Ventricular arrhythmia is a condition in which pathological impulses of excitation occur in the conducting system of the heart, generated not by the sinus node, but by a focus that has arisen below the atrioventricular junction. Moreover, they can be different in frequency, place of occurrence, type of propagation of excitation. This rhythm disturbance is not considered by me and my colleagues as an independent disease, but accompanies pathological changes in the myocardium or other organs and systems.
What it is
Under the influence of various factors, ectopic (abnormal) excitement suddenly begins in the region of the legs of the bundle of His or small Purkinje fibers. This leads to an unplanned contraction of the myocardium. This forms a ventricular impulse, or extrasystole. Cases of the appearance of single additional cardiac contractions against the background of sinus rhythm are noted even in young and healthy people with excitement or an increase in the influence of the sympathetic nervous system.
If this phenomenon becomes frequent and begins to replace the normal contractions of the myocardium, then hemodynamic disturbance occurs with the development of acute heart failure. In the absence of adequate assistance, this leads to the death of a person.
Types and forms
There is a classification of ventricular arrhythmias:
- Tachycardia. It is characterized by the appearance on the ECG of several additional complexes (at least three) with a high frequency of contractions of up to 100 / minute or more. Paroxysm is stable (lasts from 0.5 hour and longer, often turns into flutter and fibrillation) and short-term, when several "pop-up" complexes are recorded on the ECG.
If you want to know everything about tachycardia, we advise you to watch the video below at the link. Causes, symptoms, diagnosis and signs that it is time to see a doctor - about all this in 7 minutes. Happy viewing!
- Extrasystole. The appearance of deformed complexes against the background of a normal rhythm without a P wave. They can be polymorphic and monomorphic. The former come from different sites, and the latter - from one. By the number of consecutive ventricular impulses, single, paired and group extrasystoles are distinguished.
- Fibrillation. It is noted on the cardiogram in the form of inhomogeneous waves as a result of a complete lack of synchronization of contractions. In this case, systole ceases to be effective and cardiac output is impaired. This condition requires immediate resuscitation.
The options for the development of ventricular fibrillation can be presented in the form of a table:
Stage | Duration | Description of abbreviations | ECG sign |
I. Tachysystolic (flutter) | 1-2 seconds | Frequent coordinated | Several "pop-up" complexes with high amplitude |
II. Convulsive | 15-60 seconds | Local, frequent, irregular | The appearance of high voltage waves with different amplitudes |
III. Shimmer | 2-3 minutes | Multiple, irregular in separate areas | The amplitude decreases, the ECG takes the form of waves of different types |
IV. Atony | from 10 minutes or more | The appearance of non-contracting areas | A gradual decrease in amplitude with episodes of isoline registration |
All types of ventricular arrhythmias can transform one into another. Of particular danger are polymorphic, frequent extrasystoles, or prolonged episodes of tachycardia. They most often result in fibrillation.
Causes
A single extrasystolic complex from the left or right ventricle can be recorded in a healthy person and is not considered a pathology. Problems of the appearance of frequent abnormal contractions of the myocardium with hemodynamic disturbances most often arise as a result of severe diseases of the heart and blood vessels. In this case, the reason may be:
- ischemia and its consequences (angina pectoris, cardiosclerosis, heart attack, aneurysm);
- cardiomyopathy;
- inflammation of the myocardium and pericardium;
- heart failure (both chronic and acute);
- hypertonic disease;
- valve disorders;
- surgical intervention.
Non-cardiac causes can also provoke an attack:
- severe lung disease;
- electric shock;
- intoxication as a result of severe poisoning, liver or kidney failure;
- the use of a number of drugs (bronchodilators, cardiac glycosides, diuretics);
- a decrease in blood potassium levels and an increase in calcium.
Predisposing factors for the development of ventricular arrhythmia are bad habits (smoking, drugs, alcohol, large doses of coffee), constant physical and psycho-emotional overload.
