Mild regurgitation of the mitral valve is usually caused by the following: 1. For mitral and tricuspid regurgitation, which is usually caused by atherosclerosis, mild regurgitation of the mitral and tricuspid valves occurs as patients age. 2. If a patient has a significant overdose of medication, such as taking ergometrine, this can also increase the risk of mild regurgitation of the mitral and tricuspid valves. 3. 4. Traumatic causes or excessive exercise can also lead to mild regurgitation of the mitral and tricuspid valves. 5. If the patient develops significant atrial fibrillation, mitral and tricuspid regurgitation can also occur. 6. If severe coronary artery disease occurs, leading to severe arrhythmias, or if acute coronary syndrome occurs, the patient can develop tendon rupture, and papillary muscle ischemia, when the above clinical symptoms and manifestations will also occur.