At noon feel panic heartbeat fast both physiological factors, there are disease factors, physiological factors can be seen in the exercise, nervousness, etc., disease factors are seen in arrhythmia, hyperthyroidism, heart failure, etc.. 1. Physiological factors: exercise, mental stress will enter a relatively high metabolic state, sympathetic nerve excitation, resulting in rapid heartbeat, this situation is often in a few minutes after the improvement of their own, belonging to the normal physiological response. 2. Disease factors: (1) arrhythmia: such as atrial fibrillation, paroxysmal supraventricular tachycardia, etc., can cause sudden heart rate, if the tachycardia lasts for a long time, it is best to go to the hospital to check the 24-hour electrocardiogram, to see if there are arrhythmic diseases. (2) Hyperthyroidism: When the thyroid gland is hyperfunctional, the level of thyroid hormone in the body increases, and the body shows high metabolism, and the heartbeat will increase. For this kind of patients should actively treat the primary disease, in order to reduce or avoid the symptoms of fast heartbeat and panic after waking up. (3) Heart failure: In chronic heart failure, the heart output decreases, and the tissues and organs will have different degrees of insufficient perfusion, so the symptoms of fast heartbeat and panic attack will appear reflexively. The causes of panic and fast heartbeat are very complex, and it is recommended to seek timely medical treatment and systematic treatment under the guidance of a doctor.