How might hyperkalemia be reflected on an ECG?

Hyperkalemia, which refers to elevated levels of potassium in the blood, has distinct characteristics on an electrocardiogram (ECG). The most notable changes that occur as hyperkalemia progresses include peaked T waves and a widening of the QRS complex.

The presence of peaked T waves is one of the earliest signs of hyperkalemia, as increased potassium levels influence the repolarization phase of the cardiac action potential. As hyperkalemia worsens, the QRS complex may begin to widen due to further effects on myocardial conduction, reflecting the slowing of electrical impulses through the ventricles. This is particularly dangerous as it can lead to more serious arrhythmias or even cardiac arrest if not addressed.

The other choices do not accurately represent the changes seen in hyperkalemia. For example, normal QRS complexes would indicate healthy conduction with no electrolyte imbalance, flat T waves could suggest other conditions like ischemia rather than hyperkalemia, and a shortened QT interval does not correlate with high potassium levels. Understanding these specific ECG changes is crucial for recognizing hyperkalemia and managing it effectively.