Devices and methods for determining cardiac function in living organisms

Abstract

We present systems, methods, and algorithms for determining cardiac pump function. [Solution] Medical catheters, sheaths, and shafts house an integrated digital sensor system on a chip (SoC) within their parts present in the body. These devices combine a complete chain of signal conversion, analog-to-digital signal conversion, and digital signal transmission within the body-present parts of the device, enabling the acquisition of single and multiple physical emitters within a single setup. The devices incorporate wireless data transfer functionality, and in certain examples, the devices incorporate wireless energy harvesting for battery-free functionality. Further, we describe auxiliary monitoring systems suitable for receiving, processing, and analyzing data acquired by such catheters / sheaths / shafts to provide a robust assessment of cardiac performance.

Description

Background Art

[0001] The pumping action of the heart is a fundamental vital function of the body, and its accurate determination is important in many medical conditions, sports, and other fields of application. The determination of cardiac output is defined as the integrated forward flow of blood from the left ventricle over a given time interval and is correlated in a highly non-linear fashion with various measurable biological parameters. This correlation is further affected by the presence and activity of artificial devices, such as heart assist pumps, at various locations in the circulatory system. There are several clinical measurement techniques for cardiac pump function, such as cardiac catheterization, thermodilution, and pulse wave analysis, but all methods have specific limitations such as inaccuracy, ineffectiveness, invasiveness, and practical difficulties in clinical applications.

[0002] Need for a New Catheter The determination and monitoring of cardiac performance, particularly cardiac output, often rely on the evaluation of a single important physiological parameter obtained as a surrogate for the (inaccessible) cardiac output parameter of interest.

[0003] Typically, the measurement of parameters for calculating cardiac output (CO) relies on invasive catheters. Such catheters often include fluid lines that transmit pressure within the body to sensors outside the body, or consist of optical lines that transmit optical signals from measurement locations within the body to sensors outside the body, or include electrical lines that transmit analog signals from within the body (e.g., from a thermistor) to an analog / digital converter outside the body. The transmission of physical or analog signals from within the body to transducers outside the body is susceptible to mechanical or electrical noise, such catheters are often difficult and expensive to manufacture, catheter handling in clinical practice requires effort, and the multiple connections (analog wires, fluids) and external power sources and signal transfer lines required for functionality make patient management more complex.

[0004] Therefore, future systems for determining cardiac output should innovate catheter designs to overcome these limitations.

[0005] Using a single parameter to determine cardiac output, as is typically done using thermodilution or extrapulse analysis, has several drawbacks, including the following: 1) Alternative parameters cannot accurately represent necessary but inaccessible cardiac function parameters. 2) Alternative values ​​may be confused by other physiological and technical parameters. 3) Relying on a single sensor makes this method sensitive to sensor errors such as noise, drift, sensor inaccuracy, and sensor displacement. 4) Cardiac support systems, whether implanted, external, or percutaneous catheter-based, are typically a major confounding factor in the algorithms currently used to calculate cardiac output (CO).

[0006] The need for multiple parameters and integrated analysis of these parameters In contrast, cardiac function determination methods based on combinations of multiple biological signals may overcome the aforementioned weaknesses to some extent by delivering a more robust primary signal and allowing control over confounding factors. One significant practical limitation of current clinical practice when monitoring multiple vital parameters is that it results in increased complexity in patient management, typically because each additional sensor is accompanied by its own cable for power and signal output, thereby increasing complexity and cost.

[0007] Therefore, preferably, future systems for determining cardiac output should have the ability to a) acquire multiple signal modalities in a synchronized manner with minimal equipment, b) combine and analyze multiple signal parameters, and c) be applicable and reliable to patients receiving mechanical circulatory support.

[0008] This suggests the need for innovation in cardiac monitoring devices and algorithms used with catheters / sheaths / shafts in the present invention.

[0009] prior art The most advanced monitoring catheters currently available can explore a single physical modality within the body, which in a typical scenario is guided outside the body, where an external transducer converts the physical signal into an analog signal, and the analog signal is then converted into a digital signal in a further step. A typical example is the current invasive pressure monitoring catheter.

[0010] In addition, there are medical pressure wires that can be placed inside the body to measure a single signal. These medical pressure wires convert pressure at the wire tip by converting pressure inside the body into an analog signal, and guide this analog signal to a catheter portion outside the body. This device needs to be connected to a second device (interface box) outside the body for analog / digital signal conversion and data transmission (Radi patent, 1997, patents.justia.com / patents / 6112598), (see Volcano patent, 2002, http: / / patents.justia.com / patent / 6976965). There are also medical Doppler wires that allow for the extraction of a single ultrasonic Doppler signal from the body by reading not only low-frequency pressure but also high-frequency pressure oscillations via a similar catheter. In this case, the analog signal is guided from the catheter tip to an external location where further equipment is required for analog / digital conversion (see Volcano patent, 2002, http: / / patents.justia.com / patent / 6976965). In addition, a limited number of internal medicine multimode sensing catheters exist, which typically have an analog sensing element and several channels of fiber guiding physical signals (pressure, light) from the body that are converted into electrical signals outside the body. One example is the CCOmbo / SvO2 pulmonary artery catheter from Edwards Life Science. The CCOmbo / SvO2 pulmonary artery catheter combines an analog temperature-sensing thermistor at the tip of the catheter inside the body, a fluid-filled lumen that allows pressure determination outside the body, an additional external pressure transducer, and optical fibers that guide the optical spectrum outside the body, thereby the actual optical sensor that converts the physical signals into a stream of digital information is located outside the body.

[0011] Prior art for monitoring cardiac output, the main method currently in use is the pulmonary artery catheter, and the PiCCO system and pulmonary morphology are the main components of prior art.

[0012] a) Details of Pulmonary Artery Catheterization: Pulmonary artery catheterization has long been considered the mainstay of cardiac output monitoring in clinical practice, although it is well known to be inaccurate in various situations. The simplest pulmonary artery catheterization measures the temperature curve within the pulmonary artery after injecting a cryogenic fluid into the right atrium. Pulmonary artery catheterization is often difficult to place and carries a risk of infection and pulmonary artery injury, especially when tricuspid (heart) valve insufficiency is present, as in the most critically ill patients, and has a large variability in measurements. An alternative Fick method for determining cardiac output relies on the oxygen content of blood drawn from the pulmonary artery via pulmonary artery catheterization and in the arterial circulation. This method is unreliable because it relies on knowledge of systemic oxygen consumption (which typically varies in patients). Yet another method is continuous monitoring of central venous oxygen saturation using a catheter equipped with an optical fiber. This parameter is not considered a good substitute for cardiac output because it depends on many confounding factors unrelated to cardiac output. All of these pulmonary artery catheter-based methods are old, and multiple expired patents cover them.

