GRAVITATIONAL HEART PERFUSION SYSTEMSmdegmbh.eu/.../Isolated_heart_perfusion_systems_ENG_v02.pdfsary, even if you wish to expand the methodological background with the Neely option

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MDE Gesellschaft für medizin-technische und medizin-biologische Produkte mbH

Adress: Altrottstrasse 31, 69190 Walldorf Germany Phone: +49 6227 381 126 • Fax: +49 6227 381 200 • Email: [email protected] • Website: www.mdegmbh.eu

Copyright © 2014 MDE GmbH All Rights Reserved

GRAVITATIONAL HEART PERFUSION SYSTEMS FOR THE LANGENDORFF EXAMINATION OF SMALL MAMMAL HEARTS WITH WORKING HEART OPTION

The advantage of the gravitational product line is that the constant pressure – by the continuous replacement of the saline – can be sustained in a stable way. Another key advantage is that by inserting a proper peristaltic pump, the constant flow mode can be easily configured. The systems are produced in one- and two-channel designs (LS-01G, LS-02G) including the Janicki-type working heart option, by default. Any basic model can be up-graded with the Neely-type working heart option (LF-03GN) without buying any further device. A further key advantage is that the system is supplied with a self-supporting table, which allows an easy placement in the laboratory.

The devices are suitable for isolated mouse, rat, guinea pig and rabbit heart examination

The temperature stability of the system is within 0,1OC, measured directly at the heart connection

The easy placement of the preparation to the heart suspender is provided by the special design

of mobile heart suspending unit and the heart suspending cannula, which both fit to species

The advantage of gravitational design is that the constant flow and constant pressure mode can

be simultaneously achieved

The pressure meter sensors and the drug injec-tion inlet are located directly next to the heart

The systems include the Janicki-type working heart measuring option, by default

We provide an opportunity to stimulate the at-tached dissection (pacing)

The extra-/intracellular MAP measurement is resolved in the systems

Sizes: width: 800 mm, depth: 600 mm, height: 2250 mm




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LS-01G ONE-COLUMN AND LS-02G TWO-COLUMN

LANGENDORFF

The flowchart of the LS-02G two-column system illustrates the operating principle, which is identical with the LS-01G one-column system. The advantage of the LS-02G is that two material impacts can be examined on the preparation simultaneously.

Langedorff heart suspending unit and cannula

We tried to develop a heart suspending unit, where the preparation can be placed on cannula quickly and without damage. The end of the cannula is notched, which sup-ports the method of placement and the positioning of the binding thread. Taking the weight into consideration, the cannula is available in the following sizes: Ø4.5, Ø3.0, Ø2.0 and Ø0.9 mm. One of its biggest advantage is that the measuring points and the material administration are di-rectly above the preparation, which makes dead space minimal.

The optimal temperature (within 0,1OC) is provided by the temperature measurement above the preparation and the autonomous liquid circulation above the heart suspending unit.

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LS-03GN NEELY-TYPE WORKING HEART OPTION

The biggest advantage of the new system is that – unlike any other system on the market- no new device is neces-sary, even if you wish to expand the methodological background with the Neely option.

If you have any pump-controlled Langendorff system (LS-01G, LS-02G) you only need to purchase the Neely option and the heart suspending unit for the methodology.

Langedorff-Neely heart suspending unit and cannula

The Neely option has all the advantages, which we highlighted at the Langendorff heart chamber.

A further advantage is the specially designed arrange-ment of the cannulas, which allows the simultaneous placement of the cannulas into the aorta and the left atrium. Taking the weight into consideration, the can-nulas are available in the following sizes: Ø4.5, Ø3.0, Ø2.0 mm.




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Extra-/intracellular MAP measurement, stimulation

Eight-point extracellular MAP measurement

The system allows one-point extra-/Intracellular MAP measurement and stimulation, built in a 3600 adjustable ball manipulator. The manipulator can be organically connected to the system.

The eight-point non-invasive measurement is a unique development of our company. The preparation is placed in an organ bath filled with saline solution, surrounded by the MAP sensor. The sensors detect the MAP signals through the solution, which are detected by a specially designed biological amplifier.

Saline soultion managing taps Gas-vaporizatio

The taps are essential parts of the system, which lead the saline to the preparation.

For this purpose we designed a multi-position, high-quality and long-wearing tap. The essence of the construc-tion is that the material combi-nation of the tap allows appro-priate grip surface, gapless sealing, and allows smooth closing/opening movement. Moreover, contrary to other systems’ taps, it does not have two positions (open/close), but it closes continuously.

For the appropriate operation of the heart, appropriate quantity and quality carbogen gas is necessary being dissolved in the saline solution.

