Twenty-four Hour Left Ventricular BYpass with a Centrifugal Blood Pump

Abstract Purpose Due to the importance of public health and economics, cardiovascular disease has become one of the most important debates and challenges for scientists. However, few studies have been done to address this challenge. The main objective of this document is to provide an optimal model to improve the performance of the left ventricular assist device and reduce costs. In this way, in the present study, the experimental and numerical procedures were developed to analyze the effects of the geometrical features and operational parameters on the performance of a centrifugal blood pump (CBP). Methods In order to achieve this aim, first, experimental tests were carried out to study the influence of the working fluid temperature and the rotational speed on the CBP. Subsequently, the performance of the CBP was assessed using computational fluid dynamics (CFD), and comparison was made against the experimental data. In addition, the influence of mounting an inducer on the overall performance of CBP was also investigated. Results Good agreement between the CFD and the data was obtained. The CFD results showed that increasing the fluid temperature and rotational speed leads to an increase in the hydraulic efficiency, pressure difference, and power. In addition, the reduction of the pressure difference and hydraulic efficiency with increasing the surface roughness was observed. While mounting an inducer on the pump did not significantly impact its overall performance, the highest value of the wall shear stress dropped moderately on the impeller and, therefore, unveiled the possibility of improving the performance of such designs.

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A Compact Centrifugal Blood Pump for Extracorporeal Circulation: Design and Performance

Journal of Biomechanical Engineering ◽

10.1115/1.3138680 ◽

1987 ◽

Vol 109 (3) ◽

pp. 272-278 ◽

Cited By ~ 9

Author(s):

Shinobu Tanaka ◽

Shuzo Yamamoto ◽

Ken-ichi Yamakoshi ◽

Akira Kamiya

Keyword(s):

Thrombus Formation ◽

Animal Experiments ◽

Left Ventricular ◽

Blood Pump ◽

Assisted Circulation ◽

In Vitro Tests ◽

Outer Diameter ◽

Centrifugal Blood Pump ◽

And Performance

A new compact centrifugal blood pump driven by a miniature DC servomotor has been designed for use for short-term extra corporeal and cardiac-assisted circulation. The impeller of the pump was connected directly to the motor by using a simple-gear coupling. The shaft for the impeller was sealed from blood by both a V-ring and a seal bearing. Either pulsatile or nonpusatile flow was produced by controlling the current supply to the motor. The pump characteristics and the degree of hemolysis were evaluated with regard to the configuration of the impeller with a 38-mm outer diameter in vitro tests; the impeller having the blade angles at the inlet of 20 deg and at the outlet of 50 deg was the most appropriate as a blood pump. The performance in an operation, hemolysis and thrombus formation in the pump were assessed by a left ventricular bypass experiment in dogs. It was suggested by this study that this prototype pump appears promising for use not only in animal experiments but also in clinical application.

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Estimation of Left Ventricular Recovery Level Based on the Motor Current Waveform Analysis on Circulatory Support with Centrifugal Blood Pump

Artificial Organs ◽

10.1046/j.1525-1594.2001.06862.x ◽

2001 ◽

Vol 25 (9) ◽

pp. 713-718 ◽

Cited By ~ 10

Author(s):

K. Takahashi ◽

M. Uemura ◽

N. Watanabe ◽

K. Ohuchi ◽

M. Nakamura ◽

...

Keyword(s):

Left Ventricular ◽

Waveform Analysis ◽

Blood Pump ◽

Circulatory Support ◽

Current Waveform ◽

Centrifugal Blood Pump ◽

Motor Current ◽

Left Ventricular Recovery

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A Pivot Bearing-Supported Centrifugal Pump for a Long-Term Assist Heart

The International Journal of Artificial Organs ◽

10.1177/039139889702000407 ◽

1997 ◽

Vol 20 (4) ◽

pp. 222-228 ◽

Cited By ~ 3

Author(s):

T. Nakazawa ◽

Y. Ohara ◽

R. Benkowski ◽

K. Makinouchi ◽

Y. Takami ◽

...

Keyword(s):

Cardiopulmonary Bypass ◽

Centrifugal Pump ◽

Thrombus Formation ◽

Left Ventricular ◽

Production Model ◽

Blood Pump ◽

Preliminary Evaluation ◽

Centrifugal Blood Pump ◽

Normal Ranges ◽

Pivot Bearing

A pivot bearing-supported centrifugal blood pump has been developed. It is a compact, cost effective, and anti-thrombogenic pump with anatomical compatibility. A preliminary evaluation of five paracorporeal left ventricular assist studies were performed on pre-conditioned bovine (70-100 kg), without cardiopulmonary bypass and aortic cross-clamping. The inflow cannula was inserted into the left ventricle (LV) through the apex and the outflow cannula affixed with a Dacron vascular graft was anastomosed to the descending aorta. All pumps demonstrated trouble free performance over a two-week screening period. Among these five studies, three implantations were subjected for one month system validation studies. All the devices were trouble free for longer than 1 month. (35, 34, and 31 days). After achieving one month studies, all experiments were terminated. There was no evidence of device induced thrombus formation inside the pump. The plasma free hemoglobin levels were within normal ranges throughout all experiments. As a consequence of these studies, a mass production model C1E3 of this pump was fabricated as a short-term assist pump. This pump has a Normalized Index of Hemolysis of 0.0007 mg/100L and the estimated wear life of the impeller bearings is longer than 8 years. The C1E3 will meet the clinical requirements as a cardiopulmonary bypass pump. For the next step, a miniaturized pivot bearing centrifugal blood pump PI-601 has been developed for use as a permanently implantable device after design optimization. The evolution from C1E3 to the PI-601 converts this pivot bearing centrifugal pump as a totally implantable centrifugal pump. A pivot bearing centrifugal pump will become an ideal assist pump for the patients with failing heart.

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