[0013] b) Details of the PiCCO system: The PiCCO system relies on bolus thermodilution measurement in the central artery after injection of a cryogenic fluid bolus into the central vein, and therefore requires a separate central vascular catheter. Technically, the PiCCO system consists of a thermistor on the tip of the catheter, an external signal digitizer, and data transmission in a separate external module. In addition, PiCCO can use the shape of blood pressure guided out of the central artery through a fluid-filled lumen, thereby monitored using an external pressure transducer, followed by an external analog / digital converter and data transmission.

[0014] c) HighDim prior art (U.S. Patent Application No. 13 / 827,063) describes an apparatus and method for calculating cardiac output based on multi-parameter physiological data analyzed using multidimensional nonlinear optimization to calculate cardiac output. A limitation of this method is that it does not consider cases where circulatory support devices, such as implantable heart pumps, contribute to an individual's cardiac output. In such cases, the true cardiac output is underestimated because the contribution of the machine is not taken into account. Furthermore, implantable heart pumps induce changes in the circulatory system, which are not taken into account in the algorithm learning process described in (U.S. Patent Application No. 13 / 827,063).

[0015] Improvements in medical monitoring technology are desirable because innovation can lead to improved patient management.

[0016] Measuring multiple physical signals at different locations within the body can provide information suitable as input for algorithms and systems that can leverage the supplemental, redundant, and interdependent informational content of these signals, as described below.

[0017] Definition of Terms The expression "inside the body" shall, by extension, encompass any setting in which a medical invasive device is inserted, either entirely or precisely, into one of the following: blood vessels, body cavities, and body tissues.

[0018] A catheter is a hollow tube with a diameter of less than 1 centimeter and more than 100 micrometers, whose primary function is to connect a body compartment (typically an intravascular compartment) to the outside of the body in order to achieve one of the following objectives: injection of therapeutic fluid through a water column guided outside the body, collection of blood, and measurement of hydrostatic pressure.

[0019] A sheath is a hollow tube with a diameter of less than 1 centimeter and more than 100 micrometers that serves to accommodate an elongated internal object within the main lumen of the hollow tube, guiding the elongated internal object from outside the body into the body. Such a sheath may contain zero or more additional hollow lumens for other purposes in addition to the main lumen that carries the object.

[0020] A shaft is defined as an elongated object with a diameter of less than 1 centimeter and more than 100 micrometers, whose primary function is to hold several functional subsystems, including at least one of a pump and a sensor array, within the portion of the shaft that is inside the body. Here, C / S / S is used for "catheter, sheath, shaft".

[0021] A miniaturized digital sensor system-on-chip (SoC) as described herein combines the necessary circuitry to bring about the digital coding of quantitative measurements of a physical modality, including at least signal / analog conversion, analog / digital conversion, and digital transmission, in an integrated package having a diameter measured orthogonal to the device axis, which is no larger than the space available at the target location in the body (typically smaller than 5 square millimeters for catheters and shafts placed only for diagnostic purposes, and typically smaller than 20 square millimeters for sheaths used with heart pumps). The use of such miniaturized digital sensors has the advantages of a) the elimination of transmission of analog signals which are prone to noise and bias, b) a reduction in the number of noise sources due to integrated conversion and digitization sensor elements, c) digital multiplexing of the outputs of multiple sensors enabling a minimum number of signal lines, d) the manufacturing of catheters, sheaths, and shafts is simplified because fewer electrical connections are required, and e) digital sensors exist with very low power requirements. The size limits of these sensors are important because they restrict the clinically acceptable size of access to blood vessels, typically ranging from 0.5 to 3 mm in device diameter for purely diagnostic use, up to 5 mm for shafts of circulatory support devices, and up to 8 mm for catheters used in extracorporeal circulation. The power requirements of the sensors are important for clinical applications and are preferably low to simplify the power supply and avoid clinically undesirable sensor overheating.

[0022] computer In relation to the present invention, the term “computer” can refer to any suitable computing system. In particular, a computer may be a desktop computer, a laptop computer, a tablet, a smartphone, or similar device, as well as an embedded computing system such as a microcontroller or any other single or multiprocessor embedded system.

[0023] Energy harvesting Ambient power generation is used to describe the process by which a device extracts electrical energy from physical energy sources in its surroundings without having a wired connection to an energy source. Ambient power generation technologies are well known to practitioners in the art. In the context of this patent, the term "coil" refers to an electrical coil.

[0024] Heart pump A heart pump is defined as a medical device that pumps blood from one compartment of the blood circulation to another. Typical pumps include: a) an extracorporeal pump having mechanical pump components outside the body; b) a catheter-based pump having mechanical pump components inside the body and attached to the tip of a shaft that crosses the skin; and c) a fully implanted pump having mechanical pump components inside the body and no components except for a power cable that crosses the skin.

[0025] Deep neural network In the field of machine learning, a deep neural network (DNN) is an artificial neural network (ANN) that has multiple hidden layers consisting of multiple units between an input layer and an output layer.

[0026] Deep belief network In the field of machine learning, a deep belief network is a type of deep neural network that includes multiple layers of latent variables that have connections between the layers but no connections between the units within each layer. Summary of the Invention

[0027] According to the present invention, the need for a more accurate measurement of signals that reflect a patient's cardiac performance and enable the extraction of cardiac output parameters that better represent cardiac output is solved by medical invasive devices, and methods and apparatuses for calculating such cardiac output are defined by the features of each independent claim. Preferred embodiments are the subject matter of the dependent claims.

[0028] In particular, the present invention deals with innovative settings for medical invasive devices in which, for example, signal conversion, analog-to-digital signal conversion, and digital signal transmission are transferred into a portion of a catheter configured to be located inside a vascular lumen by using a miniaturized digital sensor SoC.

[0029] Therefore, the medical digital sensor SoC array is attached to the catheter, sheath, and shaft at a location within the body.

[0030] The advantages derived from such an innovative setup include 1) reducing or eliminating the need for an external signal transducer module, thus simplifying industrial production, distribution, and clinical use, and 2) eliminating the need for wires to carry sensitive analog signals and hydrostatic columns for pressure propagation of optical lines for signal transmission. The proposed setup consists of a device in the form of a catheter, sheath, and shaft with a miniaturized digital sensor at its tip, performing the stages of physical signal sensing, signal conversion, analog-to-digital signal conversion, and digital signal transmission at the location where it is placed inside the body.

[0031] Furthermore, numerous sensor SoCs that measure various auxiliary physical signals can be placed within the medical catheter, sheath, and shaft portions configured to be placed inside the body according to the present invention.

