Feng Shuyi, Wang Hongping, He Xinyi, Kong Pengxu, Wu Fan, Wang Shizhao, Pan Xiangbin, He Guowei
Department of Structural Heart Disease, National Center for Cardiovascular Disease, China & Fuwai Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
Key Laboratory of Innovative Cardiovascular Devices, Chinese Academy of Medical Sciences, Beijing, China.
JTCVS Open. 2025 Jun 24;26:104-114. doi: 10.1016/j.xjon.2025.06.012. eCollection 2025 Aug.
Left ventricular vortex dynamics play a crucial role in cardiac function but are significantly altered by mitral valve diseases or surgical interventions. Such hemodynamic changes may lead to maladaptive intracardiac vortices, potentially triggering pathways associated with progressive left ventricular remodeling and thrombosis. This study assessed left ventricular hemodynamics under both physiological and pathological conditions using a biohybrid in vitro platform, aiming to analyze the impact of these conditions on cardiac function.
An in vitro platform was established to simulate 6 mitral valve conditions: healthy, mitral regurgitation, bioprosthetic valve replacement, mechanical valve replacement (in 2 orientations), and transcatheter mitral valve edge-to-edge repair. Flow fields within the left ventricle were captured using 4-dimensional particle image velocimetry, including mean flow fields, vortex depth, vortex transversal position, viscous shear stress, and energy dissipation.
Mitral regurgitation preserved vortex structure compared with healthy conditions. Mechanical valves altered vortex direction and reduced vortex transversal position (0.66-0.47, < .001), potentially impairing pump efficiency and increasing cardiac workload. Bioprosthetic valves displaced the vortex away from the apex, decreasing vortex depth (0.64-0.32, < .001), which may elevate apical thrombosis risk. Transcatheter mitral valve edge-to-edge repair reduced mitral regurgitation but significantly increased energy dissipation and viscous shear stress, indicating higher cardiac energy expenditure and disturbed flow.
Preserving native valve function optimizes left ventricular hemodynamics, whereas valve replacements and transcatheter mitral valve edge-to-edge repair alter flow patterns, increasing cardiac workload and thrombotic risks. These findings underscore the importance of assessing left ventricular flow dynamics in the treatment of mitral regurgitation.
左心室涡流动态在心脏功能中起着关键作用，但会因二尖瓣疾病或手术干预而发生显著改变。这种血流动力学变化可能导致适应性不良的心内涡流，潜在地触发与左心室进行性重塑和血栓形成相关的途径。本研究使用生物杂交体外平台评估生理和病理条件下的左心室血流动力学，旨在分析这些条件对心脏功能的影响。
建立一个体外平台来模拟6种二尖瓣状况：健康、二尖瓣反流、生物瓣置换、机械瓣置换（两种方向）以及经导管二尖瓣缘对缘修复。使用四维粒子图像测速技术捕获左心室内的流场，包括平均流场、涡深度、涡横向位置、粘性剪切应力和能量耗散。
与健康状况相比，二尖瓣反流保留了涡结构。机械瓣改变了涡的方向并减小了涡横向位置（0.66 - 0.47，P <.001），可能损害泵血效率并增加心脏负荷。生物瓣使涡远离心尖移位，减小了涡深度（0.64 - 0.32，P <.001），这可能增加心尖血栓形成风险。经导管二尖瓣缘对缘修复减少了二尖瓣反流，但显著增加了能量耗散和粘性剪切应力，表明心脏能量消耗更高且血流紊乱。
保留天然瓣膜功能可优化左心室血流动力学，而瓣膜置换和经导管二尖瓣缘对缘修复会改变血流模式，增加心脏负荷和血栓形成风险。这些发现强调了在二尖瓣反流治疗中评估左心室血流动力学的重要性。
