Tricuspid regurgitation is a heart condition where the tricuspid valve, located between the right atrium and right ventricle, does not close properly. This malfunction allows blood to flow backward into the right atrium when the right ventricle contracts, which can lead to various symptoms. Common causes of tricuspid regurgitation include heart valve disease, pulmonary hypertension, and right heart enlargement. Symptoms may include fatigue, swelling in the legs and abdomen, and shortness of breath. Diagnosis typically involves echocardiography to assess the valve's function and the heart's overall condition.