JP5808525B2 - Implantable device for intermittent occlusion of blood vessels - Google Patents

Description

  The present invention relates to an implantable device for intermittently occluding blood vessels, particularly veins exiting an organ system.

  Arterial blood supplied to the myocardium can provide nutrition while passing through healthy heart tissue, but it is difficult to reach ischemic tissue. As a result, the supply of nutrients to ischemic tissue and the excretion of catabolic substances by metabolism from such ischemic tissue is inhibited. In this context, it has been proposed to supply blood to ischemic tissue by retrograde perfusion. Retrograde perfusion of blood in the coronary vein plays an important role, especially in the field of myocardial protection during open heart surgery. Typical such interventions include, for example, balloon expansion of coronary arteries constricted by arteriosclerosis. The method, also known as percutaneous transluminal coronary angioplasty (PTCA), is by introduction of a balloon catheter into the area of coronary artery stenosis under x-ray control and inflation of a balloon located on the end of the catheter. Includes compression of atherosclerotic atheroma. During balloon dilatation, oxygen-containing blood is not supplied to tissues downstream in the artery, and functional changes within the ischemic region of the myocardium can already be detected when dilation lasts longer than 30 seconds. . Problems that arise as a result of myocardial ischemia protection also occur in other interventions for coronary angiogenesis, such as atherectomy, coronary endoprosthesis, and laser application. Lack of supply to the myocardial region is also present in acute myocardial infarction.

  For short-term ischemic protection, retrograde infusion of arterial blood or other nutrient fluid into the veins of the relevant ischemic myocardial region has been performed previously. In doing so, blood is pumped through each vein into the nutrient capillaries in the ischemic region to supply oxygen and substrate to the myocardium in that area.

  A device for retrograde injection of coronary veins capable of controlling pressure and performing intermittent occlusion of the coronary sinus has been known from US Pat. No. 4,934,996. The device includes, for example, an inflatable balloon catheter, a pressure measurement unit for measuring fluid pressure in the coronary sinus, and a control unit for generating a trigger signal for the occlusion means to initiate or release the occlusion, etc. Means are provided for occluding the sinus. The control unit measures the pressure maxima in the coronary sinus during each heartbeat, estimates the plateau value of the maxima of successive heartbeats and calculates the occlusion in the coronary sinus to the plateau value of the pressure maxima. Devised to be released on the basis.

  The occlusion of the coronary sinus causes an increase in pressure, so that blood is retrograde perfused through the respective veins into the nutrient capillaries of the ischemic region, allowing nutrient supply to that region. When the occlusion is released, retroperfused blood flows out vigorously and metabolic waste is carried away at the same time. In the method according to U.S. Pat. No. 4,934,996, a systolic pressure curve is thus estimated based on the measurement of the maximum pressure in the coronary sinus during each heartbeat, and intermittent occlusion is a function of the systolic pressure curve. It is controlled according to the plateau value. The estimated evolution of the systolic pressure curve also allows for a determination regarding the function of the heart, for example the slope of the curve reflects the contractility of the heart. The slope of the curve naturally also affects the height of the plateau value, and the lower plateau value is reached with a flatter curve, which eventually ends up after a long time at the time of induction of obstruction compared to a healthy heart. To be reached. Also, if the coronary vessels are occluded for a longer period of time during an intervention such as PTCA or stent placement, temporarily or due to complications, the pressure curve will rise more slowly and take a longer time to plateau The curve changes to reach

  Methods for intermittent occlusion of blood vessels and in particular the coronary sinus have also been known from WO03 / 008018A2, WO2005 / 120602Al, and WO2005 / 120601Al. Such a method is also applicable to acute myocardial infarction, and it has been proven feasible to reduce the infarct area by periodically occluding the outflow from the vein.

  It has also been proposed to redirect blood from coronary veins in areas where blood is well supplied into vascular areas where supply is poor.

  The devices known so far are exclusively suitable for the temporary treatment of patients during surgical intervention. Such interventions are in principle costly and require a physician other than to place an occlusive device in the blood vessel to be occluded. The operation of the occlusion device also requires permanent medical management. During intermittent occlusion, critical parameters must be monitored, such as the pressure in the occluded blood vessel, and the physiology as to whether the desired improvement in the condition, in particular the enhancement of the heart function, has actually occurred by treatment. Measurement must be continuously analyzed. In addition, it must be determined on the basis of the measured values what time the treatment, i.e. the intermittent occlusion procedure, can be terminated.

  The disadvantages associated with the methods and devices for intermittently occluding blood vessels known from the prior art are most likely that the patient has already experienced severe symptoms, i.e. already irreversible damage has already occurred. It is incapable of performing treatment before the time. It is not possible in principle to apply preventive application of intermittent occlusion of blood vessels already when the specific physiological parameters deviate slightly from the patient-specific desired values.

