Influenza A is a type of upper respiratory infection caused by the H1N1 influenza virus, characterized by high contagiosity. Typically, when the respiratory tract is infected with the Influenza A virus, it causes patients to develop fever, often high fever, along with headaches, dizziness, nasal congestion, runny nose, and sneezing. Moreover, some patients may have pre-existing asthmatic conditions, and infection with the Influenza A virus at this time can trigger asthma attacks, leading to various degrees of chest tightness. Many patients may also have cardiovascular diseases. When infected with the H1N1 influenza virus, the clinical symptoms caused during the acute phase can exacerbate the chest tightness and shortness of breath from some chronic cardiac changes. Therefore, if patients with Influenza A virus infection experience high fever, it may lead to increased heart rate, myocardial hypoxia, and a reduced oxygenation capacity, potentially causing varying levels of chest tightness. By making distinctions, one can identify the cause of the chest tightness.