Prolapse of the anterior leaflet of the mitral valve can lead to symptoms of chest tightness, shortness of breath, dyspnea, and can result in heart failure and left heart enlargement. In advanced stages, pulmonary hypertension can develop, leading to right ventricular hypertrophy, right heart failure, and eventually total heart failure. Most mitral valve prolapse is a primary mucinous lesion of the mitral valve, which causes the leaflets to become loose, dilated, or overly long, and when the heart contracts, the leaflets suddenly protrude into the left atrium, resulting in mitral valve insufficiency. Some mitral valve prolapse is associated with connective tissue disease, such as Marfan syndrome.