Removable heart pump, and method implemented in such a pump

0001The present invention relates to an artificial heart pump to regulate the blood flow, see e.g. <patcit id="pcit0001" dnum="WO2004101029A"><text>WO2004 / 101029</text></patcit>.

0002The heart is a hollow muscle with its rhythmic contraction ensures the progression of blood in the vessels. It has four cavities. The right atrium and the left atrium arranged in the upper portion of the core; the right ventricle and the left ventricle arranged in the lower part.

0003The right ventricle is intended to receive the blood from the right atrium and then eject it into the pulmonary artery. This constitutes a "small circuit" to send blood to the lungs for reoxygenation.

0004The left ventricle collects the oxygenated blood from the lungs via the left atrium and then eject into the aorta to deliver oxygen to all body tissues. This is the "great movement" called systemic circulation.

0005Heart failure (HF), progressive inability of the heart to supply blood flow necessary for the metabolic needs of an individual in everyday life, is the second cause of mortality in Western countries. The treatment of heart failure, which is to increase blood flow in a manner adapted to patient needs, is very effective with current techniques, and extremely expensive.

0006We know the document <patcit id="pcit0002" dnum="US20090024212A"><text>US2009 / 0024212</text></patcit> describing a pump for treating heart failure due to inactivity sigmoid heart valves. This pump has an elongated shape extending from inside the left ventricle to the interior of the aorta so as to replace the function of the valves.

0007Also known document <patcit id="pcit0003" dnum="US6217541B"><text>US6217541</text></patcit> describing a heart pump that is also inserted through the aorta into the interior of the ventricle. The end of the pump sucks the blood in the left ventricle and then transfer into the aorta via a flexible duct connected to the end of the pump and disposed through the valves.

0008The pumps described above requires extremely complex installation, and are not intended for permanent use.

0009Also known document <patcit id="pcit0004" dnum="US6234772B"><text>US6234772</text></patcit> describing an implantable rotary pump. This pump is the magnetic drive type and to force blood circulation, avoiding stagnant zone. This document is silent on any effective implementation of the pump.

0010The document <patcit id="pcit0005" dnum="WO2010010407A"><text>WO2010 / 010407</text></patcit> describes a rotary pump cardiac assist projecting the blood from the left ventricle through the aortic valve. This pump is secured through the aortic valve with mounting clips in the aorta and at the ventricular apex. The electric motor is located in the conduit passing through the aortic valve.

0011Finally we know the title <patcit id="pcit0006" dnum="US20050107657A"><text>US2005 / 0107657</text></patcit> describing a left ventricular assist pump (blood pump mixed flow) with a circuit called "radial" blood inlet and a circuit called "axial" blood ejection through a rotating propeller in the center of the device. The base is maintained in the left ventricular cavity by a rigid rod through the apex of the ventricle, while the top of the device passes through the aortic valve with modification or functional deletion of this valve. Surgically sternotomy with establishment of cardiopulmonary bypass is necessary because it takes incision at the root of the aorta. This document discloses also an optimal efficiency equation of the diameter of the pump and the number of revolutions / min propellant (up to 11 000 revolutions / min). The diameter of the pump is given in ~ 20-22 mm.

0012The present invention aims at a new pump slightly complex cardiac install compared to the implementation of current systems.

0013Another object of the invention is a simplicity in the maintenance of such a pump which is intended for long term use.

0014The invention also aims a minimally invasive pump into the ventricle of the heart and having a stability in its maintenance.

0015Is reached at least one of the aforementioned objectives with a heart pump, as claimed, comprising: <ul><li>an impeller inserted into the systemic ventricle of a heart, through the wall of the heart, this impeller being provided:<ul><li>a sealing membrane and fixing which is partly sutured on the external wall of the heart so as to connect the impeller with the heart wall,</li><li>a fixed casing, directly or indirectly, of the sealing and fixing membrane, said housing being arranged inside the systemic ventricle,</li><li>a motor disposed in the systemic ventricle and / or the thickness of the ventricle so as to suck and discharge the blood from the bottom, in the systemic ventricle, outside of the impeller and in the direction of sigmoid valves systemic ventricle, through the housing,</li></ul></li><li>a control unit comprising a power supply and an impeller control unit; and</li><li>a wire connection between the management unit and the impeller.</li></ul>

0016In particular, the motor may be a brushless motor is said "brushless".

