Sleeping with the hand on the heart usually does not do anything, some people with poor cardiopulmonary function or poor rest may have nightmares, which can cause breathing difficulties. 1. Nightmares: hand on the heart and is lying on the back of the sleeping position, easy to affect the normal blood circulation of the heart transported to the whole body, thus affecting the metabolism of the whole body and the supply of oxygen, the majority of people will have nightmares, will dream that the body can not move, the chest has a sense of compression. 2. Difficulty in breathing: Sleeping with your hand on your heart will affect the function of your lungs, affecting your breathing and leading to dyspnea. If only once in a while, there is no great impact on health, do not need to worry too much, pay attention to change the sleeping position can be. If you sleep with your hand on your heart often have difficulty breathing, you need to go to the hospital in time to avoid aggravation of the condition.