First, it is important to improve the understanding of arrhythmia treatment, which arrhythmias should be treated and which arrhythmias do not necessarily need to be treated. For life-threatening arrhythmias, the main consideration in drug selection is effectiveness; for treatment of arrhythmias that improve symptoms, the main consideration is the safety of the drug. Therefore, the emphasis in treatment is on the consequences produced by the treatment rather than on the treatment of the arrhythmia itself. In the treatment of arrhythmias, more emphasis is placed on treating the cause of the arrhythmia and improving the substrate that produces the arrhythmia, such as focusing on improving myocardial ischemia, correcting cardiac function, and improving hemodynamic abnormalities, than on treating the arrhythmia itself.