Difference between revisions of "Second-degree atrioventricular block type 2"

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[[en:Second-degree atrioventricular block type 2]]
 
[[en:Second-degree atrioventricular block type 2]]
 
[[ru:Атриовентрикулярная блокада II степени Мобитц 2]]
 
[[ru:Атриовентрикулярная блокада II степени Мобитц 2]]
Second-degree [[atrioventricular block]] type 2 may be transient and it occurs rare (only 10% of all cases of second-degree atrioventricular block). In contrast to [[second-degree atrioventricular block type 1]], this block is usually caused by conduction disorder lower trunk of [[bundle of His]] (on the background of the front myocardial infarction), associated with wide QRS complex, and often progresses to [[third-degree or complete atrioventricular block]]. In such cases, external transcutaneous pacing or transvenous pacing are usually carried out: electrode is placed in the heart, which helps to impose to the ventricles optimum heart rate (80-90 beats per minute).  
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Second-degree [[atrioventricular block]] type 2 may be transient and it occurs rare (only 10% of all cases of second-degree atrioventricular block). In contrast to [[second-degree atrioventricular block type 1]], this block is usually caused by conduction disorder lower of the trunk of [[bundle of His]] (on the background of the front myocardial infarction), associated with wide QRS complex, and often progresses to [[third-degree or complete atrioventricular block]]. In such cases, external transcutaneous pacing or transvenous pacing are usually carried out: electrode is placed in the heart, which helps to impose to the ventricles optimum heart rate (80-90 beats per minute).  
  
 
When second-degree atrioventricular block type 2 occurs, the P-R interval, preceding  the fallen contraction, is always constant. The P-R interval is not changed even after the contraction has fallen.  In the cases relevant to this last criterion, second-degree atrioventricular block type 2 is limited by Gis-[[Purkinje fibers|Purkinje]] system. The R-R interval in non-fallen contructions is usually normal, less often elongated. QRS complex is normal in 35% of patients and is wide in 65% of cases.
 
When second-degree atrioventricular block type 2 occurs, the P-R interval, preceding  the fallen contraction, is always constant. The P-R interval is not changed even after the contraction has fallen.  In the cases relevant to this last criterion, second-degree atrioventricular block type 2 is limited by Gis-[[Purkinje fibers|Purkinje]] system. The R-R interval in non-fallen contructions is usually normal, less often elongated. QRS complex is normal in 35% of patients and is wide in 65% of cases.

Revision as of 11:03, 25 March 2017

Second-degree atrioventricular block type 2 may be transient and it occurs rare (only 10% of all cases of second-degree atrioventricular block). In contrast to second-degree atrioventricular block type 1, this block is usually caused by conduction disorder lower of the trunk of bundle of His (on the background of the front myocardial infarction), associated with wide QRS complex, and often progresses to third-degree or complete atrioventricular block. In such cases, external transcutaneous pacing or transvenous pacing are usually carried out: electrode is placed in the heart, which helps to impose to the ventricles optimum heart rate (80-90 beats per minute).

When second-degree atrioventricular block type 2 occurs, the P-R interval, preceding the fallen contraction, is always constant. The P-R interval is not changed even after the contraction has fallen. In the cases relevant to this last criterion, second-degree atrioventricular block type 2 is limited by Gis-Purkinje system. The R-R interval in non-fallen contructions is usually normal, less often elongated. QRS complex is normal in 35% of patients and is wide in 65% of cases.