(Disclaimer: This article is for scientific purposes only. In order to protect the patient’s privacy, the relevant information in the following content has been processed) Abstract: A 41-year-old male patient reported that he had sudden shortness of breath and dyspnea, accompanied by edema of both lower limbs, one week ago after a physical labor. At that time, it was thought to be due to exertion and was not treated. However, after resting, the discomfort persisted and the patient came to the clinic. After a series of examinations, the patient was finally diagnosed with cardiac mucinous tumor. After aggressive surgical treatment with medication, the patient’s cardiac mucinous tumor was successfully removed, and the physical discomfort disappeared. Basic information] Male, 41 years old [Disease type] Mucinous tumor (cardiac mucinous tumor) [Hospital] The First Affiliated Hospital of China Medical University [Date of consultation] July 2021 [Treatment plan] Surgery (open chest surgery under cryogenic extracorporeal circulation) + intravenous drug treatment (intravenous injection of cefuroxime sodium) [Treatment cycle] In-hospital treatment for 14 days, with regular follow-ups [Results] Cardiac mucinous tumor was successfully removed, and the patient’s physical discomfort disappeared. Mucinous tumor successfully removed, somatic discomfort disappeared I. Initial consultation The patient, Mr. Wang, 41 years old, came to the clinic because of dyspnea and edema of both lower limbs. He reported that one week ago, after a physical labor, he had shortness of breath, dyspnea, breath-holding phenomenon, and edema of both lower limbs. At that time, he thought it was caused by exertion, so he did not take any medication, thinking that it would be improved after rest. However, after resting, the patient’s symptoms did not decrease, and the above symptoms still existed, and the original breath-holding after activity changed to breath-holding at rest. In the last week, the patient’s appetite was poor, accompanied by joint pain. The patient was asked about his past medical history and denied any history of chronic diseases such as heart disease or diabetes mellitus, and there was no history of allergy or major surgery. Physical examination of the patient showed an elevated temperature of 38.6°C. Chest X-ray was performed, which showed that the patient’s whole heart was enlarged and there was a dense shadow on the right side of the right thoracic cavity. Echocardiography was performed, and a moving cloud of light echoes could be seen. Laboratory tests were performed on the patient, which showed an increase in blood sedimentation and electrophoretic changes in serum proteins. Since the echocardiographic findings were typical, the patient was finally diagnosed with cardiac mucinous tumor and was admitted to the hospital. After the diagnosis was confirmed, the patient was told that the cardiac mucinous tumor should be surgically removed as soon as possible to restore cardiac function and effectively avoid the risk of tumor malignancy or sudden blockage of the atrioventricular valve orifice, which could lead to sudden death or embolism after the tumor debris was dislodged. After hearing this, the patient expressed understanding and agreed to undergo surgical treatment. After general anesthesia, hypothermic extracorporeal circulation was used to replace the patient’s heart and lungs during the operation. An incision was made in the middle of the patient’s sternum, and after opening the heart, the adherent part of the tumor was found and resected under direct vision, and part of the atrioventricular septal tissues attached to the tip were resected together, and the tissues around the intraoperative incision were then thoroughly rinsed with physiological saline, so as to prevent the tumor debris from dropping to other parts of the body, and the incision was finally sutured and closed. Finally, the incision was sutured, the abdomen was closed, and the patient was sent back to the ward promptly after he was awake. After the operation, the patient was injected with cefuroxime sodium intravenously to prevent postoperative secondary infection. On the first day after surgery, the patient’s body temperature was 36.8℃, heart rate was 79 beats/min, blood pressure was 80/110mmHg, vital signs were stable, and there was no large amount of blood oozing or pus flowing from the surgical incision site, which indicated that the surgery was more successful. On the 4th day of postoperative treatment, the patient reported that the symptoms of shortness of breath, dyspnea, cyanosis and fever had been reduced, the edema of both lower limbs had been significantly reduced, and the patient was in good mental state, with no nausea, vomiting and other adverse symptoms. On the 14th day of postoperative treatment, the symptoms of shortness of breath, dyspnea, cyanosis and fever disappeared, the body temperature was 36.6℃, the heart rate was 76 beats/min, the blood pressure was 79/117mmHg, and the echocardiographic examination showed no abnormality, the patient reached the criteria for discharge, and was discharged from the hospital, and was instructed to undergo regular rechecks. IV. Precautions The patient was very satisfied with the results of this treatment and was very happy when he was discharged from the hospital, and I felt very pleased in my heart. When discharged from the hospital, I advised the patient that he should keep his emotions stable, avoid too much excitement, and avoid doing heavy physical activities to prevent triggering or aggravating the disease. Eating more eggs, fish, melon, peaches, carrots, lettuce and other foods with high nutritional value and good digestion, and less spicy and greasy food can help maintain the immune system, which in turn promotes the health of the body and the improvement of the disease. In addition, I also advise patients that although their condition is under control, it is not yet cured, so they should consult a doctor on a regular basis to monitor the progress of their condition, and if they find any abnormal symptoms, they should consult a doctor immediately. When you find yourself with repeated shortness of breath and other uncomfortable symptoms, it is recommended that you consult a doctor in time to find out the cause, so as to avoid misdiagnosis. Like the male patient in this case, he had shortness of breath, dyspnea and other symptoms, and after systematic testing, he was found to have cardiac mucinous tumor, but fortunately, he was lucky to have found it in time, and therefore, after appropriate treatment, his condition has been effectively controlled, which alleviated the discomfort brought by the disease, and to a certain extent, improved the quality of life of the patient.