JP3489643B2 - Telemetry device for information on operating characteristics of implanted prosthetic heart valves - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates generally to an improved heart valve prosthesis, particularly implantable to replace a defective human heart valve or prosthetic heart valve, and the operating state of said valve. And other biological data for monitoring and telemetry and transmission to an external receiver, as well as a prosthetic device for delivering pacing stimulation pulses. The improved prosthetic device of the present invention employs at least one, preferably two or three occluders, each occluder being a flat or curved plate or leaflet.
, And both function hemodynamically by the periodic opening and closing movements generated through the normal pumping action of the heart. The improved prosthetic device may alternatively employ multiple occluders, such as two or three flat or curved plates, or alternatively a ball check non-occluder with holder. Sensors are incorporated to detect events such as leaflet motion, and transmitters / receivers (transceivers) are incorporated to send and receive data and instructions from external devices.

[0002]

BACKGROUND OF THE INVENTION As is well known in the art, heart valve prostheses essentially function as check valves. Blood flow resulting from the heart's natural pumping action causes the leaflets to open periodically, while circulatory system pressure closes the leaflets during diastole when in the aortic position or during systole when in the atrial-ventricular position. Let

Various heart valve prostheses have been proposed and used in the past. Some of these prosthesis devices employ a ball configuration with a holder, which also functions in response to the normal pumping action of the heart and controls blood flow. It has been discovered that the holder-equipped ball configuration is not desirable from a psychological point of view due to the audible clicking sound that is emitted when the ball is seated in and out of the opening in the valve body. Other heart valve prostheses have employed occluders that take the form of either a disc or a pair of semi-circular and semi-elliptical plates. The latter is a bi-leaflet.
t) Usually called a valve. Although various structural materials have been employed in the past, the most recently utilized heart valve prostheses are made primarily of pyrolytic carbon.

Bi-leaflet valves usually employ pivoting means designed to appropriately guide or control the movement of the leaflet as it moves between its open and closed positions. In addition, means are provided for controlling or limiting the degree of movement of the leaflets during opening or closing, thereby carefully guiding, controlling, limiting and maintaining movement of the individual leaflets. I will provide a.

[0005]

It is further known that the blood components, including cells, normally found in human blood are extremely fragile and delicate. These cells can be damaged and / or destroyed if subjected to abnormal mechanical forces. Therefore, care must be taken to control the nature of the forces generated during relative movement between the leaflets and their surrounding annular body members. For example, reducing the occurrence of abrasive contact between stationary and moving surfaces is such that when such contact is likely to cause mechanical damage to the various types of cells present in the blood,
is important. In the design and construction of the heart valve prosthesis of the present invention, care is taken to reduce the occurrence of zones or areas where blood passing through the device is exposed to substantial mechanical forces. Thus, the operation of the valve of the present invention is particularly noiseless, and conventional acoustic techniques cannot be used to evaluate the operating performance of such "silent" valves. Therefore, it is desirable that some alternative method of monitoring valve performance and other physiological parameters be incorporated into or with the valve.

[0006]

The heart valve prosthesis of the present invention is US patent application Ser. No. 08 / 122,802, filed Sep. 16, 1993, and is currently referred to as "HEART VALVE PROSTHESI".
U.S. Pat. No. 5,354,33 issued under the title "S)".
No. 0 improvement, the technique of which is incorporated herein. The features of the present invention are readily applicable to other types of valves, including tissue valves as well as other mechanical valves. United States Patent Application No. 08 / 122,802 (now US Pat. No. 5,354,330) discloses a heart having a generally annular body member with an inner surface defining a central passageway or lumen for passage of blood flow. A valve prosthesis is described.
The annular body member is preferably made of pyrolytic carbon,
And a pair of pivotable leaflets or occluders,
Means are provided for supporting within the annular body member such that they alternately open and close under the influence of blood pumped by the heart. Thereby, the heart valve prosthesis only allows one-way flow of blood through the lumen or passageway of the prosthesis. The annular body member is suspended in a stiffening ring, and a lock wire having a predetermined diameter is included in an annular groove formed in an outer surface of the annular body member and an inner surface of the stiffening ring, and Prevents longitudinal movement relative to the stiffening ring.

