US3587567A - Mechanical ventricular assistance assembly - Google Patents

Abstract

A MECHANICAL VENTRICULAR ASSISTANCE APPARATUS COMPRISED PRIMARILY OF A VENTRICULAR ASSISTOR CUP HAVING A CONFIGURATION GENERALLY CONFORMING TO THE SURFACE CONFIGURATION OF THE VENTRICLES OF THE HEART. THE CUP IS FORMED OF A RIGID OR NONRESILIENT MATERIAL AND INCLUDES A FLEXIBLE LINER OR DIAPHRAGM. THE RIGID OUTER SHELL IS PROVIDED WITH AN OPEN END FOR RECEIVING THE VENTRICLES AND FIRST AND SECOND PORTS FOR SELECTIVE COUPLING TO PRESSURE OR VACUUM SYSTEMS. THE DIAPHRAGM IS SECURED ABOUT THE OPEN END AND IS FURTHER SECURED ADJACENT ONE OF THE TWO PORTS. AT LEAST ONE ELECTRODE IS PROVIDED IN THE REGION OF ONE OF SAID PORTS FOR THE APPLICATION OF SIGNALS TO CARRY OUT FIBRILLATION OR DEFRIBILLATION OF THE HEART. IN THE CASE WHERE IT IS DESIRED TO PROVIDE MECHANICAL ASSISTANCE OF THE HEART PUMPING ACTION IN SYNCHRONISM WITH NORMAL HEART RHYTHM THE ELECTRODE MAY BE EMPLOYED FOR MONITORING THE ELECTROCARDIAC SIGNALS AND HENCE FOR OPERATING THE MECHANICAL PUMPING ACTION IN SYNCHRONISM WITH THE NORMAL HEART RHYTHM. ALTERNATIVELY ADDITIONAL ELECTRODES MAY BE MOUNTED WITHIN THE ASSEMBLY FOR PERFORMING FIBRILLATION AND DEFIBRILLATION FUNCTIONS WHICH ELECTRODES ARE POSITIONED A SPACED DISTANCE AWAY FROM SAID FIRST MENTIONED ELECTRODE AND ALONG SAID DIAPHRAGM.

Description

United States Patent Peter Paul Schiff 5812 Morris St., Philadelphia, Pa. 19144 [2]] App], No. 785,652

[22] Filed Dec. 20, 1968 [45] Patented June 28, 1971 [72] Inventor [54] MECHANICAL VENTRICULAR ASSISTANCE Primary Examiner L. W. Trapp Attorney-Ostrolenk, Faber, Gerb and Soffen ABSTRACT: A mechanical ventricular assistance apparatus comprised primarily ofa ventricular as'sistor cup having a configuration generally conforming to the surface configuration of the ventricles of the heart, The cup is formed of a rigid or nonresilient material and includes a flexible liner or diaphragm. The rigid outer shell is provided with an open end for receiving the ventricles and first and second ports for selective coupling to pressure or vacuum systems. The diaphragm is secured about the open end and is further secured adjacent one of the two ports. At least one electrode is provided in the region of one of said ports for the application of signals to carry out fibrillation or defibrillation of the heart. In the case where it is desired to provide mechanical assistance of the heart pumping action in synchronism with normal heart rhythm the electrode may be employed for monitoring the electrocardiac signals and hence for operating the mechanical pumping action in synchronism with the normal heart rhythm.

Alternatively additional electrodes may be mounted within the assembly for performing fibrillation and defibrillation functions which electrodes are positioned a spaced distance away from said first mentioned electrode and along said diaphragm.

PATENIEUJUH28 lsn SHEET 1 BF 2 MECHANICAL VENTRICULAR ASSISTANCE ASSEMBLY The present invention relates to mechanical systems for assisting in the pumping operation of a heart and more particularly to a mechanical ventricular assistance assembly capable of monitoring, fibrillating and defibrillating the heart.

