paroxysmal tachycardia - a process the sudden appearance of the heartbeat (paroxysmal), characterized by regular rhythm and frequency of more than a hundred strokes per minute and the same abrupt termination of the attack.All this happens under the influence of pulses ectopic properties that replace normal sinus rhythm.In general, these pulses are generated in the ventricles, and the nature of the compound atrioventricular atria.
paroxysmal tachycardia of etiologic and pathogenetic criteria very similar to the beats, so the following several consecutive extrasystoles are seen as short tahikardichesky paroxysm.
paroxysmal tachycardia - a wasteful inefficient work of the heart during blood circulation, so the appearance of paroxysms, which develop as a result of kardiopatologii, become a cause of heart failure.Almost 25% of patients during long-term ECG monitoring fails to reveal paroxysmal tachycardia in different manifestations.
Most of these tachycardia represent fo
In addition, there are several types of paroxysmal tachycardia responsible for the nature of the current tachycardia.It is an acute, chronic or recurring constantly, and continually relapsing form.During the last arrhythmia can take years to cause cardiomyopathy and arrhythmogenic dilatation of character and lack of job circulation.
paroxysmal tachycardia happens as a result of reciprocal re-entry into the SU (sinus node), and also acts as an ectopic and multifocal form.
Typically, the process of sudden heart beat is repeated input pulse and excitement swirling round the type of re-entry.In rare cases a paroxysm occurs as a consequence of abnormal automaticity.However, despite all the processes of this type of arrhythmia, always develops first beats.
paroxysmal tachycardia causes
the direct causes of an attack of paroxysmal tachycardia in young, are the etiological factors of a functional nature, which include a variety of stresses, both mental and physical.It is known that any stress response is always accompanied by an increase in levels of norepinephrine and epinephrine.
At the time of the attack in the form of paroxysmal tachycardia, and in some cases even before it began, in the blood greatly increases the amount of catecholamines.But in between bouts of these indicators are normalized.Thus, a significant increase in blood catecholamines with simultaneous sensitivity to them ectopic pulses, considered one of the principles of the formation of paroxysmal tachycardia.
also many observations, both clinical and experimental, argue that in the formation of paroxysmal tachycardia, especially supraventricular forms of great importance may be the nervous system in its current state.For example, patients with Wolff-Parkinson-White syndrome after suffering concussion without pathology of the SSS, suffered bouts of paroxysmal tachycardia.In addition, nearly 30% of patients in the vegetative-vascular dystonia and neurasthenia is also observed such attacks.
Quite often paroxysmal tachycardia is considered the result of neuro-reflex irritation, for example, diseases of the digestive system, kidneys, gall bladder, diaphragm.Less frequently, these stimuli come from the mediastinum, genital organs, pancreas, pleura, lung and spine, causing paroxysms of tachycardia.
for paroxysmal tachycardia ventricular shape is typical occurrence in severe cardiac lesions.Developing ischemia in various organs, not just the heart muscle becomes a cause of coronary atherosclerosis, which facilitates the process exciting occurrence of ectopic foci in the myocardium with a very large automatism.
a result of complications of myocardial infarction may occur in rare cases, atrial paroxysmal tachycardia, which is recorded at three percent of patients.In addition, almost half of the patients defined short paroxysms.More often reveal ventricular paroxysmal tachycardia (20%).
also cause the development of paroxysmal tachycardia may act and other pathologies such as myocardial infarction, chronic coronary insufficiency, angina pectoris, hypertension, various heart defects, myocarditis, severe infection.Against the background of allergies and thyrotoxicosis this arrhythmia is rarely found.
Factors contributing to the occurrence of paroxysmal tachycardia are drugs that occupy almost the leading position, influencing the attack.For example, digitalis preparations this cause tachycardia, which is characterized by severe course and often ends with the death of the patient (70%).Also, paroxysmal tachycardia may occur in the treatment of large doses of procainamide and quinidine.In this case, the ectopic foci formed by the imbalance between the potassium that is contained inside and outside the cells.
