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. Patients with apical hyperacusis should eat foods rich in vitamin B, vitamin C, calcium and phosphorus, fresh vegetables and fruits, and a diet high in protein, vitamins, nutrients and easy to digest. The following foods are recommended to eat in moderation: 1, walnuts Walnuts contain the vast majority of oil is unsaturated fat, appropriate to eat some for the health of the body is not harmful. Can be eaten alone 1-2 per day, can also be placed in the porridge or added to other foods to eat. 2, tofu can reduce LDL (bad) cholesterol levels, thereby reducing the risk of cardiovascular disease. It is recommended to be consumed every morning. 3, fruit Contains a large amount of antioxidants, a substance that can prevent and control atherosclerosis of the heart as well as reduce the level of (bad) cholesterol LDL in the blood, thus reducing the risk of heart disease. It is recommended to take one per day, between meals.