QRS-T Angle Index Calculator

QRS-T Angle Index: Explanation and Clinical Context The QRS-T angle represents the spatial difference between the depolarization (QRS) and repolarization (T wave) vectors of the heart on a 12-lead ECG. A wider QRS-T angle is associated with abnormal ventricular repolarization and is a strong predictor of adverse cardiovascular events, including sudden cardiac death and all-cause mortality. Normal values are usually <45°, intermediate risk is 45–90°, and high risk is >90°.

The QRS-T angle adds incremental prognostic value over traditional risk factors and can be calculated using frontal plane axes from a standard 12-lead ECG.