Abstract: Various aspects of the present subject matter relate to a device. In various embodiments, the device comprises at least one port adapted to connect at least one lead, a CRM functions module connected to the port and adapted to provide at least one CRM function using the lead, a neural function module, and a controller connected to the CRM functions module and the neural function module. The at least one CRM function includes a function to provide an electrical signal to the lead to capture cardiac tissue. The neural function module includes a signal processing module connected to the port and adapted to receive and process a nerve traffic signal from the lead into a signal indicative of the nerve traffic. The controller is adapted to implement a CRM therapy based on the signal indicative of the nerve traffic. Other aspects are provided herein.

Abstract: Methods and kits are provided for determining an increased likelihood of the occurrence of a cardiac arrhythmia, myocardial ischemia, congestive heart failure and other diseased conditions of the heart. The methods and kits comprise measuring serum NGF levels in a subject and detecting increases in NGF levels over baseline. The methods may further comprise initiating preventive therapy in response to a detected increase in serum NGF levels.

Abstract: In an embodiment, the invention includes an implantable medical device with a pulse generator and a chemical sensor in communication with the pulse generator, the chemical sensor configured to detect an ion concentration in a bodily fluid. In an embodiment, the invention includes a method for providing cardiac arrhythmia therapy to a patient including sensing a physiological concentration of an analyte, communicating data regarding the physiological concentration of the analyte to an implanted pulse generator, and delivering therapy to the patient based in part on the physiological concentration of the ion. In an embodiment, the invention includes a method for monitoring diuretic therapy. In an embodiment, the invention includes a method for controlling delivery of an active agent into a human body. Other aspects and embodiments are provided herein.

Abstract: The present invention provides a method of affecting physiological disorders by stimulating a specific location along the sympathetic nerve chain. Preferably, the present invention provides a method of affecting a variety of physiological disorders or pathological conditions by placing an electrode adjacent to or in communication with at least one ganglion along the sympathetic nerve chain and stimulating the at least one ganglion until the physiological disorder or pathological condition has been affected.

Abstract: Embodiments of the invention are related to monitoring devices and methods with osmometric sensors, amongst other things. In an embodiment, the invention includes an implantable heart failure monitoring system including an implantable osmometric sensor configured to generate a signal corresponding to osmotic strength of a bodily fluid, the osmometric sensor comprising a rigid wall member defining an enclosed volume resisting deformation, the rigid wall member comprising a semi-permeable membrane; a signaling element comprising a first pressure sensor; and a second pressure sensor. Other aspects and embodiments are provided herein.

Abstract: In some examples, an electromechanical disassociation state (EMD) of a heart of a patient can be treated by delivering electrical stimulation to a tissue site to at least one of modulate afferent nerve activity or inhibit efferent nerve activity upon determining that the heart is in an electromechanical dissociation state, where the tissue site comprises at least one of a nonmyocardial tissue site or a nonvascular cardiac tissue site. The delivery of electrical stimulation may effectively treat the EMD state of the heart, e.g., by enabling effective mechanical contraction of the heart. In another example, an electromechanical disassociation state of a heart of a patient can be treated by determining autonomic nervous system activity associated with a detected EMD state of the heart of a patient, and delivering electrical stimulation therapy to the patient based on the determined autonomic nervous system activity of the patient associated with the EMD state.

Abstract: Various aspects of the present subject matter relate to a device. In various embodiments, the device comprises at least one port adapted to connect at least one lead, a CRM functions module connected to the port and adapted to provide at least one CRM function using the lead, a neural function module, and a controller connected to the CRM functions module and the neural function module. The at least one CRM function includes a function to provide an electrical signal to the lead to capture cardiac tissue. The neural function module includes a signal processing module connected to the port and adapted to receive and process a nerve traffic signal from the lead into a signal indicative of the nerve traffic. The controller is adapted to implement a CRM therapy based on the signal indicative of the nerve traffic. Other aspects are provided herein.

Abstract: A technique utilizing an endolymphatically implanted lead having one or more electrodes that may be used for sensing cardiac activity and/or delivering cardiac electrical stimulation by an implantable cardiac device. An electrode disposed in the thoracic duct is in close proximity to the left ventricle and generates an electrogram especially suitable for ischemia detection and/or discriminating between ventricular tachycardias and supraventricular tachycardias.