Mechanical ventricular assistance may be defined as a mechanical support of the body circulatory function through mechanically assisting the ventricles of the heart. The ventricles, which are located below the atria or upper chambers of the heart, are responsible for almost all of the pumping action of the heart.

The two types of possible assistance which the system of the present invention may provide are nonsynchronized assistance and synchronized assistance respectively. In the case of nonsynchronized assistance the actual pumping action of the heart muscles is stopped by fibrillation of the heart. One suitable means of fibrillating the heart is through the application of a small alternating voltage which is applied across the heart at two arbitrarily selected locations. This causes the natural electrochemical stimulation of the heart to become depolarized causing the heart to fibrillate or experience a slight twitching action with no orientation or pumping action per se. The application of the ventricular cup and mechanical ventricular assistance is then initiated with no interference or bucking of the natural rhythm of the heart due to the fact that the heart is not beating in its normal fashion.

In the case of synchronous assistance, the pumping action of the ventricular cup is synchronized in accordance with the natural electrocardiac signal generated by the heart. Through the application of appropriate delays the natural pumping action of the heart may thus be strengthened or assisted. In order to perform these functions, it is most desirable to provide appropriate electrical contact with the heart in order to produce fibrillation in the case where nonsynchronous assistance is desired or alternatively to monitor the electrocardiac signal in the case where synchronous operation of the ventricular assistance system is desired.

At the termination of the period of mechanical ventricular assistance of a fibrillating heart, it is important to defibrillate the heart which consists of polarizing the heart with a pulse of high voltage (generally direct current) applied to two points across the heart, which points lie on opposite sides of the central axis of the heart. This voltage defibrillates the heart and restores the natural pumping action.

All of these operations may be provided for (in a selective fashion) through the use of a ventricular cup having electrodes positioned within the cup in such a manner as to effectively monitor electrocardiac signals and generate either fibrillation or defibrillation. The electrodes are found to make good electrical contact with the heart, to provide good strong signals and to yield an apparatus which is simple both in application to the heart and in use.

It is therefore one object of the present invention to provide a novel ventricular cup assembly for providing mechanical ventricular assistance to a heart which assembly includes electrodes for monitoring electrocardiac signals and for producing fibrillation and defibrillation.

Still another object of the present invention is to provide a novel ventricular cup assembly for use in mechanical ventricular assistance of the heart to maintain pumping action and thereby sustain the operation of the heart, which cup assembly is provided with at least one electrode arranged to make physical and electrical contact with the heart for the purpose of selectively causing either fibrillation or defibrillation of the heart or selectively monitoring electrocardiac signals in order to provide synchronous pumping assistance or pacing of the heart.

These as well as other objects of the present invention will become apparent when reading the accompanying description and drawings in which:

FIG. I shows a sectional view of a conventional ventricular assistance cup.

FIG. 2 shows a ventricular assistor pump system which may employ the ventricular assistance cup of FIG. I.

FIG. 3 is a sectional view of a ventricular assistance cup of the present invention including electrodes for selectively monitoring electrocardiac signals and for applying fibrillation and defibrillation signals to the heart.

FIG. 1 shows a conventional ventricularassistor cup assembly 10 which is comprised of a rigidouter shell 11 having a shape substantially conforming to the surface configuration of the heart ventricles. A flexible liner or diaphragm I2 is positioned within thecup 11 and is provided with a substantially annularshaped lip 13 extending toward the central axis of cup l 1. The liner is attached to the rigid cup at its upper end and at its lower end by a suitable epoxy, for example, as shown at 14 and 15 respectively. The cup is provided with atube 16 communicating with an opening 17 provided at the apex of the cup for introducing a continuous or sustained negative pressure to the ventricles for a purpose to be more fully described. The cup is further provided with a secondtubular portion 18 communicating with anopening 19 in the cup for applying a pulsating positive and negative pressure.