0017Systemic ventricle means the ventricle dedicated to the bloodstream to supply the body of a patient with oxygen via the aorta. In principle, this role falls to the left ventricle, but in certain pathological situations, this role can be played by the right ventricle.

0018With the heart pump according to the invention, the impeller is secured to the heart wall, the patient can actively move without risk of injury. It acts directly on the blood flow by directly controlling the bloodstream. This pump is for all heart failure patients without pre-requisite criteria.

0019In the prior art as described in the documents <patcit id="pcit0007" dnum="US20050107657A"><text>US2005 / 0107657</text></patcit> and <patcit id="pcit0008" dnum="WO2010010407A"><text>WO2010 / 010407</text></patcit> in particular, the blood is propelled directly into the aorta because the pump through the aortic valve, this is not the case of the pump of the present invention. In the prior art, a pump replacement surgery requires a very heavy as it reaches the aortic valve.

0020The impeller can advantageously be a removable interchangeable block via the wall of the systemic ventricle. Moreover, the arrangement and shape of the impeller in the systemic ventricle mean that the impeller is fully accessible from the outside of the ventricle, and therefore interchangeable, allowing easy maintenance without heavy surgery type sternotomy. Replacement is easy in case of breakdown or wear.

0021Advantageously, the sealing and fixing membrane is fixed so as to ensure a complete seal and secure the impeller on the lower part of the heart near the apex of heart.

0022The impeller according to the invention is a biocompatible impeller types, eg rotary or projectional kind. Preferably, in the first case, the motor is rotating type and comprises a drive shaft type rotor with blades or worm, the drive shaft being disposed in the housing.

0023Preferably, the housing is an elongated cylinder, the side wall is perforated to allow the flow of blood drawn, and the axis of revolution is in the direction of sigmoid corresponding valves. Such an arrangement allows to eject the blood toward the sigmoid valves, but also can effectively suck the blood from the systemic atrium. Systemic headset means the headset associated with the systemic ventricle.

0024According to the invention the management unit can be disposed outside the patient, but it is preferably internally and preferably in the epigastric region in the upper part of the abdomen. Thus, unlike the prior art systems, the power supply according to the invention is preferably implanted as a whole without externalization. To do this diet can include at least one battery, preferably a rechargeable battery; recharging the battery can optionally be percutaneously transduction.

0025The pump according to the invention can thus be fully established and independent.

0026According to an advantageous feature of the invention, the pump may further comprise a probe, called an activity sensor to collect cardiac activity to synchronize the operation of the impeller with cardiac electrical activity; This activity sensor can be connected to a heart wall. It can be a wired connected to the management unit. This configuration allows to synchronize the operation of the impeller with the heartbeat.

0027In any integrated configuration, the sensor activity is connected to the management unit via said cable link. In this case, the wired connection is the only connection between the management unit and the impeller.

0028According to an advantageous embodiment of the invention, the heart pump includes a collection of probe cardiac activity and stimulation, called systemic probe connected to the wall of the systemic ventricle and capable of communicating with the way management unit wired or by wireless telemetry particular. This probe has a dual role of collecting information and the cardiac pacemaker to contract the muscle in response to an instruction from the management unit. A second similar probe, called non-systemic probe may be provided connected to the wall of the non-systemic ventricle and able to communicate with a wired control unit or not, by including wireless telemetry. In this case, you can order these two probes to achieve a bi-ventricular pacing. The ability to stimulate the heart to associate a direct action of the impeller on blood flow and an indirect action of cardiac contraction. The heartbeat detected by different probes also allows synchronizing the operation of the impeller with cardiac activity. In other words, the impeller is synchronized ventricular systolic activity when it is possible to collect information on cardiac activity, or can operate continuously.

0029One can also consider another probe collection of cardiac activity and stimulation, said probe headset connected to the wall of the systemic atrium and capable of communicating with the management unit to perfect the system of collection cardiac activity and stimulation. Communication can be wired or by wireless telemetry particular.

0030A probe is energetically autonomous when it communicates wirelessly with the management unit.

0031In addition in particular of the above, the pump according to the invention may advantageously comprise a collection of cardiac activity sensor, pacing and defibrillation, said defibrillation lead connected to the heart wall and connected to a wired management unit; the control unit further being configured as a defibrillator.

0032We can otherwise provide a management unit connected wirelessly to a defibrillator. This can be an external defibrillator (skin) or not, including automatic implantable independent but communicating with the electromagnetic waves by management unit.

