The tricuspid valve is on the right side of the heart, between the right atrium and the right ventricle. The normal tricuspid valve usually has three leaflets and three papillary muscles. Tricuspid valves may also occur with two or four leaflets, and the number may change during life[citation needed].
A small amount of leakage or regurgitation is not uncommon in the tricuspid valve. It is a common valve to be infected (endocarditis) in IV drug users.
The tricuspid valve can be affected by rheumatic fever which can cause tricuspid stenosis or tricuspid regurgitation.
Some patients are born with congenital abnormalities of the tricuspid valve. Congenital apical displacement of the tricuspid valve is called Ebstein's anomaly and typically causes significant tricuspid regurgitation.
right heart: (vena cavae, coronary sinus) → right atrium (fossa ovalis) → tricuspid valve → right ventricle → pulmonic valve → (pulmonary artery and pulmonary circulation)
left heart: (pulmonary veins) → left atrium → mitral valve → left ventricle → aortic valve → (aorta, aortic sinus and systemic circulation)
pericardium | epicardium | endocardium | myocardium
conduction system: cardiac pacemaker | Purkinje fibers | bundle of His | SA node | AV node