What is the T wave?

As a domain expert in cardiology, I can explain the T wave on an electrocardiogram (ECG). The T wave is a part of the electrical activity of the heart that is represented on an ECG. It follows the Q wave and precedes the P wave in the ECG cycle. The T wave represents the repolarization, or the return to the resting state, of the ventricular muscle fibers after they have been depolarized during the contraction phase. This recharging phase is crucial for the heart's ability to contract again in a regular rhythm. In a healthy ECG, the T wave is typically upright, indicating that the ventricles are repolarizing in a coordinated manner. Abnormalities in the T wave, such as inversion, flattening, or increased amplitude, can be indicative of various cardiac conditions, including ischemia, electrolyte imbalances, or certain drug effects. It's important to note that the T wave can be affected by factors other than cardiac issues, such as exercise, position of the body, or even the use of certain medications. Therefore, interpreting T wave changes requires a comprehensive understanding of the patient's medical history and current health status.

In electrocardiography, the T wave represents the repolarization, or recovery, of the ventricles. The interval from the beginning of the QRS complex to the apex of the T wave is referred to as the absolute refractory period. ... In most leads, the T wave is positive.