For the necessary dis-persion we developed a gas vaporizer and fine tuning device. The gas flowing through the re-dactor of the bottle, is collected in a windbag, and through a cylindrical clamp – a tube with appropriate wall thick-ness - the carbogen gas is vaporized into the solution.

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The system

We deliver the system in a complete setup, which contains all the sensors and amplifiers necessary for pressure measurement and the measurement of MAP signals and the programmable isolator square-wave generator for the stimulation of the preparation.

We provide two measurement station for reliable and easy management:

1. Haemodynamic setup with one-point extra-/intracellular MAP measurement:

2pcs pressure measurer with sensors,

1pcs biological amplifier with sensors,

1pc temperature measurer with sensors.

2. Eight-point extracellular MAP measurement:

1pc eight-channel biological amplifiers.

We recommend the following softwares for the visualization, storage and analysis of the curves, which represent the measured physiological parameters:

SPEL Haemosys (MDE Heidelberg),

Power Lab (AD Instruments),

Biopac

Buffer column

Diameter: 56mm Height: 1154mm

Double-walled, thermostated borosilicate glass vessel

Fixed fluid level adjuster with threaded bottom and glass tube

Adjustable carbonizer with vaporizer Buffer drain reservoir

Diameter: 56mm

Height: 160mm

In the thermostating space with two independently built-in spirals

The spiral: with 12 threads, inner diameter 4mm, material: borosilicate glass Heart chamber

Diameter: 80mm

Height: 185mm

Material: borosilicate glass Taps

1 pc two-way filling tap/buffer column 1 pc three-way drain tap

Material: plexi body with Teflon inlay Langendorff frame The frame stands on a table, the top of which is made of stainless steel

The table top has a low edge drip tray and drain pipe

Size of the table top 800mm x 600mm

Height of the table top (from the ground): 750mm

Height of the complete frame (from the ground): 2500 mm

Weight of the frame depending on the configuration (without load): ~60 kg

Gravitational heart perfusion systems




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PUMP-CONTROLLED HEART PERFUSION SYSTEMS FOR THE LANGENDORFF EXAMINATION OF SMALL MAMMAL HEARTS WITH WORKING HEART OPTION

This product line is the latest development of our company, which can be easily placed even in a laboratory with limited place. For the development we used established technical solutions and the experience of the previous years. The systems are made in one- and two-column design (LS-04P, LS-05P) and the Neely-type working heart option (LF-06PN) can be added to any basic setup. The constant pressure and flow rate precision pump is controlled by the amplifier-operated hardware-software unit.

The device can be used for the isolated heart examination of mice,

rats, guinea pigs and rabbits

Measured directly by the connection with the heart,

the temperature stability of the system is within 0,1 C0

The easy attachment of the heart is ensured by the special design of the movable heart

suspending unit and its cannulas

The advantage of pump-control is that constant-flow and constant

pressure mode can be attained by the same device

The sensors of the pressure meter are directly placed by the heart

By default the system includes the Janicki-type balloon working heart option

We provide an opportunity for the stimulation of the preparation

The system solved the measurement of extra-/intracellular MAP

Sizes: width: 800 mm, depth: 600 mm, height: 850mm

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LS-04P ONE-COLUMN AND LS-05P TWO-COLUMN LANGENDORFF

The flowchart of the LS-04P one-column system illustrates the operating principle, which is identical with the LS-05P two-column system. The advantage of the LS-05P is that two material impacts can be examined on the preparation simultaneously.

Langedorff heart suspending unit and cannula

We tried to develop a heart suspending unit, where the preparation can be placed on cannula quickly and without damage. The end of the cannula is notched, which supports the method of placement and the positioning of the binding thread. Taking the weight into consideration, the cannula is available in the following sizes: Ø4.5, Ø3.0, Ø2.0 and Ø0.9mm. One of its biggest advantage is that the measuring points and the material administration are directly above the preparation, which makes dead space minimal.

The optimal temperature (within 0,1OC) is provided by the temperature measurement above the preparation and the autonomous liquid circulation above the heart suspending

unit.




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LS-06PN NEELY-TYPE WORKING HEART OPTION

The biggest advantage of the new system is that – unlike any other system on the market- no new device is neces-sary, even if you wish to expand the methodological background with the Neely option.

If you have any pump-controlled Langendorff system (LS-04P, LS-05P) you only need to purchase the Neely option and the heart suspending unit for the methodology.

Langedorff-Neely heart suspending unit and cannula

The Neely option has all the advantages, which we highlighted at the Langendorff heart chamber.

