The tricuspid valve annulus: study of size and motion in normal subjects and in patients with tricuspid regurgitation.

Abstract
The tricuspid valve leaflets and their annular attachments were recorded by two-dimensional echocardiography from a view of the right ventricular inflow tract obtained by placing the transducer at an intermediate position between the left ventricular apex and the left lower sternal border. The transducer was rotated, and recordings were made at 30 degrees rotational intervals around the circumference of the tricuspid valve annulus. The cyclical pattern of variations in tricuspid annular size was studied with 12 measurements made during the cardiac cycle in five normal subjects. Annular areas and circumferences were measured. The overall motion pattern was similar to that reported in normal mitral valve annular study. Subsequently, in 16 normal subjects and 18 patients with tricuspid regurgitation, the maximum and minimum tricuspid annular sizes and their percent reduction were measured. The mean maximum annular circumference and area were 11.9 +/- 0.9 cm (mean +/- SD) and 11.3 +/- 1.8 cm2 in normal subjec...