What is QRST Angle?

In the frontal plane, QRST angle is the between the QRS vector and the ST- T wave vector. QRST angle is less than 90 degrees in females and less than 107 degrees in males. Corresponding to this there is a spatial QRST angle in three dimensions, which will be a solid angle. Many of the modern computerized electrocardiograms display a clock face showing the vectors of P, QRS and T waves. In the illustration, P and QRS vectors are at 20 degrees and the T vector is at 10 degrees. That is why P and QRS vectors are superimposed on each other. QRST angle is 10 degrees in this normal ECG. QRST angle widens in the presence of ischemia and hypertrophy, accounting for ST-T becoming discordant to the QRS complex.