Define the term "hyperkalemia" and its effect on the heart.

The term "hyperkalemia" refers to elevated levels of potassium in the blood. Potassium plays a crucial role in maintaining normal electrical activity in the heart, influencing both the generation and conduction of electrical impulses. When potassium levels rise significantly, it can disrupt the heart's electrical stability, leading to various types of arrhythmias.

In severe cases, hyperkalemia can cause life-threatening conditions such as ventricular fibrillation or asystole, where the heart either quivers ineffectively or stops beating altogether. The clinical manifestations associated with hyperkalemia often include changes on the electrocardiogram (ECG), such as peaked T-waves, widening of the QRS complex, and possible loss of the P wave, which indicate a high risk for arrhythmias.

Understanding hyperkalemia is essential for healthcare providers, especially when monitoring patients on medications that may affect potassium levels, such as diuretics or ACE inhibitors. Prompt recognition and management of this condition can be critical in preventing serious cardiac complications.