  The present invention is intended to reduce the cost of treatment and eliminate the need for permanent medical management by a doctor during treatment. An apparatus for intermittently blocking blood vessels known from the prior art is provided. The goal is to improve.

  The present invention further aims to greatly automate the control of intermittent occlusion. Said control must be carried out so that an optimal treatment result is achieved.

To solve this object, the present invention provides an implantable device for intermittently occluding blood vessels, particularly veins emanating from organ systems such as the coronary sinus. According to the invention, this device comprises:
Occlusion means operable for intermittent occlusion and positionable within a blood vessel;
At least one sensor for continuously or periodically detecting at least one physiological measurement;
An implantable controller provided with at least one physiological measurement and cooperating with the occlusion means to control intermittent occlusion in response to said measurement;
It is separate from the occluding means and comprises an implantable anchoring means that can be operably connected to the blood vessel and to which the occluding means is secured to position the occluding means relative to the blood vessel.

  This implantable device comprises all the components necessary for autonomous operation. In addition to an occluding means operable to intermittently occlude and positionable in a blood vessel, an implantable device allows the occluding means to be controlled in response to a measurement detected by at least one sensor. As such, at least one sensor and a control device are provided. This control includes, for example, pressure dependent control as described in US Pat. No. 4,934,996, WO 03 / 008018A2, WO 2005/120602 Al, and WO 2005/120601 Al. This control includes in particular the determination of the optimal time when the blood vessel is closed by the occluding means and the optimal time when the blood vessel is released again. Intermittent occlusion includes a plurality of alternating occlusion and release periods. Furthermore, the device according to the present invention comprises anchoring means separate from the occluding means, which can be used to position the occluding means within and relative to the blood vessel. By using this anchoring means, the occluding means and possibly at least one sensor, in particular in the axial direction, in such a way that the occluding means can be placed and operated fully automatically in the blood vessel for an extended period of time. It becomes feasible to fix in a durable manner. Treatment of the patient thus requires only a single surgical intervention by the physician, i.e. the implantation of the device according to the invention in the blood vessel of the patient, said implantation being not only an occlusive means, but also at least one sensor, control means And mooring means. After implantation, the patient can leave the hospital with intermittent occlusion of blood vessels as required. In this regard, it is conceivable that the onset of intermittent closure may be triggered externally, for example by the patient himself or by a doctor, or may be triggered automatically based on measured values detected by at least one sensor.

  In prior art intermittent occlusion devices, intermittent occlusion has been performed using a balloon that is introduced into a blood vessel, expanded to occlude the blood vessel, and deflated to release the occlusion. The expansion and contraction of the balloon was done by a gas or liquid medium that was fed into the balloon and sucked out again. Such occlusion means must on the one hand be provided with a suitable container for the liquid or gaseous medium in the patient's body and on the other hand the risk of balloon rupture and thus medium spillage is too high. , Not necessarily suitable for permanent embedding. According to a preferred further development of the device according to the invention, the closing means are therefore not mechanically or pneumatically operated, preferably mechanically or electrically driven with an electrically actuable drive. It is configured as a closing means. Such a mechanical or electrical drive for the closure means can be easily embedded and only requires an electrical energy supply to be provided to electrically operate the drive. This electrical energy supply can be implanted at an appropriate location in the patient's body in the same manner as a pacemaker, and the electrical connection wires to the occlusion means and the drive for the occlusion means are passed through the body. This electrical energy supply can, for example, be integrated into the control device to form a single component part, thus reducing the costs associated with surgical intervention.

  Various configurations of the mechanically or electrically driven closure means can be envisaged. According to a preferred configuration, the closing means can comprise, for example, an electrically actuable valve. This closing means can preferably comprise an electrically actuable actuator, for example formed by an electromagnet. The actuator can cooperate with at least one component part, the at least one component part between a position for occluding the blood vessel and a position for releasing the blood vessel in response to the operation of the actuator or electromagnet. It is movable. The actuator can, for example, cooperate with a foldable membrane. According to another embodiment, the actuator can cooperate with a locking member that is expanded and closed like an umbrella.

  A configuration in which the actuator is formed of a shape memory material can also be envisaged. The shape of such material varies depending on, for example, the applied voltage or temperature. Electroactive polymers can also be used in this context.

  In another configuration, at least one valve, for example made of conductive plastic, can be fabricated, which can itself be pushed away from the counter member, for example a further valve, depending on the respective charge state. That is, the valve is movable between a closed position and an open position. Such mechanisms have been known for example in connection with heart valves.