[0032] The sensors used in connection with the present invention will be described in more detail below. In line with the innovative settings described above, there are provided medical digital sensor SoCs and SoC arrays in which the sensors are attached to a part of a medical invasive device located inside the body, and thus an integrated multimode sensor array for vital biological signal monitoring can be integrated into one of the following: a) Shaft Circulation Support Device b) A shaft that stands independently c) Sheath across blood vessels d) Intravascular catheter

[0033] Several useful sensor combinations are possible, and non-limiting examples are shown below.

[0034] Integration has the advantage of reducing the number of access cables to the patient to one per sensor array, resulting in improved practicality in clinical scenarios.

[0035] In addition, the device is described below in the form of a medical catheter, sheath, or shaft comprising a digital sensor SoC having digital transmission in a position configured to be placed inside the body, with a digital interface incorporated in a portion configured to be located outside the body, thereby enabling the connection of a connector cable for power and digital data transfer.

[0036] While the embodiments conceivable according to the above aspects of the present invention already simplify and improve medical monitoring, it is still desirable to abandon wired power and communication. For these reasons, further improvements are desirable.

[0037] According to another aspect of the present invention, a wireless transmitting catheter and / or sheath and / or shaft can be designed using an integrated medical sensor SoC and SoC array. Thus, the integrated multimode biomedical sensor array is powered by an integrated battery and can be read out by wireless data transmission.

[0038] Therefore, a further aspect of the present invention comprises a medical catheter, sheath, and shaft, and in a single embodiment, a miniaturized digital sensor SoC device located in a portion configured to be located inside the body is combined with a wireless communication chip and a miniaturized battery located in a portion configured to be located outside the body. This eliminates the need for cables for power and communication, greatly improving clinical practicality. Furthermore, since no metal connection to the patient is required, it improves electrical safety.

[0039] According to further possible embodiments of the present invention, medical catheters, sheaths, and shafts can be designed with connectors combined with a pluggable module that includes a miniaturized digital sensor device configured to be positioned inside the body, and a small battery and electronics for wireless signal transmission.

[0040] This has the advantage of allowing you to replace an empty battery by plugging in a charged replacement module.

[0041] From the spectra with a large potential sensor modality that can be used as elements for the sensor array according to the present invention, the following are preferred: - A miniaturized digital pressure sensor SoC is beneficial because it enables the measurement of blood pressure (an important parameter of cardiac function) at a given location, but, in contrast to conventional sensors, it does not require a fluid-filled pressurized access channel or an extracorporeal transducer typically used in conventional pressure monitoring catheters, and does not rely on analog signal transmission along the device. A preferred example of a miniaturized digital temperature sensor is beneficial because it enables the monitoring of body temperature and also enables the measurement of temperature fluctuations that occur after the injection of a cold fluid bolus, the characteristics and timing of such temperature fluctuations after such thermal bolus injection are relevant to cardiac performance. - Miniaturized digital light-emitting elements and receivers for multiple wavelengths make it possible to determine the spectral components of blood, and thus obtain blood oxygenation using a standard method, and it is well known that blood oxygenation and the time course of blood oxygenation contain relevant information about cardiopulmonary function. - Miniaturized digital vibration sensors can sense the dynamic turbulence patterns of blood flow, thereby allowing the information to be used to improve cardiac function. - Ultrasonic Doppler sensors enable the measurement of blood flow velocity, thereby contributing information to cardiac function. - Direct ultrasonic flow sensors enable the determination of wave velocity between multiple points, thereby directly measuring blood flow velocity and contributing to information about cardiac function. - Voltage sensors enable direct detection of the timing and frequency of electrical cardiac activity, and allow for the measurement of local body impedance.

[0042] While the above improvements surpass those of prior art, improving patient management, it would be even more desirable to eliminate the need for batteries altogether, as these improvements could simplify manufacturing, improve shelf life, reduce costs, and decrease the risk of battery leakage. Therefore, further innovation is desirable.

[0043] In a further embodiment of the present invention, a device in the form of a medical catheter, sheath, and shaft, comprising a digital sensor SoC in a portion configured to be located inside the body and wireless transmission electronics in one of a portion configured to be located outside the body and a pluggable module, is further equipped with an energy transfer and power generation mechanism that eliminates the need for power via a battery or cable. A battery-free energy harvesting medical sensor array is described in combination with a catheter, sheath, and retaining shaft. Battery independence can result in a more compact design and improved practicality, as battery discharge is no longer an issue.

[0044] Recent advances in wireless technology have made it possible to manufacture battery-powered wireless sensors, thus reducing the need for cables.

[0045] Recent advances in energy harvesting have made it possible to extract energy from environmental sources such as electromagnetic fields, sunlight, vibrations, and heat.

[0046] The following energy harvesting mechanisms may be used: a) inductive energy transfer via electromagnetic fields, b) capacitive energy transfer, c) solar cell-based energy transfer, d) energy harvesting by vibration, and d) thermoelectric energy conversion. The preferred version is inductive energy transfer, as it can typically transfer greater energy compared to other setups, but does not require high voltage on the energy transfer device side.

[0047] Furthermore, the present invention deals with algorithms that combine vital signals, technical control signals, and motor parameters, and discloses novel combinations that go beyond the latest known multi-parameter biosignal monitoring, combining them with technical control signals and performance signals originating from catheter-based or implantable circulatory pumps. This has the practical advantage of making biosignal analysis applicable to patients with catheter-based or implantable circulatory support devices.

[0048] The present invention also addresses methods used with multi-parameter signals, suitable for patients with and without cardiac support devices.

[0049] One method combines several physiological data sources and several parameters obtained from cardiac support devices to construct a nonlinear mathematical model that correlates these data to a target cardiac output value. Physiological data vectors include one or more measurable or obtainable parameters such as systolic and diastolic pressure, pulse pressure, heart rate interval, mean arterial pressure, maximum slope of pressure rise during systole, area below the systolic portion of the pulse pressure wave, sex (male or female), age, height, weight, and diagnostic class. Parameters obtained from cardiac support devices include one or more of the following: device blood flow, device type, device performance settings, motor current, rotation frequency, device internal pressure, and inter-device pressure. Target cardiac output values ​​are obtained across multiple individuals using various methods.

[0050] Next, multidimensional nonlinear optimization is used to find a mathematical model that transforms the source data into target CO data. The model is then applied to individuals by acquiring physiological data about them and applying the model to the collected data.

[0051] The step involves adding cardiac assist device parameters to physiological parameters in order to build a model. In contrast to what was done in the prior art, the present invention achieves more robust results by using joint biological and assistive device information. While the assistive device acted as a confounding factor using the setup described in the prior art, in the present invention, mechanical parameters are now a useful source of information. In practice, this expands the patient spectrum to which such monitoring can be applied.