The design of the cup is such that the ventricles of the heart (designated RV and LV respectively) fit within the cup in the manner shown in FIG. I. The sustained negative pressure applied throughtube 16 retains the ventricles within the cup. The pulsatile (i.e. alternating positive and negative) pressure is applied through thepulsed pressure line 18 for the purpose of inducing the pumping action. The positive and negative pulsatile modes which are referred to as the systolic and diastolic modes, respectively, cause the alternating contraction and relaxation of the flexibleresilient diaphragm 12. For example, as shown in FIG. 1, the application of positive pressure topressure line 18 causes theflexible diaphragm 12 to move from the relaxed (solid line) position to thephantom line position 12 thereby contracting the ventricles of the heart therebetween. The alternating negative pressure applied toline 18 causes the abrupt return of the diaphragm to thesolid line position 12.

' A system for providing the pulsatile operations is shown best in FIG. 2. Thissystem 20 includes a pulsatile pressure system which is composed of a systolic or positivepressure air supply 21 and diastolic or negativepressure air supply 22.Source 21 is coupled throughpressure regulator 23,reservoir 25,solenoid valve 27 and dampeningvalve 29 to acommon conduit 31 which in turn is coupled to thepulsed pressure line 18 of theventricular assistor cup 10. In a like manner thenegative pressure source 22 is coupled through avacuum regulator 24,reservoir 26,solenoid valve 28 and dampeningvalve 30 to thecommon conduit 31 so as to selectively apply negative pressure pulses to theassistor cup diaphragm 12, (shown best in FIG. 1).

Thepressure regulator 23 andvacuum regulator 24 are each adjustable to provide the necessary pressure and vacuum levels. Theair reservoirs 25 and 26 in the positive and negative pulse pressure systems provide the bursts of air necessary for very abrupt pumping action when desired. Thedamping valves 29 and 30 in the systolic and diastolic lines provide damping for the purpose of shaping the contour of the pumping action to that of the natural heart pumping function.

Thesolenoid valves 27 and 28 are controlled by anelectronic programmer 32 which is adjustable to provide any systolic to diastolic ratio as well as any pumping rate desired by the operator. Obviously, the electronic programmer serves the function of simultaneously openingsolenoid valve 27 while closingsolenoid valve 28 and vice versa with the duration during which either valve is open'being adjustable to obtain the desired systolic to diastolic ratio. The cycle comprised of opening eachvalve 27 and 28 in alternating fashion determines the rate of the pumping action.

The sustained negative pressure system is comprised of asustained vacuum source 33 coupled to the sustained negative pressure line ortubular opening 16 through avacuum regulator 34, aliquid trap 35 andconduit 36. No reservoir is necessary in the sustained negative pressuresystem as there is hardly any air movement except for some air bypassing the ventricles in the cup. Additionally no pulsatile action is provided for the sustained negative pressure system. Theliquid trap 25 collects any fluids that may be drawn into the sustainednegative pressure conduit 36.

Typical pressures which may be used in the pumping of the ventricles are as follows:

Systolic pressure 125 millimeters of mercury Diastolic pressure 100 millimeters of mercury (Vacuum) Sustained negative pressure (Vacuum) The pumping rate is adjustable over a rather broad range as is the systolic to diastolic ratio. The pressure (and vacuum) levels are also adjustable over a wide range.

Thesystem 20 of FIG. 2 may generally provide two types of assistance, i.e., the nonsynchronized and the synchronized types. In the case of nonsynchronized assistance the actual pumping action of the heart muscle is stopped by a method known as fibrillation. To fibrillate the heart, a small alternating current (AC) voltage is applied across the heart at almost any two arbitrary points on the surface of the heart. The application of this small alternating current voltage depolarizes the natural electrochemical stimulation of the heart causing fibrillation of the heart during which the heart experiences only a slight twitching which has no decided orientation and hence performs no pumping action. When the ventricular cup is applied and the mechanical ventricular assistance is initiated, the heart after having been defibrillated, does not interfere or buck the pumping action of the mechanical system since it is not pumping.