  In a configuration in which the occlusion means comprises at least one part that is movable between a closed position in which the blood vessel is occluded and an open position in which the blood vessel is not occluded, a preferred further development is that the electrically actuated part is movable. An actuator is provided that applies a force acting in a closing direction in cooperation with the actuator. As a result, when the prevailing pressure of stagnant blood causes a possible failure of the actuator, the moving parts are automatically reset to allow the blood to flow through the blood vessel without further obstruction. To ensure, the movable part is moved in the closing direction against the resistance of blood flow in the blood vessel and is therefore carried to the closed position. Therefore, the operational safety of the device according to the invention is greatly increased.

  In order to achieve proper anchoring of the occluding means, the anchoring means is preferably designed as a vascular implant, in particular as a radially expandable stent. Such stents are generally known in vascular surgery and can in principle be introduced into each vessel in a compressed form with a reduced outer diameter, after reaching the desired position, Designed to be in an expanded shape with an expanded outer diameter. In the expanded state, the stent applies a controlled radial pressure against the inner wall of the vessel to ensure that it is secured in the taken position. The holding force can be increased by a special structure of the stent jacket, for example a helical structure, or by friction enhancing means on the outer jacket.

  At least a portion of the actuator can be received within the stent.

  According to an alternative arrangement, anchoring means formed by an artificial blood vessel are provided. In this case, the implantation of the device according to the invention comprises the replacement of a part of the blood vessel with an artificial blood vessel, the artificial blood vessel being adjacent to allow anchoring means connected to the artificial blood vessel to be anchored. Connected to the natural blood vessel area.

  In a preferred manner, this arrangement is further developed so that the anchoring means comprises or forms a receiving space for the closure means. In this case, the occluding means are arranged directly in the anchoring means, for example a stent or an artificial blood vessel, with the advantage that the implant can be implanted as a prefabricated unit.

  As already mentioned, the control of the occlusion means is performed in response to at least one physiological measurement. In this context, this arrangement is preferably further developed so that a timing element is provided for the detection of at least one physiological measurement at predetermined time intervals. The shorter the predetermined time interval, the more precise the control. The reason is that each newest measurement is measured based on such control.

  In a preferred manner, a storage device is provided for storing physiological measurements and / or closure procedures, which is connected to a transmitter for wireless transmission of the contents of the storage device. In this case, for example, an external evaluation device may be provided to read data stored in the storage device wirelessly and to allow the patient and / or attending physician to perform data analysis or evaluation. In this way, it becomes possible to check the functional mode of the implantable device and provide periodic diagnosis in a simple manner.

  Control of the occlusion device can be performed in various ways. In a preferred manner, the sensor is fluid pressure, fluid volume, flow rate, electrical resistance, electrical impedance, cardiac current to establish an electrocardiogram (ECG), and / or metabolism such as blood oxygen saturation or pH or lactate content. It shall be configured to detect parameters. By doing so, one or several of these parameters can be measured. Usually, each measurement must be supplied to a calculation or statistical evaluation in order to generate an appropriate control signal for the occlusion means. This sensor can either be in an obstructed blood vessel, in particular on or near the occlusion means, or in a separate but similarly implantable extravascular unit with power supply and / or control device. Can be arranged. If several sensors are provided, at least one sensor can be placed in the blood vessel and at least another sensor can be placed in the separate unit.

  The fundamental object of the present invention is further achieved by a method for treating cardiac or circulatory disorders, including intermittently occluding blood vessels, particularly veins exiting the organ system, where the blood vessels are alternately occluded and released. can do. The method includes determining the magnitude of at least one physiological value of a patient at each time interval or continuously, storing each measurement value, obtaining a measurement value sequence, calculating the measurement value sequence, and In particular, statistical evaluation is performed, and intermittent closure is started or ended according to the evaluation result.

In order to perform this method, a device for intermittently occluding blood vessels, in particular veins exiting the organ system, is provided according to a further aspect of the invention, which device comprises:
Occlusion means that can be activated for intermittent occlusion;
Control means connected to the closing means;
At least one sensor for continuously or periodically detecting at least one physiological measurement;
A measurement value storage device which is supplied by a sensor and is adapted to store a measurement value sequence, the measurement value sequence being supplied to a control device, which is responsible for the calculation evaluation of the measurement value sequence and in particular statistical It is configured to perform the evaluation, and cooperates with the blocking means to start or end the intermittent blocking depending on the evaluation result.

  The method and apparatus are capable of fully automated operation, while at the same time being able to start and end treatments with intermittent occlusion of blood vessels, respectively, based on the calculation evaluation of measurement series and in particular statistical evaluation Allows time to be determined. Such an automated operation is required especially when the occlusive means is permanently implanted in the blood vessel. The reason is that in these cases, treatment by a doctor is no longer possible in principle. Therefore, it is necessary for the control device to determine whether and how long to treat with intermittent occlusion based on the measured values. For this purpose, a calculation evaluation of the measurement value series and in particular a statistical evaluation is provided by the present invention, where the intermittent occlusion procedure is started or terminated depending on the evaluation result. As already mentioned, the intermittent occlusion procedure in this case comprises a series of alternating occlusion phases in which the vessels are occluded and release phases in which the vessels are released.

