What does a flattened "T" wave in an ECG indicate?

A flattened "T" wave in an ECG is primarily indicative of hypokalemia, which is a condition characterized by low levels of potassium in the blood. Potassium plays a critical role in maintaining normal cardiac electrical activity, and when its levels drop, it affects the repolarization phase of the cardiac cycle, which is represented on the ECG by the T wave. In the case of hypokalemia, the T wave can become flattened or even inverted, providing a visual cue on the ECG that suggests the need for further evaluation and potential treatment of the potassium deficiency.

Monitoring electrolyte levels, especially potassium, is crucial for maintaining heart health, and recognizing abnormal ECG patterns can lead healthcare providers to investigate and address underlying issues. In contrast, other options like hyperkalemia typically present with peaked T waves, while normal electrolyte levels would not produce any significant changes in ECG waveform. Arrhythmias themselves can lead to various ECG changes but are not specifically indicated by a flattened T wave alone.