Atrial extrasystole

Atrial Extrasystole – Extrasystole, due to the premature occurrence of excitation in the focus of heterotopic automatism, located in one of the atria. Frequent atrial extrasystoles may be harbingers of atrial fibrillation or atrial paroxysmal tachycardia, accompanying overload or changes in the atrial myocardium.

ECG identification.

• • There are no changes in the P wave during an extraordinary contraction, the QRS complex is not changed, the compensatory pause is incomplete.
  • The P wave may overlap the previous T wave.
  • Features of extrasystoles depending on the place of occurrence
  • Extrasystoles from the left atrium are recognized by a negative P wave in standard ECG leads.

 

and chest leads V5_6

• • Extrasystoles from the lower and middle parts of the right atrium are recorded with a negative P’ wave in leads I, III, aVF, but positive P’ in standard lead I.
  • In 10-15% of cases, atrial extrasystole is accompanied by a functional impairment of conduction in the legs of the Huis bundle and a deformed QRS complex. Differential Diagnosis
  • Lower atrial extrasystoles will need to be differentiated from atrioventricular extrasystoles with previous atrial excitation (see Extrasystole from the atrioventricular node)
  • Usually mimics sinus arrhythmia. A distinctive feature is the constancy of the adhesion interval (distance P-P ‘). The differentiated strengthened electrocardiography is more informative.

 

Treatment:

• • Disopyramide 200-300 mg/day orally.
  • In ischemic heart disease, hyperthyroid states, verapamil 240–480 mg/day in 3–4 doses (risk of pharmacokinetic interaction in digitalized patients) or diltiazem 270–360 mg/day orally (cautiously with variant angina pectoris due to the risk of asystole) can be prescribed.
  • Bradycardia significantly complicates the treatment of supraventricular extrasystole, in these cases, the use of anticholinergics (belloid, bellataminal) is indicated. Contraindications
  • Disopyramide nbsp; – with heart block, severe uncompensated heart failure, weakness of the sinus node, glaucoma, urinary retention
  • Verapamil and diltiazem – for arterial hypotension, severe bradycardia, II-II degree heart block, sinoatrial blockade, sick sinoatrial node syndrome, uncompensated heart failure, severe liver and kidney dysfunction. drug interaction
  • Disopyramide interacts with B-blockers, alcohol, diuretics, liver enzyme inducers, anticholinergics, anticoagulants, antidiabetic drugs and does not affect the concentration of digoxin in the blood.
  • Disopyramide should not be administered within 48 hours before and after the end of the use of verapamil
  • Do not combine verapamil and diltiazem with quinidine
  • Verapamil and diltiazem increase the concentration of digoxin in the blood, enhance the effect of antihypertensive drugs
  • The effect of verapamil and diltiazem is potentiated by digoxin, propranolol (also increases the risk of atrioventricular conduction disturbances)
  • Rifampicin completely reduces the bioavailability of verapamil and diltiazem taken orally.

 

Synonym. Extrasystole supraventricular

 

See also Extrasystole

ICD. 149.1 Premature atrial depolarization