SVT - is one form of arrhythmia, the cause of which is becoming a failure in the electrical conductivity, the regulation of the rate of contraction of the heart.Supraventricular tachycardia have a favorable course compared with ventricular.Supraventricular tachycardia, a form much less associated with organic heart damage and dysfunction of the left ventricle.Yet supraventricular tachycardia is considered as a condition life-threatening due to the likelihood of some presinkope or syncope and sudden arrhythmic death.
In the heart of a physically healthy person, each reduction is a consequence of an electrical pulse which is generated by the heart pacemaker, which is located in the right atrium.Thereafter, a pulse is applied to the next node, from where it is thrown to the ventricles.During the occurrence of supraventricular tachycardia pacemaker can not control the reduction of the formation of abnormal conduction pathways or extension unit, leading to failure of the heart rhythm.
supraventricular tachycardia causes
supraventricular tachycardia, signs of which - a very high frequency of contractions of the heart muscle (up to two hundred and fifty times in a minute), a sense of fear, has several causes (premises) development.At the youthful age of tachycardia can be functional.This tachycardia cause a variety of stressful situations, excitement, strong emotions.
In the event of supraventricular tachycardia important plays that the condition of the human nervous system.The impetus for the development of supraventricular tachycardia may be neurasthenia, climacteric changes cardiopsychoneurosis, contusion.The attack may happen due to reflex influences kidneys, diaphragm, gall, stomach.Much less a reflex effect on the main organ of the circulatory system have the spine, lungs and pleura, pancreas, and reproductive organs.
supraventricular tachycardia can cause some drugs, especially procainamide, quinidine.Also is a very dangerous overdose of cardiac glycosides, which can cause severe supraventricular tachycardia, which is half of the reported cases ends lethally.Paroxysms arise in this case because of the significant changes in the level of potassium in the body.There are a number of reasons, in some cases leading to tachycardia: hypertension, chronic infectious process, thyrotoxicosis.The attack may occur on the operating table during surgery on the heart during treatment of electrical impulses.In some cases, it may be preceded by a paroxysm of atrial fibrillation.
supraventricular tachycardia in children and young people is sometimes a manifestation of congenital heart defect pathways - syndrome, Wolff-Parkinson-White syndrome.When this disease atria and ventricles receive additional way of located outside the atrioventricular node.Because of this accelerating excitation of the ventricles, causing SVT.
supraventricular tachycardia symptoms
main symptom of supraventricular tachycardia is a rapid acceleration of the sharp contraction of the heart muscle.During an attack of the heart can be reduced at a rate of one hundred fifty to two hundred and fifty times in one minute.Often can be traced, the higher the heart rate, the more intense and brighter symptoms appear.
manifestations of the disease in each case have certain distinctive features.They are caused by the presence or absence of organic myocardial damage, located in the organ pathological pacemaker, the state of flow, duration of the attack, the condition of the heart muscle.During supraventricular tachycardia in a patient can occur dizziness.Frequent symptoms of this disease are both pain in the chest or neck, shortness of breath may occur.Most supraventricular tachycardia accompanied by a sense of fear, panic and anxiety.Painful symptoms can appear oppressive feeling in the chest (oppression).
If the attack lasted for a long time, a person may be signs pointing to the occurrence of cardiovascular disease.This dangerous condition can be diagnosed by a simple and very characteristic features: the occurrence of difficulties in the implementation of inspiration, the development of swelling in the arms, legs, face, appearance acrocyanosis (the fingertips and toes, as well as the portion of the mouth and nose become pale bluish hue).A long bout of tachycardia may result in fainting.In this state, a person needs help doctors.
suspect that SVT is the reduction of blood pressure.Very often the pressure drops, if the attack lasts.That is why a man with a long bout of tachycardia sure to measure the pressure, as its critical fall could seriously endanger human life, cause the collapse.
is important to know that people with low pressure to a greater extent susceptible to the emergence of supraventricular tachycardia.This is due to the fact that at low pressure in the blood flow to the arteries it bodies decreases and the body is trying to fix it by means of amplification of heartbeats.That is why SVT so common in hypotensive patients.
If a person is suffering for a long time this form of tachycardia and seizures occur frequently, it must be examined, because without the necessary treatment may be heart failure and dilated cardiomyopathy.
supraventricular tachycardia ECG
on ECG QRS supraventricular tachycardia in any strain lacking.In rare cases, its shape is still subject to change due to aberrant conduct.Re-entry in the atrioventricular node - a common cause of it is supraventricular tachycardia (on this form there are six out of ten cases, supraventricular tachycardia).It is believed that the re-entry in the atrioventricular node arises from the fact that he dissociates longitudinally into two paths, a separation between functional.When fit tachycardia anterograde impulse passes from one of these pathways, and retrograde - the second.That is why the atria to the ventricles are excited at the same time, the retrograde P-QRS teeth merge with and become invisible, or ECG recorded immediately after the complex.
If the blockage has occurred in the atrioventricular node, re-entry is interrupted.But in the bundle branch block or below can in no way affect the nazhdeludochkovuyu tachycardia.These blockades are very rare, especially in young patients, which is why the occurrence of atrioventricular block during supraventricular tachycardia testifies against re-entry (AV nodal reciprocating tachycardia).
Rare cause of supraventricular tachycardia becomes re-entry in the sinus node.In this case, the pulse propagates within the sinus node, so the tachycardia P wave their shape is no different from the P wave to sinus rhythm.The pulse propagation atrioventricular node does not participate, it is for this reason that the size of the interval PQ, absence or presence of atrioventricular block depend solely on the properties of the atrioventricular node.
