QT interval

 Q: The QT interval on EKG is measured from? (select one)

A) start of the QRS complex 

 B) end of the QRS complex 

Answer: A

There are two mistakes usually made while looking into QT interval on EKG. 

1. QT interval should be measured from the beginning of the QRS complex (instead of the end) to the end of the T-wave. It needs to be corrected for the heart rate.

2. If U wave is present it should not be included in the QT interval.

#cardiology

Reference:

Postema PG, Wilde AA. The measurement of the QT interval. Curr Cardiol Rev. 2014;10(3):287-294. doi:10.2174/1573403x10666140514103612