Why does long QT cause a tachyarrhythmia?

I don't understand why long QT cause a tachyarrhythmia (e.g. Torsades de pointes) when it is essentially a lengthening of the PQRST complex. Would you not expect to see a bradycardia?

Authored By Rachel Simton on Monday 29th October 2012

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Dr Michael Zhang
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Medical Student - Manchester
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Posted over 4 years ago

Hi Rachel:
I have put down what I understand down hopefully it will make sense to you:

  1. What is an ECG - it is electrical activity of the heart (N.B. it doesn't represent muscle contraction as such, just the electrical activity

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Alastair Burden
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Medical Student
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Posted over 4 years ago

From what I understand, it is an "R" on "T" situation. In that the R-wave (ventricular depolarisation) occurs at the same time as the T-wave (ventricular repolarisation). This is the same reason why it is important to give a synchro

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siteocean
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Posted 5 months ago
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