What could be a potential complication of untreated hyperkalemia?

Untreated hyperkalemia can lead to serious complications, one of which is ventricular fibrillation. Hyperkalemia, characterized by elevated potassium levels in the blood, can significantly affect cardiac function. High potassium levels can alter the normal depolarization and repolarization processes in the heart, which can result in various arrhythmias.

Ventricular fibrillation is particularly dangerous as it represents a chaotic electrical activity in the ventricles, resulting in a lack of effective heart contractions and leading to sudden cardiac arrest if not treated immediately. The risk of developing ventricular fibrillation increases with higher potassium concentrations because it can disrupt the membrane potential of cardiac cells, making them more excitable and prone to erratic firing.

In contrast, while exercise intolerance, increased heart rate, and decreased blood pressure can be associated with various cardiac conditions, they are not direct causes or typical acute outcomes of untreated hyperkalemia in the same manner as ventricular fibrillation.