[0052] In another embodiment, the same biological parameters (preferably blood pressure and its time course) are measured at two different locations within the same compartment of the circulation. The advantage of this technique is that pulse wave propagation, a highly nonlinear biological process, can enter the mathematical model as additional information, thereby making the mathematical model more robust. In contrast, ignoring pulse wave propagation, as is done in normal clinical practice, has made pulse wave propagation a confounding factor for cardiac output analysis.

[0053] The present invention further discloses a monitor designed to enable the determination of the aforementioned cardiac performance based on a combination of medical signals and motor control / performance signals, - A system for monitoring vital signs based on a combination of catheters, sheaths, and shafts equipped with a medical sensor SoC, optional wireless data transmission, optional wireless energy harvesting, and a monitor suitable for multimode signals. - Use of a system that combines biosignals and motor parameters for patient monitoring. - Use of wireless sensor array data transmission for patient monitoring - Use of energy harvesting catheters, sheaths, and shafts for patient monitoring - Use of a system that combines wireless medical sensor arrays for patient monitoring We will also disclose this.

[0054] The medical invasive device according to the present invention is used in conjunction with the method for calculating the cardiac output of a living organism according to the present invention, and is described in more detail below in this specification with reference to the accompanying drawings, by exemplary embodiments. [Brief explanation of the drawing]

[0055] [Figure 1] This is a cross-sectional view of one embodiment of a medical invasive device according to the present invention. [Figure 2] This is a side view of one embodiment of a medical invasive device according to the present invention. [Figure 3] This figure shows one embodiment of a sheath having an integrated flexible electronics substrate and a receiving coil circuit, and one embodiment of a shaft having an integrated emitter coil circuit according to the present invention. [Figure 4] This is a diagram of one embodiment of a sheath (outer element) that covers a segment of a coaxial shaft (inner element) according to the present invention. [Modes for carrying out the invention]

[0056] Sensor Catheter: In one embodiment of the catheter, sheath, and shaft according to the present invention, a standalone monitoring catheter is constructed from a polymer molded product having an internal lumen of 0.018” (intended for a guidewire) and an outer diameter of 2.8 mm, smaller than that of a current pulmonary artery catheter sheath. Housed within the polymer molded product is a flexible electronics substrate from polymer having a diameter of 2.4 mm and a length of 15 mm, connecting the in-body and out-of-body portions of the device. The in-body portion of the flexible substrate holds two digital sensors, namely a digital pressure sensor and a digital temperature sensor, in one miniaturized package, and is packed with analog / digital conversion and digital signal transmission integrated into a single plastic body of 2 × 2 × 0.76 mm (STMicroelectronics, part Nr. LPS22HB), while the out-of-body portion of the flexible electronics substrate holds a connector for wired readout.

[0057] Wireless Sensor Catheter: In one embodiment of the catheter, sheath, and shaft according to the present invention, a standalone monitoring catheter is constructed from a polymer molded product having an internal lumen of 0.018” (intended for a guidewire) and an outer diameter of 2.8 mm, smaller than that of a current pulmonary artery catheter sheath. Housed within the polymer molded product is a flexible electronics substrate from polymer having a diameter of 2.4 mm and a length of 15 mm, connecting the in-body and out-of-body portions of the device. In the in-body portion, the flexible substrate holds two digital sensors, namely a digital pressure sensor and a digital temperature sensor, in a single miniaturized package, and is packed with analog / digital conversion and digital signal transmission integrated into a single plastic body of 2 × 2 × 0.76 mm (STMicroelectronics, part Nr. LPS22HB), while in the out-of-body portion, the flexible electronics substrate holds a miniature chip with digital communication and wireless transmission (TI) and a miniature battery (type).

[0058] For energy harvesting to work, the energy acquired over time must be sufficient to power the sensor at the desired measurement interval (typically ranging from 10 milliseconds to 4 hours) and to power wireless transmission at the desired transmission interval (typically ranging from 100 milliseconds to 4 hours).

[0059] An external electromagnetic field needs to be created for inductive wireless power supply to the device. Requirements for this electromagnetic field include safety, sufficient energy transfer capability, and compliance with existing regulations. We have identified several design variations as follows:

[0060] 1) A custom-designed energy receiving coil on the catheter, sheath, and shaft, along with a matched emitter coil having a similar resonant frequency, is constructed and optimized so that the received energy is sufficient to drive the electronics integrated into the catheter, sheath, and shaft. An example of such a setup is shown in the examples. In a suitable setup, such a combination operates within the high-frequency band legally permitted for medical use, at a certain distance from the energy emitter to the energy receiver (e.g., 30-50 cm from the catheter insertion site), and such a combination is suitable for bedside applications.

[0061] 2) The emission field is generated near the patient's bed by the emitter. Such energy transmission is well known in the industry and is described in detail, for example, in ISO standard 15693, and allows for energy and data transmission up to 1 to 1.5 meters. The advantage of this solution is that a clinically desirable distance from the patient is maintained and patient care is made easier, while the disadvantage of this solution is that the transmitted energy is low, typically allowing only very limited functionality of the electronics on the receiving device.

[0062] 3) The emission field is generated by a transmitter placed near the exit point of the device in the skin (up to 10 cm). The transmission of energy and data is well known in the industry and is described in detail in ISO Rule 14443. The advantage of the short distance is that energy generation at the receiver side is improved, thereby enabling more functionality at the device side. The disadvantage is that the emitter coil at this distance from the patient may interfere with patient care, and this setup requires that the emitter coil remain close enough over time.

[0063] 4) The emission field is generated by a transmitter according to a wireless charging standard, such as the Qi standard. While the Qi standard was originally designed for high-current charging with devices like mobile phones placed close (a few centimeters) to the emission coil, we found that we could use an improved setup that allows for the transfer of smaller amounts of energy over larger distances (up to 1 meter). The amount of energy transferred is much smaller (attenuating approximately with respect to the cube of the distance), but this is still sufficient for the very low-power electronics used in our setup.

[0064] 5) The discharge field is generated by the catheter across the sensor-equipped sheath. This scenario is suitable when using the sensor-equipped sheath to guide the shaft of a circulatory support device into the body, thus ensuring proximity between the discharge coil and the sensor-equipped device and optimizing energy transfer. An example of this setup in operation is shown below.

[0065] Other standards that follow the radio interaction standards for energy and information transmission, such as EPC standards, differ in frequency band, data transmission protocol, and other details, but can be used wherever specific requirements allow.

[0066] All are optional, and typically, higher frequencies allow the desired resonant frequency to be achieved with lower inductance coils and smaller capacitors, thus simplifying the design of the emitter and receiver coils.

[0067] Radioenergy Transfer / Harvesting: In several experiments, energy harvesting using coils incorporated into our catheters, sheaths, and shafts was tested. To achieve this objective, a copper wire receiving coil (200 micrometer copper wire, 25 turns, coil diameter 4 mm, coil length 85 mm, inductance 0.384 microhenries evaluated by resonance tuning) was incorporated into a sheath (molded polydimethylsiloxane). A resonant circuit was generated by connecting a 1 nanofarad capacitor in parallel with the receiving coil. Resonance in the receiving circuit was observed at a frequency of 8.12 MHz.