In the case of synchronous assistance, the pumping action must be synchronized (with appropriate delays) to the natural electrocardiac signal of the heart. It therefore becomes necessary in order to perform synchronous assistance,.to monitor the electrocardiac signal and inject appropriate delays in order to synchronize the mechanical assistive pumping action provided by the assistor cup assembly with the natural rhythm of the heart which is controlled by the electrocardiac signal. In addition to synchronous assistance, suitable pacemaker means (not shown) may be coupled to the heart for pacing the heart. In situations where the heartbeat is irregular, (i.e. beating either too fast or too slow or adding or omitting an occasional beat) the pacemaker device is provided to add a beat, omit a beat or generally control the heartbeat in an effort to achieve a normal sinus rhythm. The above mentioned electrodes may be utilized in conjunction with the pacemaker for this purpose.

The pump system of FIG. 2 employing thecup assembly 10 effectively places the blood in indirect contact with the pumpsince the heart is mechanically assisted and therefore still performs its pumping function. The results of experimentation to date show that survivals have readily been achieved after 36 hours of continuous assistance of a fibrillating heart, which is far beyond the capability of any other available circulatory system. Whereas the ventricles are positioned within the cup during the assistance operation, any other portion of the body, including the aorta which lies immediately above the cup, is available for surgical or other treatment. The use of the mechanical assistor system is believed to significantly reduce the strain on an ailing heart allowing the heart to become rejuvenated during the mechanical assistance operation to regain the ability to independently assume the circulatory function.

In the field of organ preservation, the system of the present invention has enormous possibilities. Any donor of organs (who may be referred to as a cadaver) may be held in readiness for a transplant for more than 24 hours with no extensive operation but for the application of the ventricular assistor cup to the heart ventricles. Thus all organs of the body except perhaps for the ventricles, can be held in constant readiness for transplant purposes. Transplants have already been performed employing the assistor pump system described therein in both humans and animals involving the kidneys and liver.

The mechanical ventricular assistance system described herein lends itself also to emergency use and may be provided l80 millimeters of mercury in vehicles such as ambulances allowing for the cup to be attached within a matter of 2 minutes or less by authorized personnel so as to provide adequate time for organ preservation or for survival of the patient upon the return trip to the hospital or to other medical assistance.

The simplest form of mechanical ventricular assistance may be performed upon a fibrillating heart. The heart may be safely fibrillated through electrical means by the application of a small alternating current signal. The application of the alter nating current signal causes the heart to move in a less abrupt and completely uncoordinated manner. Initiation of the mechanical ventricular assistance restores pumping action without bucking the natural pumping action of the heart (which has been terminated as a resultof fibrillation). In the example of the heart of a dog, it is known that once the heart is fibrillated it will not defibrillate or come out of fibrillation spontaneously by itself.

In the case of the human heart, spontaneous defibrillation is possible and it is even more likely in the, case of a monkey. Therefore, to provide unsynchronized ventricular assistance it is necessary in many cases to provide fibrillation current while the cup is on the heart. This necessitates the provision of electrodes within the cup. One of the electrodes may be applied directly to the body surface of the subject while the other may be located at a removed point of the heart within the cup assembly.

In order to provide for synchronized mechanical assistance with the ventricular cup, this necessitates the presence of a good electrocardiogram or electrocardiac signal. The electrocardiogram normally originates from the atria of the heart. When the ventricular cup is placed on the heart, hardly any electrocardiac signal can be obtained by conventional methods, namely by the application of electrodes placed in contact with external parts of the body. The electrically insulating properties of the cup also prohibit electrocardiac signals from being obtained.

In addition to the above, the mechanical pumping action of the heart tends to produce an appreciable amount of noise which is superimposed on the already weak electrocardiogram. For this reason, it has been found that the placing of an electrode within the cup in an isolated position away from the remaining portion of the heart is an effective method for obtaining good results. Thus, by placing one electrode within the cup, while the patient serves as the other electrode, an extremely good electrocardiogram has been obtained.