  In order to allow the determination of the start time and end time of treatment as precisely as possible, according to a preferred further development, the calculation evaluation shall be performed after each measurement determination. The calculation evaluation thus takes into account the newest measured values so as to continuously update the evaluation results.

  The calculation evaluation itself can be realized by various methods. According to a first preferred mode of the procedure, the calculation evaluation of the measurement value series comprises converting individual measurement values of the measurement value series into converted measurement values so that a converted measurement value series is obtained. Including. Conversion is necessary, for example, when the physiological values used for evaluation cannot be measured directly. A measurable quantity in the context of the present invention preferably means blood pressure in that area of the blood vessel, blood mass or volume flow in that area of the blood vessel, electrical resistance, conductivity, in particular in the heart and / or lungs. It includes electrical impedance, ECG, and / or metabolic parameters such as blood oxygen saturation and / or lactate content or pH within that section of the blood vessel.

  According to a further preferred mode of operation, the evaluation evaluation of the measurement value series is such that the difference between the last two measurement values of the measurement value series, or the last two of the converted measurement value series, so that a set of difference values is obtained. Including determining the difference between the two converted measurements. Evaluation in this context can be realized in that intermittent occlusion is initiated or terminated when a given difference occurs. Such jumping behavior of such measurements may indicate a critical condition of the blood vessel or heart and thus requires an immediate start of treatment. However, the scattered jump of the measurement value may be regarded as an abnormal value due to, for example, an error in detection of the measurement value. In order not to take into account any such outliers in the evaluation, the calculated evaluation can preferably include a statistical evaluation, which provides a trend recognition and short-term outliers. Is suppressed.

  A calculated evaluation of a series of measurement values involves the measurement of individual measurements in order to detect an unacceptable or critical condition of a blood vessel or heart when a given absolute limit value is exceeded or does not reach the limit value. Comparing with a value can be included.

  Alternatively, attention can be paid to the relative limit values, and the arrangement relating thereto is preferably further developed so that the calculation evaluation of the measurement value series includes the determination of the cumulative difference of the difference value series. The cumulative difference reflects the difference between the last measured value and the first measured value of the measured value series.

  According to a further preferred mode of operation, the measurement evaluation of the measurement value series is carried out with the change per time in the measurement values of the measurement value series or in the converted measurement values of the converted measurement value series so that a derivative series is obtained. Including determining. The change in the measured value per unit of time reflects the rate of change and thus corresponds to the first derivative of the measured value curve over time.

  The number of measurements, for example blood pressure, blood volume or mass flow rate, varies with the cardiac cycle, and in principle only the respective maximum or minimum value during one heart beat is noted for evaluation. Therefore, a further preferred development form is that the calculation evaluation of the measurement value series determines the maximum value and / or the minimum value of the value of the measurement value series, the converted measurement value series, the difference value series, and / or the derivative series. Contemplated as well as a set of extreme values is formed from a local maximum or local minimum, respectively.

  Furthermore, it frequently happens that measurements, or local maxima and / or minima that occur during each heartbeat, rise or fall with each heartbeat during the occlusion phase. In this connection, it may be advantageous to use only the maximum value that occurs during the occlusion period for evaluation. Accordingly, another preferred mode of operation contemplates that the maximum or minimum value of the above-mentioned values occurring during occlusion, respectively, is selected as the local maximum or local minimum value.

  The control device, in which the evaluation of the measured value or the measured value series is performed internally, can cooperate with the occlusion device in various ways, and the time to start or end intermittent occlusion also in various ways. Can be determined. According to a preferred further development, in the context of the present invention, the measurement evaluation of the measurement value series comprises a measurement value series, a converted measurement value series, a difference value series, a derivative series, and / or an extreme value series, and / or Alternatively, including a comparison of the cumulative difference value with a given limit value, intermittent occlusion is initiated when the limit value is reached. In a resting state in which no intermittent occlusion occurs, it is monitored during the calculation evaluation of the measured values whether a given limit value has been reached. For example, heart contractility can be monitored by measurement. Furthermore, it is possible to diagnose ischemia by features that change in ECG, for example, by what is called “ST evaluation”. If the contractility or “ST evaluation” reaches or falls below a threshold that can be a predetermined value determined by the patient, the occlusion device is activated to perform intermittent occlusion. The onset of intermittent occlusion can also be determined, for example, using blood oxygen saturation or using pH and in particular lactic acid content.