[0068] In addition, the energy transmitting coil was constructed from 200 micrometer copper wire, 30 turns, with a coil diameter of 2 mm and a coil length of 150 mm, and had a measured inductance of 0.377 microhenries. The transmitting coil was placed inside the shaft of a catheter-assisted cardiac device. The resonant circuit was generated by connecting a 1 nanofarad capacitor in parallel with the emitter coil. Resonance of the emitter circuit was indeed observed at the same resonant frequency (8.2 MHz) as the receiving circuit. The shaft was inserted into the sheath so that the emitter coil was coaxial with respect to the receiving coil. The emitter circuit, connected in series with a 100 ohm current-limiting resistor, was driven by a sinusoidal signal at a frequency of 8.12 MHz and an amplitude of 10 V generated by a waveform generator (Hewlett-Packard 33120A). The receiving circuit was connected in series with a diode TS4148 used for rectification. The rectified signal was fed to a voltage regulator constructed based on a step-down DC-DC converter from Texas Instruments LM3671.

[0069] The successful energy transfer from the emitter circuit to the receiver circuit was recorded as follows: The voltage across a 1-kilohm resistive load connected to the output of the voltage regulator was 3V, corresponding to a current of 3mA and a power of 9mW. According to the specifications of the LPS22HB pressure and temperature sensor, as well as the specifications of the NRF52832 Bluetooth low-energy (LE) IC from Nordic Semiconductor, this power is sufficient for acquiring pressure and temperature signals, and for transmitting the acquired data to a remote Bluetooth LE device.

[0070] These results demonstrated that sufficient energy could be transferred to the energy harvesting system (the catheter holding the sensor).

[0071] Wireless energy transfer / harvesting In one embodiment of the catheter, sheath, and shaft according to the present invention, a copper wire receiver coil (200 micrometer copper wire, 20 turns, coil diameter 5 mm, coil length 4 mm, inductance evaluated by resonant tuning of 1.57 microhenries) was incorporated into the sheath (molded polydimethylsiloxane). A resonant circuit was generated by connecting a 100 picofarad capacitor in parallel with the receiver coil. Resonance in the receiver circuit was observed at a frequency of 12.76 MHz. An emitter coil was separated from the catheter and constructed from 200 micrometer copper wire, 2 turns, with a coil diameter of 88 mm and a coil length of 4 mm, with an inductance of 1.56 microhenries measured. A resonant circuit was generated by connecting a 100 picofarad capacitor in parallel with the emitter coil. Resonance in the emitter circuit was observed at 12.75 MHz. An emitter circuit connected in series with a 1-kilohm current-limiting resistor was driven by a sinusoidal signal generated by a waveform generator (Hewlett-Packard 33120A) at a frequency of 12.76 MHz and an amplitude of 10 V. An SMD1206 red LED was connected in parallel with the receiver circuit. The successful energy transfer from the emitter circuit to the receiver circuit was recorded as follows: When the emitter coil was placed close to the receiving coil (at a distance of 1-3 mm), the LED began to glow and showed an utilization of at least several hundred microwatts of acquired power, according to the LED's specifications.

[0072] Wireless Energy Harvesting Sensor Catheter: In one embodiment of the catheter, sheath, and shaft according to the present invention, the access sheath for a cardiac assist device by catheter is constructed from a polymer molded product and has an internal open lumen of 2.8 mm and an outer diameter of 4 mm to accommodate the size requirements for the access sheath of a cardiac assist device. Housed within the polymer molded product is a flexible electronics substrate from polymer having a diameter of 3 mm and a length of 15 mm, connecting the internal and external parts of the device. In the internal part, the flexible substrate holds two digital sensors, namely a digital pressure sensor and a digital temperature sensor, in one miniaturized package, and analog / digital conversion and digital signal transmission are packed into a single plastic body of 2 × 2 × 0.76 mm (STMicroelectronics, part Nr. LPS22HB), while in the external part, the flexible electronics substrate holds a miniaturized chip including digital communication, wireless transmission, and energy harvesting (TI).

[0073] This disclosure also includes the following further embodiments.

[0074] Embodiment 1 is a medical invasive device having a main body configured to be inserted into one of a blood vessel, a body cavity, and body tissue, and is equipped with an electronic circuit and incorporates a sensor device and a digital data transmission device into the main body.

[0075] Embodiment 2 is the same medical invasive device as in Embodiment 1, but with an analog / digital conversion device in its main body.

[0076] Embodiment 3 is a medical invasive device according to Embodiment 1 or Embodiment 2, wherein the medical invasive device has an outer portion configured to be placed outside the body.

[0077] Embodiment 4 is a medical invasive device according to any one of Embodiments 1 to 3, wherein the electronic circuit comprises a sensor device having a temperature sensor, a pressure sensor, a vibration sensor, an ultrasonic sensor, a light sensor, a voltage sensor, or any combination thereof.

[0078] Embodiment 5 is a medical invasive device according to any one of Embodiments 1 to 4, wherein the sensor device comprises at least two sensors for measuring different physical signals.

[0079] Embodiment 6 is a medical invasive device according to any one of Embodiments 1 to 5, wherein the sensor device comprises at least three sensors for measuring different physical signals.

[0080] Embodiment 7 is a medical invasive device according to any one of Embodiments 1 to 6, wherein the medical invasive device has a shaft, which is an elongated object configured to hold the main body and to cross the height of the skin.

[0081] Embodiment 8 is a medical invasive device according to any one of Embodiments 1 to 7, wherein the medical invasive device is a catheter, which is an elongated object configured to fit inside a body and to have several fluid columns.

[0082] Embodiment 9 is a medical invasive device according to any one of Embodiments 1 to 8, wherein the medical invasive device is a sheath, which is an elongated object configured to guide one of a catheter, a treatment device shaft, and a heart pump shaft.

[0083] Embodiment 10 is a medical invasive device according to any one of Embodiments 1 to 9, wherein the main body has a cross-sectional area of ​​less than 60 square millimeters.

[0084] Embodiment 11 is a medical invasive device according to any one of Embodiments 1 to 10, wherein the main body has a cross-sectional area of ​​less than 20 square millimeters.

[0085] Embodiment 12 is a medical invasive device according to any one of Embodiments 1 to 11, wherein the main body has a cross-sectional area of ​​less than 5 square millimeters.

[0086] Embodiment 13 is a medical invasive device according to any one of Embodiments 1 to 12, wherein the electronic circuit comprises a wireless data transmission unit.

[0087] Embodiment 14 is a medical invasive device according to any one of Embodiments 3 to 13, wherein the outer portion comprises a wireless data transmission unit.

