The 7- to 10-day risk period for myocardial infarction includes papillary muscle dysfunction or rupture, cardiac rupture, embolism, ventricular aneurysm, and post-myocardial infarction syndrome, which varies from person to person. 1. Papillary muscle dysfunction or rupture: mitral valve papillary muscle closure is incomplete due to ischemia and necrosis. The total incidence is high, and the patients can recover by themselves in mild cases; in severe cases, it is seen in acute myocardial tissue infarction in the lower wall, rupture of papillary muscle structure occurs, left heart failure, severe acute pulmonary edema occurs, and it is easy to die. 2. Cardiac rupture: clinically rare, mainly manifested as ventricular free wall rupture, resulting in pericardial effusion caused by sudden death of acute cardiac tamponade, which may lead to ventricular septal rupture, heart failure and shock, and death within a few days. 3. Embolism: Because of the dislodgement of thrombus from the left ventricular appendage, embolism occurs in the arteries of the brain, kidneys, spleen, and other arteries. Because of the dislodgement of venous thrombus, it produces severe pulmonary embolism, and large pulmonary embolism can lead to the occurrence of sudden death. 4. Ventricular wall tumor, mainly seen in the left ventricle. Physical examination shows an enlarged left ventricular mural tumor. Abnormal pulsations in the ventricular region can be seen on echocardiography. Ventricular wall tumors can cause the development of heart failure and ventricular arrhythmias. 5. Post-myocardial infarction syndrome: It mostly occurs a few weeks to months after myocardial infarction, and can be recurrent, manifesting itself as pericarditis or pneumonia, etc. It is mainly characterized by symptoms such as fever and chest pain. It may be an allergic reaction of the body to the necrotic tissue. Patients are advised to take active treatment and consult a medical professional promptly if they feel unwell.