CPT® Code 33420

Mitral valvotomy, also known as commissurotomy, is a surgical procedure aimed at treating mitral stenosis, a condition characterized by the narrowing of the mitral valve orifice. This narrowing obstructs the flow of blood from the left atrium to the left ventricle, which can lead to various complications, including heart failure. The mitral valve is situated between the left atrium and the left ventricle, playing a crucial role in maintaining proper blood circulation within the heart. The most prevalent cause of mitral stenosis is rheumatic heart disease, which can result from rheumatic fever. Other contributing factors include calcification of the mitral annulus, infective endocarditis, systemic lupus erythematosus, rheumatoid arthritis, and carcinoid heart disease. The procedure coded as CPT® 33420 specifically refers to a closed heart approach for performing a mitral valve commissurotomy. During this procedure, access to the heart is achieved through a right anterolateral thoracotomy at the fifth intercostal space, allowing the surgeon to expose the heart and perform the necessary interventions to alleviate the obstruction caused by the stenosis.