Q-T interval

n.
  1. The time elapsing from the beginning of the QRS complex to the end of the T wave in an electrocardiogram, representing the total duration of electrical activity of the ventricles.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.