When it is desired to terminate mechanical ventricular assistance which has been performed upon a fibrillating heart, the heart must be defibrillated or polarized with a high voltage pulse generally applied across the opposite sides of the central axis of the heart, although any two arbitrary points are satisfactory. This voltage may reach over 200 volts and is applied in the form of a short pulse having a pulse duration of the order of one-half second in order to defibrillate the heart and restore natural pumping action.

In the case of treatment of a patient with a weak heart, there is no assurance that defibrillation will readily occur and the repeated removal of the cup to attempt defibrillation without success will result in extended periods without assistive circulation. For this reason, it is most desirable to provide electrodes in the cup to permit defibrillation while the cup remains on the heart and is continuously providing mechanical assistance of the circulatory function. In order to perform defibrillation it is desirable to provide two large electrodes on opposing sides of the ventricles.

FIG. 3 shows a sectionalized view of the ventricle assistor cup having the desired electrodes. Like elements as between H68. 1 and 3 have been designated with like numerals.

As was previously described the rigid (glass) shell 11 surrounds the flexible liner ordiaphragm 12. An electrode for perfonning either fibrillation or synchronization may be provided at a location immediately above the apex connection to the sustainednegative line 16 or near thelocale 14 at which theliner 12 is attached to the interior surface of the glass shell 1 l.

Considering first the electrode positioned adjacent the apex of the cup, the cup is provided with a substantially annular shaped groove 41 provided along the exterior surface of the cup. The interior surface of the cup is provided with acontinuous shoulder 42 whereby the lower edge of the flexible liner l2 abuts againstshoulder 42 when affixed to the interior surface of the cup by a suitable adhesive material as shown at 15. The annular shaped groove 41 is coated with a conductive material ormetal film 43. Similarly the interior surface ofcup 11adjacent shoulder 42 is coated with a platinum or goldnonreactive film 44 which can be readily fired on the cup. This conductive film is exposed to the ventricles of the heart and is free to make good electrical contact therewith. The sustained negative pressure applied through opening 16 causes the ventricles of the heart to come in firm contact withconductive surface 44 provided along the interior surface of the cup.

A conductive path is provided between the twoconductive films 43 and 44. One method of providing the electrical path is to form a small opening 45 through the cup and fill or line this opening with a suitable conductive material which electrically connects thefilms 43 and 44. An outer electrical connection to a wire or other terminal (not shown), may be provided through the use of thestainless steel clip 46 having a substantially circular configuration. Theclip 46 is preferably resilient and after being snapped into the annular groove 41 makes firm electrical contact withconductive film 43. The circular portion of the clip 45 resting in groove 41 (as well as groove 41) may be covered with a suitable insulating material such as for example an epoxy. Thebent portion 46a ofclip 46 may extend beyond the epoxy coating and is exposed to be electrically coupled to a wire or other terminal. Theconductive film 44 making electrical contact with the heart serves as one electrode with the other electrode (not shown) being the body of the patient. The other electrode may, for example, be placed in electrical contact with the back of a patient and near the shoulder for example. Obviously, this electrode may be positioned at any other desired location on the body to provide a good electrocardiogram. These electrodes maybe coupled to the electrocardiogram instrument in any suitable fashion allowing the electrocardiac signals to control the pumping action of the system shown in FIG. 2. Alternatively, the clip may be replaced by a simple lead electrically connected toconductive coating 43 by an epoxy or alternatively by solder and then a coating of epoxy.

The above mentioned electrodes may also be utilized to fibrillate the heart through the application of a small alternating current through the electrodes.

For defibrillation of the heart while mechanical ventricular assistance is being provided or while the heart is still within thecup assembly 10, two large electrodes may be provided within the cup assembly located on opposing sides of the ventricles. Theseelectrodes 47 and 48 may be applied directly to the exposed interior surface of the flexible liner l2. Suitable small openings may be provided through the liner [2 and thecup 11 to provide for passage offlexible leads 49 and 50. The openings provided in the liner [2 andcup 11 may be suitably sealed as shown at 51 and 52 along cup ll, for example, to insure the fact that no pressure pulses applied throughline 18 will escape by passing either throughcup 11 or throughliner 12. It can be seen thatliner 12 is continuously sealed tocup 11 atlocations 14 and so that any positive pressure pulses applied toline 18 cause deformation offlexible liner 12 in the manner shown in FIG. 1 and so that any negative pressure pulses (i.e., from thevacuum source 22 of FIG. 2) cause return of the liner to the solid line positions 12 shown in FIGS. 1 and 3.

desired although this is not completely necessary to preserve the sustained negative pressure applied to the heart ventricles.

