Ventricular extrasystoles

Ventricular extrasystoles (ventricular premature contractions, VES) arise as a result of the presence of an ectopic focus in the cardiac conduction system distal to the bifurcation of the bundle of His or in the ventricular myocardium. VES can also occur in healthy individuals.

Clinical symptoms
VES are often asymptomatic. If they manifest clinically, it is mostly palpitations. Accumulation of VES can result in syncope or chest pain.

Diagnostics
Diagnosis is based on EKG. We observe the following changes on the ECG:
 * The QRS complex comes prematurely, it is not preceded by a P wave (in the case of retrograde conduction of the impulse AV node the P wave can be located after the QRS complex) ;
 * The QRS complex is abnormal (different in shape from the QRS complex originating from the SA node; it is wide - lasts longer than 120 ms);
 * The QRS complex is followed by a complete compensatory pause (R-RVES before VES and RVES-R after VES is equal to twice R-R interval sinus rhythm);
 * The T wave is large, usually discordant to the QRS complex.
 * If there is one ectopic focus in the myocardium, the extrasystoles originating from it have the same shape and are referred to as monotopic.
 * If there are multiple ectopic foci in the myocardium generating premature excitations, the extrasystoles have a different shape and are called polytopic.

A more frequent occurrence of KES should lead to a more detailed cardiology examination. We are looking for organic heart disease and left ventricular dysfunction (echocardiography, Holter monitoring, stress EKG, electrophysiological examination).

Classification


The "Lown classification" is still used to classify VES today.
 * {| class="wikitable"

! !! Classification of VES according to Lown ! Degree !! VES type
 * 0 || no VES
 * 1a || isolated, sporadic, monomorphic VES, < 1/min. and < 30/hour
 * 1b || isolated, sporadic, monomorphic VES, > 1/min., but < 30/hr
 * 2 || isolated, frequent, monomorphic VES > 30/hr
 * 3a' || isolated, polymorphic VES
 * 3b || bigeminically bound mono- or polymorphic VES
 * 4a || VES in pairs (couplets)
 * 4b || VES in bursts ie 3 or more consecutive VES
 * 5 || early VES ("R on T" phenomenon)
 * colspan=2 | VES 3-5 are referred to as "complex forms of VES"
 * }
 * 3b || bigeminically bound mono- or polymorphic VES
 * 4a || VES in pairs (couplets)
 * 4b || VES in bursts ie 3 or more consecutive VES
 * 5 || early VES ("R on T" phenomenon)
 * colspan=2 | VES 3-5 are referred to as "complex forms of VES"
 * }
 * 5 || early VES ("R on T" phenomenon)
 * colspan=2 | VES 3-5 are referred to as "complex forms of VES"
 * }
 * }


 * Couplet (pair) – 2 extrasystoles coming in a row.
 * Nonsustained ventricular tachycardia (salvo, triplet) – 3 extrasystoles in a row.
 * Bigeminia - each supraventricular contraction is followed by 1 ES.
 * Trigeminy - every 2 supraventricular contractions are followed by 1 ES.

Treatment
Treatment for VES includes:
 * antiarrhythmics group I–III (β-blockers, sotalol, propafenone; the possible proarrhythmogenic effect of antiarrhythmics must also be kept in mind);
 * catheter radiofrequency ablation of ectopic focus;
 * VES triggering ventricular tachycardia runs can be treated by implanting a defibrillator.

Related Articles

 * Extrasystole
 * Flutter halls
 * Ventricular fibrillation
 * Antiarrhythmics

Used literature

 * HOLAJ, Robert. Cardiological group. III. internal clinic VFN a 1. LF UK in Prague, 2009.
 * VILIKUS, Zdeněk. Interpretation of EKG at rest and during exercise. Institute of Physical Education Medicine 1. LF UK and VFN; 2010.
 * HOLAJ, Robert. Cardiological group. III. internal clinic VFN a 1. LF UK in Prague, 2009.
 * VILIKUS, Zdeněk. Interpretation of EKG at rest and during exercise. Institute of Physical Education Medicine 1. LF UK and VFN; 2010.