Patent application number | Description | Published |
20080243025 | Medical Device - In a medical device and a method for operating the medical device, it is first determined whether a patient, at whom a medical measurement is to be made, satisfied specified criteria that will ensure comparability of the measurement results obtained from the patient. Only when the specified criteria had been satisfied is an electrical bio-impedance signal obtained from the patient. The cardiac component of the electrical bio-impedance signal is extracted, and is analyzed to identify a change in a medical condition of the patient. | 10-02-2008 |
20080281373 | Implantable Heart Stimulator and Method for Operation Thereof - In an implantable heart stimulator and a method for operation thereof, stimulation pulses are delivered to a heart. The amplitude of the delivered stimulation pulses can be selectively set. For setting the amplitude, threshold searches are performed at selected time intervals. Each threshold search determines a threshold value required for achieving capture. The amplitudes of the respective stimulation pulses are set to a value that exceeds the determined threshold value by a safety margin. The safety margin is selected as a function of the selected time intervals. | 11-13-2008 |
20080294213 | Implantable Medical Device with Therapy Control - A method for operating an implantable medical device to obtain substantially synchronized closure of the mitral and tricuspid valves based on sensed heart sounds includes sensing an acoustic energy; producing signals indicative of heart sounds of the heart of the patient over predetermined periods of a cardiac cycle during successive cardiac cycles; calculating a pulse width of such a signal; and iteratively controlling a delivery of the ventricular pacing pulses based on calculated pulse widths of successive heart sound signals to identify an RV interval or VV interval that causes a substantially synchronized closure of the mitral and tricuspid valve. A medical device for optimizing an RV interval or VV interval based on sensed heart sounds implements such a method and a computer readable medium encoded with instructions causes a computer to perform such a method. | 11-27-2008 |
20080294214 | Medical Device - A method for operating an implantable medical device to control a stimulation therapy includes the steps of: sensing an acoustic energy; producing acoustic signals indicative of heart sounds of the heart of the patient over predetermined periods of a cardiac cycle during successive cardiac cycles; extracting a signal corresponding to a first heart sound (S | 11-27-2008 |
20080306565 | Medical Device - In an implantable medical device and a method and computer-readable medium for operating the medical device to detect a condition of a heart of a patient, activity level of a patient and acoustic energy in a patient are sensed, and acoustic signals are generated that are indicative of heart sounds of the patient over predetermined periods of a cardiac cycle during successive cardiac cycles. A signal corresponding to a first sound is extracted from the sensed acoustic signal of a cardiac cycle. A relation is calculated between a first signal corresponding to the first heart sound in a first activity range, and a second signal corresponding to the first heart sound in a second predetermined activity level range. The calculated relation is compared with at least one reference value to detect the condition or a change of the condition. | 12-11-2008 |
20080306566 | Implantable Medical Device with Heart Condition Detection - A method for detecting a condition of a heart of a patient using an implantable medical device including the steps of sensing acoustic signals indicative of heart sounds of the heart of the patient; extracting signals corresponding to a first heart sound (S1) and a second heart sound (S2) from sensed signals; calculating an energy value corresponding to a signal corresponding to the first heart sound (S1) and an energy value corresponding to the second heart sound (S2); calculating a relation between the energy value corresponding to the first heart sound and the energy value corresponding to the second heart sound for successive cardiac cycles; and using at least one relation to detect the condition or a change of the condition. A medical device for determining the posture of a patient and a computer readable medium encoded with instructions are used to perform the inventive method. | 12-11-2008 |
20090030470 | IMPLANTABLE HEART STIMULATION DEVICE WITH REMEDIAL RESPONSE TO ANODAL CAPTURE - An implantable heart stimulating device has a left ventricular coronary sinus electrode lead provided with a tip electrode, a right ventricular electrode lead provided with a ring electrode, and a pulse generator connected to the leads that applies stimulation pulses between the tip electrode and the ring electrode, with the tip electrode serving as the anode. A monitoring unit monitors for and detects anodal capture at the right ventricular ring electrode subsequent to a stimulation. If anodal capture is detected, either a threshold search is performed by varying the pulse width and/or pulse amplitude of stimulation pulses in order to identify stimulation pulse characteristics that avoid anodal capture at the ring electrode, or at least one further electrode is activated to function as an indifferent electrode together with the ring electrode, also in order to avoid anodal capture at the ring electrode. | 01-29-2009 |
20090076560 | Biventricular Heart Stimulator and Method of Controlling a Biventricular Heart Stimulator - In a biventricular heart stimulator and a method for controlling such a biventricular heart stimulator, successive stimulation pulses are delivered to the ventricles of a heart such that stimulation pulses in a single heartbeat cycle are respectively first delivered to the first ventricle and then to the second ventricle. Capture or loss of capture in response to stimulation pulses delivered to one ventricle is detected. As a result of a detected loss of capture, preventative measures are taken for preventing loss of capture in the other ventricle. | 03-19-2009 |
20090099614 | Method and Implantable Medical Device for Classifying Sensor Signals - In a method and an apparatus for creating hemodynamic sensor signal templates using an implantable medical device connectable to a patient heart activity of the patient is sensed in order to identify a paste or sensed sequence of events of a heart cycle. Hemodynamic sensor signals for consecutive heart cycles are sensed and the sensed hemodynamic sensor signals for consecutive heart cycles are stored. The sensed sensor signals are classified dependent on at least one predetermined heart event sequence condition. A template may be created using the classified sensor signals. | 04-16-2009 |
