What does tricuspid regurgitation mean?

Tricuspid regurgitation is caused by a small amount of blood flowing back into the atrium when the mitral valve is not tightly closed during cardiac contraction. There are many reasons for causing a small amount of tricuspid regurgitation. If it is mild regurgitation, it is considered to be physiological phenomenon. If it is serious regurgitation, it is considered to be incomplete cardiac valve closure.