Abstract: Methods for monitoring a patient's level of B-type natriuretic peptide (BNP), and implantable cardiac systems capable of performing such methods, are provided. A ventricle is paced for a period of time to provoke a ventricular evoked response, and a ventricular intracardiac electrogram (IEGM) indicative of the ventricular evoked response is obtained. Based on the ventricular IEGM, there is a determination of at least one ventricular evoked response metric (e.g., ventricular evoked response peak-to-peak amplitude, ventricular evoked response area and/or ventricular evoked response maximum slope), and the patient's level of BNP is monitored based on determined ventricular evoked response metric(s). Based on the monitored level's of BNP, the patients heart failure (HF) condition and/or risks and/or occurrences of certain events (e.g., an acute HF exacerbation and/or an acute myocardial infarction) can be monitored.

Abstract: An apparatus for monitoring a patient's blood glucose level. The apparatus includes an implantable medical device having a controller and an implantable heart sounds sensor configured to transmit signals to the controller of the implantable medical device. The controller is configured to determine if a patient is hypoglycemic or hyperglycemic based on the signals from the heart sounds sensor. A method is also disclosed that includes sensing the patient's heart sounds, determining the amplitude of the S2 heart sound, determining the length of the interval from the S1 heart sound to the S2max heart sound, determining the length of the interval from the S1 heart sound to the S2end heart sound, and determining the patient's blood glucose status based on the patient's heart sounds.

Abstract: Embodiments of the invention are related to monitoring devices and methods with osmometric sensors, amongst other things. In an embodiment, the invention includes an implantable heart failure monitoring system including an osmometric sensor, the osmometric sensor configured to generate a signal corresponding to the osmotic strength of a bodily fluid, and a controller in communication with the osmometric sensor, the controller configured to receive and process the signal corresponding to the osmotic strength of a bodily fluid. Other aspects and embodiments are provided herein.

Abstract: Energy efficient methods and systems for using multi-dimensional activity sensors with implantable cardiac devices are provided. In certain embodiments the output of a passive activity sensor (used for rate responsive pacing) is used to trigger temporary use of a relatively high power multi-dimensional activity sensor. In other embodiments, the output of a relatively low power oxygen saturation sensor is used to trigger temporary use of a relatively high power multi-dimensional activity sensor. This description is not intended to be a complete description of, or limit the scope of, the invention.

Abstract: A glycemic condition is indicated based on variance of a feature derived from cardiac electrogram data. Neurostimulation is then used to counteract a cardiac-related autonomic response to the glycemic condition. For example, stimulation of parasympathetic innervation may be used to counteract an autonomic sympathetic response that is associated with hypoglycemia or hyperglycemia. In addition, stimulation of sympathetic innervation may be used to counteract an autonomic parasympathetic response that is associated with hypoglycemia or hyperglycemia.

Abstract: A device and method for delivering electrical stimulation to the heart in order to improve cardiac function in heart failure patients. The stimulation is delivered as high-output pacing in which the stimulation is excitatory and also of sufficient energy to augment myocardial contractility. The device may be configured to deliver high-output pacing upon detection of cardiac decompensation.

Abstract: An implantable biosensor system is disclosed for determining levels of cardiac markers in a patient to aid in the diagnosis, determination of the severity and management of cardiovascular diseases. The sensor includes nanowire sensor elements having a biological recognition element attached to a nanowire transducer that specifically binds to the cardiac marker being measured. Each of the sensor elements is associated with a protective member that prevents the sensor element from interacting with the surrounding environment. At a selected time, the protective member may be disabled, thereby allowing the sensor element to begin sensing signals within a living body.

Abstract: A device and method for improving the stability of a ventilation pattern of a patient (1) uses a sensor (4) for sensing a parameter which reflects a level of lung gas in a patient, such as oxygen or carbon dioxide. The output signal of the sensor is received by a processor (3) which assesses the level of lung gas of the patient and activates means (18,20) for increasing the lung gas level of the patient beyond what it would otherwise have been without treatment in response to a decreasing level or a predicted decreasing level of the lung gas. Thus the device can be used to retard a decrease in said lung gas level, thereby reducing oscillations in the respiration.

