Patient-prosthesis mismatch may be irrelevant after aortic valve replacement with the 19-mm Perimount pericardial bioprosthesis in patients aged 65 years or older

Valve prosthesis-patient mismatch (VP-PM): a long-term perspective

The concept/phenomenon of valve prosthesis/patient mismatch (VP-PM), described in 1978, has stood the test of time. From that time to 2011, VP-PM has received a great deal of attention but studies have come to varying conclusions. This is largely because of the determination of prosthetic heart valve area [called effective orifice area index (EOAi)] by projection rather than by actual measurement, variable criteria to assess severity of EOAi and the timing of determination of EOAi. All prosthetic heart valves have some degree of VP-PM which must be placed in a proper clinical perspective. This can be done by determining its effects on function and outcomes. For mortality one needs to focus especially on severe/critical degree of VP-PM and determine the cause of death was due to VP-PM. For the period "beyond 2011" a road map is suggested that will have uniformity of assessment of VP-PM and a focusing on the important goals of VP-PM.

Clinical outcomes and hemodynamics of the 19-mm Perimount Magna bioprosthesis in an aortic position: comparison with the 19-mm Medtronic Mosaic Ultra Valve

BACKGROUND

When aortic valve replacement is performed in patients with a small aortic annulus, prosthesis-patient mismatch (PPM) is of concern because it can affect postoperative clinical outcomes. Although larger bioprosthetic valves have been well studied, the hemodynamics of 19-mm bioprostheses have been reported in only a small number of patients. The effectiveness as well as the impact of PPM on outcomes are thus still unclear.

METHODS AND RESULTS

Postoperative clinical and hemodynamic variables were compared in 67 patients with a 19-mm Carpentier Edwards Perimount Magna bioprosthesis and in 10 patients with a 19-mm Medtronic Mosaic Ultra valve. Mean follow-up time was 13 months. There was no in-hospital mortality. Echocardiography 6.5±4.0 months after surgery showed significant decreases in the mean left ventricular (LV)-aortic pressure gradient, and decreases in the mean LV mass index. Reduction in LV mass index did not differ between the valve groups, despite a higher pressure gradient in the Mosaic group. Although PPM was detected in 21 patients in the Magna group, it did not affect regression of the LV mass index during the follow-up period.

CONCLUSIONS

Use of the 19-mm Magna bioprosthesis appears to provide satisfactory clinical results. LV-aortic pressure gradient was lower in the Magna group. The present data suggest that PPM is not related to reduction in the LV mass index.

Beginning and development of surgery for acquired valvular heart disease in Japan

The initiation and development of surgery for acquired valvular heart disease in Japan was reviewed. The first series of attempts at closed valvular surgery were performed in 1951-1952 by collaboration between the brothers Tohru and Shigeru Sakakibara in patients with pulmonary or mitral stenosis. During the popularization of closed valvular surgery, open heart surgery under direct vision was successfully performed by Shigeru Sakakibara with cooling of the body in 1954 and by using cardiopulmonary bypass (CPB) in 1956. With the development of CPB and artificial heart valves, closed valvular heart surgery was replaced by open surgery, which expanded rapidly during the 1960s and 1970s. Along with the serial introduction and improvement of mechanical vales thereafter, bioprosthetic valves were also introduced and were adopted for certain patients. Use of bioprosthetic valves in the aortic position exceeded 50% in 2005, along with the increase of elderly patients. Although trials of mitral valve plasty for mitral regurgitation were first done during the 1950s to 1960s in Japan, interest in valve plasty only increased during the late 1970s. Considering the patient's quality of life and the long-term results, mitral valve plasty became the major procedure (exceeding valve replacement) from 2004. In 2002, the Guideline for Surgical and Interventional Treatment of Valvular Heart Disease was published by a joint committee of the relevant academic societies, and it has made an important contribution to improving surgical outcomes.