The single ventricular circulation is notable for coexisting systemic venous hypertension and pulmonary arterial hypotension. The use of mechanical circulatory support (MCS) devices is a viable therapeutic treatment option for patients with congestive heart failure. Ventricular assisted devices, cavopulmonary assisted devices, and total artificial heart pumps continue to gain acceptance as viable treatment strategies for single ventricular physiology patients as bridge-to transplantation, bridge-to-recovery, and longer-term circulatory support alternatives. Patients with single ventricular physiology had the lower survival rates compared with those with biventricular circulation. We present a review of the current and future MCS devices for patients with univentricular circulations.
Objective To optimize the hemodynamics of a disk blood pump in children. Method We used the computational fluid dynamics technology to simulate the flow in a pediatric blood pump numerically, and finally analyzed the results for deep study about the thrombosis and hemolysis produced in it, to improve the design according to the results of the flow field analysis. Results We calculated results between the flow rate and the pressure elevation at different rotational speed: 2 500 rpm, 3 000 rpm, and 4 000 rpm, respectively. Under each rotational speed, it was selected five different discharge outlet boundary conditions. The simulation results conformed to the experimental data. The increased pressure of the blood pump was effective. But the phenomenon of flow separation was increased the at blade surface in the low speed region. The maximum wall shear stress was maintained within 100 Pa. Conclusion The design of disc blood pump has a good fluid dynamic performance. And the flow line is fluent, the probability of thrombosis and hemolysis occurred is in the range of control. But the phenomenon of flow separation is appeared. There is a room to improve.
Objective To investigate the relationship of cluster of differentiation 40L (CD40L) between inflammatory response mediated by vascular endothelial injury and Stanford A type aortic dissection (STAAD). Methods In this study from August 2016 to February 2017, a total of 215 blood samples from 95 STAAD patients (67 males and 28 females aged 48.33±12.19 years) and 120 healthy volunteers (94 males and 26 females aged 48.64±10.13 years) were collected. The patients with aortic dissection were taken blood 1 hour before the operation and the healthy volunteers were taken blood from the elbow vein. All STAAD patients were diagnozed by computed tomography angiography (CTA) and patients with Marfan syndrome were excluded. Blood samples were tested by enzyme-linked immunosorbent assay (ELISA) for CD40L, vascular cell adhesion molecule (VCAM-1), E-selectin, interleukin-1 (IL-1) beta, IL-6, tumor necrosis factor-alpha (TNF-α) and so on. ResultsCompared with the healthy population, the level of SCD40L(26.87±5.50 ng/ml vs. 13.39±4.03 ng/ml, P<0.001) in the STAAD patients was significantly higher. E-Selectin (116.62±25.24 ng/ml vs. 77.05±14.30 ng/ml, P<0.001), VCAM-1 (P<0.001), TNF-α (55.35±9.12 ng/ml vs. 37.33±5.61 pg/ml, P<0.001), IL-1β (62.12±13.37 ng/ml vs. 48.68±9.86 pg/ml, P<0.001), IL-6 (499.54±90.45 ng/ml vs. 422.44±34.00 pg/ml, P<0.001) significantly increased. Conclusion The increased expression of SCD40L in STAAD patients and the inflammatory reaction induced by endothelial injury in aortic dissection patients are obvious.
The purpose of this paper is to report the research and design of control system of magnetic coupling centrifugal blood pump in our laboratory, and to briefly describe the structure of the magnetic coupling centrifugal blood pump and principles of the body circulation model. The performance of blood pump is not only related to materials and structure, but also depends on the control algorithm. We studied the algorithm about motor current double-loop control for brushless DC motor. In order to make the algorithm adjust parameter change in different situations, we used the self-tuning fuzzy PI control algorithm and gave the details about how to design fuzzy rules. We mainly used Matlab Simulink to simulate the motor control system to test the performance of algorithm, and briefly introduced how to implement these algorithms in hardware system. Finally, by building the platform and conducting experiments, we proved that self-tuning fuzzy PI control algorithm could greatly improve both dynamic and static performance of blood pump and make the motor speed and the blood pump flow stable and adjustable.