Which ECG change is typically seen in hyperkalemia?

Hyperkalemia, which refers to elevated levels of potassium in the blood, has specific effects on the electrocardiogram (ECG) that can aid in its identification. One of the hallmark changes associated with hyperkalemia is the presence of spiked T waves. This change occurs due to the influence of high potassium levels on the ventricular repolarization phase of cardiac electrical activity.

Potassium plays a critical role in the cardiac action potential, particularly during repolarization. When potassium levels rise, it leads to a more rapid repolarization of the cardiac myocytes. This accelerated repolarization manifests as T waves that become tall, narrow, and peaked—commonly referred to as "spiked" T waves. These changes can be seen in the precordial leads on the ECG and serve as a key indicator for clinicians to consider hyperkalemia as a potential diagnosis.

Other possible ECG changes associated with hyperkalemia include the widening of the QRS complex and the eventual risk of developing more severe arrhythmias as potassium levels continue to rise, but the distinctive spiked T waves are often one of the earliest and most recognizable signs.

Understanding that spiked T waves are characteristic of hyperkalemia helps clinicians quickly assess and manage this electrolyte