  Another way to determine the optimal start time for intermittent occlusion is to determine the electrical impedance of the thorax or the area of the thorax, such as the lungs. The electrical impedance is inversely proportional to the fluid volume of the area to be detected, so that, for example, left heart dysfunction resulting in blood stasis in the lungs can be detected by electrical impedance. In this connection, see WO2008 / 070818A2.

  During intermittent occlusion, the measurements should be evaluated in the same manner as described above, thereby determining the optimal time to end intermittent occlusion. In this connection, a preferred further development is that the evaluation evaluation of the measurement value series is a plateau value of the measurement value series, the transformed measurement value series, the difference value series, the derivative series and / or its series of extreme values. It is contemplated that intermittent occlusion is terminated at a plateau value or at a predetermined percentage of the plateau value. Achieving a plateau value indicates that the characteristic measurement has changed and has reached a stable final value. When such a “steady state” is reached, the physiological parameter that was originally lowered below the critical value or raised above the critical value reaches the stable normal value again, thus terminating the intermittent occlusion procedure. can do.

  In a preferred further development, a new measurement series starts again at the beginning and / or end of intermittent occlusion, so that the evaluation is only based on measurements detected respectively after the last start or end of intermittent occlusion. Is done.

  However, the determined measurements can be used not only to determine the onset and end of intermittent occlusion, but also to control the individual occlusion and release phases of intermittent occlusion. Can do. In this connection, preferably each measurement determined during the occlusion of the blood vessel is subjected to a separate calculation evaluation, and the individual occlusion phase of intermittent occlusion is terminated according to the evaluation result. The same applies to the release period, and preferably each measurement determined during the release of the blood vessel undergoes a separate calculation evaluation, and the individual release periods of intermittent occlusion are terminated depending on the evaluation results. The

  In the following, the invention is explained in more detail by way of exemplary embodiments schematically illustrated in the drawings.

1 shows an implantable device according to the invention in an implanted state. It is sectional drawing which shows the occluding device which can be implanted. It is a figure which shows the pressure curve provided by the pressure sensor. FIG. 3 is a diagram showing a first derivative of a pressure curve. It is a figure which shows the curve which approximates to the maximum value of a pressure curve and a 1st derivative. FIG. 5 shows a curve according to FIGS. 3 and 4 over multiple occlusion and release periods.

  FIG. 1 schematically shows a human heart 1. Within the coronary sinus 2, an occluding means 3 is arranged that can be actuated to intermittently occlude the coronary sinus 2. Control means for actuating the closing means is indicated at 4. The measured value of the sensor 5 is supplied to the control device 4 via wiring. The sensor 5 is designed as a blood pressure sensor that measures the pressure in the coronary sinus, for example. An electrode 6 is further connected to the control device 4 so that a current pulse can be generated. With respect to the heart 1 and lungs (not shown), a sensor 7 placed diametrically opposite the electrodes 6 can be used to detect the electrical impedance of the thorax, or the heart 1 and lungs, so that the heart 1 contracts. Judgment regarding sex becomes possible. In addition, although a sensor 22 can be provided that serves to measure the conductivity of blood in the coronary sinus, studies have shown that blood conductivity is a measure of heart contractility. The measured values from the sensors 5 and 7 are evaluated by the control device 4, and the closing means 3 is activated according to the evaluation result. In particular, the length of individual occlusion and release periods is determined during intermittent occlusion. Based on the measurements, the optimal time for starting and ending intermittent occlusion is further determined. The exact control algorithm is shown as an example in FIGS.

  The power supply of the control device 4 and possibly the closing means 3 is indicated by 8.

  FIG. 2 shows the coronary sinus in detail and it is clear that the anchoring means 9 designed as a stent has been inserted into the coronary sinus 2. The stent 9 cooperates with the inner wall of the coronary sinus 2 to fix the stent 9 in place. The direction of blood flow with the occlusion means 3 open is indicated by 10. The stent 9 carries a pressure sensor 5 that measures the pressure in the coronary sinus 2. The occlusion means comprises at least two valve-like component parts 11, which are in a closed position in which the coronary sinus 2 is occluded and an open position in which the coronary sinus is opened, i.e. not occluded. Can exercise between. The movement of the valve-like component part can be effected by pivoting. FIG. 2 shows the valve-like component part 11 in the intermediate position. To close, the valve-like component part 11 is pivoted to the closed position against the direction of the arrow 10 and is held in that position by the power load. As soon as the power load is stopped, i.e. the operation of the occlusion means is terminated, the valve-like component part 11 is automatically pushed open by the prevailing blood pressure, thereby automatically opening the coronary sinus. With such a configuration, the coronary sinus 2 is automatically opened when a malfunction that may occur due to, for example, power consumption occurs, so that the living body is not damaged by such malfunction. .

