Extrasystole

From WikiLectures

Extrasystole (premature contraction, premature depolarization, premature contraction) is an excitation arising prematurely outside the SA node. Such an excitation occurs before the excitation in the SA node, it precedes the excitation from the SA node and thus prematurely depolarizes the cardiac myocardium. The excitation from the SA node is not applied because it comes at a time when the myocardium is already in the refractory phase after the previous depolarization by the premature excitation.

Atrial extrasystoles:


Ventricular extrasystoles:


Etiopathogenesis[edit | edit source]

File:KES.JPG
Ventricular extrasystole

Pathogenetically, extrasystoles arise on the basis of "ectopy" or "reentry mechanism", the basis of which can be:

Types[edit | edit source]

According to the place where the premature excitation occurs, we distinguish 3 types of extrasystoles:

  1. atrial extrasystoles;
  2. junctional extrasystoles;
  3. ventricular extrasystoles.

Links[edit | edit source]

Related Articles[edit | edit source]

External links[edit | edit source]

References[edit | edit source]

  • HAMPTON, John R.  ECG Concise, Clear, Clear. 6th edition. Grada, 2005. 149 pp. ISBN 80-247-0960-0.
  • HAMAN, Peter. EKG Learning Website : EKG Basics [online]. [feeling. 2010-12-11]. < http://www.ekg.kvalitne.cz/tvorba.htm#Supraventrikul%C3%A1rn%C3%AD%20extrasystoly >.
  • HELLO, Robert. Cardiology ring. III. internal clinic of VFN and 1st Faculty of Medicine of the University of Prague in Prague, 2009.
  • VILIKUS, Zdeněk. Interpretation of ECG at rest and during exercise. Institute of Physical Education Medicine 1. LF UK and VFN; 2010.