Tricuspid regurgitation as a manifestation of an isolated congenital anomaly of the tricuspid valve is rare. Cross-sectional and color Doppler echocardiography allow improved evaluation of tricuspid valvar function. As a result, the heterogeneous category of congenital tricuspid valvar dysplasia may be better understood from a functional point of view. We are reporting a distinct entity in which tricuspid valvar regurgitation results from failure of coaptation due to short tendinous cords tethering the septal leaflet.

Three children with significant primary tricuspid regurgitation were evaluated, treated, and followed. On echocardiographic evaluation, a central regurgitant jet of moderate or severe degree was directed toward the atrial septum through poorly coapting tricuspid valvar leaflets, which did not approximate due to tethering of the septal leaflet by abnormally short cords. In one patient, the tricuspid valve was otherwise normal; in the other two the leaflets and cords were also thickened. Two patients underwent surgery at 9 and 11 years of age. The cords tethering the septal leaflet were augmented by interposing appropriate lengths of expanded polytetrafluoroethylene suture and performing commissural annuloplasty. Both patients are asymptomatic 33 and 42 months postoperatively, with mild residual tricuspid regurgitation that has not changed since surgery. The other patient, an 8 month-old infant, has not yet undergone surgery.

Asymmetric tendinous cords of the tricuspid valve causing tethering of the septal leaflet is a distinct cause of tricuspid regurgitation that can be recognized with echocardiography. Although rare, the importance of recognizing this lesion lies in its being readily amenable to surgical repair.