In the embodiment shown in FIG. 3, theelectrodes 53 and 54 may be employed for the purpose of obtaining electrocardiac signals; andelectrodes 47 and 48 or electrode 44 (together with a remote electrode) may be employed for the purpose of performing fibrillation or defibrillation of the heart. As an alternative to the electrode arrangements of FIG. 3, it has been found that theelectrode 44 in combination with another electrode appropriately affixed to the body may be employed for performing all functions, i.e., the monitoring of electrocardiac signals, fibrillation, defibrillation and electrical pacing of the heart with the same degree of success obtained through the use of the electrode pairs 53-54 and 47-48 respectively, so as to greatly simplify the ventricular assistor cup assembly. Thus, the oneelectrode 44 may be coupled through suitable mechanical or electronic switching means to selectively couple the electrode to either an electrical source for fibrillation (i.e., a small alternating current source); an electrical source for defibrillation (i.e., a suitable DC pulse generating source); an electrocardiograph instrument and a pacemaker.

It can be seen from the foregoing that the present invention provides a ventricular assistor cup assembly for applying a direct pumping action to the ventricles of the heart while simultaneously and/or selectivelyenabling monitoring of electrocardiac signals and fibrillation and/or defibrillation and/or pacing of the heart during the period in which the cup is positioned upon the heart and without any need for removing the cup during the performance of these functions.

Although there has been described a preferred embodiment of this novel invention, many variations and modifications will now be apparent to those skilled in the art. Therefore, this invention is to be limited, not by the specific disclosure herein,

but only by the appending claims.

I claim:

1. A cup assembly for use in applying pumping action to the heart comprising: I

a substantially rigid cup having a configuration substantially conforming to the configuration of at least a portion of the heart;

said cup having a first opening for receiving a portion of the heart and positioning said portion within the interior of the cup, and having second and third openings communicating with the interior of said cup;

at least one of said second and third openings being located at the apex of said cup which is furthest removed from said first opening and the remaining one of said second and third openings being located along the surface of said cup at a position intermediate the first and apex openings;

a flexible liner being positioned within said cup and having a configuration substantially conforming to the interior surface of said cup when the liner is in a relaxed position;

a first continuous marginal edge of said liner being positioned against the interior surface of said cup adjacent to and surrounding said first opening;

a second continuous marginal portion of said liner being positioned against the interior surface of said cup and adjacent to and surrounding the opening in said cup provided at the apex of said cup;

means for securing said continuous marginal edges of said liner to the interior surface of said cup in the region of said first opening and the opening at the apex of said cup respectively;

said liner being adapted to act as a barrier to the said remaining opening in said cup such that any pressure applied to said remaining opening will be confined to and contained within the hollow region defined by the interior surface of said cup, the opposing surface of said liner and said sealing means;

an electrode being affixed to the interior surface of said rigid cup adjacent the opening in the apex of said cup and spaced from said liner for making electrical contact with the portion of the heart positioned within said cup;

an electrical terminal positioned along the exterior surface of said cup and means for electrically connecting said electrode to said terminal; and

a second electrode affixed to the exterior surface of the body of the patient receiving the cup assembly which is adapted to cooperate with the electrode mounted within said cup to control the operation at monitoring of the heart.

2. The cup assembly of claim 1 wherein said electrode is comprised of a substantially annular shaped metallic coating being deposited upon the interior surface of said cup adjacent to and surrounding the opening in the apex of said cup.

3. The cup assembly of claim 2 wherein said terminal is comprised of a substantially annular shaped conductive coating deposited upon the exterior surface of said cup adjacent to and surrounding the opening provided in the apex of said cup.

