Reply to Letter to the Editor: "Clinical Value of Tp-e/QTc Ratio in Patients Undergoing Coronary Angiography for Acute Coronary Syndrome".

To the Editor,

We read the letter about our manuscript. We thank the author for the interesting comments.[1] First, we could not evaluate the relationship between ventricular arrhythmias and Tp-e interval and Tp-e/QT ratio, and this limitation was highlighted in our study.[2] Tp-e interval was defined as the interval between the peak and the end of the T wave. QTc dispersion (QTcD) was determined as the difference between the maximum and minimum QTc interval in different leads. Tp-e was measured using 2 methods. The first method is the “Tangent Method.” In this method, the time in milliseconds from the peak of the T wave (or nadir if negative or biphasic T wave) and the intersection between the tangent at the steepest point of the T-wave downslope and the isoelectric line was calculated. The second method is the “Tail Method.” The time from the peak or nadir of the T wave to the point where the wave reached the isoelectric line was calculated.[3-5] We used the end of the T wave as the point where the T wave returned to the isoelectric baseline (Tail Method). The Tp-e interval was obtained from the peak of the T-wave to the end of the T-wave in ST-segment elevated leads. In the case of negative T waves, we evaluated and calculated the Tp-e interval as a mirror image.