Symptoms and Signs
The patient's complaints with this pathology depend on its type. Single and rare extrasystoles from the ventricles are often asymptomatic, and are determined only using Holter monitoring. With an increase in the frequency of episodes of rhythm disturbance, the patient may indicate the following sensations:
- feeling short of breath;
- "Fading" of the heart;
- weakness and dizziness;
- chest pain;
- fear and panic;
- flickering and fluttering accompanied by loss of consciousness.
Ventricular fibrillation is extremely dangerous, accompanied by a sharp drop in pressure. Full contractions are absent, cardiac output is impaired. As a result, the person loses consciousness and death occurs.
On examination, there is a decrease in pressure, pallor of the skin and cyanosis of the nasolabial triangle. The pulse becomes irregular, with fibrillation it can practically not be felt.
ECG diagnostic criteria
On the cardiogram, the extrasystolic ventricular complex appears earlier than usual. It looks deformed, resembling a left or right bundle branch block. In contrast to the ectopic atrial impulse, it has a compensatory pause, as is clearly seen in photo 1.
With tachycardia (from 100 to 200 / minute) emanating from the ventricles, deformed complexes occurring one after the other. At the same time, there is significant ST depression and a negative T wave, this is how signs of ischemia appear as a result of overload and a lack of oxygen supply to the heart (photo 2).
Flutter on the ECG is recorded in the form of a variety of rapidly forming and highly deformed ventricular complexes, which appear without any regularity when flickering (photo 3).
Case from practice: a young woman with frequent extrasystoles
I want to tell you about an interesting case that I observed in a cardiological hospital. A 32-year-old patient was admitted, she complained of occasional pain in the heart, sensations of interruptions; shortness of breath, profuse sweating and weakness appeared against the background of the attacks. Such changes were noted over the past 7 months, deterioration occurred after physical exertion.
Objective examination: pressure 110/65 mm Hg. Art., the skin is pale, the pulse is irregular. Holter monitoring was carried out. During the day, episodes of tachycardia with a frequency of up to 120 beats were noted, 34,456 ventricular extrasystoles were recorded, many of which were paired and group, as can be seen in photo 4.
In connection with the ineffectiveness of antiarrhythmic therapy and the high risk of developing ventricular fibrillation, the question arose of performing surgery. After radiofrequency ablation, the rhythm was restored, clinical symptoms were within normal limits, and exercise tolerance increased.
Treatment
Treatment of ventricular arrhythmias is not carried out when it manifests itself in single extrasystoles and does not lead to hemodynamic disturbances.But most often, therapy for this symptom is necessary, since it accompanies a severe pathology of the heart.
The treatment protocol requires the mandatory prescription of drugs or the use of pacing. Typically, my colleagues and I use the following tools and methods:
- Beta blockers (Bisoprolol, Egilok). They help lower heart rate and restore rhythm, increase exercise tolerance and prevent sudden death in high-risk patients.
- With a frequent and recurrent form of rhythm disturbance, Amiodarone or Sotalol is added to therapy. When I choose between these drugs, I always consider the likelihood of extracardiac complications and the possibility of developing bradycardia.
- If no result is obtained, radiofrequency ablation or implantation of a cardioverter defibrillator is recommended.
In an acute condition with severe hemodynamic disturbance, resuscitation measures are carried out using a defibrillator and indirect heart massage. Used simultaneously intravenous or intracardiac administration of Adrenaline, as well as Lidocaine or Amiodarone.
Doctor's advice: prevention of ventricular arrhythmias
I want to remind you that usually severe forms of rhythm disturbances develop against the background of serious diseases (coronary artery disease, heart failure, increased thyroid function and many others). Timely treatment, disciplined intake of recommended medications and regular visits to a doctor for these pathologies is the only way to avoid the problem of ventricular arrhythmias.
My recommendations for all patients at high risk of this abnormality would be:
- try to avoid situations where there is an imbalance of electrolytes and fluids (vomiting, diarrhea, independent use of diuretics);
- exercise should be done only after consultation and determination of the maximum permissible loads;
- relieve nervous overstrain with sedatives, learn auto-training techniques, visit a psychotherapist.
