Abstract: A distributed medical sensing system including a first hub configured to receive first medical characteristic data from a first body sensing device, the first body sensing device being located in a first sterile field and a second hub configured to receive second medical characteristic data from a second body sensing device, the second body sensing device being located in a second sterile field spaced from the first sterile field. The system also includes a computing device outside of the first and second sterile fields and communicatively coupled to the first and second hubs, the computing device configured to receive the first and second medical characteristic data from the respective first and second hubs, process the first and second medical characteristic data, and transmit the processed first and second medical characteristic data to the respective first and second hubs.

Abstract: An electronic catheter stethoscope measures and analyzes acoustic fields and dynamic pressure variations in the gaseous or liquid fluid inside a conventional medical catheter that is positioned in a patient's urologic, digestive, reproductive, cardiovascular, neurological or pulmonary system. Measurement transducers are installed in a housing connectable to multiple preselected medical catheters. The transducers detect bodily functions that are transmitted to the preselected catheter from within the body. The transducers, housing, electrical interface and signal processing electronics are positioned outside the body.

Abstract: Catheter based system for providing functional and morphological characterization of arteries, comprising a catheter (1) configured for insertion in an artery (3), and a sensor system (5) for mapping hemodynamic parameters mounted on the catheter (1), the sensor system comprising at least two anemometric probes (7, 8a, 8b, 9a, 9b, 19, 20, 21, 22) spatially arranged in a deployed position and configured to measure flow velocity components (Vx, Vr) in at least two different positions spaced apart in a radial direction R of such that a possible restriction of the artery due for example to a stenosis, plaque, or other local deformation (3a) of the artery is measurable.

Abstract: Provided herein are implantable systems that include an implantable photoplethysmography (PPG) sensor, which can be used to obtain an arterial PPG waveform. In an embodiment, a metric of a terminal portion of an arterial PPG waveform is determined, and a metric of an initial portion of the arterial PPG waveform is determined, and a surrogate of mean arterial pressure is determined based on the metric of the terminal portion and the metric of the initial portion. In another embodiment, a surrogate of diastolic pressure is determined based on a metric of a terminal portion of an arterial PPG waveform. In a further embodiment, a surrogate of cardiac afterload is determined based on a metric of a terminal portion of an arterial PPG waveform.

Abstract: Several different smart stent structures are described for placement in vessel of a mammal. The stents can be advantageously used to perform measurements of the conditions in the vessel and transmit the measurements wireless out from the patient. In some embodiments, the stent performs therapy within the vessel and may be controlled with a microprocessor, which may or may not communicate wirelessly. Some implantable devices comprise a drug delivery system based, for example, on either a microelectromechanical structure or a cover that opens upon application of an electrical current. Smart devices can be used, for example, the detect deposits in a vessel, aneurysms in the vessel or other modifications of flow in the vessel.

Abstract: A method includes monitoring an indicator of fluid volume of a patient via a sensor device, and setting an initial fluid volume removal prescription for a blood fluid removal session based on the monitored indicator of fluid volume. The method may further include transmitting data regarding the indicator of fluid volume from the implantable sensor device to fluid removal device. In some embodiments, the fluid removal device sets or calculated the initial fluid volume removal prescription based on the data received from the implantable sensor. The indicator of fluid volume may be an indicator of tissue fluid volume or an indicator of blood fluid volume.

Abstract: The present invention relates to a sensor guide wire (17) for intravascular measurements of physiological variables in a living body, having a proximal region (8), a distal sensor region (9) and a tip region (10). The sensor guide wire (17) further comprises a core wire member (11), a sensor element (14), which has a sensor portion (15), for measuring the physiological variable and to generate a sensor signal in response to said variable and a jacket (13), accommodating at least a part of said sensor element (14). The sensor portion (15), is sensitive to one or many of the physiological variables, pressure, temperature, and flow The core wire member (11) comprises two separate parts, a first core wire part (19) and a second core wire part (20), wherein a distal end (21) of said first core wire part (19) is attached to said jacket (13) proximally said sensor portion (15) and a proximal end (22) of said second core wire part (20) is attached to said jacket (13) distally to said sensor portion (15).

Abstract: Exemplary techniques and systems for interpolating left ventricular pressures are described. One technique interpolates pressures within the left ventricle from blood pressures gathered without directly sensing blood pressure in the left ventricle.

