title: [Hemodynamic evaluation of GK and Medtronic-Hall prosthetic mitral valves by exercise Doppler echocardiography].
abstract: Hemodynamic alterations were studied in 42 patients with GK and Medtronic-Hall (M-H) prosthetic valves by stress Doppler echocardiography after submaximal supine exercise. In the GK group, peak and mean gradients increased from 10.1 +/- 1.7 and 3.4 +/- 1.3 mmHg respectively, at rest to 15.3 +/- 3.1 and 5.4 +/- 1.5 mmHg at peak exercise (mean +/- s), mitral valve area increased from 2.61 +/- 0.34 cm2 at rest to 2.86 +/- 0.45 cm2 at peak exercise (P < 0.05). In the M-H group, peak and mean gradients increased from 11.3 +/- 1.8 and 4.3 +/- 1.0 mmHg respectively, at rest to 15.0 +/- 1.9 and 5.8 +/- 1.5 mmHg at peak exercise. Mitral valve area increased from 2.66 +/- 0.43 cm2 at rest to 2.94 +/- 0.38 cm2 at peak exercise (P < 0.05). The results showed that peak and mean gradients at rest in patients with GK prosthetic valve were lower than those of M-H group. But after exercise, the two prosthetic valves showed similar characteristics in hemodynamics. Exercise Doppler echocardiography is a simple, noninvasive and reliable method for the evaluation of the function of mechanical mitral prostheses.
authors.affiliation: Cardiovascular Institute, Chinese Academy of Medical Sciences, Beijing.
authors.forename: C M
authors.initials: CM
authors.lastname: Fan
mesh_terms: D000328:Adult; D015150:Echocardiography, Doppler; D005069:Evaluation Studies as Topic; D005080:Exercise Test; D005260:Female; D006349:Heart Valve Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology; D006350:Heart Valve Prosthesis; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008943:Mitral Valve