T wave inversion
Also calledTWI · inverted T waves · T-wave inversion · T wave inversions
Definition
A T wave whose main deflection is negative (below the baseline). In adults the T wave is normally upright in I, II and V3 to V6 and inverted in aVR, and it may be upright or inverted in III, aVL and V1; in adolescents and young adults it may also be inverted in V2 and slightly inverted in aVF. In ischemia it reflects abnormal ventricular repolarization, and deep, symmetrically inverted T waves strongly suggest ischemia. The Fourth Universal Definition counts T-wave inversion of more than 1 mm (0.1 mV) in two contiguous leads with a prominent R wave or an R/S ratio above 1 as an ischemic change. T-wave inversion also has many nonischemic causes, such as ventricular hypertrophy, bundle branch block and pacing.
Sources
- Thygesen K, Alpert JS, Jaffe AS, et al. Fourth universal definition of myocardial infarction (2018). Circulation. 2018;138(20):e618-e651. doi.org/10.1161/CIR.0000000000000617
- Channer K, Morris F. ABC of clinical electrocardiography: myocardial ischaemia. BMJ. 2002;324(7344):1023-1026. doi.org/10.1136/bmj.324.7344.1023
- Rautaharju PM, Surawicz B, Gettes LS. AHA/ACCF/HRS recommendations for the standardization and interpretation of the electrocardiogram: part IV: the ST segment, T and U waves, and the QT interval. Circulation. 2009;119(10):e241-e250. doi.org/10.1161/CIRCULATIONAHA.108.191096
Last reviewed 2 October 2026. Every definition in the EKG Dictionary cites the guideline, consensus statement or original paper it comes from.