Furthermore, this type of arrhythmia often develops as a result of heart surgery, when applying therapy electroimpulses and insertion of the catheter into the heart cavity.Sometimes paroxysmal tachycardia preceded VF (ventricular fibrillation).
paroxysmal tachycardia symptoms
Symptoms of paroxysmal tachycardia and starts and ends always in the form of a sudden paroxysmal attacks, which in some cases last for a second, and sometimes - day.This type of arrhythmia characterized by a heart rate of 120-200 beats.per minute which exceeds the rate almost doubled.
Clinically, two types of paroxysmal tachycardia: extrasystolic essential and that explains the place of localization of pulses and are supraventricular and ventricular shape.On the electrocardiogram, these do not differentiate paroxysmal tachycardia.
Esentsialnaya form of paroxysmal tachycardia begins an attack, which also ends without previous and following it extrasystoles.
extrasystolic form is a type of paroxysmal tachycardia between episodes that reveal the beats with a rare frequency and form extrasystolie a paroxysmes tachycardiques.They usually occur momentarily, and can sometimes last for weeks.
for supraventricular tachycardia peculiar right rhythm on the electrocardiogram observed unmodified complex QRS.
patients impose a variety of complaints.Sometimes there is a feeling of paroxysmal tachycardia slight indisposition, more often there is a very strong sense of compression of a paroxysm, and chest pain, and shortness of breath and then manifests itself.
With long protracted attacks, shortness of breath is a law, and if they continue to attack until several days marked the development of congestion in the liver.
At ventricular paroxysmal tachycardia, which has a more serious clinical value, there is not quite the right rhythm, both in supraventricular.When calculating the pulse rate determined by the difference in almost seven hits and no change of rhythm at the time of pressure on the carotid sinus.Complexes QBS changed, and P-wave, which are the normal frequency superimposed on these systems, so they are very difficult to detect on an electrocardiogram.
Basically the patient feels the beginning of the heartbeat as a push in this area, which goes into an accelerated heartbeat.The attack of paroxysmal tachycardia can cause whirling head, the noise in my head and a sense of contraction of the heart.Quite rarely noted transient neurological symptoms as hemiparesis and aphasia.
With this pathological condition the phenomena of vegetative-vascular dystonia.After the attack is over, the patient is polyuria, during which a large amount of urine, having a low density.
In cases of prolonged flow attack point drop in blood pressure, develops weakness and fainting.
It is difficult to carry paroxysmal tachycardia patients having various forms kardiopatologii.For example, ventricular tachycardia, paroxysmal, in which the heart rate reaches 180 strokes may cause the development of ventricular fibrillation.
paroxysmal supraventricular tachycardia
This is a group of diseases involving rhythm disturbance, which can be a source of the atrioventricular node, the sinus node and atrium.In the formation of reciprocal forms of this disease may be additional ways to participate.As a rule, supraventricular arrhythmias have a slight prevalence in the ratio of two cases per thousand people, and with a higher priority among women almost doubled.
Generally, supraventricular paroxysmal tachycardia is classified into several types.
When spontaneous sinus tachycardia constantly quickens the heart rate, which is not due to the physical properties of the load, emotional stress, the presence of any disease, after treatment with drugs or toxic substances.It is believed that the reasons for its occurrence are enhanced automaticity SU and violations of his work in terms of the nature of neurohumoral regulation.Clinically, this manifests itself as a form of tachycardia asymptomatic in some patients, and total disability in others.Patients often complain about the presence of frequent heartbeat, chest pain, shortness of breath, dizziness, and the appearance of syncope.In conducting the survey, except for heart rate over a hundred beats per minute, significant other violations can not be detected.This distinguishes the spontaneous sinus tachycardia, as a kind of POT from accelerated sinus rhythm.
Sinus nodal reciprocating tachycardia is characterized by paroxysmal quickening rhythm of eighty to one hundred and twenty beats per minute.Such heart rate at the time of attack mainly observed in patients who have in the presence of sinus bradycardia, as the initial pathology.The causes of this disease are considered tachycardia SSSThis type of arrhythmia and affects both sexes equally and occurs in adults and in children, but most often in middle-aged and elderly.Symptoms paroxysms expressed little, and it is associated with short duration, low heart rate and hemodynamic minor infractions.Paroxysm sometimes manifests as heart rate, labored breathing or whirling head and rarely characterized by loss of consciousness.In these patients, the attack is diagnosed pronounced sinus bradycardia.
