Echocardiographic assessment of long-term hemodynamic characteristics of mechanical mitral valve prostheses with different mitral valvular diseases.

Mitral stenosis (MS) and mitral insufficiency (MI) have different pre-operative hemodynamic characteristics. However, it is unclear if there are differences in long-term echocardiographic characteristics of MS and MI patients after mechanical mitral valve replacement. This study is to compare long-term echocardiographic results of mechanical mitral valve prostheses between MS and MI patients. From January 2003 to January 2009, a total of 199 consecutive patients were recruited in this study. Patients were classified as group MS (n = 123) and MI (n = 76) according to the manifestation of mitral valvular disease. The mean age for patients was 50.1 ± 10.5 years and follow-up time was 7.2 ± 2.0 years. The MS after operation were more likely to experience atrial fibrillation (p = 0.002). The New York Heart Association (NYHA) class in MI showed a greater improvement (p = 0.006) than in MS. The left ventricular end-diastolic dimension (LVEDD) (p = 0.010) and stroke volume (SV) (p = 0.000) in MI were still larger than that in MS patients. These differences did not disappear with time after operation. The long-term echocardiographic results of mechanical mitral valve prostheses between MS and MI patients are significantly different. Over a long-term follow up, MI patients still have a larger LVEDD and SV than MS, and associated with a greater improvement of NYHA class.

[Doppler echocardiographic assessment of CarboMedics prosthesis in patients with mitral valve replacement].

OBJECTIVE: To evaluate the CarboMedics (CM) prosthesis function two years after mitral valve replacement, and to compare the effective orifice area (EOA) calculated by pressure half-time (PHT) method and continuity method (CON). METHODS: Forty nine patients who underwent isolated mitral valve replacement with a CM prosthesis were recruited in this study, which included 13 cases of 25 mm CM prosthesis and 36 cases of 27 mm CM prosthesis. Two years after the mitral valve replacement, transthoracic echocardiography (TTE) was performed, measuring left ventricular ejection fraction (LVEF), stroke volume mean gradient (SV), PHT, peak early mitral diastolic velocity (E velocity), mean gradient (MG), time-velocity integral of left ventricular outflow tract/time-velocity integral of mitral valve prosthesis (TVI(MVP)/TVI(LVOT)). The function of the prosthetic valve was considered normal when PHT < 130 ms, E velocity < 2.0 m/s and TVI(MVP)/TVI(LVOT) < 2.2. RESULTS: More than half (53.1%) of the patients had normal function of the prosthetic valve. No significant differences were found in PHT, MG, TVI(MVP)/TVI(LVOT), EOA or IEOA between the patients with 25 mm valve and the patients with 27 mm valve (P > 0.05). But the patients with 25 mm valve had higher E velocity than the patients with 27 mm valve (P < 0.05). The PHT method produced greater EOA than by the CON method (P < 0.05). CONCLUSION: The function of CM prosthesis is acceptable two years after the mitral valve replacement, with most patients having PHT < 130 ms, E velocity < 2.0 m/s and TVI(MVP)/TVI(LVOT) < 2.2. PHT method produces greater EOA than CON method.