Correct the misrepresentation of the question, there is no such thing as a dichotomous rate, the correct formulation is cardiac dichotomous rhythm. The presentation is dangerous. Cardiac dysthymia is common atrial premature dysthymia and ventricular premature dysthymia, the degree of risk is not the same, atrial premature dysthymia does not affect hemodynamics, manifested as palpitations, panic, ventricular premature dysthymia is relatively higher degree of risk, if it is simple ventricular premature dysthymia is not accompanied by organic heart disease or short bursts of ventricular tachycardia, the risk is not great; but if there is organic heart disease or accompanied by ventricular tachycardia, there will be a certain degree of risk. Malignant arrhythmias such as sustained ventricular tachycardia and ventricular fibrillation may occur, significantly affecting hemodynamics and resulting in patients who, in addition to symptoms of palpitations, can experience chest pain, chest tightness, unstable blood pressure, dizziness, fainting, and can seriously lead to sudden cardiac death. The most common diseases in patients with dysthymia are coronary artery disease, dilated cardiomyopathy, heart valve disease, and, rarely, hereditary arrhythmias. The occurrence of dysthymia should be combined with medical history, as soon as possible to improve the electrocardiogram and cardiac ultrasound examination, the older it is necessary to do non-invasive coronary artery CTA or invasive coronary angiography.