A cloth sewn cuff surrounds the outer surface of the stiffening ring. Located between the portion of the fabric sewn cuff and the stiffening ring, it is occupied by an electronic sensor as well as an implantable radio frequency transceiver and a suitable electronic component to provide a suitable active or passive power source to power it. There is a moisture-proof annular container or housing which also houses the printed circuit board.

The sensor may include any one of a number of types capable of detecting the motion of the occluder and providing an electrical signal to the implantable transceiver electronics that is indicative of the motion. Blood flow sensors may also be used. Thus, the implantable transceiver functions to transmit analog or digital information to a suitable monitor located external to the patient's body in which the valve of the present invention is implanted. The sensor functions to detect blood flow, stroke volume as well as some other information indicative of cardiac function during detection of the leaflet movement. The implantable transceiver may also include an external transceiver to perform certain physiological functions, such as provide cardiac stimulation pulses in the event of post-operative heart block, or otherwise control other arrhythmias. Can receive instructions from.

The foregoing features, objects, and advantages of the present invention are
It will be apparent from the following detailed description of the preferred embodiment and the accompanying drawings. In these attached drawings, those having the same function are designated by the same reference numeral.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT For reference, FIG. 1 shows a human heart 10 cut vertically, which includes a right atrium 12 and a left ventricle 1.
4, artificial heart valve prosthesis 16 to replace the regular mitral valve,
And a heart valve prosthesis 1 for replacing an aortic valve of a patient
8 is shown. The present invention may also be incorporated into a prosthesis that replaces the tricuspid valve.

As will be described in more detail below, one or both of the heart valve prostheses 16 and 18 are leaflets 20 and 22 as they open and close under the influence of blood flowing through the annular body member of the heart valve prosthesis 16. Appropriate sensors positioned and configured to detect normal movement of the can be incorporated into the prosthesis. The implantable sensor module 24 is preferably included within the valvular structure, as will be further described, but in accordance with another aspect of the invention, transceiver electronics are provided within a separate moisture-proof housing to provide a cardiac prosthesis. 16 to allow transceiver electronics to receive, amplify and transcutaneously transmit information through chest wall 26 to an external transceiver / monitor 28.

Referring now to FIG. 2, the heart valve prosthesis 16 preferably includes an annular body member 30 made of, but not limited to, pyrolytic carbon within which an occluder or leaflet is included. 20 and 22 are pivotally suspended. In FIG. 2, the leaflet itself is not shown. The outer peripheral surface of the annular body member 30 includes a groove 32 for receiving a lock wire 34, as fully described in the above-referenced US patent applications. A metal or plastic stiff surrounding the annular body member 30.
and a ring groove 38 for receiving a portion of the lock wire 34 is formed therein. Stiffening ring 36 may be constructed of a non-conductive material. The tolerance is determined so that the lock wire 34 prevents relative longitudinal sliding between the annular body member 30 and the stiffening ring 36 around it.

An upper groove and a lower groove are formed on the annular inner surface of the stiffening ring 36, and these grooves are formed in the first lock ring 4.
2 and a second locking ring 44, and is designed to tie the fabric sewn cuff 40. Since the cloth sewing cuff 40 is wrapped around the stiffening ring 36 and the locking rings 42, 44, the sewing cuff is constrained by the heart valve prosthesis 16.

US Patent Application No. 08 / 113,802
In the heart valve embodiment disclosed in U.S. Pat. No. 5,968,961, a plastic filler ring 58 is fitted between the stiffening ring 36 and the sewn cuff to form an annular flange. In the embodiment shown in Figure 2 herein, the filler ring is replaced by a moisture-proof ring-shaped housing 46, which preferably houses the electronic circuit 24 or sensor module of Figure 1. It is a welded titanium can designed for. The cross-sectional view of FIG. 2 shows a printed circuit board 48 within the housing 46, which is composed of integrated and discrete electronics including transceiver circuitry. The printed circuit coil antenna 50 is coupled to electronic circuitry on the printed circuit board 48 for transmitting and receiving electrical signals.