  When the occlusion means closes the coronary sinus 2 during the occlusion phase, blood stagnate in the coronary sinus 2 and perfuses retrogradely into the surrounding tissue. When opening the occlusion means during the subsequent release phase, the stagnant blood is washed away. The alternating occlusion and release periods are repeated until an improvement in the situation is confirmed based on the measurements.

  The stent 9 is connected to two electrical wires 12, one of which transmits the measurement value of the sensor 5 to the control device 4, and the other of the wires 12 electrically activates the closing means. To work.

  FIG. 3 shows measured values detected by the pressure sensor 5. The pressure curve shows the pressure transition over time in mmHg. It is clear that the maximum pressure that occurs at each heartbeat increases with each heartbeat during the occlusion period 13 until the maximum pressure indicated at 15 reaches the upper plateau value. During the release period 14, the pressure drops rapidly, causing the maximum pressure value to reach the lower plateau value. The maximum pressure value 15 forms a set of extreme values. The maximum pressure value 15 can be approximated by a curve 16 (occlusion period) and a curve 17 (release period). This approximation is preferably done according to the least error square method. The selection of the duration of the individual occlusion phase and release phase can be made based on the approximated curves 16,17.

  However, the selection of the duration of the individual occlusion and release periods can also be made based on the time derivative dp / dt of the pressure curve. The first derivative dp / dt of the pressure curve is shown in FIG. The curve again shows the maximum and minimum values of the first derivative that occur during each heartbeat. The local maximum point indicates the time at which the pressure rise occurs most rapidly. The local minimum point indicates the time at which the pressure drop occurs most rapidly. FIG. 4 shows a curve 18 approximating the local maximum of the first derivative and a curve 19 approximating the local minimum of the first derivative. It is clear that the maximum value of the first derivative that occurs in successive heartbeats in the first derivative rises until reaching a maximum value at point 20 during the occlusion period and then decreases again. The same is true for the first derivative minimum point 21 occurring at successive heartbeats. Points 20 and 21 can be determined by calculating with the derivatives of approximate curves 18 and 19 being zero.

  The positive value of the time derivative dp / dt of the pressure curve (i.e. curve 18) serves as an index of the heart's contractility and the occlusion period 13 is terminated when the contractility reaches a maximum. However, the contractility of the heart can not only be determined by the time derivative dp / dt of the pressure curve, but instead is determined based on the conductivity of blood in the coronary sinus detected by the sensor 22. You can also

  FIG. 5 shows a curve 16 that approximates the maximum value of the pressure curve and a curve 18 that approximates the maximum value of the first derivative dp / dt of the pressure curve. It is clear that the maximum value 20 of the curve 18 provides a reference point for the end of the occlusion period that is much better discernable and clearer than the plateau value of the curve 16.

  The negative value of the time derivative dp / dt can also be used to determine the optimal time to end each occlusion period. The negative value of the time derivative dp / dt serves as an indicator of the cardiac relaxation period. The time of maximum pressure drop rate (the time of each local minimum of the first derivative occurring during each heartbeat) is actually the beginning of the heart's isovolumetric relaxation phase. If the occlusion period takes too long, the isovolumetric relaxation period will be shortened. To prevent such shortening, the occlusion phase must be terminated on time. This continuously evaluates the first derivative of the pressure curve with respect to the local minimum and, in combination with the determination of the cardiac current (ECG), allows the calculation of the duration of the relaxation phase and the achievement of trend recognition. It will be realized by.

  FIG. 6 shows the pressure curve and the respective first derivative dp / dt for a plurality of consecutive closure and release periods. Approximate curves 18 and 19 are also shown, showing the maximum value 20 and the minimum value 21 that occur during each occlusion period, respectively. From the maximum value 20 and the minimum value 21, a set of extreme values can be formed, respectively, and this extreme value series is determined to determine the optimal time for ending intermittent occlusion based on the evaluation, It can be evaluated with respect to the development of maximum or minimum values. Successful treatment with intermittent occlusions can increase the value of point 20 from one occlusion period to the next, or at least recognizable over multiple occlusion periods. It can bring a tendency to rise. An increase in the value of point 20 allows a determination regarding an increase in myocardial contractility. When the value of point 20 reaches a given desired or plateau value, intermittent occlusion and thus treatment can be terminated.

  However, more frequently observed during treatment with intermittent occlusion is a decrease in the value of point 21. The value of point 21 represents the diastolic period of heart relaxation. The lower this value, the higher the left ventricular pressure drop rate, ie, the more rapid the pressure drop in the coronary sinus that is occluded during dilation. The determination of the end time of intermittent occlusion can also be made according to the value of point 21 in this way. Intermittent occlusion and thus treatment can be terminated, for example, when the value at point 21 reaches a given desired or plateau value.