Abstract: An implantable substrate sensor has electronic circuitry and electrodes formed on opposite sides of a substrate. A protective coating covers the substrate, effectively hermetically sealing the electronic circuitry under the coating. Exposed areas of the electrodes are selectively left uncovered by the protective coating, thereby allowing such electrodes to be exposed to body tissue and fluids when the sensor is implanted in living tissue. The substrate on which the electronic circuitry and electrodes are formed is the same substrate or “chip” on which an integrated circuit (IC) is formed, which integrated circuit contains the desired electronic circuitry. Such approach eliminates the need for an hermetically sealed lid or cover to cover hybrid electronic circuitry, and allows the sensor to be made much thinner than would otherwise be possible. In one embodiment, two such substrate sensor may be placed back-to-back, with the electrodes facing outward.

Abstract: Embodiments of the invention are related to monitoring devices and methods with osmometric sensors, amongst other things. In an embodiment, the invention includes an implantable heart failure monitoring system including an osmometric sensor, the osmometric sensor configured to generate a signal corresponding to the osmotic strength of a bodily fluid, and a controller in communication with the osmometric sensor, the controller configured to receive and process the signal corresponding to the osmotic strength of a bodily fluid. Other aspects and embodiments are provided herein.

Abstract: A cardiac management implantable device that has an intravascular device body, and one or more chemical sensors coupled with the intravascular device body. A drug eluting substance is disposed at a location including at least one of on, directly adjacent, or near the one or more chemical sensors, where the drug eluting substance prevents fibrotic growth on the one or more chemical sensors.

Abstract: A pacemaker provides multi-chamber pacing with a pacing interval that can be programmed and adapted in response to cardiac output measurements for a given patient. In a typical embodiment, the pacemaker may provide pacing stimuli to both ventricles of a heart. In addition, the invention may include a measurement device that incorporates first and second blood oxygen saturation sensors for deployment in the left and right ventricle. The oxygen saturation sensors provide a differential measurement that can be used to calculate cardiac output in accordance with the Fick method. The oxygen saturation sensors may be carried by a common trans-septal lead that positions one of the sensors proximate the right ventricle and the other sensor proximate the left ventricle. Alternatively, the oxygen saturation sensors may be deployed via separate leads. Whether single or dual leads are used to carry the oxygen saturation sensors, a respective lead may optionally carry electrodes for sensing, pacing, or both.

Abstract: A cardiac stimulation device and method monitor and store discrepancies in sensor indicated rates determined from two or more sensors generating signals related to metabolic demand. One feature included in the present invention is a sensor cross-check record that stores the time, duration and sensor indicated rates whenever individual sensor indicated rates differ by more than a discrepancy threshold. This record allows a clinician to monitor an abnormal patient condition or determine if a sensor is not functioning properly or is programmed sub-optimally. Another feature provided by the present invention is a sensor cross-check histogram in which sensor indicated rate differences are stored. Histogram data aids the clinician in selecting programmable operating parameters that control the calculation of sensor indicated rates and the rate response of the cardiac stimulation device.

Abstract: An oxygen monitoring system measures the oxygen concentration in a patient's blood for use as a physiological control parameter in rate responsive pacing. The oxygen monitoring system includes an oxygen monitoring circuit embedded in a cardiac stimulation lead and monitors the blood oxygen in a patient's venous system that passes through and into the lead. The oxygen monitoring circuit includes a working electrode, a counter electrode, a reference electrode and an IC chip electrically interconnected between the electrodes and programmed to carry out an oxygen concentration measuring process. Oxygen surrounding the electrodes causes current to flow between the electrodes and the IC chip varies the value of current generated by a current source coupled between the working electrode and counter electrode in a manner to maintain the voltage between the working electrode and reference electrode at a preselected value. The variation of the current source value is a direct measure of the blood oxygen concentration.

