Accessory tricuspid valve tissue is a rare heart condition that people are born with. It involves extra tissue on the tricuspid valve, one of the heart's valves that helps control blood flow. This extra tissue can be fixed or move around, and it is often seen together with other congenital heart anomalies such as atrial septal defect, ventricular septal defect, transposition of the great arteries, and tetralogy of Fallot. The presence of accessory tricuspid valve tissue can affect how the heart works, and people with this condition may notice symptoms like a heart murmur, difficulty breathing (dyspnea), or a bluish tint to the skin (cyanosis). These signs may vary in severity depending on which other heart anomalies are also present. The condition has been recognized as a form of congenital (present from birth) malformation affecting the heart’s structure.

People with accessory tricuspid valve tissue may experience a systolic heart murmur, which is an unusual sound made by the heart. In some cases, they may also have difficulty breathing (dyspnea) or show signs of cyanosis, a bluish discoloration of the skin. The symptoms often relate to the extra valve tissue and any associated congenital heart anomalies.

Accessory tricuspid valve tissue is a congenital condition, meaning it is present from birth. It is caused by an abnormal development of the heart’s structures, leading to extra tissue on the tricuspid valve. This condition is usually associated with other congenital heart anomalies. Information about specific genetic factors or risk factors is currently limited.