4. The cup assembly of claim 3 wherein said cup is provided with a small opening communicating with and extending between said electrode and said terminal and containing an electrically conductive material for establishing a conductive path between said electrode and said terminal.

5. The cup assembly of claim 4 wherein said cup exterior surface is provided with a substantially annular shaped groove for receiving said terminal;

conductive clip means conforming to the configuration of said groove and being positioned within said groove to make good electrical contact with said terminal; and

saidclip having a projection for facilitating the connection of an electrical lead thereto.

6. The cupassembly of claim 5 further comprising an insulatingmaterial deposited upon said metallic clip to electrically insulate said clip and firmly afiix said clip to said cup while at the same time exposing the projection on said clip to facilitate electrical connection of a lead thereto.

7. The cup assembly of claim 1 further comprising a pair of electrical leads being affixed to the exposed interior surface of said liner on opposite sides of the central axis of said cup and intermediate the first and apex openings in said cup;

a pair of flexible leads each being affixed to an associated one of said pair of electrodes and passing through suitable openings in said liner and said cup to facilitate connection of external circuitry thereto.

8. The assembly of claim 7 further comprising sealing means for sealing the openings in said liner and said cup provided for the passage of said flexible leads to prevent the escape of any gaseous substance introduced into the hollow region defined by said liner and said cup.

9. The cup assembly of claim 1. further comprising a pair of electrodes affixed to the interior surface of said cup assembly adjacent said first opening and on opposite sides of the central axis of said cup and in the region where said liner experiences no flexing as a result of inflation and/or deflation; a pair of flexible leads each being coupled to an associated one of said pair of electrodes;

suitable openings being provided in said cup assembly to provide for the passage of said flexible leads in order to facilitate the connection of electrical circuits thereto.

10. The cup assembly of claim 1 wherein said electrode affixed to the interior surface of said cup is comprised of a nonreactive conductive film.

11. The cup assembly ofclaim 10 wherein said nonreactive film is platinum.

12. The cup assembly ofclaim 10 wherein said nonreactive film is gold. 13. The assembly of claim 4 further comprising:

an electrical lead connected to said terminal for coupling said electrode to external circuitry; and epoxy means deposited upon said terminal and said lead for maintaining the electrical connection thercbetween. 14. A cup assembly for use in applying pumping action to the heart comprising:

a substantially rigid cup having a configuration substantially conforming to the configuration of at least a portion of the heart; I said cup having a first opening for receiving a portion of the heart and positioning said portion within the interior of the cup, and having second and third openings communicating with the interior of said cup;

at least one of said second and third openings being located at the apex of said cup which is furthest removed from said first opening and the remaining one of said second and third openings being located along the surface of said cup at a position intermediate the first and apex openings;

a flexible liner being positioned within said cup and having a configuration substantially conforming to the interior surface of said cup when the liner is in 'a relaxed position;

a first continuous marginal edge of said liner being positioned against the interior surface of said cup adjacent to and surrounding said first opening;

a second continuous marginal portion of said liner being positioned against the interior surface of said cup and adjacent to and surrounding the opening in said cup provided at the apex of said cup;

means for securing said continuous marginal edges of said liner to the interior surface of said cup in the region of said first opening and the opening at the apex of said cup respectively; v

said liner being adapted to act as a barrier to the said remaining opening in said cup such that any pressure applied to said remaining opening will be confined to and contained within the hollow region defined by the interior surface of said cup, the opposing surface of said liner and said sealing means; v

an electrode being affixed to the interior surface of said rigid cup adjacent the opening in the apex of said cup and spaced from said liner for making electrical contact with the portion of the heart positioned within said cup;

an electrical terminal positioned along the exterior surface of said cup and means for electrically connecting said electrode to said terminal;

a second electrode affixed to the interior portion of said cup overlying said rigid cup portion and spaced from said first electrode; and

means for connecting said second electrode to an external device for monitoring the heart. 7

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