0033According to an advantageous embodiment of the invention, further disposing a second impeller as described above on non-systemic ventricle and is also connected to the management unit.

0034As part of telemedicine, the management unit includes a wireless transceiver to transfer data to a monitoring Telecardiology. These data can be hemodynamic and rhythmic or data measured by all the pump sensors.

0035According to another aspect of the invention there is provided a method for controlling blood flow in a heart using a heart pump as described above. According to the invention, it regulates blood flow by controlling the speed and duration of operation of the pump from predetermined control laws or from a control instruction relating to the cardiac activity. With the slaving reference, blood flow is monitored in real time.

0036Advantageously develops the servo set by collecting cardiac activity by means of a sensor attached to the heart wall and a wired connected to the management unit. Can also regulate the blood flow by stimulating the heart by means of at least one stimulation probe connected to the heart wall and a wired connected to the management unit.

0037Other advantages and features of the invention will appear on examining the detailed description of a mode of implementation in no way limiting, and the appended drawings in which:<ul><li>The <figref idrefs="f0001">figure 1</figref> is a simplified schematic view of a heart pump according to the invention inserted in the left ventricle of a heart, and</li><li>The <figref idrefs="f0002">2</figref> is a schematic view of a heart pump according to the invention equipped with a plurality of epicardial leads or electrodes so as to effectively synchronize the cardiac pump relative to cardiac activity.</li></ul>

0038Although the invention is not limited thereto, will now be described a heart pump implanted in the left ventricle of a heart that is in principle the systemic ventricle. However, the invention can be applied equally to a right ventricle when the latter is systemic ventricle.

0039On the <figref idrefs="f0001">figures 1</figref> and <figref idrefs="f0002">2</figref>The elements common to the different variants or embodiments bear the same references.

0040On the <figref idrefs="f0001">figures 1</figref> and <figref idrefs="f0002">2</figref>, The heart is generally designated by the reference 1. There are the right ventricle 2 which is operable to eject blood into the pulmonary artery 3 through valves sigmoid 4. The left ventricle 5 has the function to realize the movement systemic ejecting blood filled with oxygen into the aorta 6 via valves sigmoid 7.

0041The right atrium 8 supplies the right ventricle 2 via blood atrio-pulmonary valves 9. The left atrium 10 supplies the left ventricle 5 in blood via the mitral valve 11.

0042The pump according to the invention comprises a control unit 12 connected by a wire 13 to an impeller 14 inserted into the left ventricle 5, at the apex, that is to say at the lower tip of the left ventricle .

0043The impeller has a preferably brushless motor types 15 placed inside the left ventricle (or systemic ventricle) so that it is easily accessible after a mini-thoracotomy (surgical incision) and or an operation epigastric path compared to a sternotomy where completely the thorax is opened. This engine can be a magnet drive motor with a rotor in the form of a drive shaft 16. The shaft may be of the "worm" ( "impeller") to eject blood from ventricle of the background to the aorta 6. This tree may also be a drive shaft with a propeller arranged at its free end. This propeller is shaped such that blood fluid dynamics to eject blood into the aorta 6.

0044A housing 18 of cylindrical shape is formed around the drive shaft. This casing 18 comprises at least one opening, preferably several openings bee nest for example, on its side wall so as to allow aspiration of blood from the left atrium and its discharge through the upper opening of the cylinder forming housing 18 by the action of the propeller, a worm or other ... 17. the rotation axis of the cylindrical housing 18 is directed to the aortic orifice. Such an orientation is preferably obtained during the implementation of the impeller by suturing. The skilled artisan will readily appreciate that other types of motors miniaturized biocompatible may be used for sucking and discharging the blood. Generally the materials used for the implementation of the pump according to the invention are biocompatible and can be implanted in the patient's body.

0045The impeller 14 is inserted into the apex of the heart and held there by means of a sealing diaphragm and attachment 19. Other types of membranes perfectly sealing engagement can be envisaged. This sealing and fixing membrane comprises a sealing membrane 19a associated, that is to say connected directly or indirectly to a fastening system 19b, such as a flange or any other system. 19b the fastening system is attached to the engine and / or the housing in the thickness of the heart wall. The sealing membrane 19a is preferably sutured on the external wall of the heart so as to ensure a total sealing between the left ventricle 5 (or systemic ventricle) and outside the core.

0046The waterproofing membrane and fixing may be differently shaped with or without fixation system arranged in the thickness of the heart wall.

