Scientific exhibition

1. Totally Implantable Left Ventricular Assist System (Baxter Healthcare Corp., Novacor Division)

Baxter's Novacor Division is the first company that received Food and Drug Administration (FDA) approval for the clinical implantation of its totally implantable left ventricular assist systems (LV AS). Novacor's totally

implantable systems will be clinically evaluated at St. Louis University and University of Pittsburgh. The clinical studies at the two institutions are going to start in late 1991 to early 1992.

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2. Symbion Ventricular Assist Device (VAD)/Total Artificial Heart (T AH) (Goodman Co., Ltd.)

Circulatory support system. a Console I>

b Total artificial heart (TAH)

c Ventricular assist device (VAD)

3. Motor-driven Artificial Heart (Hiroshima University)

Toward a totally implantable artificial cardiac prosthesis, various kinds of motor-driven artificial heart have been made and tested at Hiroshima University since 1968. An ultrasonic-motored artificial heart and a pendulum swing artificial heart were presented at the Scientific Exhibition at the 3rd International Symposium on Artificial Heart and Assist Device. Further studies are now being undertaken.

b The main parts of the ultrasonic-motored artificial heart. From upper left, clockwise: ultrasonic motor of 100rpm and 37N. cm, two casings, two pushing pistons, two blood chambers of polyurethane with heart valves, crank chain members, crank casing, motor attachment plate, pins, and screws. Now, we are looking for a more power­ful motor of rating torque above 80 N . cm at a speed of around 120rpm, as an ultrasonic motor

c The main parts of the pendulum-swing artificial heart.

a Pendulum swing artificial heart (left) and ultrasonic­motored artificial heart (right). The pendulum swing artificial heart of 64-ml stroke volume worked at flow rate of 1.6-6.0Ilmin with a driving rate of 40-125 beats/min in a mock test. The ultrasonic-motored artificial heart of 51 ml worked well in a mock test, but an in vivo experiment showed the shortage of output torque of the ultrasonic motor, commercially available now in Japan, resulting in excessive temperature rise of the ultrasonic motor itself

From upper left, clockwise: brush less d.c. motor of I> 3000rpm and ION. cm, motor mounting plate, two side plates, two pushing plates with rounded surfaces, two lenticular blood chambers of polyurethane with heart valves, screws, link members, a set of reduction gears, and bearings. These now are also under improvement

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4. Development of a Totally Implantable Electric Assist Pump System (Hokkaido University and Hokkaido Tokai University)

The system consists of a motor-driven assist pump and a transcutaneous energy transmission unit involving an optical telemetry system. The assist pump actuator consists of a brush less d.c. motor and a specially designed miniature ball-screw.

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A Totally implantable electric assist pump system. a, External batteries; b, energy transmitter; c, transcutaneous energy transformer; d, energy receiver; e, internal battery; f, controller; g, electric assist pump; h, compliance chamber. B Motor-driven assist pump and compliance chamber. The assist pump measures 312 ml and weighs 790 g. Stroke volume is 60 ml. C Specially designed minia­ture ball-screw. The outer diameter of the ball-screw nut is

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20ml, and length of the threaded shaft 40mm. It weighs 52 g. D Pump stroke sensor and its electronics. The Hall­effect sensor (arrows) detects the position of the pusher plate. Pump stroke is monitored based on pusher-plate displacement. E Structure of magnetic coupling. Active pump filling is enabled by magnetic force between a rubbery magnet (a) and an iron plate (b) attached to the blood pump

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5. Philadelphia Heart System (Cardiac Systems, Japan Medical Supply)

Philadelphia Heart System is a drive console of pneumatic controllers for use with the total artificial heart and with blood pumps.

b Philadrive IP, one of the pneumatic controllers of the Philadelphia Heart System

c Philadelphia Hearts. Blood pumps are vacuum-formed ventricles with continuous intima and blood diaphragm

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a Heart-Cart, Modell. The clinical drive console houses two pneu­matic controllers, an air com­pressor, and back-up air tanks, for use with total artificial hearts

6. Hemopump (Temporary Cardiac Assist System) (Johnson & Johnson Interventional Systems)

The pump and cannula are inserted through the femoral artery and placed in the aorta and left ventricle. The spiral vanes of the pump are rotated by a motor outside of the patient's body via a thin wire (cable). Blood is sucked from the tip of the cannula, in the left ventricle, and flows into the aorta through the other end of the cannula.

b Insert pump assembly through the femoral artery

c The cannula and pump placed in left ven­tricle and aorta 'il

7. Artificial Heart Using a Linear Pulse Motor (H. Yamada, Shinshu University)

The artificial heart (AH-S90) using a linear pulse motor was developed by the Shinshu University group which con­sists of universities, manufacturing companies, and hos-

a Artificial heart (AH-S90) using a linear pulse motor. (Plate size is 30 x 100 [mm])

a Hemopump console

d The pump within the cannula

pitals . The artificial heart (AH-S90) could achieve 5.3 liters per minute at the pulse rate of 100 beats per minute in the overflow type mock test device.

b Mock circulatory system of the artificial heart (AH-S90)

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8. An Australian-made Ventricular Assist Device - The Spiral Vortex Pump (St. Vincent's Hospital, Sydney, Australia)

A new ventricular assist device (VAD) has been developed that relies on laminar, continuous flow patterns to reduce the potential for thrombosis and hemolysis. The success of the design has been demonstrated using in vitro and in vivo test methods.

