There are many reasons for sudden heartbeat acceleration, the common reasons are: first, physiological normal reaction, during high intensity physical activity, emotional excitement, shock, poor rest, menopause, etc., can feel sudden heartbeat acceleration, can be relieved after rest, in most cases, no special treatment is needed. Secondly, pathological accelerated heartbeat, mostly seen in high fever, more serious anemia, more serious infection, more serious lack of oxygen, abnormal thyroid function, etc., can also lead to a sudden feeling of accelerated heartbeat. Heart disease, common causes are atrial fibrillation, premature ventricular beats, supraventricular tachycardia, etc., the appearance of a sudden accelerated heartbeat, you need to go to the hospital in a timely manner for an electrocardiogram examination, which can clarify the cause of the disease and help to develop a treatment plan.