PVCs - this is one of the types of arrhythmias, which are premature, arising out of the lineup, ventricular contraction.For the ventricular arrhythmia is characterized by a sense of violations of the heart in the form of failure, weakness, circling the head, anginal pain character and lack of air.This type of arrhythmia is set after listening to the heart, ECG monitoring and Holter.And for an extraordinary treat ventricular used sedative drugs, beta-blockers, and antiarrhythmics.
PVCs comprise almost 62% of all extrasystolic arrhythmias.This heart rhythm disorder is a consequence of premature excitation of the heart muscle, which is based on the Purkinje fibers and bundle branch block.
On the basis of this form of ECG heart beat, introducing the single beats determined in 5% of healthy young people, and during the daily monitoring - almost half of the surveyed.In addition, such an arrhythmia recently began to increase sharply with age.
ventricular arrhythmia causes
etiological factors of this extraordinary ventricular contraction is both a lack of organic heart disease, and their availability.For the first case characterized by stress, smoking, alcohol, coffee, tea, which increases the activity of the sympathetic system and adrenal.But most healthy people beats appear without much apparent reason.
However, despite the fact that the characteristic shape of arrhythmic contraction occurs on the background of many of the organic nature of the cardiac lesions, one of the main causes of ventricular arrhythmia is still considered a CHD.In carrying out monitoring during the day such arrhythmia observed in 90% of patients.
On the occurrence of ventricular influence available in patients with acute coronary syndromes, especially myocardial infarction.Among the common causes of ventricular arrhythmia can distinguish pericarditis and myocarditis, cardiomyopathy and an increase of the heart, which in its development contribute to hypertrophy of the heart muscle, and ventricular heart failure.In addition, this type of arrhythmia beats are often detected in the pathology of the mitral valve.
also characteristic factors in the formation of an extraordinary ventricular important role played by iatrogenic factors, namely when taking an overdose of cardiac glycosides, beta-adrenostimulyatov and sometimes membranostimuliruyuschih drugs antiarrhythmic action, especially if you have heart disease of organic origin.
ventricular arrhythmia symptoms
This form of extraordinary cardiac ventricular contraction may be asymptomatic or sensations fading heart or stroke as a result of the thrust power cuts postextrasystolic origin.This subjective feelings are not characteristic expression and are not depending on the heart rate and cause of premature beats.With the frequent ventricular arrhythmia in patients with severe heart disease sometimes there is a weakness;pain as angina;may feel dizzy and not enough air to breathe.
At the time of the survey sometimes find expressed presystolic pulsing veins in the neck that occurs when atrial systole once the right on the background of a closed tricuspid due to the characteristic of premature ventricular contractions.This pulsation is called venous pulsation Corrigan.At the same time the pulse of the artery almost palpable, has quite a long pause that occurs after the full compensatory pause properties.
But the appearance of atrial fibrillation, frequent form of arrhythmia and group.Moreover, many patients is difficult to determine the pulse.This is due to its scarcity.When listening to the heart, the first tone changes its sound due to non-simultaneous contraction of the atria and ventricles as well as the oscillation interval P-Q.In addition, the reduction is characterized by a line splitting the second tone.
The main ECG signs of ventricular arrhythmia can be attributed the appearance of the extraordinary changes in the electrocardiogram premature ventricular complex QRS.In addition, this complex is considerably increased in size and deformed;attaching extrasystoles inconsistency in position and the T-wave segment RS-T with respect to the basic QRS complex;no P-tooth before ventricular premature beats, as well as the present, when the characteristic of ventricular beats, the absolute nature of the compensatory pause.
ventricular arrhythmia is sometimes characterized by different clinical course and the same prediction, which will depend on existing cardiac abnormalities organic nature, manifestations and pronounced degree of ventricular myocardium.
