The case was a 77-year-old man. He had dizziness and dysphagia for 2 years, and underwent detailed screening at the internal medicine department for general malaise and bloody sputum. He was hospitalized for aspiration pneumonia due to dysphagia of unknown origin. This time, he visited a local doctor with palpitations and shortness of breath. Echocardiography indicated a left atrial tumor involving the mitral valve and arrhythmia. Emergency surgery was performed to remove the left atrial myxoma and close the patch at our hospital's cardiovascular surgery department. After the excision, swallowing function was restored, and the patient was diagnosed with postoperative Ortner's syndrome. We report a case where echocardiography was considered important as a detailed investigation of the cause of swallowing dysfunction and dizziness.

The World Health Organization recommends that countries or organizations that host mass gatherings plan ahead and prepare for possible public health events to ensure a safe environment for local residents, participants and travellers.1 Public health events during mass gatherings can also affect non-host countries. There are numerous reports of the spread of infectious diseases by travellers returning from mass gatherings,2 which can potentially pose the risk of an outbreak of new infectious diseases to travellers’ home countries. With more frequent travel across borders, it is prudent that non-host countries prepare for mass gathering events.