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e In vitro comparison of hemolysis between two V AD models, showing superior biocompatibility of Spiral Vortex type. HCT, hematocrit; BPM, beats per minute

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f Sheep implanted with Spiral Vortex VAD; 20 days after the operation

9. Tohoku University TH-7B pneumatically driven sac-type ventricular assist device system and newly developed vibrating electromagnetic pump (Department of Medical Engineering and Cardiology, Research Institute for Chest Diseases and Cancer; and Department of Thoracic and Cardiovascular Surgery, School of Medicine; and Department of Electrical Engineering and Department of Electrical Communications, Faculty of Engineering; and The Institute of High-Speed Mechanics, Tohoku University)

Tohoku University has been involved continuously in artificial heart research for over 20 years. Following extensive preclinical evaluation of our ventricular assist device (V AD) system, clinical trials were initiated in Tohoku University and additional institutes.

Recently, we developed this vibrating electromagnetic pump for the totally implantable artificial heart.

a TH-7B pneumatically driven sac-type ventricular assist b Pneumatic drive console for clinical use device, connectors with ball valve, and inflow and outflow cannulae with ultrasonic flow probe

c A cross-sectional schematic illustration (upper) and a photograph (lower) of an implantable vibrating electromagnetic pump for output of II/min

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10. Heart-lung System, COMPO TM: A Pulsatile Pump (Tonokura Ika Kogyo Co., Ltd.)

The Tow Nok heart-lung machine, COMPO, satisfies all the design criteria: compact size, superior performance, and versatility. It provides maximum space utility in the operating room for open-heart surgery. Component design makes this a desirable pump and accessory configuration to meet the needs of ever-demanding advanced open-heart surgery.

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a Compact size, superior per­formance, versatile pump layout and accessories

b Unique patented n-shaped pump casing. The pump creates the minimum reverse blood flow by gradual take­off from the pump casing

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c Displays all vital information on the patient and pump operation

11. Ventricular Assist System (National Cardiovascular Center and Toyobo Co., Ltd.)

The Toyobo Ventricular Assist System for temporary use has been developed under the leadership of The National Cardiovascular Center in Japan.

The blood pump is fabricated from newly developed medical-grade polyether polyurethane ureas, the Toyobo TM­Series and blood-contacting surface is made with excellently antithrombogenic material: Toyobo TM-3.

As a control drive console for the blood pump, Toyobo has introduced models VCT-IOO and VCT-20. Both of them can maintain left atrial pressure and total flow (cardiac output + bypass flow) automatically within their preset ranges simultaneously by changing the %-Systole (pumping duration in one cardiac cycle).

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b Control drive console VCT-20 for mono-ventricular assist

a Control drive console VCT-IOO which can drive two pumps simultaneously

c Air-driven diaphragm-type blood pump: left L (adult) size; right S (infant) size

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12. Tele-monitoring and Tele-controlling System of Artificial Heart Through Wireless Video Network and Telephone Line (University of Tokyo; Nippon Zeon Co., Ltd.; Aisin Seiki Co., Ltd.)

This is a demonstration of a future telecare system for artificial heart (AH) patients. The University of Tokyo and Keidanren Kaikan (about 6km apart) were connected by a wireless video network (Pasolink) relaying via Tokyo Denki University. The AH goat, pump movement, and driving parameter values could be monitored through television. The TV camera could be switched to an alternative one and driving parameters could be changed through a pair of microcomputers connected by a telephone line at both ends.

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b Whole view of the exhibition booth. The left side is a television for monitoring and a microcomputer for te1e­control. The right side shows T AH, left ventricular assist device (LVAD), and the jellyfish valve

a Schema of tele-monitoring and controlling system of total artificial heart (T AH) implanted in a goat

d The flow rate of a blood pump at the University of Tokyo could be controlled from Keidanren Kaikan through a telephone line, and its movement and flow rate value could be monitored on the TV

13. An Electrohydraulic Total Artificial Heart and Components Under Development (Artificial Heart Research Laboratory, University of Utah)

