Q-T interval

Q-T interval, the period from the beginning of the QRS complex to the end of the T wave on an electrocardiogram. It reflects the refractory period of the heart. A long Q-T interval is associated with the life-threatening ventricular tachycardia known as torsades de pointes. Quinidine, procainamide, and disopyramide can lengthen the Q-T interval.

Q-T interval (Wesley, 2012)