Abstract: The subject invention relates to the detection, diagnosis and risk stratification of clinical events such as acute coronary syndrome, in patients with signs and symptoms of suspected cardiac origin. In one embodiment, a clinical event in a patient is diagnosed by obtaining the patient's ECG, and at least one in vitro diagnostic assay, preferably an assay for a marker of ischemia, and optionally in vitro diagnostic assays for necrotic markers or other cardiac indicators, and combining the foregoing results in an algorithm to provide a diagnosis or a risk stratification of the clinical condition.

Abstract: T-wave amplitude and QT interval are derived from patient cardiac signals. Then blood glucose levels are determined based on a combination of the T-wave amplitude and the QT interval. By using a combination of both T-wave-based and QT interval-based signals, blood glucose levels can be reliably detected throughout a wide range of blood glucose levels. Once the blood glucose level has been detected, the implanted device compares the blood glucose level against upper and lower acceptable bounds and appropriate warning signals are generated if the level falls outside the bounds. In one example, wherein an implantable insulin pump is additionally provided, the pump is controlled based on the detected blood glucose level to maintain glucose levels within an acceptable range. A calibration technique is also provided for determining patient-specific parameters for use in the detection of blood glucose levels.

Abstract: A cardiac pacemaker has a pulse generator for delivering stimulation pulses to a patient's heart and a control unit for controlling the delivery of the stimulation pulses from the pulse generator. The control unit includes an altering unit for altering the AV-delay value from a predetermined first AV-delay value to a predetermined second AV-delay value, and back to the first AV-delay value. A sensor measures a parameter related to cardiac output of the patient, the sensor measuring this parameter in a time window within a time of operation with the first AV-delay value, and in a time window within the time of operation with said second AV-delay value, and in a time window within the time of operation after the return back to the first AV-delay value. A calculation unit calculates respective average values of the parameter during each of the time windows, and a determining unit determines from these average values which of the AV-delay values results in a higher cardiac output.

Abstract: In a method and a device for electrochemical determination of the concentration of at least one dissolved chemical entity in a liquid medium, a measurement voltage U is impressed on a working electrode, in contact with the liquid medium, relative to a counter electrode, thereby causing the dissolved chemical entity to react by oxidation or reduction at the working electrode, producing a measurement evoked current. The measurement evoked current is compared to a predetermined value, and the measurement voltage U is adjusted so that the measurement evoked current is substantially equal to the predetermined value, and thus remains substantially constant during measurements. A difference &Dgr;U=U−Umin is formed, which corresponds to an oxidation/reduction reaction at the working electrode, with Umin being a minimum voltage selected as a reference level. This difference is used to calculate concentration variations of the chemical entity in the liquid.

Abstract: An implantable sensor assembly for use with an implantable medical device are disclosed. The sensor assembly preferably includes two or more physiologic sensors coupled to the medical device via a pair of lead conductors, or alternatively an oxygen sensor having certain features. The oxygen sensor permits more accurate and reliable measurement of oxygen saturation in blood masses flowing within the human body.

Abstract: An implantable sensor assembly for use with an implantable medical device are disclosed. The sensor assembly preferably includes two or more physiologic sensors coupled to the medical device via a pair of lead conductors, or alternatively an oxygen sensor having certain features. The oxygen sensor permits more accurate and reliable measurement of oxygen saturation in blood masses flowing within the human body.

Abstract: An implantable sensor assembly for use with an implantable medical device are disclosed. The sensor assembly preferably includes two or more physiologic sensors coupled to the medical device via a pair of lead conductors, or alternatively an oxygen sensor having certain features. The oxygen sensor permits more accurate and reliable measurement of oxygen saturation in blood masses flowing within the human body.

Abstract: An implantable sensor assembly for use with an implantable medical device are disclosed. The sensor assembly preferably includes two or more physiologic sensors coupled to the medical device via a pair of lead conductors, or alternatively an oxygen sensor having certain features. The oxygen sensor permits more accurate and reliable measurement of oxygen saturation in blood masses flowing within the human body.

Abstract: This invention is an implantable sensor and system capable of measuring, controlling, monitoring and reporting blood constituent levels. The implantable sensor for sensing in vivo the level of at least one blood constituent in mammalian vascular tissue having at least one source of radiation from infrared through visible light, arranged to direct the radiation at the tissue where it is affected by interaction with the tissue, and at least one detector. The invention also encompasses a device for measuring and controlling the level of a blood constituent, such as glucose or oxygen, and includes an implantable infrared source module for generating an output signal representative of the sensed infrared radiation. The system includes a processor module responsive to the output signal which performs spectral analysis of the output signal and generates a control signal. The system further includes other devices for dispensing doses of medications or controlling organ function in response to the control signal.

