title: Doppler echocardiographic evaluation of prosthetic valves in tricuspid position.
abstract: Doppler echocardiographic characteristics of 29 normally functioning prosthetic valves (23 mechanical, 6 biological) and 8 obstructed mechanical prostheses in the tricuspid position are reported. In normally functioning prostheses, peak velocity, mean pressure gradient, and pressure-half time were 1.25 +/- 0.18 m x sec(-1), 2.6 +/- 1.1 mm Hg, and 122.6 +/- 30.7 msec, respectively. Although no significant differences were seen in peak velocity and mean pressure gradient between mechanical and biological valves, the pressure half-time was significantly greater in biological valves. All normally functioning prostheses had a mean pressure gradient 5.5 mm Hg and pressure half-time < 200 msec. In obstructed bileaflet valves, peak velocity was 1.66 +/- 0.28 m x sec(-1), mean pressure gradient was 6.1 +/- 2.8 mm Hg, and pressure half-time was 265.8 +/- 171.7 msec. These Doppler data were significantly greater than those in normally functioning valves where the mean pressure gradient was 5.1 mm Hg and the pressure half-time was 156 msec in all except one patient. Pathological obstruction of a tricuspid prosthesis can be strongly suspected in patients with a mean pressure gradient > 5.5 mm Hg and a pressure half-time > 200 msec on Doppler echocardiography.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006350:Heart Valve Prosthesis; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D012016:Reference Values; D014261:Tricuspid Valve / Q000000981:diagnostic imaging*