0047The wired link 13 connects the impeller 14 to the management unit 12 which comprises a supply 23 such as a battery and a control unit 24 configured remotely. The wire link 13 has a control line 21 to the control unit 24 to send control instructions to the impeller 14, the control line 21 can be bidirectional. The cable 20 is an impeller of the motor power cable 15. The cable 22 allows electrically connecting the management unit 12 to an optional activity S1 probe inserted into the heart wall so as to collect cardiac activity of the heart. The S1 activity probe can be inserted through the sealing membrane and fixing 19 or beyond in order not to damage the seal. It may also be able to stimulate the left or right ventricle. In these cases, it is disposed in the wall corresponding to the left ventricle or the right ventricle.

0048With such a heart pump according to the invention, the connection between the management unit 12 and the impeller 14 is obtained by the single link 13.

0049In operation, the management unit is configured to modulate the rotational speed and the engine operating time according to predetermined laws or instructions. When has a probe to collect cardiac activity such as the activity sensor S1, the control unit 24 may be configured for controlling the motor heart rate in real time. This control makes it possible to synchronize the rotary impeller heart rate.

0050Preferably, the control unit is located in the epigastric region, within the patient's abdomen. It is thus possible that the control unit 24 is configured remotely by wireless communication.

0051On the <figref idrefs="f0002">2</figref>We see an example of a heart pump according to the invention in an embodiment incorporating many epicardial leads or electrodes.

0052The probes arranged on the core types are gathering information and pacemaker. They identify the beginning of the electrical activation and synchronization of the impeller on the opening of the valves. When both ventricles are each subjected to an impeller, each impeller is synchronized with the opening of the corresponding valves. Advantageously, the frequency of each impeller is adapted so as to deliver preferably a stroke volume between 20 and 35 ml for each cardiac cycle.

0053Since the actuation of an impeller in a ventricle open valve (during systole) increases the amount of blood pumped, the pump according to the invention allows to increase the stroke volume and thus the blood flow.

0054According to the example illustrated in <figref idrefs="f0002">2</figref>The pump according to the invention comprises a probe for collecting cardiac activity and stimulation, called systemic sensor S2 allowing in particular to stimulate the left ventricle by muscle contraction. This systemic probe S2, connected to the management unit 12, is disposed within the heart wall in the left ventricle. Similarly another probe of cardiac activity and stimulating collection, called non-systemic sensor S3 is arranged on the wall of the right ventricle and connected to the control unit 12. It allows to stimulate the right ventricle by muscle contraction. The combined action of both sensors S2 and S3 enables a bi-ventricular pacing from the control unit 24 so as to maintain a heart rate according to a predetermined law or in response to data instructions.

0055On the <figref idrefs="f0002">2</figref>It also stands on the wall of the left atrium probe collection of cardiac activity and stimulation, said probe S4 headset connected to the control unit 12. Preferably, the control unit 24 can be configured to synchronize stimulation probes S2 systemic and non-systemic S3 compared to information collected from this sensor S4.

0056Complementing including the above, each of the S2 and S4 can play the role of the S1 sensor activity.

0057In order to deal with the risk of ventricular fibrillation, there is provided at least one patch or epicardial defibrillation sensor S5 arranged on the outer wall of the heart, the control unit being configured to both detect a situation of fibrillation and deliver shocks electrical high energy.

0058To fully apprehend the cardiac activity, there is provided an activity sensor 25 of the patient, such as an accelerometer or a pressure sensor, arranged for example in the management unit 12 or integrated with one of the aforementioned probes. Such a sensor can be useful for a patient with chronotropic incompetence to detect and report to the controller any acceleration of the patient's physical activity.

0059It also provides a hemodynamic sensor for detecting the hemodynamic status of the patient so as to complement the information obtained on the heart rate and effectively control the impeller. Hemodynamic sensor may be an endocardial acceleration PEA sensor type ( 'Peak Endocardial Acceleration "in English) implanted for example together with the S2 electrode.

0060The heart pump of the invention thus helps regulate blood flow to prevent heart failure. In addition, it may be implanted in the heart by minithoracotomy. The rotatable impeller can be inserted at the apex (bottom tip) of the left ventricle and if necessary a second rotatable impeller can be inserted at the apex of the right ventricle. Both impellers may advantageously be connected to a control unit placed in the epigastric region. It is thus a closed system without externalization of electrical equipment and food.

0061Of course, the invention is not limited to the examples just described and numerous adjustments can be made to these examples without exceeding the scope of the invention.