Dal Lin Carlo, Bottio Tomaso, Buratto Edward, Tarzia Vincenzo, Rizzoli Giulio, Savona Valentina, Gerosa Gino
Division of Cardiac Surgery, Department of Cardiac, Thoracic and Vascular Sciences, Padua University Medical School, Padova, Italy.
J Heart Valve Dis. 2012 Jan;21(1):112-7.
Previous studies have shown that the Carpentier-Edwards Magna (CEM) valve is an excellent bioprosthesis in terms of its systolic performance; indeed, it has been described as 'a stented valve with stentless performance'. However, valve performance is not only a matter of gradients; it is also necessary to evaluate the diastolic-phase performance. Previous in-vitro studies have shown that the CEM has an excessive total regurgitant volume. Hence, the study aim was to compare the hydrodynamics of the CEM, with the newly evolved version of this valve, the CEM Ease (CEME).
The CEM and CEME valves (both 21 mm) were tested in the aortic chamber (23 mm diameter) of the Sheffield pulse duplicator. The tests were carried out at increasing pulse rates (PR; 70-100 beats/min), and at each pulse rate the valve was tested at different stroke volumes (SVs; 45-65 ml). The forward-flow pressure drop, closing leakage volumes and effective orifice area (EOA) were recorded.
The CEM and CEME valves showed a comparable systolic-phase performance, there being no significant differences in terms of transvalvular gradient, EOA and stroke work loss, regardless of the PR and SV. In fact, the new CEME exhibited a significantly improved diastolic performance, with the total regurgitant volume being significantly lower, due especially to a reduced leakage volume and, to a lesser extent, a reduced closing volume.
The study results indicated that the new CEME valve would maintain the excellent systolic performance of the previous CEM model, but with a significantly improved diastolic performance.
既往研究表明，就收缩期性能而言，卡彭蒂埃-爱德华兹麦格纳（CEM）瓣膜是一种出色的生物假体；实际上，它被描述为“具有无支架性能的带支架瓣膜”。然而，瓣膜性能不仅关乎压力阶差；评估舒张期性能也很有必要。既往体外研究表明，CEM的总反流容积过大。因此，本研究的目的是比较CEM与该瓣膜新改进版本卡彭蒂埃-爱德华兹麦格纳易安（CEME）瓣膜的流体动力学性能。
在谢菲尔德脉动复制仪的主动脉腔（直径23mm）中对CEM和CEME瓣膜（均为21mm）进行测试。测试在逐渐增加的脉率（PR；70 - 100次/分钟）下进行，并且在每个脉率下，瓣膜在不同的搏出量（SV；45 - 65ml）下进行测试。记录正向血流压力降、关闭漏血容积和有效瓣口面积（EOA）。
无论PR和SV如何，CEM和CEME瓣膜在收缩期性能方面表现相当，跨瓣压力阶差、EOA和搏功损失方面均无显著差异。事实上，新型CEME瓣膜的舒张期性能显著改善，总反流容积显著降低，这尤其归因于漏血容积减少，在较小程度上也归因于关闭容积减少。
研究结果表明，新型CEME瓣膜将保持先前CEM型号出色的收缩期性能，但舒张期性能显著改善。
