Mitral valve regurgitation is classified into mild, moderate, and severe categories. Generally speaking, patients with mild and some moderate regurgitation may not exhibit symptoms. However, a small proportion of patients with moderate or severe regurgitation might experience symptoms such as tightness after activity and difficulty breathing. If these conditions recur, there may be an indication for surgical intervention. Therefore, for patients with moderate to severe symptoms, or those with significant enlargement of the heart, it is recommended to consider surgery at an early stage. If patients with mild or some moderate mitral valve regurgitation are asymptomatic and do not show significant enlargement of the heart structure, medical treatment or observation without valve replacement can be considered.