The first heart sound occurs at the beginning of cardiac systole and is low in pitch and long in duration (about 0.15 seconds). The causes include the contraction of the ventricular muscle, the sudden closure of the atrioventricular valve and the subsequent ejection of blood into the aorta, among other vibrations. The best place to hear the first heart sound is at the fifth intercostal space in the midclavicular line or at the right border of the sternum. Prevention of hyperacusis of the apical 1st heart sound: 1. Diet: Pay attention to strengthening nutrition after surgery, not to eat too salty food, mainly to supplement protein and various vitamins. Patients taking warfarin anticoagulation should not consume too much or long-term foods rich in vitamin K, such as spinach, pork liver, carrots, cauliflower, peas, etc. As drinking alcohol can affect the metabolism of warfarin, so do not drink alcohol during anticoagulation. 2, lifestyle habits: pay attention to maintain good habits, less late at night, avoid strain. 3, prevention of infection: usually can be appropriate exercise to enhance physical fitness, to prevent colds and other respiratory inflammation, if suffering from periodontitis, broken, urinary tract infections, etc.. You should seek medical attention promptly and take the initiative to explain to the doctor that you have undergone heart valve surgery and provide accurate information about your current medication. 4. Seek medical advice: Once you are not feeling well, you should use medication under the guidance of a doctor and not use cold medicine and antibiotics and other drugs at your own discretion.