focal atrial tachycardia is characterized by a focus drive, from which emanates the rhythmic impulses to the center of both atria.As a rule, this center is in the veins of the lungs and crista terminalis.This paroxysmal tachycardia detected in patients with chronic cardiopulmonary disorders, infectious lesions of myocardial infarction, cardiomyopathy, and rarely in the absence of heart disease.Triggers an paroxysms hypokalemia, hypoxia, Eufillin overdose Digitalis, alkalosis and acidosis and hyperextension of the atria.Symptoms of paroxysmal tachycardia consists of the clinical manifestations of the underlying disease, but the acceleration of the rhythm of the heart leads only to exacerbate existing heart failure.Against the background of high ventricular rate decreases in blood pressure, so there is shortness of breath, and then revealed edema in the legs.If you violate electrolyte metabolism, intoxication glycosides, the patient's condition becomes worse.The patient weakens, loses his appetite, his nausea, vomiting, and broken open vision.
Atrial politopnye (multifocal) tachycardia is detected the presence of several ECG P waves, which differ among themselves and with the changes in heart rate.This arrhythmia occurs when lung pathology with the existing disturbances in the form of electrolyte imbalance and hypoxia.Glycoside intoxication may also contribute to this paroxysmal tachycardia.It is believed that this arrhythmia is a result of enhanced automaticity SU.
Atrioventricular nodal tachycardia is the most frequent supraventricular tachycardia.The average age of destruction - 32 years old, often sick female.This arrhythmia develops in the presence of heart defects, coronary artery disease, hypertension, as well as in people without heart disease.Provoking this pathology are: stress, smoking, alcohol, coffee, cardiac glycosides and exercise.
Symptoms depend on the duration of an attack, heart rate, reduced ability of the heart muscle, coronary circulation, and psycho-emotional state of the patient.Many patients clearly define the beginning and end of the attack.It is stronger heartbeat characteristic weakness, and then felt cold extremities, patients start to sweat profusely, feeling of heaviness in the head, and sometimes they have it starts spinning, develops intestinal peristalsis, turning into diarrhea.In some cases, there is excitement, anxiety, chest pain, and shortness of breath.With decreasing CB reduced blood pressure, symptoms of cerebral ischemia and the person loses consciousness.Sometimes it formed pulmonary edema, and cardiogenic shock.
Paroxysmal ventricular tachycardia
This type of paroxysmal tachycardia starts quite suddenly and also stops.It called ventricular tachycardia paroxysmal pathology centers of automaticity in the ventricles.Thus heart rate reach more than one hundred beats per minute.Paroxysmal ventricular tachycardia occurs mostly among males (nearly 70%).
reasons for the formation of paroxysmal ventricular tachycardia are various pathologies such as coronary heart disease, cardiosclerosis after myocardial infarction, cardiomyopathy of alcoholic origin, cardiac defects, hypokalemia, stressful situations, myocarditis, cardiac glycosides, a congenital abnormality PZHT, arrhythmogenic dysplasia ventricular prolapsemitral valve.
Symptomatic picture depends on low cardiac output and is characterized by a pale complexion and low pressure.Heart rate is usually regular 100 to 200 per minute, but usually - 150-180 beats per minute.
An electrocardiogram is not defined P wave and signs that allow you to reliably diagnose ventricular paroxysmal tachycardia.There are normal, the same QRS complexes on the background changed complete capture of the ventricles, which say that goes to the ventricles sinus impulse.
Applying ECG study emit certain types of this arrhythmia: stable at 140-250 bpm heart rate.min.with ventricular complexes of the same type;repeated, in which episodes of paroxysmal presented in groups of three, five or ten complexes QRS;slow - heart rate of 100-140 beats per minute, which lasts up to 25 seconds (almost thirty QRS).
Typically, ventricular tachycardia paroxysmal divided into a bidirectional VT, pirouette, polymorphic and recurrent.All data are characterized by the occurrence of arrhythmias is without symptoms and clinical signs bright manifesto.They can start with the frequent occurrence of the heartbeat, perceived by the patient and the development of severe forms of hypertension, DOS, angina and syncope states of nature.
to diagnose ventricular paroxysmal tachycardia techniques used physical examination, ECG, Holter monitoring, electrophysiological examination of the heart and the inside of the esophagus, exercise test and echocardiography.