[0088] Embodiment 15 is a medical invasive device according to Embodiment 14, wherein the wireless data transmission unit is detachable from the base of the outer portion.

[0089] Embodiment 16 is a medical invasive device according to any one of Embodiments 1 to 15, which is powered by either a battery or a capacitor.

[0090] Embodiment 17 is a medical invasive device according to any one of Embodiments 3 to 16, wherein the battery or capacitor is removable from the outer portion.

[0091] Embodiment 18 is a medical invasive device according to any one of Embodiments 1 to 17, wherein the electronic circuit comprises a power generation unit configured to obtain energy from an energy source not connected to the medical invasive device by wires.

[0092] Embodiment 19 is a medical invasive device according to any one of Embodiments 3 to 18, wherein the outer portion holds a power generation unit.

[0093] Embodiment 20 is a medical invasive device according to Embodiment 19, wherein the power generation unit comprises a coil for acquiring electromagnetic energy.

[0094] Embodiment 21 is a medical invasive device according to Embodiment 19 or 20, wherein the power generation unit comprises a solar cell.

[0095] Embodiment 22 is a medical invasive device according to any one of Embodiments 18 to 21, wherein the power generation unit comprises a vibration-generating generator.

[0096] Embodiment 23 is a medical invasive device according to any one of Embodiments 18 to 22, wherein the power generation unit comprises a thermoelectric generator.

[0097] Embodiment 24 is a medical invasive device according to any one of embodiments 1 to 23, comprising a power generation unit having a receiving coil circuit which is tuned to a frequency such that the electromagnetic field generated in close proximity induces energy transfer to a coil which is sufficient to drive the electronic circuit in the main body and optionally any other electronic circuit of the medical invasive device.

[0098] Embodiment 25 is a medical invasive device according to any one of Embodiments 1 to 24, comprising a power generation unit having a receiving coil circuit configured to generate energy from an electromagnetic field, wherein the field is generated by several emitting coil circuits, and the emitting coil circuits have a resonant frequency within 10% of the resonant frequency of the receiving coil circuit, preferably within 1% of the resonant frequency of the receiving coil circuit, and particularly preferably within 0.1% of the resonant frequency of the receiving coil circuit.

[0099] Embodiment 26 is a medical invasive device according to any one of Embodiments 1 to 25, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 5.725 to 5.875 GHz.

[0100] Embodiment 27 is a medical invasive device according to any one of Embodiments 1 to 26, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 2.4 to 2.5 GHz.

[0101] Embodiment 28 is a medical invasive device according to any one of Embodiments 1 to 27, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 902 to 928 MHz.

[0102] Embodiment 29 is a medical invasive device according to any one of Embodiments 1 to 28, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 13.553 to 13.567 MHz.

[0103] Embodiment 30 is a medical invasive device according to any one of Embodiments 1 to 29, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 6.765 to 6.795 MHz.

[0104] Embodiment 31 is a medical invasive device according to any one of Embodiments 1 to 30, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band (defined by the Power Matters Alliance (PMA)) ranging from 235 to 275 kHz.

[0105] Embodiment 32 is a medical invasive device according to any one of Embodiments 1 to 31, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 110 to 205 kHz (a band defined by the Wireless Power Consortium (WPC)).

[0106] Embodiment 33 is a kit comprising an outer element which is a sheath as described in any one of Embodiments 9 to 32 and an inner element which is a shaft or catheter having a coil circuit, wherein the outer element covers at least one segment of the inner element.

[0107] Embodiment 34 is the kit according to Embodiment 33, wherein the inner element is configured to be coaxial with respect to the outer element.

[0108] Embodiment 35 is the kit according to Embodiment 33 or 34, wherein the inner coil is configured to transmit energy to the outer element.

[0109] Embodiment 36 is the kit according to Embodiment 35, wherein the inner coil is configured to receive data from the outer element by wireless transmission.

[0110] Embodiment 37 is a kit according to any one of embodiments 33 to 36, wherein the outer coil is configured to receive data from the inner element by wireless transmission.

[0111] Embodiment 38 is the kit according to any one of embodiments 33 to 37, wherein the internal element is the shaft of a percutaneous cardiac pump.

[0112] Embodiment 39 is a method for calculating the cardiac output (CO) of a living organism, in which a mathematical model is constructed that links an input data vector with a target CO value.

[0113] Embodiment 40 is the method according to Embodiment 39, wherein the mathematical model is nonlinear.

[0114] Embodiment 41 is the method according to Embodiment 39 or 40, wherein the input data vector comprises at least one sensor measurement obtained by a medical invasive device described in any one of Embodiments 1 to 32.

[0115] Embodiment 42 is a method according to any one of Embodiments 39 to 41, wherein the input data vector includes physiological input source data from the living organism.

[0116] Embodiment 43 is the method according to any one of Embodiments 39 to 42, wherein the input data vector includes the area below the curve of repeated temperature measurements.

[0117] Embodiment 44 is the method according to any one of Embodiments 39 to 43, wherein the input data vector includes the area below the curve of repeated temperature measurements after a fluid bolus has been injected into the venous circulation, and the injected bolus has a temperature different from the blood temperature.

[0118] Embodiment 45 is a method according to any one of Embodiments 39 to 44, wherein the input data vector includes numerical values ​​obtained from arterial pulse pressure analysis.

[0119] Embodiment 46 is a method according to any one of Embodiments 39 to 45, wherein the input data vector includes a numerical value obtained from arterial pulse pressure analysis, and the numerical value is one of the following: heart rate interval, heart rate, systolic blood pressure, diastolic blood pressure, pulse pressure, peak systolic pressure difference for each time difference, area below the pulse curve, and area below the systolic portion of the pulse pressure wave.

[0120] Embodiment 47 is a method according to any one of Embodiments 39 to 46, wherein the input data vector includes at least one of the systolic pressure of the organism, the diastolic pressure of the organism, and the pulse pressure of the organism.

[0121] Embodiment 48 is the method according to any one of Embodiments 39 to 47, wherein the input data vector includes at least one of the following: the age of the organism, the sex of the organism, the height of the organism, the weight of the organism, and the temperature of the organism.

[0122] Embodiment 49 is a method according to any one of Embodiments 39 to 48, wherein the input data vector includes at least one of the following: type of heart pump, performance setting of heart pump, size of heart pump, blood flow rate of heart pump, rotational speed of heart pump, power consumption of heart pump, current consumption of heart pump, and reading of heart pump pressure sensor.

[0123] Embodiment 50 is the method according to any one of Embodiments 39 to 49, wherein the target CO value is determined by an algorithm that includes the step of determining the area below the temperature curve measured repeatedly at multiple time points.

