Conduction: Difference between revisions

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==The QT interval==
==The QT interval==
[[File:Tangent QT.png|thumb|400px| The QT interval starts at the onset of the Q wave and ends where the tangent line for the steepest part of the T wave intersects with the baseline of the ECG. ]]
[[File:Tangent QT.png|thumb|400px| The QT interval starts at the onset of the Q wave and ends where the tangent line for the steepest part of the T wave intersects with the baseline of the ECG. ]]
[[File:QTeyeballing.jpg|thumb|400px|The eyeballing method to estimate QT prolongation. If the QT interval ends before the imaginary boundary halfway two QRS complexes, the QTc is probably normal. If the QTc reaches beyond the halfway line, the QTc is probably prolonged. This method is only 'valid' in registrations with normal (60-100/min) heart rates.]]
[[File:QTeyeballing.png|thumb|400px|The eyeballing method to estimate QT prolongation. If the QT interval ends before the imaginary boundary halfway two QRS complexes, the QTc is probably normal. If the QTc reaches beyond the halfway line, the QTc is probably prolonged. This method is only 'valid' in registrations with normal (60-100/min) heart rates.]]
'''The normal QTc (corrected) interval'''
'''The normal QTc (corrected) interval'''
The QT interval indicates how fast the ventricles are repolarized, becoming ready for a new cycle.
The QT interval indicates how fast the ventricles are repolarized, becoming ready for a new cycle.