Echocardiographic evaluation of normal and prolapsed tricuspid valve leaflets.

The tricuspid valve was examined by 2-dimensional (2-D) echocardiography in 14 patients with tricuspid valve prolapse (TVP) and in 16 normal subjects. Individual leaflets were identified anatomically and for frequency of prolapse. Maximal and minimal anular sizes were measured. Multiple tomograms of the tricuspid anulus were recorded at 30 degrees intervals around the tricuspid anulus with the transducer placed at the right ventricular apex. Anuli were reconstructed from the 6 planes and corrected for body surface area. Three leaflets of the tricuspid valve could be anatomically identified in all patients. Prolapse of all 3 leaflets was observed in 6 patients, 2 leaflets in 5 and 1 in 3. Frequency of individual leaflet prolapse was 93% for the septal cusp, 86% for the anterior and 43% for the posterior. Maximal anular circumference and area in TVP were 7.9 +/- 0.6 and 8.9 +/- 1.3 cm2/m2, respectively--significantly larger than values in normal subjects (6.4 +/- 0.5 cm/m2 and 6.1 +/- 0.9 cm2/m2, respectively) (p less than 0.001). Percent reductions in circumference and area in TVP were 14 +/- 3 and 25 +/- 5%, respectively--significantly smaller values than in normal subjects (19 +/- 4 and 33 +/- 4%, respectively). Tricuspid regurgitation (TR) was detected by contrast echocardiography in 7 of 14 patients with TVP. The severity of TR appeared to be minimal in 6 of the 7 patients, and was not associated with an increase in anular size. Thus, TVP is associated with anular dilatation irrespective of associated TR, probably as a primary pathologic characteristic.