The pain inside the left side of the chest may need to consider coronary angina, acute myocardial infarction, pleurisy, breast disease and other conditions. The left side of the chest contains a wide range of internal, there are women’s left breast, as well as the thoracic cavity of the heart, lungs, pleura, intercostal nerves, the pancreas under the thorax and other organs, any part of the problem, may stimulate the local sensory nerve fibers, the emergence of pain sensation. Pain within the left side of the chest needs to be considered whether there are lesions of the above organs, so cardiac ultrasound, breast ultrasound, chest CT, electrocardiogram, heart infarction two, etc., to identify the presence of inflammation of the mammary glands, breast hyperplasia, mammary cysts, coronary angina pectoris, acute myocardial infarction, pleurisy, intercostal neuritis and other diseases. The consequences of coronary angina and acute myocardial infarction are more serious and may even lead to sudden death. The nature of the pain caused by different diseases, the specific location, the duration of the pain, etc., are different, so you need a professional doctor to assess the relevant examination before finally making a correct diagnosis. It is recommended to seek medical attention as soon as possible in case of pain in the left side of the chest to prevent untoward consequences.