Abstract: A device for determining the respiration rate and/or respiration depth of a patient includes a sensor for sensing heart sounds and an analyzer for analyzing the variation of the amplitude of the sensed heart sounds to determine the respiration rate and/or respiration depth from this amplitude variation. An apparatus for monitoring the respiration of a patient includes such a device and the analyzer is arranged to determine an anomaly in the amplitude variation of the sensed heart sounds as an indication of a respiration anomaly.

Abstract: A liquid coolant supply system for supplying a liquid coolant to a thermal therapy catheter includes a sensor control unit, a liquid coolant containment unit and mounts. The sensor control unit includes a pump, a cooling device, a temperature sensor and a pressure sensor. The liquid coolant containment unit includes a sealed reservoir, a coolant-sensor interface module and a pump interface fluidly coupled to the thermal therapy catheter. The coolant-sensor interface module includes a body defining a fluid chamber, a temperature interface supported adjacent the fluid chamber within the body, and a pressure interface supported adjacent the fluid chamber within the body. The mounts removably support the sealed reservoir, pump interface, temperature interface and pressure interface of the containment unit adjacent the cooling device, the pump, the temperature sensor and the pressure sensor.

Abstract: An implantable medical device, such as a cardiac pacer, defibrillator or drug delivery system, includes a container housing the required power source and circuitry and a header portion molded or glued to the container housing. Sensors, including physiological parameter sensors as may be necessary to control and implement the operation of the implantable device, or a telemetry link, or both, are disposed and sealed within the header. The header may include electromagnetic focusing devices to enhance the performance of the sensors. The sensors may include two pulse oximetry sensors that provide differential measurements to improve detection of arterial blood flow.

Abstract: A method and apparatus for automatically optimizing a cardiac performance parameter of the heart, such as its cardiac output mean arterial pressure pO.sub.2 or pCO.sub.2. The performance parameter is optimized by periodically pacing the heart for a short period of time with stimulating pulses having a modified pacing parameter value. The intrinsic operation of the heart is monitored a majority of the time and establishes a baseline value for the cardiac performance parameter. The heart is then paced with the modified pacing parameter value during an interval that is approximately a 1:4 ratio with respect to the baseline monitoring interval. The method of the present invention can be achieved using a totally implanted pacemaker, an implanted pulse generator in combination with external equipment communicating with the pacemaker via telemetry, or by using equipment located external the patient.

Abstract: The present invention includes a body implantable lead having a multipolar proximal connector, at least a first conductor coupled to at least one stimulating electrode, a sensor for sensing at least one physiologic parameter of the body, and a second and a third conductor coupled to the sensor. The sensor is hermetically sealed in a D-shaped housing. Sensor components are mounted onto a microelectronic substrate which is advantageously placed on an inner flat portion of the D-shaped housing. End caps having sealing rings, either glass frit or metal, are used to seal the ends of the shell. A hermetic seal is easily achieved by heating the sealing material until they re-flow between the end caps and the shell. Advantageously, the sensor terminals are sized to fit snugly within a narrow bore of the end cap which is then circumferentially welded closed. The D-shaped sensor is placed on a carrier having at least two lumens.

Abstract: A rate-response pacemaker includes a plurality of sensors that each sense a physiologic-related parameter suggestive of the physiological needs of a patient, and hence indicative of the pacing rate at which the rate-responsive pacemaker should provide pacing pulses on demand. The pacemaker includes appropriate selection circuitry for selecting which of the sensor parameters or weighted combinations thereof, should be used as the sensor indicated rate (SIR) signal to control the pacing rate of the pacemaker at any given time. In a preferred embodiment, a maximum sensor rate signal (MR.sub.i) is computed for each sensor, and a maximum sensor rate (MSR) signal is defined for the pacemaker, and the SIR signal is selected as the lesser of: (i) the MSR signal; (ii) the largest of the sensed sensor parameters; or (iii) the respective MR.sub.i signals.