An electrohydraulic total artificial heart (EHT AH) and its various components are shown. The key features of this device are the Inter-Atrial Shunt (lAS) between the two atrial cuffs as a way to achieve balance; dual energy converters, each of which utilizes an axial flow pump and a 3-phase brushless d.c. motor; and miniaturized electronics. The device shown has been tested in both in-vitro and acute in-vivo experiments.

a Instrumented lAS with modular system used for in-vitro and acute in-vivo tests

e Model of future EHT AH configuration

b EHT AH energy converter showing internal components

.... c EHT AH system on the mock circulation with electronics and controller

d Size reduction of electronics obtained by miniaturization with very large scale integrated circuits (VLSI)

COMP ARA TIVE SIZE OF "DlSCRE.TE" VS "VLSI"

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Key Word Index

Absorbed protein 57 Anticoagulant 31 Artificial atrial septal defect 235 -heart 101,117,131,137,167,173,

197,205,293 Assisted circulation 167, 329 Australian results 257 Auto-regulation 173 Axial flow pump 117

Biocompatibility 69 Biomaterial 45, 147 Biostability 77 Biventricular assist device (BVAD)

315 - bypass 323 Blood compatibility 11, 31 - pump 137 Body-weight mismatch 285 Bridge to transplantation 293, 323

Cannula 107 Cardiac assist device 183 - rejection 249 - transplantation 257 Cell activation 45 - adhesion 45 - membrane 39 Chronic animal experiment 215 Circulatory support 263, 323 - - device 303 Clinical evaluation plans 3 Compliance chamber 137 Control algorithm 173 - mode of TAH 147 Crystalline-amorphous microstructure

23 Cytoplasmic free calcium level 23

Design of blood pumps 215 Dimensional criteria 215 Driving mechanism 137 Dye washout test 107 Dynamic balance 235

Electric motor 183, 205 Electrical artificial heart 235 Experimental model 221

Fabricated device 69

Goat 221 Graft failure 275 Growth factors 45

Heart failure 275 - transplantation 167, 249, 269, 275 Hemodynamic instability 263 Hemolysis 93, 107 Heparin graft copolymer 11 - immobilized surface 11 Heterotopic heart transplantation

285 Human chest cage 229 Hydrolytic degradation 77 Hydrophilic spacer 11 Hydrophilic-hydrophobic block

copolymer 39

Immunoperoxidase method 57 Immunosuppression 249 Immunosuppressive therapy 263 Implantable device 167 - driver 131 - total artificial heart 221 Indications 303 Interatrial shunt 235 Intrathoracic pressure influence on

stroke volume 235

Jarvik 303

Left ventricular assist device (LV AD) 147,249,315

- - bypass 323 Lenticular blood chamber 131 Linear actuator 101 - pulse motor 101 Link motion 131 Lipid sorption 77 Lung transplant 269

Mechanical circulatory assistance 275

Micropatterning 69 Microprocessor 183 Mitral regurgitation 329 Mock circulatory testing 101 Monocytes 45 Monoventricularization 329 Motor-driven assist pump 197

Moving actuator 229 Multiple regression analysis 189 Muscle damage 93 - powered cardiac assist device 123 Myocardial infarction 329 - protection 249

Neurogram 189 Nonpulsatile blood pump 117 - pump 147, 167 Nontechnological issues 3 Nonthrombogenicity 23 Novacor LV AS 303 Nutation 93

Optical rotary encoder 183 Organ preservation 269 Orthotopic 257 - heart transplantation 285 - transplantation 263 Oxidation 77

Pendulum swing driver 131 - type pump 229 Permanent 205 - magnet 137 Photochemistry 69 Platelet activation 23, 39 - adhesion 31 Postcardiotomy shock 315 Power output 123 Pre transplant assessment 263 - support 293 Prospective control 189 Prosthetic ventricles 293 Protein adsorption 45 Pulmonary hypertension 285 - vascular resistance 263 Pusher-plate-type blood pump 183

Rejection 263 Renal sympathetic nerve activity 189 Review article 235 Right ventricular function 309 - - support 123 Right-left ventricular balance 235

Scanning electron microscope 57 Segmented polyurethane 77 Skeletal muscle ventricle 123

351

352

Sodium vinyl sulfonate 31 Spiral Vortex pump 107 Stroke work 123 Superoxide anion 45 Surface processing 69 - structure 39 Symbion BIV AD 303

Teaspoon pump 93 Tether-free 229 Thrombin inhibitor 31

Tomasu Heart 221 Total artificial heart (TAH) 3, 147,

189,215 Totally implantable system 87 --TAH 147 Transcutaneous electric transmission

87 - energy transmission system 197 Transmission electron microscope 57

Univalved artificial 87

Key Word Index

Univentricular bridge to transplant 309

Utah-lOO total artificial heart 57

Validation 3 Valvular heart disease 315 Ventricular assist 3 - - device 107, 197,293,323 -- pumps 275 - septal perforation 329 Vibrating flow 87