Abstract: An electrical connector is described. In one implementation, the connector includes a female portion including one or more electrical contacts and a male portion including one or more electrical contacts. The female portion and the male portion each have a self-orientating geometry that allows the male portion to be mated with the female portion in any rotational position along 360 degrees of rotation. When mated, the electrical contacts of the female portion mate with corresponding one or more electrical contacts of the male portion to form one or more electrical connections between two electronic components.

Abstract: A catheter includes a flexible shaft having a length sufficient to access a patient's renal artery relative to a percutaneous access location. A treatment arrangement is provided at a distal end of the shaft and configured for deployment in the renal artery. The treatment arrangement includes an ablation arrangement configured to deliver renal denervation therapy. An occlusion arrangement is configured for deployment in the renal artery and for altering blood flow through the renal artery during or subsequent to renal denervation therapy delivery. A monitoring unit is configured for monitoring for a change in one or more physiologic parameters influenced by the renal denervation therapy. The monitoring unit is configured to produce data useful in assessing effectiveness of the renal denervation therapy based on the physiologic parameter monitoring.

Abstract: The invention relates to a device for determining cardiopulmonary volumes and flows of a living being. According to the invention, the evaluation unit (14) of a transpulmonary measurement arrangement, preferably having a central-vein catheter and an arterial catheter (11, 12), is set up, in terms of program technology, for the purpose of taking a possible short-circuit current from the right to the left half of the heart (RL shunt) and/or from the left to the right half of the heart (LR shunt) of the living being into consideration, without the use of a right-heart catheter being required in this connection, or any recourse to pulmonary artery measurement values having to take place at all. In this connection, a model is used as the basis, which contains the function y (system response) corresponding to a dilution curve as the convolution of a disruption function I with several terms that contain characteristic times as model parameters.

Abstract: Methods and devices are disclosed that, in various embodiments and permutations and combinations of inventions, diagnose and treat Pulmonary Embolism or associated symptoms. In one series of embodiments, the invention consists of methods and devices for identifying patients whose Pulmonary Embolism or associated symptoms are caused or exacerbated, at least in part, by blockages of one or more of the patient's internal pulmonary veins. In some instances, stenoses or other flow limiting structures or lesions in the patient's affected veins are identified. Further, in some instances the nature of such lesions and whether there is a significant disruption of blood pressure, or both, is ascertained. In some embodiments, methods and devices for applying one or more therapies to the blockages in the patient's pulmonary veins are provided.

Abstract: A micromachined sensor for measuring vascular parameters, such as fluid shear stress, includes a substrate having a front-side surface, and a backside surface opposite the front-side surface. The sensor includes a diaphragm overlying a cavity etched within the substrate, and a heat sensing element disposed on the front-side surface of the substrate and on top of the cavity and the diaphragm. The heat sensing element is electrically couplable to electrode leads formed on the backside surface of the substrate. The sensor includes an electronic system connected to the backside surface and configured to measure a change in heat convection from the sensing element to surrounding fluid when the sensing element is heated by applying an electric current thereto, and further configured to derive from the change in heat convection vascular parameters such as the shear stress of fluid flowing past the sensing element.

Abstract: Systems, devices and methods of monitoring blood flow velocity are disclosed herein. For example, one method of monitoring blood flow velocity includes: locating a blood flow velocity sensor near the ostium in the coronary sinus; and sensing towards a portion of the aorta. A second example method includes: locating a blood flow velocity sensor in a vein; and sensing towards an adjacent artery. A third example method includes: locating a blood flow velocity sensor near the tricuspid valve; and sensing towards a tricuspid valve annulus. A fourth example method includes: locating a blood flow velocity sensor right ventricular outflow tract; and sensing towards a portion of the aorta. A fifth example method includes: locating a blood flow velocity sensor in the great cardiac vein; and sensing towards a left anterior descending artery. A sixth example method includes: locating a blood flow velocity sensor in the right atrial appendage; and sensing towards a portion of the aorta.

Abstract: The present invention provides for an improved combination sensor tip that includes a pressure sensor and a second sensor other than a pressure sensor, both disposed at or in close proximity to the distal end of the combination sensor tip. The present invention also provides for an improved connector to couple a guide wire to a physiology monitor that reduces torsional resistance when maneuvering the guide wire.

