What is the syndrome of premature excitation of the ventricles

The syndrome of premature excitation of ventricles (other names — syndrome predposlednij, praxitele) in the overall clinical-functional classification of violations of rhythm of the heart refers to combined arrhythmias. This means that the origin of the "mixed" together the processes of violation of conductivity and excitability.

Predposlednii leads to more early "unplanned" contraction of the ventricles. Among the population syndrome is rare in 0.15% of cases. But, if you look at the coordination with other departments, will receive more alarming statistics:

• in patients with paroxysmal tachycardia up to 85%;
• in atrial fibrillation up to 30%;
• when atrial flutter — almost every tenth.

In 30-35 % of cases the syndrome occurs in secret.

A bit of history

Typical signs described for the first time in 1913. The reason for the pathology for a long time, it was considered a kind of blockade of bundle branch block and its branches.

A joint report by L. Wolff, J. Parkinson and P. white in the 1930s laid the Foundation for studies of the pathogenesis of conditions with increased excitability and nerve impulse conduction.

After 2 years, was presented the theory of accessory bundles, which are found on histological sections only in 1942 F. wood.

Active research on the electrophysiology of the cardiac muscle made it possible to definitively establish the localization of additional paths and discover their diversity.

If you go the other way

The origin of the syndrome predposlednij caused by abnormal passage of the impulse atypical ways.

From the sinus node located in the right atrium, the excitation is sent in several bunches in the atrioventricular node, the path cost in atrial myofibrils. After passing through the atrioventricular connection, goes to the area of his trunk, on his legs. Next Purkinje fibers reaches the tops of both ventricles of the heart.

The study of the conduction system showed the presence of additional shorter paths along which the excitation can reach the ventricles in a roundabout way. These include:

• bundle of Kent (goes from the Atria to both ventricles);
• beam James (from the Atria into the lower part of the atrioventricular node and trunk-branch block);
• fiber Mahama (depart deep into the ventricular myocardium of the heart from the trunk-branch block);
• beam Brechenmacher (trifascicular) directly connects the right atrium and the trunk of his.

Psychologists have identified other ways of holding. Up to a certain time they can be hiding in overall system conductivity. But in the case of activation, capable of conducting nerve impulse in the opposite direction (retrograde) from the ventricles to the Atria. It is also established that up to 10 % of patients with arrhythmias have severalabnormal ways of holding.

ECG-signs of severity depend on the strength of the received predposlednij, permanence of the changed paths of the pulse. It is accepted to allocate following types of the syndrome:

• symptomatic — signs on ECG are kept constantly and do not disappear over time;
• intermittent manifestations of predposlednij are transient (impermanent) character;
• latent — the normal pattern of ECG changes and the signs of predposlednij during provocative tests (exercise, irritation of areas of the vagus nerve) and during paroxysmal rhythm disturbance;
• hidden — in the standard study of the ECG changes are not detected.

The relationship of the syndrome to sudden death

Retrospective study ECG signs in patients undergoing sudden cardiac arrest, demonstrated an interesting connection:

• half of the patients Express the excitability of the ventricles appeared after recovery of heart rate;
• among all patients with the syndrome of premature excitability the rate of sudden deaths is up to 0.6% annually.

To the high risk of fatal cases of combination with:

• tachycardia in history;
• defect Ebstein's;
• installed multiple version of anomalous transmission pulse;
• shortening of R-R interval on ECG.

The complaints of the patients is caused not by the presence of the syndrome of predposlednij, and combined with rhythm disorders. Up to 60% of patients note:

• bouts of palpitations;
• shortness of breath;
• a sense of fear in the background of discomfort in the chest;
• dizziness.

Such factors are not associated with the manifestation of the syndrome:

• old age;
• male;
• hypercholesterolemia.

What is considered the criteria of the syndrome?

Any typical manifestations in the form of complaints or impaired health syndrome causes. The world Health Organization in its recommendations, even offering to call syndrome without other manifestations of the phenomenon of predposlednij", and in the presence of clinical symptoms and ECG changes — syndrome predposlednij".

It is important that electrophysiological early appearance of the pulse precedes or accompanies complex tachyarrhythmias (atrial, group extrasystoles, supraventricular forms).