Development of the Valvo Pump: An Axial Flow Pump Implanted at the Heart Valve Position

Mitamura, Yoshinori; Nakamura, Hiroki; Okamoto, Eiji; Yozu, Ryohei; Kawada, Shiaki; Kim, Dong Wook

doi:10.1046/j.1525-1594.1999.06404.x

Cited by 38 publications

(30 citation statements)

References 4 publications

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“…Great efforts have been applied to developing small and relatively easy-to-implant devices for LV assistance (in some cases similar to valve surgery) (79). The experience with the Impella LP (Abiomed, Inc.) has proven that the ease of percutaneous insertion significantly reduces procedural or devicerelated complications such as thrombus or infection (80).…”

Section: Discussionmentioning

confidence: 99%

Mechanical Circulatory Support for Right Heart Failure: Current Technology and Future Outlook

Hsu¹,

Parker

Egger³

et al. 2011

Artificial Organs

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The increasing global prevalence of congestive heart failure is a major healthcare concern, accounting for a high morbidity rate worldwide. In particular, isolated right heart dysfunction after cardiotomy has a poor prognosis and is associated with a high mortality rate. The occurrence of postoperative right heart failure may develop in more than 40% of patients undergoing implantation of a left ventricular assist device (LVAD) and cardiac transplantation. To date, mechanical cardiac assistance in the form of VADs has become accepted as a therapeutic solution for end-stage patients when a donor heart is not available. However, right ventricular (RV) assistance is still in the early phase of development when compared with LVAD technology. State-of-the-art RVADs, both in clinical use and under development, are reviewed in this manuscript. Clinical RVADs include the extracorporeal pulsatile Abiomed BVS 5000 and AB5000, Thoratec PVAD, MEDOS VAD, BerlinHeart Excor, the percutaneous continuous flow CentriMag and TandemHeart systems, and the implantable Thoratec IVAD. Devices on the horizon, including the wear-free implantable DexAide and the minimally invasive Impella RD, are additionally reviewed. In addition to the current status of RV assistance, as well as the device categorization, the outlook and considerations for successful development of future RVADs were discussed.

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Section: Discussionmentioning

confidence: 99%

Mechanical Circulatory Support for Right Heart Failure: Current Technology and Future Outlook

Hsu¹,

Parker

Egger³

et al. 2011

Artificial Organs

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show abstract

“…It is difficult, however, to make the device implantable while being able to meet these requirements. Elsewhere, valvo-pumps with dimensions of 440 mm and 460 mm in outer diameter, respectively, have been reported [8,9]. These are obviously far from being implantable.…”

Section: Methodsmentioning

confidence: 99%

World-smallest LVAD with 27 g weight, 21 mm OD and 5 l min⁻¹flow with 50 mmHg pressure increase

Qian

Wang

Topaz

et al. 2007

Journal of Medical Engineering & Technology

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To investigate the feasibility of a long-term left ventricular assist device (LVAD) placed in the aortic valve annulus, an implantable aortic valve pump (21 mm outer diameter, weighing 27 g) was developed. The device consists of a central rotor and a stator. The rotor assembly incorporates driven magnets and an impeller. The stator assembly has a motor coil with an iron core and outflow guide vanes. The device is to be implanted identically to an aortic valve replacement, occupying no additional anatomic space. The pump delivers the blood directly from left ventricle to the aortic root, like a natural ventricle, therefore causing less physiologic disturbance to the natural circulation. Neither connecting conduits nor 'bypass' circuits are necessary. The pump is designed to cycle between a peak flow and zero net flow to approximate systole and diastole. Bench testing indicates that the pump can produce a blood flow of 5 l min(-1) with 50 mmHg pressure increase at 17,500 rpm. At zero net flow rate, the pump can maintain a diastole aortic pressure against 80 mmHg at the same rotating speed.

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“…1 The position of the seal in our axial pump is shown in Fig. 1, and the schematic structure of the seal is shown in Fig.…”

Section: Structure Of the Magnetic Fluid Sealmentioning

confidence: 99%

Development of an axial flow blood pump: Characteristics of a magnetic fluid seal

2001

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In the development of a rotary blood pump, one of the major problems is thrombus formation near the shaft seal. To solve this problem, a magnetic fluid seal was developed for use in an axial flow pump. A magnetic fluid seal has several advantages, including a high degree of airtightness, no wear or noise, no heat generation, and a simple structure. To determine the reliability of the seal, the sealing pressure, durability, and amount of magnetic fluid mixed with liquids were examined. The seal was composed of two ferromagnetic polepieces and a Nd-Fe-B magnet. The magnetic fluid (LS-40) was injected into the gap between the motor shaft and the polepieces. To minimize leakage of the magnetic fluid, a shield was provided on the polepiece on the liquid side. Sealing pressures at motor speeds up to 10000rpm were measured with the seal immersed in water or bovine blood. The sealing pressures were 195mmHg in water and 173mmHg in blood. The results of magnetic FEM showed that the theoretical sealing pressure was about 230mmHg for motor speeds up to 10000rpm. This result was almost the same as the measured pressure in water. The best result of tests on long-term performance was 691+ days (ongoing) at 8000rpm and 51 days, and 47+ days (ongoing) in a rotating condition. There was only a small amount of magnetic fluid mixed with the liquid. The especially designed magnetic fluid shaft seal is considered to be useful for an axial flow pump.

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Development of the Valvo Pump: An Axial Flow Pump Implanted at the Heart Valve Position

Cited by 38 publications

References 4 publications

Mechanical Circulatory Support for Right Heart Failure: Current Technology and Future Outlook

Mechanical Circulatory Support for Right Heart Failure: Current Technology and Future Outlook

World-smallest LVAD with 27 g weight, 21 mm OD and 5 l min⁻¹flow with 50 mmHg pressure increase

Development of an axial flow blood pump: Characteristics of a magnetic fluid seal

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Development of the Valvo Pump: An Axial Flow Pump Implanted at the Heart Valve Position

Cited by 38 publications

References 4 publications

Mechanical Circulatory Support for Right Heart Failure: Current Technology and Future Outlook

Mechanical Circulatory Support for Right Heart Failure: Current Technology and Future Outlook

World-smallest LVAD with 27 g weight, 21 mm OD and 5 l min−1flow with 50 mmHg pressure increase

Development of an axial flow blood pump: Characteristics of a magnetic fluid seal

Contact Info

Product

Resources

About

World-smallest LVAD with 27 g weight, 21 mm OD and 5 l min⁻¹flow with 50 mmHg pressure increase