There is a suitable sensor element 52 housed within housing 46. The sensor element 52, which may be capacitive or inductive in nature, is suitably arranged to detect movement of the leaflets 20 and 22 (FIG. 1). An inductive transducer or sensor may include a coil positioned in the stiffening ring to be cut by magnetic flux from a dipole mounted on or in the leaflet. Other types of sensors for detecting motion and / or fluid flow through the annular body member 30 may be used, as will be apparent to those skilled in the art. For example,
An ultrasonic Doppler flow sensor may be used to detect the behavior of blood flow through the annular body member as the leaflet opens and closes. Further, a quartz crystal sensor may be adopted to detect vibration.

A suitable active power source, such as lithium iodide used in cardiac pacemakers, may be included in housing 46. Alternatively, a passive power supply may be used that includes an antenna 50 coupled to a storage capacitor through a suitable diode rectifier circuit, where the electronics within the housing 46 pass from the external transceiver / monitor 28 to the implanted heart valve electronics. It can be powered by a continuous wave high frequency signal transmitted transparently.

Atrioventricular nodules (AV n that control the ventricular rate)
OD) is located in close proximity to both the mitral and aortic valves, and it is not uncommon for the patient to temporarily or permanently fall into a heart block during the post-operative period,
It is desirable to provide a means for pacing or preparing the heart. In the past, it was practical to percutaneously place temporary pacing leads for connection to external pacemakers. Pacing leads for the heart are relatively expensive and require passages through the skin that can cause infections and ultimately require removal of the lead.

Since the lock wire 32 is a conductor and is in contact with blood, it connects this wire to the electronic pulse generator in the housing 46 and the transceiver / monitor 2
8 antennas 56 and said transceiver transceiver antenna 5
Ventricular pacing can be achieved by controlling the electronic pulse generator through a radio frequency link to and from zero.

During monitoring of the operation of the implantable heart valve prosthesis, an external transceiver /
Telemetry information to monitor 28 includes leaflet movements, pannus overgrowth on the ring.
allow diagnosis of events such as growth), arrhythmias, stroke volume.

If it is desired to diagnose a remote patient, a transceiver / monitor 28 located close to the patient
Are coupled via modems 58 and 60 to a remotely located personal computer 62 located, for example, in the office of a cardiologist, cardiologist, or emergency medical specialist.

FIG. 3 is a system block diagram showing the implanted electronics within the dashed box 64. As previously mentioned, the components of the implant electronics are included as an integral part of the heart valve prosthesis, as shown in FIG. 2, or alternatively, the power supply 66 and the implant transceiver 68 are external to the heart. However, it is packaged separately in a moisture-proof housing within the patient's chest. Only the sensor 70 and the electrodes 72 will be placed on or in the cardiac prosthesis itself. As mentioned above, the message is transcutaneously transmitted through chest wall 26 to external transceiver 28 and monitor 74, which may be a laptop computer or similar device, provided by sensor 70 to implantable transceiver 68, and Is programmed to analyze the information transmitted to the transceiver 28.

If an arrhythmia is detected, the system can be programmed to automatically initiate cardiac pacing. The monitor 74 delivers command pulses to the transceiver 28 at a predetermined pacing rate, which in turn will send commands to the implant transceiver 68, which applies the cardiac stimulation pulses from the pulse generator 69 to the electrodes 72. Can be controlled.
As described in connection with FIG. 2, the electrode 72 may include the lock wire 34 forming part of the heart valve prosthesis itself.

The present invention is provided in considerable detail to provide those skilled in the art with the information necessary to comply with patent law and to apply novel principles and use of specialized components as required. Explained here. It is noted, however, that the invention may be carried out by various instruments and devices, and that various modifications, both as to details of the instruments and operating procedures, can be accomplished without departing from the scope of the invention itself. There is no end.

For example, some or all of the components of the sensor module may be stiffened without the sensor module being placed in a moisture proof housing located between the sewn cuff 40 and the stiffening ring 36. It may be embedded in the ring 36. Therefore, the scope of the invention, when properly construed in light of the prior art, should be determined from the appended claims.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a heart illustrating a heart valve prosthesis according to the present invention used as a replacement for a mitral valve and an aortic valve.

FIG. 2 is an enlarged partial cross-sectional view showing a sensor module included within a sewn cuff of a typical heart valve prosthesis for percutaneously transmitting and receiving information and instructions to an external transceiver / monitor.

FIG. 3 is a block diagram of electronic circuitry associated with a heart valve prosthesis according to the present invention.

