / m or IV, slowly, aymalin 50 mg IM or IV.For the treatment of supraventricular tachycardias, in addition to anaprilin, large doses of sedatives like valocordin are sometimes used. If this medication is ineffective, it is possible to use electron-pulse treatment, which should not be postponed in case of a prolonged attack. With frequent attacks of tachycardia, the same anti-arrhythmic drugs are used for their prevention, but in smaller doses, for example anaprilin, verapamil, amiodarone 20-40 mg / day.
Fibrillation of the ventricles is accompanied by a lack of effective contraction of the ventricular myocardium and is incompatible with life. In this regard, urgent resuscitative measures are required, including electrical defibrillation. When preparing for it, you usually have to do heart massage, artificial respiration.
Heart blockages are associated with impaired electrical impulses occurring in the sinus node. Heart rhythm disturbances can be caused primarily by atrioventricular blockades, accompanied by impaired passage of the pulse from the atrium to the ventricles. This blockage may be of different degrees: at grade I only a slowing of the passage of the pulse from the atrium to the ventricles is observed, which is manifested by an extension of the P-Q interval on the ECG, at the second degree - along with the prolongation of the P-Q interval, the individual ventricular contractions fall out, which leadsto arrhythmia. Atrial-ventricular blockade of the third degree - complete transverse blockade - is characterized by the fact that impulses from the atria are not conducted to the ventricles. At the same time, the atria contract in a more frequent rhythm typical of the sinus node, and the ventricles - in a more rare( 40-20 per minute) under the influence of pulses emanating from the atrioventricular node or the center of excitability located in the conducting system of one of the ventricles( idioventricular rhythm).The most important clinical phenomenon associated with the emergence of a complete transverse blockade is the Adams-Stokes-Morgani syndrome. At the time of the blockade, when the driver of the rhythm located in the ventricles has not yet started to work, there is an asystole with the appearance of seizures and loss of consciousness caused by a violation of the blood supply to the brain. These same symptoms can appear and with a sharp decrease in the rhythm of the ventricles.
Atrial-ventricular conduction disorder is common in organic heart diseases - rheumatic carditis, atherosclerotic cardiosclerosis, myocarditis, cardiomyopathy. An overdose of cardiac glycosides in these patients can also contribute to the disturbance of atrioventricular conduction.
Adams-Stokes-Morgagni attacks use epinephrine, and during the interictal period - atropine, isadrin( oblipret), euphyllin, small doses of hypothiazide. With frequent recurrences, operative implantation of an artificial pacemaker is shown.
Intraventricular blockade itself can often not clinically manifest itself. It is diagnosed only by ECG in the form of blockade of the right or left leg of the bundle. The blockade of the right leg of the bundle of the Throat often occurs when the right ventricle is damaged, including heart defects, etc. However, it can be an anomaly in the development of the conducting system and in such cases has a favorable prognosis. The blockade of the left leg of the bundle of His is found in ischemic heart disease, cardiomyopathy, myocarditis. It usually indicates an organic pathology of the heart. A progressive impairment within the ventricular conduction can lead to Adams-Stokes-Morgagni attacks.
Prevention of arrhythmias and conduction of the heart consists mainly of the following activities:
combating neuroses and eliminating neurotic conditions;
combating rheumatism and heart valve apparatus lesions;
prevention of atherosclerosis.