Hello,
If you are feeling pain in left side of chest or as you were saying pain in heart. It may have many causes like if the pain is related to heart then it might be due to
*Coronary artery disease where any artery of heart get blocked.
*Myocardial infarction(
heart attack). Here sometimes other accompanied symotoms are present like sweating, nausea or
shortness of breath etc. But presence of symptoms is not always necessary.
* Myocarditis where inflammation of heart muscles occur.
* Besides heart, any problem in lungs might also cause pain in left side of chest. Pleuritis(inflammation of lining of lungs), asthma, pneumonia,
pneumothorax might be other causes.
* Sometimes
hyperacidity also causes pain in heart or heart burning, esophageal
hypersensitivity or perforation might be other causes.
* Sometimes common causes like
muscle strain or rib problem due to excessive coughing or
rib fracture due to injury might also cause pain in left side of chest.
* These are the most common causes behind the chest pain on left side or heart pain as you said and these can be ruled out by doctor after clinical examination. So visit a nearby physician to know the exact cause. If you require any investigation you will also come to know about that too.As once diagnose is made it would be easier for you to get treatment.
* I hope you are satisfied with my answer.
Thank you.