[0124] Embodiment 51 is the method according to any one of Embodiments 39 to 50, wherein the target CO value is determined by analysis of physiological signals measured by a medical invasive device described in any one of Embodiments 1 to 32.

[0125] Embodiment 52 is a method according to any one of Embodiments 39 to 51, wherein the step of generating the mathematical model includes the step of fitting the input data vector to the target CO value in the least-squares optimal manner.

[0126] Embodiment 53 is a method according to any one of Embodiments 39 to 52, wherein the step of generating the mathematical model includes training an artificial neural network (ANN).

[0127] Embodiment 54 is a method according to any one of Embodiments 39 to 53, wherein the step of generating the mathematical model includes unsupervised learning of a deep neural network (DNN).

[0128] Embodiment 55 is a method according to any one of Embodiments 39 to 53, wherein the step of generating the mathematical model includes supervised learning of a deep neural network (DNN).

[0129] Embodiment 56 is the method according to any one of Embodiments 39 to 55, wherein the step of generating the mathematical model includes training a deep believe network (DBN).

[0130] Embodiment 57 is a method according to any one of Embodiments 39 to 56, comprising the steps of obtaining an input data vector, transforming the input data vector using at least the mathematical model, and expressing the result of the transformation as a CO value in physiological units.

[0131] Embodiment 58 is a method according to any one of Embodiments 39 to 57, comprising the steps of obtaining a plurality of target CO values, generating a mathematical model based on at least a portion of the target CO values, obtaining an input data vector, transforming the input data vector using at least the mathematical model, and expressing the result of the transformation as a CO value in physiological units.

[0132] Embodiment 59 is a device comprising a device for receiving data transmitted by a medical invasive device described in any one of Embodiments 1 to 32.

[0133] Embodiment 60 is the apparatus described in Embodiment 59, wherein data is transmitted wirelessly by the medical invasive device.

[0134] Embodiment 61 is the device according to Embodiment 59 or 60, further comprising a device for receiving data transmitted from a second device and used to derive an input data vector.

[0135] Embodiment 62 is the same device as in Embodiment 61, wherein the second device is a medical monitor defined as a device configured to be placed in the same room as the patient, and comprises a display configured to display the patient's vital signs.

[0136] Embodiment 63 is the device according to Embodiment 61 or 62, wherein the second device is the control device for the heart pump.

[0137] Embodiment 64 is the device according to any one of embodiments 61 to 63, further comprising a device for receiving data transmitted wirelessly from the second device and used for deriving the input data vector.

[0138] Embodiment 65 is a device according to any one of Embodiments 60 to 64, wherein wireless data transmission conforms to one of the WiFi standard, Bluetooth standard, or Ant standard.

[0139] Embodiment 66 is a computer program having a code structure configured to perform the method described in any one of Embodiments 39 to 58 when executed on a computer.

[0140] Embodiment 67 is the device according to any one of Embodiments 59 to 65, which includes the computer program described in Embodiment 66.

[0141] Embodiment 68 is the apparatus described in any one of embodiments 59 to 65 and 67, comprising a display configured to show at least cardiac output (CO).

[0142] Embodiment 69 is the computer program described in Embodiment 66, which is stored on a computer-readable medium.

[0143] Embodiment 70 is a computer program product stored on a machine-readable carrier, which includes program code means that, when executed on a computer, implements the method described in any one of Embodiments 39 to 58.

Claims

1. An invasive medical device having a main body configured to be inserted into one of a blood vessel, a body cavity, and body tissue, wherein the main body is equipped with an electronic circuit and incorporates a sensor device and a digital data transmission device.

2. The medical invasive device according to claim 1, comprising an analog / digital conversion device in the main body.

3. A medical invasive device according to claim 1 or 2, having an outer portion configured to be positioned outside the body.

4. The medical invasive device according to any one of claims 1 to 3, wherein the electronic circuit comprises a sensor device having a temperature sensor, a pressure sensor, a vibration sensor, an ultrasonic sensor, a light sensor, a voltage sensor, or any combination thereof.

5. The medical invasive device according to any one of claims 1 to 4, wherein the sensor device comprises at least two sensors for measuring different physical signals.

6. The medical invasive device according to any one of claims 1 to 5, wherein the sensor device comprises at least three sensors for measuring different physical signals.

7. A medical invasive device according to any one of claims 1 to 6, comprising a shaft which is an elongated object that holds the main body and is configured to cross the height of the skin.

8. A medical invasive device according to any one of claims 1 to 7, wherein the catheter is an elongated object configured to fit inside a main body and to have several fluid columns.

9. A medical invasive device according to any one of claims 1 to 8, the sheath being an elongated object configured to guide one of a catheter, a shaft of a therapeutic device, and a shaft of a heart pump.

10. The medical invasive device according to any one of claims 1 to 9, wherein the main body portion has a cross-sectional area of ​​less than 60 square millimeters.

11. The medical invasive device according to any one of claims 1 to 10, wherein the main body portion has a cross-sectional area of ​​less than 20 square millimeters.

12. The medical invasive device according to any one of claims 1 to 11, wherein the main body portion has a cross-sectional area of ​​less than 5 square millimeters.

13. The medical invasive device according to any one of claims 1 to 12, wherein the electronic circuit comprises a wireless data transmission unit.

14. The medical invasive device according to any one of claims 3 to 13, wherein the outer portion comprises a wireless data transmission unit.

15. The medical invasive device according to claim 14, wherein the wireless data transmission unit is detachable from the base of the outer portion.

16. A medical invasive device according to any one of claims 1 to 15, powered by either a battery or a capacitor.

17. The medical invasive device according to any one of claims 3 to 16, wherein the battery or capacitor is removable from the outer portion.

18. The medical invasive device according to any one of claims 1 to 17, wherein the electronic circuit comprises a power generation unit configured to obtain energy from an energy source not connected to the medical invasive device by electric wires.

19. The invasive medical device according to any one of claims 3 to 18, wherein the outer portion holds a power generation unit.

20. The medical invasive device according to claim 19, wherein the power generation unit comprises a coil for acquiring electromagnetic energy.

21. The medical invasive device according to claim 19 or 20, wherein the power generation unit comprises a solar cell.

22. The medical invasive device according to any one of claims 18 to 21, wherein the power generation unit comprises a generator that operates by vibration.

23. The medical invasive device according to any one of claims 18 to 22, wherein the power generation unit comprises a thermoelectric generator.

24. A medical invasive device according to any one of claims 1 to 23, comprising a power generation unit having a receiving coil circuit which is tuned to a frequency such that the electromagnetic field generated in close proximity is sufficient to induce energy transfer to a coil which is sufficient to drive the electronic circuit in the main body and optionally any other electronic circuit of the medical invasive device.

