title: Criteria to detect mitral prosthetic valve dysfunction via continuous wave Doppler echocardiography.
abstract: To detect the diagnostic criteria for mitral prosthetic valve dysfunction, Doppler echocardiography was used to assess valve function following mitral valve replacement in 100 patients [50 with St. Jude Medical (SJM) valves, 50 with Björk-Shiley (B-S) valves]. Mitral valve area (MVA) was calculated by dividing a constant of 220 by pressure half time (PHT) measured via Doppler technique [220/PHT]. The relationship of MVA to left ventricular function, geometric valve area (GVA) of the prosthetic valve, body surface area (BSA), and maximum disc-opening angle (maxOA) were assessed. In the SJM valves, MVA significantly correlated with valve area index (GVA/BSA). The % area index [(MVA/valve area index) x 100] was 100.2 +/- 12.8% on the average and no patients with the SJM valve showed the %area index of less than 73%. There was no incidence of valve dysfunction in the SJM valves. We concluded from these results that if the % area index is less than 73% (mean -2SD), the SJM valve dysfunction should be diagnosed. When the B-S valves were examined, there were 19 patients in whom the maximum opening angle had decreased to under 58 degrees. These patients also had decreased MVA and % area index. Evaluation of the relationship between the maximum opening angle and the % area index revealed that the patients in whom the maximum opening angle had diminished to under 50 degrees had low % area index (of less than 70%).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Cardiovascular Surgery, Okayama University Medical School, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Shigenobu
authors.forename: S
authors.initials: S
authors.lastname: Sano
mesh_terms: D000328:Adult; D000368:Aged; D001830:Body Surface Area; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D006439:Hemodynamics; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000601:surgery; D012086:Reoperation / Q000706:statistics & numerical data; D012720:Severity of Illness Index; D013997:Time Factors; D016277:Ventricular Function, Left