Extrasystole ventricular

ventricular

Ventricular extrasystole – premature excitation and contraction of the ventricles, caused by a heterotopic focus of automatism in the myocardium of one of them. Ventricular extrasystole is based on the mechanisms of re-entry and post-depolarization in the ectopic foci of the branches of the Huis bundle and Purkinje fibers. Etiology. Physical and mental stress, drug intoxication (cardiac glycosides, aminophylline, TAD, B-agonists [isoproterenol] or dopamine, caffeine, nicotine), electrolyte imbalance (especially hypokalemia).

ECG identification

• • The QRS complex is widened and deformed, duration >0.12 s.
  • The shortened ST segment and the T wave are discordant to the main wave of the QRS complex.
  • Complete compensatory pause.
  • The localization of the ectopic focus is determined by the shape of the extrasystoles in the chest leads V,_2 and V5_6.
  • Left ventricular extrasystoles – a picture of a complete blockade of the right leg of the Hayes bundle (see. Intraventricular blockade)
  • QRS complex widening >0.12 s in all leads
  • Deformation of the QRS complex with the appearance of notches and an increase in the time of internal deflection in the right chest leads
  • An increase in the amplitude of the QRS complex teeth in the right chest leads
  • Discordant deviation of the ST segment and T wave in the right chest leads
  • EOS deviation to the right (optional).
  • Right ventricular extrasystoles – a picture of a complete blockade of the left leg of the Hayes bundle (see. Intraventricular blockade)
  • Broadening of the QRS complex> 0.12 s in all leads
  • Deformation of the QRS complex with the appearance of notches and an increase in the time of internal deflection in the left chest leads
  • An increase in the amplitude of the QRS complex teeth in the left chest leads
  • Discordant deviation of the ST segment and T wave in the left chest leads
  • EOS deviation to the left (optional).

Treatment

• • Treatment of the underlying disease.
  • Indications for drug therapy – see Extrasystole.
  • Preparations containing potassium (potassium chloride, panangin, asparkam) – with hypokalemia, incl. caused by digitalis products.
  • In MI – lidocaine 400-600 mg / m or 50-100 mg / in a bolus for 3-4 minutes with continued drip infusion at a rate of 1-4 mg / min, against which, 5 minutes after the first bolus, you can give another bolus of the same or half the dose. Contraindicated in AV block II-II1 degrees, hypersensitivity, Wolff-Parkinson-White syndrome, sick sinus syndrome.
  • Propranolol (anaprilin) ​​10-30 mg 3-4 r / day.
  • In some cases, procainamide orally, e / m or / in, disopyramide, propafenone or sotalol 80 mg 2 r / day (up to 240-320 mg / day). Sotalol should be discontinued gradually due to the risk of withdrawal; the product interacts with other antiarrhythmic, hypoglycemic products, clonidine, reserpine, TAD.
  • Amiodarone 800-1600 mg/day for 1-3 weeks until the effect is achieved, the maintenance dose is traditionally 400 mg/day.
  • Antiarrhythmic drugs of class I with long-term use increase mortality.

See also Intraventricular blockade, Extrasystole of the ICD. 149.3 Premature ventricular depolarization