Pirola Sergio, Pirola Selene, Mastroiacovo Giorgio, Bonomi Alice, Manchester Emily L, Fisichella Serena M, Maragna Riccardo, Baggiano Andrea, Mushtaq Saima, Muscogiuri Giuseppe, Guglielmo Marco, Yun Xu Xiao, Pontone Gianluca, Polvani Gianluca
Department of Cardiovascular Surgery, IRCCS Centro Cardiologico Monzino, Milan, Italy.
Institute of Clinical Sciences, Imperial College London, London, UK.
Eur J Cardiothorac Surg. 2023 Dec 1;64(6). doi: 10.1093/ejcts/ezad299.
Aortic valve neocuspidalization aims to replace the 3 aortic cusps with autologous pericardium pre-treated with glutaraldehyde, and it is a surgical alternative to the classical aortic valve replacement (AVR). Image-based patient-specific computational fluid dynamics allows the derivation of shear stress on the aortic wall [wall shear stress (WSS)]. Previous studies support a potential link between increased WSS and histological alterations of the aortic wall. The aim of this study is to compare the WSS of the ascending aorta in patients undergoing aortic valve neocuspidalization versus AVR with biological prostheses.
This is a prospective nonrandomized clinical trial. Each patient underwent a 4D-flow cardiac magnetic resonance scan after surgery, which informed patient-specific computational fluid dynamics models to evaluate WSS at the ascending aortic wall. The adjusted variables were calculated by summing the residuals obtained from a multivariate linear model (with ejection fraction and left ventricle outflow tract-aorta angle as covariates) to the mean of the variables.
Ten patients treated with aortic valve neocuspidalization were enrolled and compared with 10 AVR patients. The aortic valve neocuspidalization group showed a significantly lower WSS in the outer curvature segments of the proximal and distal ascending aorta as compared to AVR patients (P = 0.0179 and 0.0412, respectively). WSS levels remained significantly lower along the outer curvature of the proximal aorta in the aortic valve neocuspidalization population, even after adjusting the WSS for the ejection fraction and the left ventricle outflow tract-aorta angle [2.44 Pa (2.17-3.01) vs 1.94 Pa (1.72-2.01), P = 0.02].
Aortic valve neocuspidalization hemodynamical features are potentially associated with a lower WSS in the ascending aorta as compared to commercially available bioprosthetic valves.
主动脉瓣新瓣叶化旨在用经戊二醛预处理的自体心包替代3个主动脉瓣叶，是经典主动脉瓣置换术（AVR）的一种手术替代方案。基于图像的患者特异性计算流体动力学可得出主动脉壁上的剪应力[壁面剪应力（WSS）]。先前的研究支持WSS升高与主动脉壁组织学改变之间存在潜在联系。本研究的目的是比较接受主动脉瓣新瓣叶化手术的患者与接受生物假体AVR患者升主动脉的WSS。
这是一项前瞻性非随机临床试验。每位患者术后均接受了4D流心脏磁共振扫描，该扫描为患者特异性计算流体动力学模型提供信息，以评估升主动脉壁的WSS。通过将多变量线性模型（以射血分数和左心室流出道-主动脉角度作为协变量）得到的残差与变量均值相加来计算调整后的变量。
纳入10例接受主动脉瓣新瓣叶化治疗的患者，并与10例AVR患者进行比较。与AVR患者相比，主动脉瓣新瓣叶化组在升主动脉近端和远端外曲率段的WSS显著更低（分别为P = 0.0179和0.0412）。即使在将WSS校正射血分数和左心室流出道-主动脉角度后，主动脉瓣新瓣叶化人群近端主动脉外曲率处的WSS水平仍显著更低[2.44 Pa（2.17 - 3.01）对1.94 Pa（1.72 - 2.01），P = 0.02]。
与市售生物假体瓣膜相比，主动脉瓣新瓣叶化的血流动力学特征可能与升主动脉中较低的WSS相关。