Every twentieth case of supraventricular tachycardia is caused by re-entry in the atria.Momentum in this case circulates in the atria, with supraventricular tachycardia before QRS registered prong P, which indicates the anterograde pulse propagation in the atria.The chain of re-entry atrioventricular node is not included.That is why AV block has no effect on this form of supraventricular tachycardia.
reasons for the rare cases of SVT are pockets with increased automatism.Form P wave during tachycardia depends on where the source is ectopic.
supraventricular tachycardia treatment
If a person came supraventricular tachycardia, emergency assistance should be provided immediately.A very effective method is to sample Cermak-Gerringa.The manipulation is performed when the patient is in a horizontal position.It should be for thirty seconds to press your thumb on the sleepy node on the right.It is located at the upper border of the thyroid cartilage in the projection of the inner surface of the upper third of the sternocleidomastoid muscle.As soon as the attack, you must immediately cease pressure on the artery.This test is contraindicated for people in old age with atherosclerosis, hypertension at later stages, as well as in the event of an overdose of funds on the basis of foxglove.
above assay can replace the sample Eshnera-Danini.It is simultaneously a mild pressure on the eyeballs of the patient.This manipulation is only possible in a reclining position.Perform it can not be more than thirty seconds as soon as the effect, the effect is stopped.Sample Eshnera-Danini prohibited if the patient suffers from ocular pathology.Remove supraventricular tachycardia attack will artificially induced vomiting, cool off with cold water, a strong pressure on the upper abdomen.In the event that the impact of the reflex methods to no avail, using medications.
supraventricular tachycardia in our time it is successfully and effectively treated with Verapamil.In order to stop an attack, 0.25% verapamil injected into a vein in an amount of two milliliters.After the attack ended, you must go to the tablet form means.Assign to one tablet 2-3 times a day.If verapamil proved ineffective, instead using beta-blockers (Inderal, whiskey, oxprenolol).During an attack Inderal give intravenous (0.001g for 60-120 seconds).If after a few minutes there is no result, the same dose is administered.Total can do five or ten injections Inderal under the control of hemodynamics and ECG.Inside the means prescribed 1-2 tablets one to three times a day (the dose the doctor picks up).
oxprenolol cupping supraventricular tachycardia injected into a vein at a dose of 0,002 grams.Typically, this amount is sufficient and repeated administration is required.Oxprenolol taken orally two to four tablets per day (0.04 - 0.08 grams).Whiskey used intravenously at a dose of 0,0002-0,001 grams in the form of a dropper or five percent solution of glucose per os, three to six tablets a day (0.015 - 0.03 grams).
often enough to stop the attack, supraventricular tachycardia using procainamide.It is injected into the vein or muscle, five to ten milliliters of ten percent of the drug.You can receive and the inside of 0.5 - 1 gram every two hours until the termination of the attack.It is important to know that the introduction of novokainamid parenterally can lead to disturbances in hemodynamics, including the collapse.
good therapeutic effect in most cases has Ajmaline.This preparation is invaluable in the treatment of critically ill patients who can not give procainamide, quinidine, beta-blockers because of their toxicity and bright hypotensive effect.Ajmaline injected very slowly (about five minutes) to 0.05 grams per milliliters 10-20 five percent sodium chloride or glucose.After the attack has been successfully docked, Ajmaline administered in tablet form (one to two tablets three or four times a day).
If the patient often attacks the lungs concerned supraventricular tachycardia, helps pulse-rate.During the attack you need to drink two drops, and then take the same pills every eight to twelve hours.
quickly relieves SVT such preparation as Trifosadenin.It is administered in a vein rapidly (within one or two seconds).Usually a single injection of charge from one to three milliliters of one percent Trifosadenina.Immediately after administration of the drug into the body in the same vein is necessary to enter ten milliliters of sodium chloride (0.9%), or five percent glucose solution.If within one hundred and twenty seconds, there is no effect, the patient should be given a double dose of this drug.In the first minutes after the injection in humans can begin headache or bronchospasm.Fear of these phenomena is not necessary, because they are transient and quickly pass without consequences.
its effectiveness in attack showed supraventricular tachycardia and Procainamide.This kolyat drug into a vein, introducing very slowly.For infusions take a ten percent solution.The introduction of this tool is best carried out using a special dispenser of drugs.This is necessary in order to prevent the possible development of hypotension.
If supraventricular tachycardia may use esmolol.It ultrashort beta-blocker.First give the patient the drug in a dosage of load (up to five hundred micrograms per kilogram) for sixty seconds.In the next four minutes the drug is administered at the rate of fifty milligrams per kilogram.In most cases, the effect occurs five minutes from administration, supraventricular tachycardia attack passes.If, however, the attack continued and the sick person has not become easier, repeat loading dose esmolol.
If there was a situation where it is impossible completely to be sure that arose supraventricular tachycardia is it best to introduce procainamide or amiodarone.The method of administration procainamide has been described above, amiodarone injected into a vein in an amount of three hundred milligrams of jet.Previously it should be diluted with twenty five percent milligrams of glucose.Sodium chloride (isotonic) used for breeding novokainamid prohibited.
After the attack managed to arrest, supraventricular tachycardia patient prescribed therapy helps prevent relapse.These drugs include various cardiac glycosides and antiarrhythmic drugs.Now it is very popular for outpatient treatment is a combination of Diltiazem Verapamil.
Every patient with supraventricular tachycardia is unique, so the scheme for home care doctor chosen individually.Typically, a physician selects from such drugs as sotalol Etatsizin, quinidine, propafenone, Azimilide Allapinin and some other preparations.Sometimes, the doctor prescribes a monotherapy and in some cases it is necessary to combine several means.
forecast for living for people with supraventricular tachycardia is quite favorable, tachycardia does not affect the duration of a person's life and even as if the patient complies with the recommendation of his doctor.