As a medical professional with expertise in cardiology, I can explain the significance of the T wave in an electrocardiogram (ECG). The T wave represents the repolarization, or recovery, phase of the ventricles after they have been depolarized during a heartbeat. This phase is crucial as it prepares the ventricles for the next contraction. The T wave's appearance can provide important information about the heart's electrical activity and can be indicative of various cardiac conditions. The interval from the beginning of the QRS complex to the apex of the T wave is known as the absolute refractory period. This period is when the heart muscle is unable to respond to any stimulus, ensuring that the heart beats in a coordinated and rhythmic manner. It's important to note that while a positive T wave is typical in most leads of a standard 12-lead ECG, a negative T wave is considered normal in lead aVR, which is one of the right chest leads. This is due to the direction of electrical current flow relative to the orientation of lead aVR. read more >>

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. ... However, a negative T wave is normal in lead aVR.read more >>