Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.
R1 Engineering, Euclid, OH, USA.
Int J Artif Organs. 2021 Jul;44(7):465-470. doi: 10.1177/0391398820977508. Epub 2020 Dec 1.
We are developing a new left atrial assist device (LAAD) for patients who have heart failure with preserved ejection fraction (HFpEF). This study aimed to assess the hemodynamic effects of the LAAD under both normal heart conditions and various diastolic heart failure (DHF) conditions using a mock circulatory loop. A continuous-flow pump that simulates LAAD, was placed between the left atrial (LA) reservoir and a pneumatic ventricle that simulated a native left ventricle on a pulsatile mock loop. Normal heart (NH) and mild, moderate, and severe DHF conditions were simulated by adjusting the diastolic drive pressures of the pneumatic ventricle. With the LAAD running at 3200 rpm, data were collected at 60, 80, and 120 bpm of the pneumatic ventricle. Cardiac output (CO), mean aortic pressure (AoP), and mean LA pressure (LAP) were compared to evaluate the LAAD performance. With LAAD support, the CO and AoP rose to a sufficient level at all heart rates and DHF conditions (CO; 3.4-3.8 L/min, AoP; 90-105 mm Hg). Each difference in the CO and the AoP among various heart rates was minuscule compared with non-pump support. The LAP decreased from 21-23 to 17-19 mm Hg in all DHF conditions (difference not significant). Furthermore, hemodynamic parameters improved for all DHF conditions, independent of heart rate. The LAAD can provide adequate flow to maintain the circulation status at various heart rates in an in vitro mock circulatory loop.
我们正在为射血分数保留的心力衰竭（HFpEF）患者开发一种新型左心房辅助装置（LAAD）。本研究旨在使用模拟循环回路评估 LAAD 在正常心脏和各种舒张性心力衰竭（DHF）条件下的血液动力学效应。一个模拟 LAAD 的连续流泵被放置在左心房（LA）储液器和模拟天然左心室的气动心室之间，在脉动模拟循环上运行。通过调整气动心室的舒张驱动压力来模拟正常心脏（NH）和轻度、中度和重度 DHF 条件。当 LAAD 以 3200 rpm 运行时，在气动心室的 60、80 和 120 bpm 时收集数据。比较心输出量（CO）、平均主动脉压（AoP）和平均 LA 压（LAP），以评估 LAAD 性能。在 LAAD 支持下，CO 和 AoP 在所有心率和 DHF 条件下都升高到足够的水平（CO；3.4-3.8 L/min，AoP；90-105 mmHg）。与无泵支持相比，各种心率之间 CO 和 AoP 的差异微不足道。在所有 DHF 条件下，LAP 从 21-23 降至 17-19 mmHg（差异无统计学意义）。此外，LAAD 可在各种心率下提供足够的流量，以维持体外模拟循环回路中的循环状态。