  Even a combination of a change in the value of point 20 and an evaluation of the change in the value of point 21 can be useful.

  Continuous monitoring of defined physiological parameters, for example when electrical impedance measurements or thoracic and, in particular, heart and / or lung conductivity, indicates an increase in fluid volume within the region, If it is revealed that has decreased, further treatment may later be required again.

Claims (42)

An implantable device for intermittently occluding blood vessels,
An occluding means (3) operable to intermittently occlude and positionable in the blood vessel (2);
At least one sensor (5) for continuously or periodically detecting at least one physiological measurement;
An implantable controller (4) provided with the at least one physiological measurement and cooperating with the occlusion means (3) to control the intermittent occlusion in response to the measurement;
It is separate from the occluding means (3) and can be operatively connected to the blood vessel (2), the occluding means for positioning the occluding means (3) relative to the blood vessel (2). An implantable device comprising a radially expandable stent (9) as a fixed, implantable, vascular implant.   Implantable device according to claim 1, characterized in that the closing means (3) are configured as closing means (3) driven mechanically or electrically.   Implantable device according to claim 1 or 2, characterized in that the closing means (3) is connected to an electrical energy supply (8).   4. Implantable device according to claim 2 or 3, characterized in that the closing means (3) comprises an electrically actuable valve.   Implantable device according to claim 2, 3 or 4, characterized in that the closing means (3) comprises an electrically actuable actuator.   6. The implantable device according to claim 5, characterized in that the actuator is formed by an electromagnet.   The occluding means (3) comprises at least one component (11) movable between a closed position where the blood vessel (2) is occluded and an open position where the blood vessel (2) is not occluded, Implantable according to claim 5 or 6, characterized in that the actuator, when electrically actuated, cooperates with the at least one part (11) to apply a force acting in a closing direction. apparatus. Implantable device according to any one of the preceding claims, characterized in that the stent is formed by an artificial blood vessel.   Implantable device according to any one of the preceding claims, characterized in that the stent (9) comprises or forms a receiving space for the occluding means (3).   10. An implantable device according to any one of the preceding claims, characterized in that a timing element is provided for detecting said at least one physiological measurement at predetermined time intervals.   A storage device for storing the physiological measurements and / or occlusion procedure is provided, the storage device being connected to a transmitter for wireless transmission of stored content. 11. The implantable device according to any one of up to 10.   Said sensor (5, 6, 7) is adapted to establish fluid pressure, fluid volume, flow rate, electrical resistance, electrical impedance, cardiac current to establish an electrocardiogram (ECG), and / or, for example, blood oxygen saturation or pH or 12. Implantable device according to any one of the preceding claims, characterized in that it is configured to detect metabolic parameters such as lactic acid content. Occlusion means (3) operable for intermittent occlusion;
A control device (4) connected to the closing means (3);
At least one sensor (5, 6, 7) for continuously or periodically detecting at least one physiological measurement;
A device for intermittently occluding a blood vessel, comprising: a measured value storage device configured to receive a measured value from the sensor and store a measured value series;
The measurement value sequence is supplied to the control device (4), the control device (4) is configured to calculate the measurement value sequence, and in cooperation with the blocking means (3) apparatus characterized by starting or end in accordance with the evaluation results intermittent occlusion.   14. Device according to claim 13, characterized in that the control device (4) is configured to perform a calculation evaluation after each measurement value determination.   14. The control device (4), comprising a conversion circuit for converting individual measurement values of the measurement value series into converted measurement values so as to obtain a converted measurement value series. Or the apparatus of 14.   The control device (4) provides the difference between the last two measured values of each of the measured value series or the last two converted measurements of each of the converted measured value series so that a set of difference values is obtained. The apparatus according to claim 15, wherein the apparatus is configured to determine a difference in values.   17. The device according to claim 16, characterized in that the control device (4) is arranged to determine the cumulative difference of the set of difference values. Wherein the controller (4), as the derivative sequence is obtained, the measured value of the measurement value sequence, or in the converted measured value of the obtained measurement value sequence, to determine changes per time unit The apparatus according to claim 15, wherein the apparatus is configured as follows. Wherein the control unit (4) is a value of the measured value series and or the post-conversion measurement value sequence, to determine the pole Daine (15) and / or a minimum value, and the maximum value (15) or minimum value 16. Device according to claim 15 , characterized in that it is arranged to form a series of extreme values (16, 17, 18, 19) from each. The control device (4) determines a maximum value (15) and / or a minimum value of the values of the measurement value series and / or the difference value series, and a series of values