Durham Lucian A, Dearani Joseph A, Burkhart Harold M, Joyce Lyle D, Cetta Frank, Cabalka Allison K, Phillips Sabrina D, Sundareswaran Kartik, Farrar David, Park Soon J
Division of Cardiovascular Surgery, The Mayo Clinic, Rochester, MN, USA.
World J Pediatr Congenit Heart Surg. 2011 Apr;2(2):243-8. doi: 10.1177/2150135110397386.
Although the Fontan procedure has been enormously successful in palliation of single-ventricle patients, many seem to experience progressive failure of the Fontan circulation over time. Ventricular assist devices (VADs) have developed into stable platforms for long-term support of adult patients with heart failure. Given the success of axial flow devices, it was hypothesized that the technology could provide clinical benefit to failing Fontan patients. The aim of this study was to use a computer model to evaluate VAD support in failing Fontan physiology. A computer model of Fontan circulation with heart failure was developed and the HeartMate II (HM II) (Thoratec Corp) axial flow ventricular assist device was connected to this model in a systemic configuration to examine its impact. Cardiac catheterization data from 7 patients (8 catheterization studies) with failing Fontan physiology were applied to this model to evaluate the impact of using the HM II in this manner. When the HM II was used in a systemic configuration at 8000 rpm, there was a 35% decrease in the systemic venous pressure in the Fontan circuit and a 63% decrease in pulmonary capillary wedge pressure with a resultant 41% increase in CI. The model also predicted patient-specific parameters where the VAD may not benefit the patient, such as fixed elevated pulmonary vascular resistance, low systemic ventricular end-diastolic pressure, and high unresponsive systemic vascular resistance. These data suggest a potential benefit from application of axial flow VAD technology in the management of failing Fontan physiology. Clinical correlation will allow for refinement of this model as a predictive tool in discerning which patients may benefit from placement of a VAD and what issues must be addressed prior to implanting the device.
尽管Fontan手术在单心室患者的姑息治疗方面取得了巨大成功，但随着时间的推移，许多患者似乎都经历了Fontan循环的渐进性衰竭。心室辅助装置（VAD）已发展成为心力衰竭成年患者长期支持的稳定平台。鉴于轴流装置的成功，有人推测该技术可为衰竭的Fontan患者带来临床益处。本研究的目的是使用计算机模型评估VAD对衰竭的Fontan生理状态的支持作用。建立了一个伴有心力衰竭的Fontan循环计算机模型，并将HeartMate II（HM II）（Thoratec公司）轴流心室辅助装置以全身配置连接到该模型上，以检查其影响。将7例伴有衰竭Fontan生理状态患者（8次心导管检查研究）的心导管检查数据应用于该模型，以评估以这种方式使用HM II的影响。当以8000转/分钟的全身配置使用HM II时，Fontan循环中的全身静脉压降低了35%，肺毛细血管楔压降低了63%，心指数（CI）相应增加了41%。该模型还预测了VAD可能对患者无益处的特定患者参数，如固定升高的肺血管阻力、低全身心室舒张末期压力和高无反应性全身血管阻力。这些数据表明，轴流VAD技术在衰竭的Fontan生理状态管理中具有潜在益处。临床相关性将有助于完善该模型，使其成为一种预测工具，用于识别哪些患者可能从VAD植入中获益以及在植入该装置之前必须解决哪些问题。
