Department of Cardiothoracic Surgery, Stanford University, 870 Quarry Rd, Stanford, CA, 94304, USA.
Department of Bioengineering, Stanford University, 443 Via Ortega, Stanford, CA, 94305, USA.
Ann Biomed Eng. 2023 Aug;51(8):1738-1746. doi: 10.1007/s10439-023-03178-1. Epub 2023 Mar 25.
Single ventricle physiology (SVP) is used to describe any congenital heart lesion that is unable to support independent pulmonary and systemic circulations. Current treatment strategies rely on a series of palliation surgeries that culminate in the Fontan physiology, which relies on the single functioning ventricle to provide systemic circulation while passively routing venous return through the pulmonary circulation. Despite significant reductions in early mortality, the presence of atrioventricular valve (AVV) regurgitation is a key predictor of heart failure in these patients. We sought to evaluate the biomechanical changes associated with the AVV in SVP physiologies. Left and right ventricles were sutured onto patient-derived 3D-printed mounts and mounted into an ex vivo systemic heart simulator capable of reproducing Norwood, Glenn, Fontan and Late Fontan physiologies. We found that the tricuspid anterior leaflet experienced elevated maximum force, average force, and maximum yank compared to the posterior and septal leaflets. Between physiologies, maximum yank was greatest in the Norwood physiology relative to the Glenn, Fontan, and Late Fontan physiologies. These contrasting trends suggest that long- and short-term mechanics of AVV failure in single ventricle differ and that AVV interventions should account for asymmetries in force profiles between leaflets and physiologies.
单心室生理学（SVP）用于描述任何无法支持独立肺循环和体循环的先天性心脏病变。目前的治疗策略依赖于一系列姑息性手术，最终达到 Fontan 生理学，它依赖于单个功能心室为体循环提供动力，同时通过肺循环被动输送静脉回流。尽管早期死亡率显著降低，但房室瓣（AVV）反流是这些患者心力衰竭的一个关键预测因素。我们试图评估与 SVP 生理相关的 AVV 的生物力学变化。左心室和右心室被缝合到患者来源的 3D 打印支架上，并安装到能够再现 Norwood、Glenn、Fontan 和晚期 Fontan 生理的体外心脏模拟器中。我们发现，与后瓣和隔瓣相比，三尖瓣前瓣的最大力、平均力和最大拉力更高。在不同的生理状态下，Norwood 生理状态下的最大拉力相对于 Glenn、Fontan 和晚期 Fontan 生理状态下的最大拉力更大。这些相反的趋势表明，单心室的 AVV 失效的长期和短期力学机制不同，AVV 干预措施应考虑到瓣叶和生理状态之间的力曲线的不对称性。
