Diseases of the tricuspid valve

Diseases of the tricuspid valve form a wide range of anomalies that range from benign to critical conditions. Some of these malformations are unsuitable for the creation of a biventricular circulation. Tricuspid atresia is a rare defect characterized by either an absent right atrio-ventricular connection, with the right atrium and ventricle completely disconnected by the atrio-ventricular sulcus, or an imperforate tricuspid valve.

The key features of Ebstein’s anomaly are the underdevelopment of the septal leaflet of the tricuspid valve, septal leaflet displacement toward the apex of the heart and in many patients spiral displacement of the septal and anterosuperior leaflet toward the right ventricular outflow tract. In more severe forms of the disease, the inferior leaflet is also affected and often undeveloped. The antero-superior leaflet is usually elongated, tethered to the right ventricular free wall and may have fenestrations. In some cases, the functional right ventricle is very hypoplastic due to the presence of a large atrialized portion. Significant tricuspid regurgitation and right ventricular dysfunction are often present.

Tricuspid valve dysplasia is an umbrella term for a range of abnormalities characterized by malformed tricuspid valve leaflets, chordae tendineae, and papillary muscles, resulting in tricuspid regurgitation rather than stenosis. Overriding and/or straddling of the tricuspid valve is generally associated with complex cardiac defects. Acquired tricuspid valve disease is rarely seen in patients with rheumatic heart disease or after previous cardiac interventions.