Conduction: Difference between revisions

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The ventricles depolarize  normally within 0.10 seconds. When this is longer than 0.12 seconds, this is a '''[[conduction delay| conduction delay (Left bundlebranchblock or Right bundlebranchblock]]'''.
The ventricles depolarize  normally within 0.10 seconds. When this is longer than 0.12 seconds, this is a '''[[conduction delay| conduction delay (Left bundlebranchblock or Right bundlebranchblock]]'''.


==The QT time==
==The QT interval==
  The QT time indicates how fast the ventricles are repolarized and how fast they are ready for a new heart cycle
  The QT interval indicates how fast the ventricles are repolarized and how fast they are ready for a new heart cycle


The normal value for QTc(orrected) is: 440ms for men and 450 ms for women.
The normal value for QTc(orrected) is: 440ms for men and 450 ms for women.
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The QT-interval comprises the QRS-complex, the ST-segment, and the T-wave.
The QT interval comprises the QRS-complex, the ST-segment, and the T-wave.


In  a (serious) prolonged QT time, is takes longer for the myocardial cells to be ready for a new cardiac cycle. There is a possibility that some cells are not yet repolarized, but that a new cardiac cycle is already initiated. These cells are at risk for uncontrolled depolarization and induce a [[Arrhythmias#Torsade_de_pointes|torsade de pointes]], a ventricular tachycardia.
In  a (serious) prolonged QT time, is takes longer for the myocardial cells to be ready for a new cardiac cycle. There is a possibility that some cells are not yet repolarized, but that a new cardiac cycle is already initiated. These cells are at risk for uncontrolled depolarization and induce a [[Arrhythmias#Torsade_de_pointes|torsade de pointes]], a ventricular tachycardia.