A further advantage is the specially designed arrangement of the cannulas, which allows the simultaneous placement of the cannulas into the aorta and the left atrium. Taking the weight into consideration, the cannulas are available in the following sizes: Ø4.5, Ø3.0, Ø2.0 mm.

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The system allows one-point extra-/Intracellular MAP measurement and stimulation, built in a 3600

adjustable ball manipulator. The manipulator can be organically connected to the system.

The eight-point non-invasive measurement is a unique development of our company. The prepara-tion is placed in an organ bath filled with saline solu-tion, surrounded by the MAP sensor. The sensors detect the MAP signals through the solution, which are detected by a specially designed biological am-plifier.



For this purpose we designed a multi-position, high-quality and long-wearing tap. The essence of the construction is that the material combination of the tap allows appropriate grip surface, gapless sealing,

and allows smooth closing/opening movement. More-over, contrary to other systems’ taps, it does not have two positions (open/close), but it closes continuously.

For the appropriate operation of the heart, appropri-ate quantity and quality carbogen gas is necessary being dissolved in the saline solution.

For the necessary dispersion we developed a gas vaporizer and fine tuning device. The gas flowing through the redactor of the bottle, is collected in a windbag, and through a cylindri-cal clamp – a tube with appro-priate wall thick-ness - the car-bogen gas is va-porized into the solution.




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The system












Biopac

Buffer column Diameter: 90mm Height: 540mm Double-walled, thermostated borosilicate glass vessel Fixed fluid level adjuster with threaded bottom and glass tube Adjustable carbonizer with vaporizer Heart chamber Diameter: 56mm Height: 160mm In the thermostating space with two independently built-in spirals The spiral: with 12 threads, inner diameter 4mm, material: borosilicate glass Heart chamber Diameter: 80mm Height: 185mm Material: borosilicate glass Taps 1 pc two-way filling tap/buffer column 1 pc three-way drain tap Material: plexi body with Teflon inlay Langendorff frame The frame stands on a table, the top of which is made of stainless steel The table top has a low edge drip tray and drain pipe Size of the table top 800mm x 600mm Height of the table top (from the ground): 100mm Height of the complete frame (from the ground): 1000 mm Weight of the frame depending on the configuration (without load): ~50 kg

Pump-controlled heart perfusion systems

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COMPACT PUMP-CONTROLLED HEART PERFUSION SYSTEM FOR LANGENDORFF EXAMINATION OF SMALL MAMMAL HEARTS WITH WORKING HEART OPTION

The compact pump-controlled heart perfusion system is a closed, integrated system, which is placed in a water circulating, self-thermostating liquid tank. The tank contains two pieces of one liter reservoir with saline, an organ chamber holding the heart preparation and the specially designed, removable heart suspending unit. The technical solution of the water bath makes the system completely independent from the ambient temperature. The system can keep a 0,01OC accuracy, which provides an extremely stable environment for the heart. Another advantage is the removable heart suspending unit, which provides the most optimal suspension for the heart of laboratory ani-mals. The measurement points (BP, temperature, etc.) and the inlet channels are situated above the heart suspend-ing cannula, which increases the accuracy of the measurement. Beside its minimal space requirement the system is suitable to perform constant pressure and flow, as well as Janicki-type working heart measurements. This system is completely unique compared to other devices on the market.

Two independent reservoirs with a total volume of 2 liters

Special removable heart suspending unit

MAP sensors of different sizes for mouse, rat, guinea pig and rabbit heart

An electronically controlled flow speed to ensure the desired constant pressure (0-500 Hgmm)

Parameters to examine: MAP, LVP, perfusion pressure, coronary flow, puffer temperature, heart rate, ECG, surface potential, muscle tone and muscle strength (even with force-displacement technique)

The heart can be externally controlled (pacing), or stimulated

Langendorff and Janicki-type working heart mode

Built-in thermostat

Dimensions: width: 360 mm, depth: 310 mm, height: 360mm




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LS-07C COMPACT LANGENDORFF

The system has to liquid reservoirs. Each reservoir can contain 1000ml saline, which provides a two litre liquid background for the experiment with the continuous rollback. The two reservoirs can be used independently.

In this way the effects of the same compound can be tested in two different doses, or the effect of two different compounds in succession. The substance quantity required for the experiment can be significantly reduced with the small dead volume, which also substantially reduces costs (e.g.: in case of especially expensive or exotic compounds). A tap placed on the closing cap between the columns provide the shift.

PUMP-01 Pump controller unit

It is a basic requirement for the measurements to keep a constant pressure in the system and reduce the resistance of the variable flow and the pulsation of the peristaltic pump to a minimal level.