However, there is evidence that the extraordinary reduction in the ventricles of the heart, even the most frequent and complex, with the absence of structural abnormalities in patients SSS is not particularly affect the prognosis of this condition.But with existing cardiac lesions organic genesis, the form data arrhythmic reductions significantly increase the percentage of sudden death due to heart disease and general mortality, cause persistent ventricular tachycardia, and a manifestation of their atrial fibrillation.
gradation ventricular arrhythmia
Healthy Heart works automatically, that is, at some point in cardiomyocytes appears exciting pulse, which is then transmitted to the heart muscle infarction.But when there occur various changes melkoochagovogo macrofocal or nature, then there is the re-introduction of momentum and therefore the myocardium is subjected to repeated stimulation.
The heart muscle is considered to be the most vulnerable part of the left ventricle, as there often appear degenerative changes and sclerotic lesions after coronary artery disease or heart attack.Therefore extraordinary beats much more likely to develop it in the left ventricle, while the right ventricle is less susceptible to such changes.It can be concluded that ventricular premature beats - this is an extraordinary contraction of the heart, thanks to its location in the ventricular ectopic impulse.Therefore, re-start of excitation located in the septum between the ventricles, or in its wall, occurs via hearth re-entry.This means that the locus of excitation may occur in any part of the left ventricle and cause ventricular arrythmia.
for prognostic evaluation of these PVCs use classification Lown and Wolf, on which there are five classes of gradation of the arrhythmia.The first class is sporadically occurring ventricular premature beats with a heart rate less than thirty per hour.Therefore, this type of arrhythmia is considered to be harmless, and almost the norm, if a person is not in the presence of cardiac disease.
second class belong to single beats, which are also produced in the ventricles at a rate exceeding thirty per hour.This arrhythmia is somewhat more significant, but rarely seen any consequences.
For the third class is characterized polymorphs extraordinary cardiac ventricular contraction which vary ECG leads.In case of recurrent episodes of arrhythmia characteristic shape appoint specialized treatment.
In the fourth class (A) observed paired heart rate, followed by a sequence, ie a row.In the fourth class (B) - Group of arrhythmia, which are characterized by the repetition of three or five consecutive ventricular premature beats.
And for the fifth grade characterized earlier forms of arrhythmias or «R on T».Moreover, from the third to the fifth grade ventricular arrhythmias are considered high degree of gradation, which can lead to ventricular tachycardia and ventricular fibrillation, which can lead to cardiac arrest and death.
But the extraordinary importance of cardiac ventricular low gradation is determined by the presence of some of the symptoms that occur when these arrythmia.Sometimes every second stroke develops this form of arrhythmia, and the patient does it feel.But when extrasystole occurs only two or three times an hour, the patient may feel very bad, until he lost consciousness.Therefore, as an extraordinary form of certain cardiac ventricular life-threatening solved strictly individually for each patient.
This type of arrhythmia occurs in the presence of organic heart disease the nature and without them.By carrying out daily monitoring Holter, ventricular arrythmia is observed in 60% of subjects.And in the absence of heart disease does not have a characteristic influence on the prognosis of arrhythmias.
after myocardial infarction ventricular premature beats in its prevalence is 80%.This pair beats are frequent and have a higher fatality.However, these forms of the arrhythmia are a significant risk factor in contrast to the low left ventricular ejection fraction.
electrocardiographic ventricular arrythmia is extraordinary wide deformed complexes QRS, without preceding P wave and the interval between the mesh complexes may be permanent.In addition, when a variation of heart rate with a common divisor, say parasystole ventricular shape.With this arrhythmia beats are based on the focus of excitation in which no pulses of the sinus node.
ventricular arrhythmias may occur with single heart beat and repetitive sequences (bigeminy), each second QRS complex as trigeminy or third as quadrigemini.
Two consecutive occurring arrhythmia, called the guy and more than three at a frequency of 100 per minute - ventricular tachycardia or unstable form.In addition, ventricular premature beats may have the same or a different shape, that is characterized by monomorphic or polymorphic premature beats.