Abstract: A catheter for retrograde orientation in a blood flow is used to determine the blood flow rate by thermodilution measurements. The determination of the blood flow rate accommodates injectate induced thermal influences on a dilution thermal sensor, wherein the thermal influences can occur prior to introduction of the injectate into the blood flow.

Abstract: An improved system for measuring changes in blood flow, particularly in the context of an automatic arrhythmia treatment device. The system includes a heater, exposable to a bloodstream, a driver providing power to the heater, a temperature sensor, isolated from the blood stream and thermally coupled to the temperature of the heater and a measurement circuit coupled to the temperature sensor, providing signals indicative of blood flow. The system may include an intravascular lead having a lead body wherein the heater is mounted to the lead body so as to dissipate its generated heat into the blood. The heater and temperature sensor may be thermally insulated from the lead body and the heater and the temperature sensor may be on substantially a single isotherm during operation.

Abstract: Embodiments of the present invention provide blood flow sensors that can be used for measurement of various physiological parameters under a wide array of conditions. In some embodiments, the blood flow sensor can be implanted into a blood vessel and left in place indefinitely and will unobtrusively measure and record data as the patient engages in regular daily activities. The data can later be read out by a clinician using a suitable interface. In other embodiments, the data is collected and analyzed within a data collection device implanted in or attached to the patient's body, and the collection device can report to the patient on an ongoing basis or in the form of alerts issued when conditions requiring medical intervention are detected.

Abstract: The systems and methods described herein allow measurement of the velocity of a pulse wave propagating within a body lumen using an intravascular elongate medical device. The elongate medical device can include a data collection device configured to collect pulse wave data at a location within the lumen. The data collection device is communicatively coupled with a velocity measurement system and configured to output the collected data to the velocity measurement system. The velocity measurement system is configured to calculate the velocity of the pulse wave based on the collection data. The velocity of a pulse wave over a region of the lumen can be used for tissue characterization, diagnosis and the like.

Abstract: A catheter for retrograde orientation in a blood flow is used to determine the blood flow rate by thermodilution measurements. The determination of the blood flow rate accommodates injectate induced thermal influences on a dilution thermal sensor, wherein the thermal influences can occur prior to introduction of the injectate into the blood flow.

Abstract: A method for determining an arteriovascular condition of a subject having an arterial blood flow is shown. The method involves determining a temporal progression of an instantaneous blood flow condition of the arterial blood flow as well as deriving a slew rate of the temporal progression during an increase of the temporal progression. In addition, an arteriovascular condition indicator device is shown, which comprises: an input for receiving an input signal representing an instantaneous arterial blood flow condition of a subject and a slew rate monitor connected to the input. A corresponding control device for providing an activation signal is also shown. The control device comprises a maximum detector connected to the slew rate monitor. A method for stimulation of arteriogenesis is also shown, wherein a temporal progression of an instantaneous blood flow condition is monitored, a slew rate of the temporal progression is derived, and the maximum of the slew rate is determined.

Abstract: The present invention provides a multipurpose host system for processing and displaying invasive cardiovascular diagnostic measurement data. The system includes a an external input signal bus interface. The bus interface receives data arising from cardiovascular diagnostic measurement sensors. Measurement processing components receive data from particular sensor types. Based on the received data, the processing components render diagnostic measurement parameter values. A multi-mode graphical user interface includes display components corresponding to data received from particular sensor types. The user interface provides recommended action prompts that guide a user through a series of actions.

Abstract: Devices, systems, and methods for determining fractional flow reserve. At least one method for determining fractional flow reserve of the present disclosure comprises the steps positioning a device comprising at least two sensors within a luminal organ at or near a stenosis, wherein the at least two sensors are separated a predetermined distance from one another, operating the device to determine flow velocity of a second fluid introduced into me luminal organ to temporarily displace a first fluid present within the luminal organ, and determining fractional flow reserve at or near the stenosis based upon the flow velocity, a mean aortic pressure within the luminal organ, and at least one cross-sectional area at or near the stenosis. Devices and systems useful for performing such exemplary methods are also disclosed herein.