To maintain the accurate measurement the controller (and through this the pump) is operated by the sign of the pressure sensor, which is placed above the heart suspender cannula. The operation of the controller is presented in the figure below.

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Langendorff heart suspending unit with Janicki-type working heart

The suspension of the heart and the sensor connection is simplified by the fact that the cap with four point leads and spring-load, closing the liquid tank is removable, so the heart suspending unit can be removed from the heart chamber area. The tools necessary for the experiment are fixed to the closing cap:

heart suspender,

stimulator, MAP sensor holder

manipulator,

tap regulating the saline,

balloon catheters of the

Janicki-type working heart unit,

material inlet channel,

temperature sensor,

Bubble trap

We tried to develop a heart suspender, where the dissection can be placed on the heart suspending cannula as quickly as possible, without causing any damage. For this reason the end of the cannula is notched, helping the stability of the placement and the positioning of the binding thread. The cannula is design in the following sizes; Ø4.5, Ø3.0, Ø2.0 and Ø0.9 mm, taking into account the species and its weight. One of the most significant advantages is that the measuring point and the inlet channels are situated directly above the dissection leaving only a minimal dead space.

The cannula built in the ball manipulator is the most significant com-ponent of the Janicki-type working heart unit, since it can be moved vertically and in a 600 angle.




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The system allows one-point extra-/Intracellular MAP measurement and stimulation, built in a 360° adjustable ball manipulator. The manipulator can be organically connected to the system.

The eight-point non-invasive measurement is a unique development of our company. The prepara-tion is placed in an organ bath filled with saline soul-tion, surrounded by the MAP sensor. The sensors detect the MAP signals through the solution, which are detected by a specially designed biological ampli-fier.



For this purpose we designed a multi-position, high-quality and long-wearing tap. The essence of the con-struction is that the material combination of the tap al-lows appropriate grip surface, gapless sealing, and al-lows smooth closing/opening movement. Moreover, contrary to other systems’ taps, it does not have two positions (open/close), but it closes continuously.

For the appropriate operation of the heart, appropriate quantity and quality carbogen gas is necessary being dissolved in the saline solution.

For the necessary dispersion we developed a gas va-porizer and fine tuning device. The gas flowing through the redactor of the bottle, is collected in a windbag, and through a cylindrical clamp – a tube with appropriate wall thickness - the carbogen gas is vaporized into the solution.

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The system












Biopac

Buffer column

2 pcs buffer vessel

Diameter: 65mm

Height: 184mm

Material: borosilicate glass

Adjustable carbonizer with vaporizer

Buffer drain reservoir

The length of the heating spiral in front of the heart suspending unit 72mm and its diameter 14mm

The inner diameter of the spiral, placed in the thermostating space 2mm, with 5 threads

Material: borosilicate glass

Dimensions of the heart chamber

Width: 110mm

Depth: 74mm

Height: 106mm

Taps

1 pc two-way filling tap/buffer column

1 pc three-way drain tap

Material: plexi body with Teflon inlay

Langendorff bath

The system is built-in in a 360mm x 310mm x 360mm plexibath

The cover can be lifted with 160mm to place the heart

The weight of the structure (without load): ~13 kg

Compact pump-controlled heart perfusion systems




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WHAT CAN HEART PERFUSION SYSTEMS HELP WITH?

Types of the system:

Systems developed and distributed by our company provide a wide range for in-vitro heart examination. Our sys-tems can be used for experiments on any laboratory animal without significant alterations. Devices developed by our company can be classified the following way:

Based on physical features: •Gravitational (classic design), •Pump-controlled. Based on methodological features: •Constant pressure and/or fow, •Working heart: •Janicki-type (balloon) •Neely type (retrograde flow).

The essence of the methodology:

Before presenting the technical solution and the unique operation of each device, we represent the essence of the methodology with a brief historical overview.

In case of the standard Langendorff heart the coronary circulator system is perfunded. The empty left ventricle contracts, but it does not pump any liquid. The preparation can be easily altered by installing a second perfusion circle, so the left ventricle can perform pressure work. These type of experiments were first documented by Ridler in 1932, and then by Heubner and Mancke in 1935. The detailed description was published by Neely in 1967. The following picture presents a simple theoretical drawing of the device.

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This simple solution was schematically resolved by the Bardenheuer and Schrader variation (1983), where they lead a balloon into the left ventricle. They do not measure the isovolumetric pressure, instead it pumps the liquid from the balloon into a closed extracorporeal system. Because of the two non-return valves, the liquid can only flow in one direction. Upon every stroke the content of the balloon is squeezed out, which is identical with the stroke volume of the heart. Preload and afterload can be adjusted separately. The flow of the completely separated saline (retrograde in the aorta through the coronaries) is registered quantitatively. In this way the bio-chemical and biophysical circulation of the system can be separately analyzed. This preparation can be useful to examine the pressure-volume work of the heart and the biochemical parameters of the saline in the coronary (e.g.: O2 consumption, metabolism).

