Tasca Giordano, Vismara Riccardo, Mangini Andrea, Romagnoni Claudia, Contino Monica, Redaelli Alberto, Fiore Gianfranco Beniamino, Antona Carlo
Cardiovascular Department, Cardiac Surgery Unit, Ospedale "A. Manzoni" di Lecco, Lecco; Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Milan.
Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Milan; FoRCardioLab, Fondazione per la Ricerca in Cardiochirurgia ONLUS, Milan.
Ann Thorac Surg. 2017 Jan;103(1):139-144. doi: 10.1016/j.athoracsur.2016.05.089. Epub 2016 Aug 17.
Aortic valve replacement has evolved recently with the development of the sutureless bioprosthesis. One such valve is the Perceval bioprosthesis, which is built by mounting leaflets of bovine pericardium to a thin stent; this approach has the potential to provide an excellent fluid dynamic performance. We undertook an in vitro study to compare the hydrodynamic performance of the sutureless bioprosthesis with two standard pericardial stented bioprostheses (Crown and Magna).
Tests were conducted using a mock loop, testing on two sizes of the three prostheses. The prosthesis sizes were chosen to house the valves in porcine aortic roots with a native annulus diameter of 19 mm (n = 6) or 21 mm (n = 6). The stroke volume ranged from 25 mL to 105 mL at a simulated heart rate of 70 beats per minute.
Mean pressure drop and energy loss rose with increasing stroke volume in all of the valves tested (p < 0.001), with the sutureless valve showing the lowest values for both variables (p < 0.001). Effective orifice area values were stable across the stroke volume intervals and were larger in the sutureless valves (p < 0.001).
All of the valves tested provided good fluid dynamic performances. The sutureless bioprosthesis provided the best performance with the least hindrance to flow behavior. From the hydrodynamic perspective, the sutureless prosthesis may present an advance in the evolution of bioprostheses, ensuring low gradients and potential for low incidence of patient-prosthesis mismatch even in small annuli.
随着无缝合生物瓣膜的发展,主动脉瓣置换术近来不断演变。其中一种瓣膜是Perceval生物瓣膜,它是通过将牛心包瓣叶安装到一个薄支架上制成的;这种方法有可能提供出色的流体动力学性能。我们进行了一项体外研究,以比较无缝合生物瓣膜与两种标准心包带支架生物瓣膜(Crown和Magna)的流体动力学性能。
使用模拟循环进行测试,对三种瓣膜的两种尺寸进行检测。选择瓣膜尺寸以便将瓣膜置于天然瓣环直径为19毫米(n = 6)或21毫米(n = 6)的猪主动脉根部。在模拟心率为每分钟70次搏动的情况下,每搏量范围为25毫升至105毫升。
在所有测试瓣膜中,平均压力降和能量损失均随每搏量增加而升高(p < 0.001),无缝合瓣膜在这两个变量上的值均最低(p < 0.001)。有效瓣口面积值在每搏量区间内保持稳定,且在无缝合瓣膜中更大(p < 0.001)。
所有测试瓣膜均具有良好的流体动力学性能。无缝合生物瓣膜表现最佳,对血流行为的阻碍最小。从流体动力学角度来看,无缝合瓣膜可能代表了生物瓣膜发展的一个进步,即使在小瓣环情况下也能确保低梯度以及患者-假体不匹配发生率低的可能性。