25. A medical invasive device according to any one of claims 1 to 24, comprising a power generation unit having a receiving coil circuit configured to generate energy from an electromagnetic field, wherein the field is generated by several emitting coil circuits, the emitting coil circuits having a resonant frequency within 10% of the resonant frequency of the receiving coil circuit, preferably within 1% of the resonant frequency of the receiving coil circuit, and particularly preferably within 0.1% of the resonant frequency of the receiving coil circuit.

26. A medical invasive device according to any one of claims 1 to 25, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 5.725 to 5.875 GHz.

27. A medical invasive device according to any one of claims 1 to 26, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 2.4 to 2.5 GHz.

28. A medical invasive device according to any one of claims 1 to 27, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 902 to 928 MHz.

29. A medical invasive device according to any one of claims 1 to 28, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band in the range of 13.553 to 13.567 MHz.

30. A medical invasive device according to any one of claims 1 to 29, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 6.765 to 6.795 MHz.

31. A medical invasive device according to any one of claims 1 to 30, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 235 to 275 kHz.

32. A medical invasive device according to any one of claims 1 to 31, comprising several coil circuits configured to generate energy from an electromagnetic field in a frequency band ranging from 110 to 205 kHz.

33. A kit comprising an outer element which is a sheath according to any one of claims 9 to 32, and an inner element which is a shaft or catheter having a coil circuit, wherein the outer element covers at least one segment of the inner element.

34. The kit according to claim 33, wherein the inner element is configured to be coaxial with respect to the outer element.

35. The kit according to claim 33 or 34, wherein the inner coil is configured to transmit energy to the outer element.

36. The kit according to claim 35, wherein the inner coil is configured to receive data from the outer element by wireless transmission.

37. The kit according to any one of claims 33 to 36, wherein the outer coil is configured to receive data from the inner element by wireless transmission.

38. The kit according to any one of claims 33 to 37, wherein the internal element is the shaft of a percutaneous cardiac pump.

39. A method for calculating the cardiac output (CO) of a living organism, wherein a mathematical model is constructed that links an input data vector with a target CO value.

40. The method according to claim 39, wherein the mathematical model is nonlinear.

41. The method according to claim 39 or 40, wherein the input data vector comprises at least one sensor measurement value obtained by a medical invasive device according to any one of claims 1 to 32.

42. The method according to any one of claims 39 to 41, wherein the input data vector includes physiological input source data from the living organism.

43. The method according to any one of claims 39 to 42, wherein the input data vector includes the area below the curve of repeated temperature measurements.

44. The method according to any one of claims 39 to 43, wherein the input data vector includes the area below the curve of repeated temperature measurements after a bolus of fluid has been injected into the venous circulation, and the injected bolus has a temperature different from the blood temperature.

45. The method according to any one of claims 39 to 44, wherein the input data vector includes numerical values ​​obtained from arterial pulse pressure analysis.

46. The method according to any one of claims 39 to 45, wherein the input data vector includes a numerical value obtained from arterial pulse pressure analysis, and the numerical value is one of the following: heart rate interval, heart rate, systolic blood pressure, diastolic blood pressure, pulse pressure, peak systolic pressure difference for each time difference, area below the pulse curve, and area below the systolic portion of the pulse pressure wave.

47. The method according to any one of claims 39 to 46, wherein the input data vector includes at least one of the systolic pressure of the living organism, the diastolic pressure of the living organism, and the pulse pressure of the living organism.

48. The method according to any one of claims 39 to 47, wherein the input data vector includes at least one of the following: the age of the organism, the sex of the organism, the height of the organism, the weight of the organism, and the temperature of the organism.

49. The method according to any one of claims 39 to 48, wherein the input data vector includes at least one of the following: type of heart pump, performance setting of heart pump, size of heart pump, blood flow rate of heart pump, rotational speed of heart pump, power consumption of heart pump, current consumption of heart pump, and reading of heart pump pressure sensor.

50. The method according to any one of claims 39 to 49, wherein the target CO value is determined by an algorithm that includes the step of determining the area under a curve of temperatures measured repeatedly at multiple time points.

51. The method according to any one of claims 39 to 50, wherein the target CO value is determined by analysis of physiological signals measured by a medical invasive device according to any one of claims 1 to 32.

52. The method according to any one of claims 39 to 51, wherein the step of generating the mathematical model includes the step of fitting the input data vector to the target CO value in the least-squares optimal manner.

53. The method according to any one of claims 39 to 52, wherein the step of generating the mathematical model includes training an artificial neural network (ANN).

54. The method according to any one of claims 39 to 53, wherein the step of generating the mathematical model includes unsupervised learning of a deep neural network (DNN).

55. The method according to any one of claims 39 to 53, wherein the step of generating the mathematical model includes supervised learning of a deep neural network (DNN).

56. The method according to any one of claims 39 to 55, wherein the step of generating the mathematical model includes training a deep believe network (DBN).

57. A method for calculating the cardiac output (CO) of a living organism by the mathematical model according to any one of claims 39 to 56, comprising the steps of: obtaining an input data vector; transforming the input data vector using at least the mathematical model; and expressing the result of the transformation as a CO value in physiological units.

58. A method for calculating the cardiac output (CO) of a living organism according to any one of claims 39 to 57, comprising the steps of: obtaining a plurality of target CO values; generating a mathematical model based on at least a portion of the target CO values; obtaining an input data vector; transforming the input data vector using at least the mathematical model; and expressing the result of the transformation as a CO value in physiological units.

59. An apparatus comprising a device for receiving data transmitted by a medical invasive device according to any one of claims 1 to 32.

60. The apparatus according to claim 59, wherein data is transmitted wirelessly by the medical invasive device.

61. The apparatus according to claim 59 or 60, further comprising a device for receiving data transmitted from a second device and used for deriving an input data vector.

62. The apparatus according to claim 61, wherein the second apparatus is defined as a medical monitor configured to be placed in the same room as the patient, and comprises a display configured to display the patient's vital signs.

63. The apparatus according to claim 61 or 62, wherein the second apparatus is a control device for a heart pump.

64. The apparatus according to any one of claims 61 to 63, further comprising a device for receiving data transmitted wirelessly from the second device and used for deriving the input data vector.

65. The apparatus according to any one of claims 60 to 64, wherein wireless data transmission conforms to one of the Wi-Fi standard, Bluetooth standard, or Ant standard.

66. A computer program comprising a code structure configured to perform the method described in any one of claims 39 to 58 when executed on a computer.

67. The apparatus according to any one of claims 59 to 65, comprising the computer program according to claim 66.

68. The apparatus according to any one of claims 59 to 65 and 67, comprising a display configured to show at least CO.

69. A computer program according to claim 66, stored on a computer-readable medium.

70. A computer program product stored on a machine-readable carrier, comprising program code means for implementing the method described in any one of claims 39 to 58 when executed on a computer.

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