Di Molfetta Arianna, Amodeo Antonio, Fresiello Libera, Trivella Maria Giovanna, Iacobelli Roberta, Pilati Mara, Ferrari Gianfranco
Cardiovascular Engineering Laboratory, Institute of Clinical Physiology-CNR, Rome, Italy.
Department of Pediatric Cardiology and Cardio Surgery, Pediatric Hospital Bambino Gesù, Rome, Italy.
Artif Organs. 2015 Jul;39(7):550-8. doi: 10.1111/aor.12434. Epub 2015 Mar 21.
Considering the lack of donors, ventricular assist devices (VADs) could be an alternative to heart transplantation for failing Fontan patients, in spite of the lack of experience and the complex anatomy and physiopathology of these patients. Considering the high number of variables that play an important role such as type of Fontan failure, type of VAD connection, and setting (right VAD [RVAD], left VAD [LVAD], or biventricular VAD [BIVAD]), a numerical model could be useful to support clinical decisions. The aim of this article is to develop and test a lumped parameter model of the cardiovascular system simulating and comparing the VAD effects on failing Fontan. Hemodynamic and echocardiographic data of 10 Fontan patients were used to simulate the baseline patients' condition using a dedicated lumped parameter model. Starting from the simulated baseline and for each patient, a systolic dysfunction, a diastolic dysfunction, and an increment of the pulmonary vascular resistance were simulated. Then, for each patient and for each pathology, the RVAD, LVAD, and BIVAD implantations were simulated. The model can reproduce patients' baseline well. In the case of systolic dysfunction, the LVAD unloads the single ventricle and increases the cardiac output (CO) (35%) and the arterial systemic pressure (Pas) (25%). With RVAD, a decrement of inferior vena cava pressure (Pvci) (39%) was observed with 34% increment of CO, but an increment of the single ventricle external work (SVEW). With the BIVAD, an increment of Pas (29%) and CO (37%) was observed. In the case of diastolic dysfunction, the LVAD increases CO (42%) and the RVAD decreases the Pvci, while both increase the SVEW. In the case of pulmonary vascular resistance increment, the highest CO (50%) and Pas (28%) increment is obtained with an RVAD with the highest decrement of Pvci (53%) and an increment of the SVEW but with the lowest VAD power consumption. The use of numerical models could be helpful in this innovative field to evaluate the effect of VAD implantation on Fontan patients to support patient and VAD type selection personalizing the assistance.
考虑到供体的短缺，尽管缺乏经验且这些患者的解剖结构和病理生理情况复杂，但心室辅助装置（VAD）对于衰竭的Fontan患者而言可能是心脏移植的一种替代方案。鉴于有大量变量发挥着重要作用，如Fontan衰竭的类型、VAD连接的类型以及设置（右心室辅助装置[RVAD]、左心室辅助装置[LVAD]或双心室辅助装置[BIVAD]），一个数值模型可能有助于支持临床决策。本文的目的是开发并测试一个心血管系统的集总参数模型，以模拟和比较VAD对衰竭的Fontan患者的影响。利用10例Fontan患者的血流动力学和超声心动图数据，使用一个专门的集总参数模型来模拟患者的基线状况。从模拟的基线开始，针对每位患者，模拟了收缩功能障碍、舒张功能障碍以及肺血管阻力的增加。然后，针对每位患者和每种病理情况，模拟了RVAD、LVAD和BIVAD植入。该模型能够很好地重现患者的基线情况。在收缩功能障碍的情况下，LVAD减轻了单心室的负担，并增加了心输出量（CO）（35%）和动脉系统压力（Pas）（25%）。使用RVAD时，观察到下腔静脉压力（Pvci）降低了39%，CO增加了34%，但单心室外部功（SVEW）增加。使用BIVAD时，观察到Pas增加了29%，CO增加了37%。在舒张功能障碍的情况下，LVAD增加了CO（42%），RVAD降低了Pvci，而两者都增加了SVEW。在肺血管阻力增加的情况下，使用RVAD可获得最高的CO增加（50%）和Pas增加（28%），同时Pvci降低最多（53%），SVEW增加，但VAD功耗最低。在这个创新领域，使用数值模型有助于评估VAD植入对Fontan患者的影响，以支持患者和VAD类型的选择，实现个性化的辅助治疗。
