The main effect of hyperkalemia on the body is a wide variety of arrhythmias, which can result in life-threatening cardiac arrest, ventricular fibrillation, and changes in the electrophysiological characteristics of the myocardium, as manifested by the electrocardiogram, i.e., the appearance of high pointed T waves, reduced amplitude of P and QRS waves, widened intervals, and deepened S waves. In severe hyperkalemia, the wide and deep S waves may be connected to the T waves behind in a positive genetic wave. Reduced cardiomyocyte autoregulation may lead to sinus bradycardia and sinus arrest. Reduced cardiomyocyte conduction may lead to conduction block, such as intra-atrial, atrioventricular and intraventricular block. Abnormal excitability of cardiac myocytes may be affected together, and folding excitation may occur, etc.