Arrhythmia
Description:
Change of conditions of formation of excitement of a cardiac muscle or anomaly of ways of its distribution is the cornerstone of arrhythmia. Arrhythmias can be caused by both functional disturbances, and crushing organic lesions of heart. In certain cases inborn features of the carrying-out system of heart are the reason of disturbances of a cordial rhythm. A part in developing of arrhythmia is played by a condition of a nervous system. For example, the mental, emotional pressure causes changes in speed, and often — and in beat cordial reductions, including, and healthy people. Arrhythmia quite often arises at people with diseases central and the autonomic nervous system.
Arrhythmia symptoms:
Under the influence of one or several etiological factors one or several functions of heart are broken:
automatism (automatic generation of impulses cardiomyocytes pacemaker)
excitability (ability of cardiomyocytes to generate action potential in response to irritation)
conductivity (carrying out an impulse on the carrying-out system of heart)
contractility (reduction of sokratitelny cardiomyocytes)
refrakternost (the electric inertness of KMTs some time after carrying out an impulse which is not allowing return of the carried-out impulse and imposing of the subsequent)
abberantnost (a possibility of carrying out an impulse on additional ways of the carrying-out system of heart)
So, the most known mechanisms of disturbances of excitability (ekstrasistoliya, Bouveret's diseases) are:
mechanism of a repeated return entrance of an impulse (re-entry): macro-re-entry (circulation around venas cava, at a WPW-syndrome: from auricles through Kent bunch in a myocardium of ventricles, then through Purkinye's fibers, legs and a trunk of a ventriculonector an atrioventricular node - back in auricles, micro-re-entry (at dostrofichesky and nektrotichesky changes there is an incomplete unidirectional block of carrying out excitement to a myofibril of a working myocardium of auricles or ventricles. But in the same place ability of antidromic carrying out an impulse remains. If the impulse goes in cycles one-two times — there is premature ventricular contraction if three and more — a Bouveret's disease.
uneven repolarization of a myocardium
increase in amplitude of afterpotentials
increase in automatism of the geterotopny centers
Change of conditions of formation of excitement of a cardiac muscle or anomaly of ways of its distribution is the cornerstone of arrhythmia. Arrhythmias can be caused by both functional disturbances, and crushing organic lesions of heart. In certain cases inborn features of the carrying-out system of heart are the reason of disturbances of a cordial rhythm. A part in developing of arrhythmia is played by a condition of a nervous system. For example, the mental, emotional pressure causes changes in speed, and often — and in beat cordial reductions, including, and healthy people. Arrhythmia quite often arises at people with diseases central and the autonomic nervous system.
The different diseases which are followed by disturbance of anatomical structure of heart or the exchange processes happening in it cause types of arrhythmia, various on duration and character, and only the doctor whose conclusions are based on kliniko-electrocardiographic data can establish the diagnosis.
Arrhythmia reasons:
The most frequent reasons of disturbances of a cordial rhythm and conductivity:
1. Cardial reasons:
Ischemic heart disease, including myocardial infarction and unstable stenocardia
Heart failure
Cardiomyopathy
The acquired heart diseases
Inborn heart diseases
Myocardites
Prolapse of the mitral valve
2. Medicinal influences:
Cardiac glycosides
Antiarrhytmic means (pro-arhythmic action)
Diuretics
Sympathomimetics
3. Electrolytic disturbances:
Hypopotassemia
Hyperpotassemia
Hypomagnesiemia
Hypercalcemia and others
4. Toxic influences:
Smoking
Alcohol
Thyrotoxicosis
5. Idiopathic arrhythmias
Treatment of Arrhythmia:
Apply:
Antiarrhytmic drugs
The direct antiaritmik which are usually influencing various ion channels (Amiodaronum, ритмонорм, аллапенин, etc.). Carry a large amount of side effects of these drugs to shortcomings including ability their to provoke disturbances of a rhythm.
The drugs influencing the carrying-out system of heart (glycosides, beta-blockers) influence automatism of cells of heart, urezhat ChSS.
Up-stream therapy, that is elimination of the reason of arrhythmia. As a rule, the basic disease is treated (an ischemic heart disease, endocrine pathology, ionic disturbances, etc.).
Statement of pacemakers
Radio-frequency ablation
