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CARDIOVASCULAR
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Volume 6, 2001, No 1 |
The
Aachen Implantable VAD “VERSUS”: First Animal Studies
F. Förster, H. Reul, G. Rau
Background:
Chronic heart
disease is the leading cause of death in industrialised countries and heart
transplantation is the only long-term therapy for patients with chronic heart
failure. Due to the increasing need of donor hearts and insufficient disposition
of donation, the waiting period for patients to heart transplantation extends up
to one year. For a certain group of patients rest of the native heart could be a
therapy for recovery of their own heart instead of transplantation.
Method:
A displacement
blood pump to support the heart of patients for recovery from end-stage heart
failure has been developed. The design goal was to implant this blood pump
within the hemithorax. For this purpose a novel gear system was developed to
transform the continuous rotation of a synchronous motor into a translatory
pusher plate movement, based on the principle of a swash plate. The result is an
extremely flat titanium capsuled pump unit with a PUR pump chamber.
Results:
The pump unit delivers an output of 1.9 to 3.6 L/min at pump rates between 80
and 140 bpm. Power consumption averages 4.1 W. First animal and cadaver studies
showed very good fitting of the flat pump unit. As a result of these studies,
the connector configuration was optimised for acute animal test and the
implantation of the blood pump in patients was changed from left to right
hemithorax.
Conclusions:
The VERSUS blood pump is suitable for thoracic implantation due to its extremely
flat design. This displacement blood pump displays the common features of a high
efficiency mechanical gear system and a compact design of the pump unit.
(CVE. 2001; 6 (1): 16-20)
Key words: Ventricular Assist Device, electromechanical displacement blood pump, bridge to recovery, spherical gear system, hydrodynamic performance, animal study
Dipl.-Ing.
Frank Förster
Helmholtz-Institute for Biomedical Engineering at the RWTH-Aachen
Pauwelsstr. 20
D-52074 Aachen
Germany
E-mail: foerster@hia.rwth-aachen.de
PABST SCIENCE PUBLISHERS
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