A modified Langendorff (Janicki et al. (1974,) Weber and Janicki (1978)) is used for simple hemodynamic-biophysical observations (e.g.: relations of the ventricle pressure-volume), which is similarly to previous descrip-tions utilizes balloon and separated circulation to maintain the coronary perfusion and pressure. In this case the pressure meter is connected to the balloon. The volume of the balloon is measured and regulated through reat-tachable electronics by the sensor.




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Advantages of different systems:

Gravitational systems (LS-01G, LS-02G, LS-03GN)

The systems are manufactured in one- and two-buffer designs. The constant pressure necessary for the operation of the dissection (mouse, rat, guinea pig or rabbit heart) are provided by the liquid column located in the reservoir. The advantage of the two-column design is that is can be used to examine the effects of the same compound in different doses or the effects of two different compounds successively. The liquid level is ensured by the overflow stub of the reservoir and the pump-controlled recirculation of the liquids leaving the dissection. Density and viscosity are provided by the material-combination of the flow-controlling taps, which make any other sealing-compound unnecessary. The design allows a quick and calibrated correction of wearings resulted from the use of the taps. The warmth of the system (0,1OC) is ensured by a high-flow rate transporting, 20 liters volume thermostat (CWB-02). The position-ing of the dissection is provided by an independent mechanism (heart suspension), which is connected to the liquid reservoir through the taps and the spiral heat exchanger. Upon the design of the heart sus-pender, a primary aspect was that the sensors of the continuously monitored parameters (e.g.: pres-sure, temperature) should be placed next to the heart.

We can offer two solutions for the examination of the working heart:

Janicki-type (balloon), which is contained in the basic system setup,

Neely-type (retrograde flow), which can be optionally connected to the Langendorff system.

Pump-controlled systems (LS-04P, LS-05P, LS-06-PN)

The pump-controlled systems have all the positive characteristics that we have mentioned in connection with the gravitational systems. Other advantages over those systems are that they require small space and the same device (pump) can be used for constant pressure and flow. The retrofication of certain components of the gravitational systems resulted in the reduced size of the pump-controlled systems, which increased the stability of liquid-flow, while reducing the consumption of the saline and the

examined compound. Pump-controlled systems are easier to repair and clean.

Compact pump-controlled system (LS-07C)

The compact pump-controlled heart-perfusion system is a closed, integrated system, placed in a water-circulation self-thermostated fluid tank. The tank contains two saline holding reservoirs, an organ cham-ber for the heart dissection and a specially designed, removable heart suspending unit. The water bath solution completely isolates the system from the ambient temperature. The system guarantees a 0,01OC accuracy, which provides an extremely stable environment for the dissection. Another advantage is the removable heart suspending unit, which provides the most optimal suspension solution for laboratory animal hearts. The accuracy is increased by the fact that the measuring points (BP, temperature, etc.) together with the material inlet channel are placed directly by the stump of the organ suspender. With the minimal space requirement, the system is suitable to perform constant pressure and flow, or Janicki-type working heart modes. The quantitative consumption of the saline and the examined agent highly prevails, since shorter internal phases reduce the path of the agent to the examined organ. Further ele-ments (taps, gas vaporizers) have a similar solution to open system. These characteristics make the system completely unique compared to any other systems on the market.

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Electrophysiological measurement options:

To detect the extra- and intracellular MAP sign, we developed constructions, which can be easily adapted to the systems. The electrodes can be easily connected to the mechanical surface of the systems, even posteriorly, and provide a possibility to arrange surface or intracavitary measurements. The eight-point non-invasive extracellular MAP measurement is a unique solution, where the heart in the organ chamber is surrounded by saline. The heart is positioned by the specially designed chamber, which eliminates the negative effects of buoyancy. Further advantage of intra-liquid measurement is that tissue edema can be reduced, since the colloid osmotic pressure is balanced by the hydrostatic pressure of the container. This prolongs the life-expectancy of the dis-section. Furthermore chamber extrasystole can be created by pulse impulses, helping the examination of different anti-arrhythmic agent effects.

Documents

GRAVITATIONAL HEART PERFUSION SYSTEMSmdegmbh.eu/.../Isolated_heart_perfusion_systems_ENG_v02.pdfsary, even if you wish to expand the methodological background with the Neely option