Abstract: A method of measuring blood pressure and velocity proximally and distally of a stenosis in a vessel carrying blood includes the steps of providing a guide wire having both a pressure sensor and a velocity sensor disposed on a distal region of the guide wire, introducing the guide wire into the vessel, advancing the guide wire to position the pressure sensor and the velocity sensor proximally and distally of the stenosis, and measuring the blood pressure and velocity proximally and distally of the stenosis with the pressure sensor and the velocity sensor.

Abstract: A device for measuring the blood flow of a body tissue comprises a catheter having a catheter head for the insertion into the inside of a body tissue and a center piece having a light emission surface, out of which an optical conductor leads, and having a reflection surface, which is disposed opposite of the light emission surface and oriented obliquely to the longitudinal axis of the optical conductor. The optical conductor is disposed such that an emitted light beam is directed at the reflection surface, the emitted light beam can be deflected at the reflection surface and reflected into the body tissue, and a reflected light beam can be reflected out of the body tissue at the reflection surface and fed into the optical conductor. The catheter head is divided into an insertion region and a connecting region, wherein the insertion region comprises a plurality of recesses on the surface thereof. In the direction of the connecting region, the insertion region has an increasing diameter.

Abstract: The inventive implantable Doppler tomography system allows, for the first time, the use of Doppler shift for purposes of tracking cardiac wall motion. The present inventive Doppler tomography system methods and devices provide a critical new tool in the physician's armamentarium which provides accurate, real time monitoring of the mechanical performance of the heart.

Abstract: Disclosed herein is an electromagnetic flow sensor device for monitoring flow of fluid in a channel. The sensor device includes a first electrode to be disposed along the channel and in communication with the fluid, a second electrode to be disposed along the channel and in communication with the fluid, and a radially expandable frame to structurally support the first electrode and the second electrode while conforming to the channel to position the first electrode and the second electrode along the channel. The device may also include an antenna coupled to the first and second electrodes to wirelessly provide an indication of a voltage induced between the first and second electrodes. In some embodiments, the radially expandable frame includes an insulating link such that the first and second electrodes are not electrically connected via the radially expandable frame.

Abstract: A stent for placement in a blood vessel of a patient, the stent including: a proximal end, a distal end, and a generally circular cross-section with a diameter; a Micro Electro-Mechanical System (MEMS) ultrasound sensor using a Doppler principle for determining patency and flow rate through the cross-section, and pressure drop from the proximal end to the distal end; a transmitter for providing signals to an external receiver outside the patient's body; and a coil device for receiving energy from outside the patient's body and coupled to the transmitter for powering the transmitter.

Abstract: This invention concerns miniature implantable power sources that harvest or scavenge energy from the expansion and contraction of biological tissues, for example, an artery or a bundle of muscle fiber. Such power sources employ an energy harvesting element that converts mechanical or thermal energy existing or generated in or from a pulsatile tissue into a form of electrical energy that can be used or stored by an implanted medical device, such as a blood pressure sensor, a flow meter, or the like. Preferred energy harvesting element embodiments utilize a piezoelectric thin film embedded within a flexible, self-curling medical-grade polymer or coating. Such power sources can be used to produce self-powered implanted microsystems with continuous or near-continuous operation, increased lifetimes, reduced need for surgical replacement, and minimized or eliminated external interface requirements.

Abstract: An injectable wireless perfusion sensor provides data to an external device regarding the perfusion of the targeted tissue. The sensor permits a caregiver to monitor cardiovascular performance in specific areas such as the extremities. The sensor will identify whether vascular constriction or obstruction is present and to what extent. Further, once such a condition is treated, the sensor will monitor the effectiveness of that treatment.

Abstract: The present invention provides a new mechanical sensor approach to maneuvering catheters and other cardiac devices into blood outlets, with particular application to maneuvering cardiac devices into the coronary sinus and beyond. Additionally, the inventive sensing device provides assessment of the viability of branching veins and other potential device sites, such as within the coronary venous system.

Abstract: A technique is disclosed for determining blood flow in a living body by changing the thermal energy level in the venous blood flow path and determining temperatures in both the venous and arterial blood flow paths. Blood flow is calculated as a function of the change in energy level and the temperature differences in the venous and arterial blood flow paths.

