Department of Cardiovascular Surgery, Fukui Cardiovascular Center.
Department of Cardiovascular Surgery, Osaka University Graduate School of Medicine.
Circ J. 2020 Jun 25;84(7):1124-1131. doi: 10.1253/circj.CJ-20-0070. Epub 2020 May 28.
We describe our original left ventricular assist device (LVAD) speed ramp and volume loading test designed to evaluate native heart function under continuous-flow LVAD support.
LVAD speed was decreased in 4 stages from the patient's optimal speed to the minimum setting for each device. Under minimal LVAD support, patients were subjected to saline loading (body weight [kg]×10 mL in 15 min). Echocardiographic and hemodynamic data were obtained at each stage of the LVAD speed ramp and every 3 min during saline loading. Patients were divided into Recovery (with successful LVAD removal; n=8) and Non-recovery (others; n=31) groups. During testing, increased pulmonary capillary wedge pressure caused by volume loading was milder in the Recovery than Non-recovery group (repeated measures analysis of variance; group effect, P=0.0069; time effect, P<0.0001; interaction effect, P=0.0173). Increased cardiac output from volume loading was significantly higher in the Recovery than Non-recovery group (group effect, P=0.0124; time effect, P<0.0001; interaction effect, P=0.0091). Therefore, the Frank-Starling curve of the Recovery group was located upward and to the left of that of the Non-recovery group.
The LVAD speed ramp and volume loading test facilitates the precise evaluation of native heart function during continuous-flow LVAD support.
我们描述了一种原始的左心室辅助装置（LVAD）速度斜坡和容量加载测试，旨在评估连续血流 LVAD 支持下的原生心脏功能。
LVAD 速度从患者的最佳速度以每个装置的最小设置降低 4 个阶段。在最小的 LVAD 支持下，患者接受盐水加载（体重 [kg]×10 mL 在 15 分钟内）。在 LVAD 速度斜坡的每个阶段和盐水加载的每 3 分钟获得超声心动图和血流动力学数据。患者分为恢复组（成功移除 LVAD；n=8）和非恢复组（其他；n=31）。在测试过程中，容量加载引起的肺毛细血管楔压增加在恢复组比非恢复组更温和（重复测量方差分析；组间效应，P=0.0069；时间效应，P<0.0001；交互效应，P=0.0173）。从容量加载中增加的心输出量在恢复组中明显高于非恢复组（组间效应，P=0.0124；时间效应，P<0.0001；交互效应，P=0.0091）。因此，恢复组的 Frank-Starling 曲线位于非恢复组的上方和左侧。
LVAD 速度斜坡和容量加载测试有助于在连续血流 LVAD 支持下精确评估原生心脏功能。
