Not all people can feel their heartbeat. Women, because of their breasts, and people who are obese and many others cannot feel their heartbeat. Some people who are thin may be able to feel it. Diseases such as pericardial effusion may also make it difficult to feel the heartbeat. People who are affected by breasts, or who are fat, or who have strong muscles may not be able to feel their heartbeat. People who are thin are more likely to be able to feel the heartbeat because the chest wall is thinner. Some diseases, such as pericardial effusion, when there is more fluid in the pericardium, the heartbeat cannot be felt. There is also heart failure when the heart muscle contraction is weak, or emphysema, because of the impact of the chest cavity, these can lead to not feel the heartbeat. If there is an abnormality in the heart, it is important to go to the hospital in time to clarify whether a disease has occurred and to treat it promptly.