What ECG findings are indicative of hyperkalemia?

Hyperkalemia, or elevated potassium levels in the blood, leads to distinct changes on an electrocardiogram (ECG) due to its effects on cardiac myocyte depolarization and repolarization.

The characteristic ECG findings in hyperkalemia begin with the appearance of peaked T waves. These T waves become progressively taller and more pointed as potassium levels rise. This change is often the earliest indicator of hyperkalemia on the ECG. As the condition worsens, the QRS complex begins to widen. Widening of the QRS complex indicates that ventricular conduction is being affected, which can lead to dangerous arrhythmias.

In severe cases of hyperkalemia, further changes can occur, such as the merging of the QRS complex with the T wave (forming a sine wave pattern) and ultimately ventricular fibrillation or asystole if untreated.

This understanding of the ECG changes associated with hyperkalemia is crucial for effective diagnosis and management, as timely recognition can inform interventions to stabilize potassium levels and prevent potentially life-threatening cardiac complications. The other options listed correspond to different electrolyte imbalances or ECG changes that are not characteristic of hyperkalemia.