[Explanation of symbols]

16 Prosthetic Heart Valve Prosthesis 18 Prosthetic Heart Valve Prosthesis 20 Obturator, Leaflet 22 Occluder, Leaflet 24 Implantable Sensor Module 28 External Transceiver / Monitor or External Transceiver 30 Valve Body Member or Annular Body Member 32 Groove 34 Lock Wire 36 Stiffening Ring 40 Cloth Sewing Cuff 42 Lock Ring 44 Lock Ring 46 Container or Housing 48 Printed Circuit Board 52 Sensor Element 62 Personal Computer 66 Power Supply 68 Transceiver 69 Pulse Generator 70 Sensor 72 Electrode 74 Monitor

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Claims (14)

(57) [Claims] 1. A telemetry device for transmitting to a location external to a patient information regarding operating characteristics of an implanted prosthetic heart valve of the type including at least one occluder mounted within a valve body member. (A) detection means disposed on the transplanted artificial heart valve for detecting movement of the occluder with respect to the valve body member and generating a first electric signal indicating the movement; (b) inside the moisture-proof housing a power supply coupled to the transceiver means and the transceiver means disposed in said transceiver means wherein is operatively coupled to the detection means to receive said first electrical signal, and the from said housing prosthetic heart valve A transducing second electrical signal capable of transcutaneously electronically transmitting information regarding the first electrical signal to a location external to the patient being implanted. Telemetry device containing over bus means and said power source, and a monitoring means for receiving and analyzing the information provided outside the patient's body in order to receive and analyze the (c) the information. 2. The telemetry device according to claim 1, wherein
Capacitive change resulting from movement of the occluder by the detection means
Telemetry device to detect . 3. The telemetry device according to claim 1, wherein:
Induced changes resulting from movement of the occluder by the detection means
Telemetry device to detect . 4. The telemetry device according to claim 1, wherein:
The body portion in which the detection means results from movement of the occluder
A telemetry device that detects the vibration of materials . 5. The telemetry device according to claim 1, wherein
The detecting means is arranged in the blood passageway passing through the body member.
Not installed, telemetry device . 6. An artificial heart having a hollow body member defining a lumen and pivotably supporting at least one occluder, the body member having a sewn cuff covering an outer surface of the body member. In a combination including a valve and an electronic sensor module disposed between the sewn cuff and the outer surface,
The sensor module has a sensor element for detecting movement of the at least one occluder between an open position and a closed position relative to the lumen, the sensor module further comprising a signal transceiver coupled to the sensor element; A combination comprising power supply means for energizing the signal transceiver, means for encapsulating the sensor element, the signal transceiver and the power supply means in a moisture proof housing. 7. An artificial heart having a hollow body member defining a lumen and pivotably supporting at least one occluder, the body member having a sewn cuff covering an outer surface of the body member. In a combination including a valve and an electronic sensor module disposed between the sewn cuff and the outer surface,
The sensor module comprises a sensor element for detecting movement of the at least one occluder between an open position and a closed position relative to the lumen, and an implantable transceiver module, the transceiver module comprising: A wireless telemetry circuit operatively coupled to receive an input signal from the sensor element for a detected movement of the at least one occluder and provide an output signal to an antenna ;
Power supply for energizing the sensor element and the wireless telemetry circuit
A combination, including means . 8. The combination according to claim 7, wherein:
A combination wherein the sensor element comprises a capacitance element. 9. The combination according to claim 7, wherein:
A combination in which the sensor element includes a reactance element. 10. The combination according to claim 7, wherein
A combination in which the sensor element includes a vibration sensor. 11. The combination according to claim 10, wherein
A combination, wherein the vibration sensor is a quartz crystal. 12. The combination according to claim 7, wherein
The implantable transceiver module is attached to the artificial heart valve.
On the other hand, a combination that is external. 13. A combination according to claim 7, before
An external transceiver built into the artificial heart valve and
To receive a cardiac pacing signal via the antenna
The transceiver module for stimulating heart tissue when
A combination further comprising electrode means coupled to the tool. 14. The combination according to claim 13, wherein
A connection is provided between the transceiver module and the electrode means.
Combined with the heart transceiver received by the transceiver module.
Applying a cardiac stimulation pulse to the electrodes in response to the sourcing signal
A combination further comprising a pulse generator.