Abstract: An improved cardiac pacemaker system of the kind that includes an oxygen sensor implantable into a patient's blood stream along with one or two electrical conductors for use in sensing heart beat activity and in selectively applying pacing pulses to the heart muscle. In an embodiment having just one implantable conductor, the oxygen sensor is integrated into the conductor, while in an embodiment having two implantable conductors, the oxygen sensor either is integrated into one of the conductors or is connected between the two conductors, in parallel with the heart muscle. In both cases, the oxygen sensor is selectively used without adversely affecting either heart beat sensing or pacing.

Abstract: A method and apparatus for optimizing the performance of a rate-responsive cardiac pacemaker. A pacemaker is provided which is capable of obtaining and storing information about a patient's cardiac function and about a pacemaker's operation during a brief exercise interval. The data collected includes information about the number of cardiac events during each two-second interval of the exercise, as well as the percentage of paced events during each two-second interval. Data reflecting the output of the pacemaker's activity sensor output is also collected for each two second interval of the test. In addition, AV interval data for each cardiac cycle during the test is collected, this data being distinguished according to whether it reflects atrial-pace-to-ventricular-sense or atrial-sense-to-ventricular-sense AV intervals. The disclosed pacemaker is operable in conjunction with an external programming/processing unit, which receives the stored data after the exercise test is concluded.

Abstract: A sensor lead for use in conjunction with an implantable monitoring or therapeutic device. The lead is provided with a V-shaped bend near its distal end, and carries a blood parameter sensor distal to the V-shaped bend. The blood parameter sensor may be, for example, an oxygen sensor, a pulse sensor or a flow sensor. The V-shaped bend facilitates the location of the sensor in an internal jugular vein, allowing the sensor to be used to monitor blood flow from the brain.

Abstract: A pacemaker system which includes an oxygen saturation sensor located near the distal end of a transvenous pacing lead generates a cycle-by-cycle variation of oxygen saturation indicative of the mechanical pumping action of the heart. A timer is used to define a detection window after the generation of a pacing pulse. The occurrence of a detected depolarization within the detection window indicates that the pacing pulses capture the heart.

Abstract: A monitoring system for an oxygen sensing, dual-wavelength, reflectance oximetry based, rate responsive cardiac pacemaker, is capable of automatically and continually adjusting an oxygen sensor signal comparator threshold such that the effects of noise, sensitivity and drift on oximeter output signals sent to the pacemaker are minimized. A comparator and related circuitry are configured to sample and compare supply excitations for multiple oxygen sensor light sources. The comparator threshold is adjusted as a function of supply excitation for each light source independently of one another, thereby providing an oxygen sensing pacemaker with optimal noise immunity since one of the more vulnerable portions of the pacing system is the transfer of the light source signals which are susceptible to noise.

Abstract: The implantable device, of the Holter intervention type, permits the detection and the polygraphic analysis (ECG, TA, haemodynamics, resonant frequencies), of the cardiovascular parameters, especially in the active sequence of current cycles, permitting the instantaneous activation of a cardiac electrical or neurovegetative or pharmacological stimulation. The device comprises automatic adaptation means permitting the active permanent monitoring of the hearts treated, repaired by prosthesis (especially valvular, arterial or myocardial), or repaired by transgenic tissue graft (including a graft in the presence of specific growth factors such as FGF).

Abstract: The present invention includes a body implantable lead having a multi-polar proximal connector, at least a first conductor coupled to at least one stimulating electrode, a sensor for sensing at least one physiologic parameter of the body, and a second and a third conductor coupled to the sensor. The sensor is hermetically sealed in a D-shaped housing. Sensor components are mounted onto a microelectronic substrate which is advantageously placed on an inner flat portion of the D-shaped housing. End caps having glass frit sealing rings are used to seal the ends of the shell. A hermetic seal is easily achieved by heating the glass frit such that the glass frit reflows between the end caps and the shell. Advantageously, the sensor terminals are sized to fit snugly within a narrow bore of the end cap which is then welded closed. The D-shaped sensor is placed on a carrier having at least two lumens.