Male left chest left upper hidden pain may be caused by myocardial infarction, arrhythmia, viral myocarditis, costochondritis and other diseases. 1. Myocardial infarction: it is because of coronary artery obstruction, so that the myocardium acute ischemia and necrosis, impaired function. Before the onset of the disease, there may be weakness, chest tightness, left chest pain and other manifestations, and during the attack, there may be crushing pain in the chest. 2. Arrhythmia: It is a cardiac syndrome in which the heart beats too fast, too slow or irregularly causing a series of clinical manifestations. In the early stage, there may be panic, breathlessness, dizziness, chest pain, dyspnea and other symptoms. 3. Viral myocarditis: it is the inflammation that occurs when the virus infects the myocardium and its tissues. Clinical manifestations are related to the severity of the lesion. In mild cases, there may be only vague chest pain and palpitation, while in severe cases, there may be a sense of cardiac arrest or even shock. 4. Costal chondritis: due to infection or other reasons can lead to costal chondritis, manifested as localized vague pain. There may be other reasons for the hidden pain on the left side of the male left chest, so it is recommended to go to the hospital in time to clarify the cause of the disease, and treat the cause of the disease. The reason for this is the fact that it is a very important part of the process.