Basically extraordinary impulses are not conducted in the atrium and sinus node is not discharged, so the resulting pulses are unable to bring in the excitement ventricles as a result of refractory.It is this and becomes the cause of ventricular arrhythmia in the background of the full compensatory pause, that is formed by the interval between extrasystolic teeth R, before and after regular intervals RR.As a result, the extraordinary momentum in the atrium, in the form of retrograde P waves, may drain the sinus node and pause compensatory nature will be incomplete.
At some point the impulse to the atria is subject to blockage in the AV node, and it lengthens the interval PQ or loss contributes to the following complex QRS.This lengthening of PQ interval postextrasystolic explained by the latent form of retrograde in the atrioventricular node.
In cases where after the ventricular arrhythmia is not formed a compensatory pause, then there is interpolated or intercalated form of arrhythmia.
ventricular arrhythmia treatment
main objectives of the treatment of ventricular arrhythmia are that in order to reduce discomfort caused by heart and to warn paroxysms stable form of ventricular tachycardia or ventricular fibrillation.
In that case you need only reduce discomfort, patients are subject to empirical treatment, which focuses on the well-being of patients.As a rule, the opinions on the appointment of the treatment of ventricular arrhythmias, asymptomatic, some contradictory.The use of antiarrhythmic drugs for the treatment of complicated forms of symptomatic arrhythmias without the characteristic pattern, only in the case of the potential dangers of this condition and the likely benefits of providing these drugs.In addition, nearly forty percent of patients as a result of side effects of anti-arrhythmic drugs have to give up these funds.One of the dangers of receiving antiarrhythmic drugs is their arrhythmogenic properties observed in 10% of patients.
mainly ventricular premature in the absence of organic heart disease does not increase the risk of sudden death.Although reduced LV contractility probability of forming a stable ventricular arrhythmia increases slightly, and forecasting of the arrhythmia in respect of sudden death of a minor.
patients who have suffered myocardial infarction and treated as encainide or flecainide, noted the successful elimination of PVCs, but was accompanied by increased mortality is nearly four times as opposed to receiving a placebo.Therefore, given these data, empirical treatment with antiarrhythmic drugs is not recommended.
But indications for hospitalization are first detected ventricular arrhythmia and poor is projected form of arrhythmia.
destination for specialized treatment is required to take into account the class graduation extraordinary cardiac ventricular contraction with heart disease, the nature of the heart muscle dysfunction and severity of the violations, which are potentially fatal to ventricular arrhythmia and death.
presence of symptomatic patients without evidence of cardiac abnormalities, even with high grade of B. Lown not prescribe a particular treatment.Therefore, we should be able to explain to the patient that the arrhythmia can be benign, while recommending a diet enriched in potassium with the exception of nicotine, alcohol, coffee, strong tea varieties, and in cases of physical inactivity need to increase physical activity.It is with these events and begin to treat asymptomatic ventricular arrhythmia.And only when they prove ineffective, proceed to the appointment of drugs.
to treat such patients to first-line drugs, include funds sedation (eg, diazepam, or herbal) and beta-blockers.In a significant number of patients they have a positive effect by reducing the heart rate under the influence of sedatives and reduced power postextrasystolic reduction.
Generally, the purpose of beta-blockers to begin propranol (Inderal, obzidan) in small doses, and if necessary increase them, controlling the heart rate.In some categories of patients with ventricular arrhythmia at the time when the reduced frequency rate, increasing the number of premature beats.But in the presence of bradycardia in the outcome, as a consequence of increased tone of the parasympathetic division of the ANS, especially among young people, is used for the relief of ventricular arrhythmia drugs belladonna and Itropium.
In very rare cases, with ineffective treatment sedatives, as well as to adjust the tone of the ANS and impaired well-being of patients resorted to the appointment disopyramide, procainamide, quinidine, mexiletine, and flecainide Propavenona.In addition, data Membrane stabilizing agents, unlike beta-blockers, have significant side effects, so they should be avoided in their assignments if possible.Also, sedatives and well-blockers are used to treat this form of arrhythmia with the characteristic symptoms on a background of mitral valve prolapse.And the use of antiarrhythmic drugs of the first class in this case is also acceptable only under highly disturbed state of health.