A sudden pounding of the heart is usually associated with premature beats, such as atrial or ventricular beats. Many people who are sensitive to premature beats have similar symptoms, and most normal people sometimes have them as well. In this case, if the episodes are infrequent, the type of premature beats can be temporarily observed or the ECG can be improved, depending on the frequency of the beats, if necessary. In case of frequent atrial and ventricular premature episodes, it may be necessary to look for the cause. Some structural changes in the heart can lead to atrial and ventricular premature episodes. If it is only occasional atrial or ventricular premature contractions, most of them do not need to be overly worried and should only be observed regularly. You should pay attention to adjusting your emotions, pay attention to your work and rest routine, and don’t overstress.