Abstract: Systems and methods described herein include an array of sensors positioned on a tool. In one embodiment, among others, a tool includes a handle configured to be manipulated by a user. The tool also includes an end portion arranged in mechanical communication with the handle. In addition, the tool includes an array of sensors mounted on the end portion, in which the array of sensors is configured to sense a property of an object. The tool also comprises a processing device configured to process the properties of the object sensed by the array of sensors and to obtain spatial information of the object. The processing device is further configured to communicate the spatial information to the handle.

Abstract: A measurement system for examining a section of tissue on a patient in which electric current and/or voltages are applied to a patient in at least one location and are measured on the section of tissue to be examined by at least one electrode of a contact surface of the measurement system. As a result, conclusions can be drawn about the interior of the section of tissue to be examined. The electrode is at least partially surrounded by a conductor element for contacting with a potential which deviates from that of the conductor element.

Abstract: A measurement method for determining the blood flow rate QF in blood carrying lines is provided. It may be used in particular to determine the blood flow in a patient's vessel, which is connected to the extracorporeal circulation of a blood treatment machine by an arterial line and a venous line. According to the method, the net rate dX/dt of a variable X is determined, with X being derived from a physicochemical variable Y of the blood with the help of values YA and YV which are adequately constant over time and which respectively characterize the physicochemical property in the arterial line and the venous line during the measurement interval. The net rate dX/dt is then used to determine the blood flow rate QF. The targeted use of indicators is not necessary.

Abstract: Methods, systems and devices are provided for monitoring respiratory disorders based on monitored factors of a photoplethysmography (PPG) signal that is representative of peripheral blood volume. The monitored factors can be respiratory effort as well as respiratory rate and/or blood oxygen saturation level. The systems and devices may or may not be implanted in a patient.

Abstract: A system for delivery of a capsule to a target location within a subject body including a capsule including a locomotion element and a gamma emitting radioactive source, a radiation tracking subsystem capable of locating the gamma emitting radioactive source in three dimensions, and a locomotion control subsystem capable of controlling movement of the capsule by effecting movement of the locomotion element, based, at least partly, on a location of the gamma emitting radioactive source provided by the radiation tracking subsystem.

Abstract: The systems and methods described herein allow measurement of the velocity of a pulse wave propagating within a body lumen using an intravascular elongate medical device. The elongate medical device can include a data collection device configured to collect pulse wave data at a location within the lumen. The data collection device is communicatively coupled with a velocity measurement system and configured to output the collected data to the velocity measurement system. The velocity measurement system is configured to calculate the velocity of the pulse wave based on the collected data. The velocity of a pulse wave over a region of the lumen can be used for tissue characterization, diagnosis and the like.

Abstract: A device for the in vivo determination of the blood flow rate in a patient's blood vessel includes a microelectrode arrangement provided for placement in the blood vessel, an electrical power source which provides excitation energy having physiologically harmless parameters for obtaining a measured signal, a signal detector for detecting an electrical measured signal resulting from the blood flow in the presence of the excitation energy at measuring electrodes of the microelectrode arrangement, and a signal evaluation device, connected to the signal detector, for determining the blood flow rate on the basis of the measured signal.

Abstract: Enables a measurement catheter configured to hold a package such as an optical tomographic module and/or blood flow velocity module. May hold any package reduced to a size small enough to fit in a blood vessel. Example packages include an optical transmitter and receiver/detectors that enable internal optical tomographic images of vessels to be captured, for example without rotation of the catheter in the vessel. Alternatively or in combination, a thermal package may be coupled to the measurement catheter that includes a thermal element and detector(s) that enable blood flow velocity to be accurately internally measured that does not require a static catheter position. In addition, the measurement catheter may optionally attach to an interchangeable coupler that allows for the introduction of substitution of packages or any type of catheter end assembly to provide rapid deployment of additional surgical or sensory elements.

Abstract: A method for occluding a body lumen includes providing a clamping device having a pair of opposed pressure applying jaws, providing a sensor on one of the pressure applying jaws for sensing blood flow through a body lumen, and releasably securing a luminal clip between the pressure applying jaws. The method includes using the sensor for detecting blood flow through the body lumen for locating the body lumen, positioning the luminal clip adjacent the located body lumen, and closing the pressure applying jaws for clamping the luminal clip over the body lumen for at least partially occluding blood flow through the body lumen.