from the maximum value (15) or the minimum value, respectively. Device according to claim 16, characterized in that it is arranged to form extrema (16, 17, 18, 19). The control device (4) determines a maximum value (15) and / or a minimum value of the values of the measurement value series and / or the derivative series, and a series from each of the maximum value (15) and the minimum value. The device according to claim 18, characterized in that it is configured to form an extreme value of (16, 17, 18, 19). The control device (4) is configured such that the maximum value (20) or the minimum value (21) of the value respectively occurring during the occlusion is selected as the maximum value or the minimum value, respectively. An apparatus according to any one of claims 19 to 21 . Control device (4) is, the measurement value sequence, a value of the converted measured value based Retsu及 beauty / or extreme-series, a comparator circuit for comparison with a given limit value, the limit value 23. A device according to claim 15, 19 or 22 , characterized by cooperating with the occlusion means to initiate the intermittent occlusion when achieved. The control device (4) includes a comparison circuit for comparing the measured value series, the difference value series and / or extreme value series, and / or the value of the cumulative difference with a given limit value, 23. A device according to claim 16, 17, 20 or 22, characterized by cooperating with the occlusion means to initiate the intermittent occlusion when a value is achieved . The control device (4) comprises a comparison circuit for comparing the values of the measured value series, the derivative series and / or the extreme value series with a given limit value, and the intermittent means is reached when the limit value is achieved. 23. A device according to claim 18, 21 or 22, characterized by cooperating with the closure means to initiate a closure. Wherein the control unit (4) is, the measurement value sequence, the post-conversion measurement sequence, is configured to recognize or estimate flop plateau value of the values of 及 beauty / or the extreme sequence, when achievement of the plateau value 24. Cooperating with the occlusion means to end the intermittent occlusion at a predetermined percentage of the plateau value, according to claim 15, 19, 22, or 23 . apparatus. The control device (4) is configured to recognize or estimate a plateau value of the values of the measurement value series, the difference value series, and / or the extreme value series, and when the plateau value is achieved or the plateau value 25. A device according to claim 16, 20, 22 or 24, wherein said device cooperates with said occlusion means to terminate said intermittent occlusion at a predetermined percentage. The control device (4) is configured to recognize or estimate a plateau value of the measured value series and / or the derivative series and / or the extreme value series, and when the plateau value is achieved or 26. A device according to claim 18, 21, 22 or 25, wherein the device cooperates with the occlusion means to terminate the intermittent occlusion at a predetermined percentage of the plateau value. . 14. The control device (4) according to claim 13, characterized in that it cooperates with the closing means such that a new measurement series is started respectively at the start and / or end of the intermittent closure. 30. Apparatus according to any one of claims 28 to 28 . Said sensor (5, 6, 7) is, blood pressure within said vessel (2), said vessel (2) Subdivision zone in blood mass or volume flow rate that put the, electrical resistance, electrical conductivity, before Symbol vessels ( electrical impedance of the section of 2), E CG, and / or, characterized in that it is configured to detect metabolic parameters, according to any one of claims 13 to claim 28 apparatus. Device according to any one of claims 13 to 30 , characterized in that the sensor comprises an electrode (6) for generating a current pulse. 32. Apparatus according to any one of claims 13 to 31 , characterized in that an evaluation circuit is provided for evaluating ECG. Wherein the control unit (4) is, the blood vessel (2) of the said measured values determined during closure of each separately calculated evaluation, the closure means to end the closure according to the evaluation result (3 The device according to any one of claims 13 to 32 , characterized in that it cooperates with Wherein the control unit (4) is, the blood vessel (2) to evaluate calculate solutions the measurement values determined in relief each separately of the closure means to start the closure according to the evaluation result (3 34. The device according to any one of claims 13 to 33 , characterized in that it cooperates with The sensor is configured as a blood pressure sensor (5), positionable in the blood vessel to be occluded, and the control device cooperates with the occlusion means to release the occlusion when a limit value is achieved; 35. Apparatus according to any one of claims 13 to 34 , characterized in that 36. Device according to any one of claims 13 to 35 , characterized in that the blood vessel (2) is a coronary sinus. 37. The device according to any one of claims 13 to 36, characterized in that the device is designed as an implantable device according to any one of claims 1 to 13. apparatus. The implantable device of claim 1, wherein the blood vessel is a vein exiting an organ system. The implantable device of claim 2, wherein the closure means is electrically actuatable. 14. The implantable device of claim 13, wherein the blood vessel is a vein that exits the organ system. The implantable device of claim 13, wherein the calculation is a statistical evaluation. 31. The implantable according to claim 30, wherein electrical impedance is the electrical impedance of the region of the blood vessel in the heart and / or lung, and the metabolic parameter is oxygen saturation and / or lactic acid content or pH. Equipment.

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