Abstract: A system for conducting flow measurements in grafts is provided, comprising a graft that further includes a monitor placed within or on the graft, wherein the monitor measures flow. In exemplary embodiments, the monitor is an embedded monitor that is placed within or on a vascular bypass graft that is commonly used for arterial and venous bypass or for hemo-dialysis access, ultrafiltration, or phoresis. The exemplary monitoring system may measure flow by electrical impedance, electronic and/or magnetic flux. An external monitor may also be intermittently applied. Alternately, a continuous reporting can be performed by telepathic signals from the graft transmitter.

Abstract: Methods are provided for partial aortic occlusion for cerebral perfusion augmentation in patients suffering from global or focal cerebral ischemia. The descending aorta is accessed. A device is then located downstream from the takeoff of the brachiocephalic artery. The device is operated to at least partially obstruct blood flow in the aorta during systole and diastole. A physiologic parameter can be measured. The device can then be adjusted to modify the degree of obstruction based on the measured physiologic parameter.

Abstract: A method of measuring blood flow including several steps. In an initial step a first ultrasound beam is oriented in a direction substantially perpendicular to the direction of the blood flow to be measured. Next, the Doppler spectrum obtained from the backscattered echoes of said first ultrasound beam is measured. Subsequently, the ultrasound beam is reoriented so that the Doppler spectrum of the backscattered echoes of the ultrasound beam is substantially symmetrical around the zero frequency. The Doppler frequency of the backscattered echoes of a second ultrasound beam oriented at a fixed angle to the first ultrasound beam is then measured. Finally, the rate of blood flow is calculated based on the angle between the ultrasound beams and the measured Doppler frequency of the backscattered echoes of the second ultrasound beam.

Abstract: A device and a method for measuring viscosity that includes attaching molecular rotors to a solid surface, exposing the solid surface to a fluid having a viscosity to be measured, and taking optical measurements to determine viscosity. The solid surface is preferably quartz, polystyrene or silicate glass, such as a fiber optic probe or a glass cuvette. The molecular rotors are of the type that includes an electron-donor group and electron-acceptor group that are linked by a single bond so that the groups may rotate with respect to one another, and that exhibit a fluorescence emission when rotation is hindered.

Abstract: The invention relates to a method for obtaining an indication of cardiac output, comprising the steps of introducing into the bloodstream a liquid with a temperature lower than the temperature of the blood, measuring downstream the temperature variation of the blood, and performing a thermodilution algorithm on the basis of the measured temperature variation of the blood. The invention is distinguished in that the temperature variation is measured upstream of the heart in the blood flow of a vein in which the flow rate is substantially proportional to the cardiac output, and the flow rate in the vein is determined using the thermodilution algorithm. The invention also relates to an assembly, catheter and processing device for obtaining an indication of cardiac output.

Abstract: A technique is disclosed for determining blood flow in a living body by changing the thermal energy level in the venous blood flow path and determining temperatures in both the venous and arterial blood flow paths. Blood flow is calculated as a function of the change in energy level and the temperature differences in the venous and arterial blood flow paths.

Abstract: An improved method and apparatus for measuring changes in blood flow, particularly in the context of an automatic arrhythmia treatment device. The invention may employ a flow sensor which is activated in response to detection of a tachyarrhythmia or in response to delivery of an anti-tachyarrhythmia therapy. If activated in response to detection of tachyarrhythmia, the flow sensor may be employed to determine whether a substantial drop in cardiac output has or has not occurred, in order to select an appropriate therapy, in particular to avoid unnecessary delivery of high level shocks. If activated in response to delivery of an anti-tachyarrhythmia therapy, the flow sensor may be employed to determine whether the therapy was or was not successful in correcting a low cardiac output or whether a reduced cardiac output followed delivery of the therapy.

Abstract: A catheter for retrograde orientation in a blood flow is used to determine the blood flow rate by thermodilution measurements. The determination of the blood flow rate accommodates injectate induced thermal influences on a dilution thermal sensor, wherein the thermal influences can occur prior to introduction of the injectate into the blood flow.

Abstract: An electrical connector is described. In one implementation, the connector includes a female portion including one or more electrical contacts and a male portion including one or more electrical contacts. The female portion and the male portion each have a self-orientating geometry that allows the male portion to be mated with the female portion in any rotational position along 360 degrees of rotation. When mated, the electrical contacts of the female portion mate with corresponding one or more electrical contacts of the male portion to form one or more electrical connections between two electronic components.