20090118666 | Method and implantable device for measuring hematocrit - In a method for detecting a change of a condition of a patient using an implantable medical device being connectable to the patient in at least one electrode configuration, at least one impedance measurement session is initiated to obtain at least one impedance value corresponding to an impedance of whole blood of the patient. At least one relative or absolute value of an amount of hematocrit in the blood of the patient is calculated using the at least one impedance value. A present hematocrit level is determined dependent on the at least one hematocrit value, with a change of the condition being derived from the present hematocrit level of the patient. | 05-07-2009 |
20090149908 | IMPLANTABLE HEART STIMULATING DEVICE, SYSTEM AND METHOD - In an implantable biventricular heart stimulating device, and a biventricular heart stimulating method, wherein operation takes place normally with a time VV between a pacing pulse delivered, or inhibited, by a first ventricular pacing circuit and a pacing pulse delivered, or inhibited, by a second ventricular pacing circuit, and wherein a time VV | 06-11-2009 |
20090216291 | SYSTEM AND METHOD FOR DETECTING ELECTRIC EVENTS IN CHAMBERS OF A HEART - In a system and method for detecting electrical cardiac events, and a heart stimulator embodying such a system, cardiac events are detected in respective chambers of a heart by sensing electrical signals in at least two different chambers of the heart and forming a difference signal from the sensed signals, and using the difference signal to automatically distinguish between events originating from one of the chambers and events originating in another of the chambers. At least one of the sensed signals is sensed in a coronary vein on the left atrium or the left ventricle. | 08-27-2009 |
20090281438 | HEART MONITORING SYSTEM AND METHOD - An implantable heart monitoring system includes a housing configured for implantation in a subject, at least one sensor member implanted relative to the heart of the subject to detect an electrical signal related to cardiac activity of the heart, a control circuit in the housing, and a memory accessible by the control circuit. The control circuit, from said electrical signal, derives a first value related to the volume of a first part of the heart and derives a second value related to the volume of a second part of the heart, and monitors variation of said first value over time in at least a substantial portion of a heart cycle, and monitors variation of said second value over time in said substantial portion of said heart cycle, and stores in the memory information representing the monitoring of said first and second values that represents a relationship between the first and second values in the substantial portion of the heart cycle and variation of the relationship in the substantial portion of the heart cycle. | 11-12-2009 |
20100041970 | IMPLANTABLE MEDICAL DEVICE - An implantable medical device has an oxygen sensor adapted to measure the level of oxygen in oxygenized blood, and to generate an oxygen measurement signal in dependence of the level of oxygen. The oxygen sensor is adapted to perform measurements inside the heart, of blood entering the left atrium of a patient's heart. The obtained oxygen measurement signal is compared to a predetermined threshold level and an indication signal is generated in dependence of the comparison. The, indication signal is indicative of the lung functionality of the patient. | 02-18-2010 |
20100099994 | IMPLANTABLE HEART ANALYZING DEVICE, SYSTEM AND METHOD - An implantable heart analyzing device has a housing and a control circuit located within said housing. The control circuit generates an output signal adapted to actuate an activator, which is able to make a wall of the heart deflect or vibrate. The control circuit also communicates with a sensor, which can be identical with the activator, with which the movement of the heart wall can be sensed. The control circuit executes a procedure that involves the generation of an output signal and sensing a corresponding sensor signal, and to be able to derive information concerning the tension of the heart wall. An implantable heart analyzing includes the aforementioned heart analyzing device, as well as the activator and the sensor. The heart analyzing device and the system implement a method that results in generation of the aforementioned information concerning the tension of the heart wall. | 04-22-2010 |
20100100147 | MEDICAL DEVICE FOR DETECTING ISCHEMIA AND A METHOD FOR SUCH A DEVICE - In a method and medical device for detecting an ischemic episode and to determine a location of ischemia in a heart of a patient, an impedance measuring circuit measures the impedances in the tissue between electrodes of at least one electrode configuration according to a predetermined measurement scheme and an ischemia detector evaluates the measured impedance values using at least one reference impedance image of the heart to detect changes in the measured impedances that are consistent with an ischemia and to determine a location of the ischemia to at least one region of the image. | 04-22-2010 |
20100113961 | MEDICAL DEVICE FOR DETERMINING THE POSTURE OF PATIENT - The present invention relates to a method for determining the posture of a patient. The method comprises the steps of: initiating ( | 05-06-2010 |
20100121400 | IMPLANTABLE CARDIAC DEVICE AND METHOD FOR MONITORING THE STATUS OF A CARDIOVASCULAR DISEASE - An implantable cardiac device has a heart stimulator for electrically stimulating the heart of a patient, detector that measures a physiologic parameter that is affected by the status of a cardiovascular disease associated with sympathetic activation, a signal processor that determines at least one of a low frequency, LF, and a very low frequency, VLF, Mayer wave component in the measured parameter, and analyzer that automatically analyzes the determined Mayer wave component in relation to a predetermined reference value to determine the status of the cardiovascular disease. The detector is a cardio-mechanical parameter detector that measures, as said physiologic parameter, a mechanical change in at least one of the four chambers of the heart. In a corresponding method for monitoring the status of a cardiovascular disease associated with sympathetic activation of a patient having an implantable electric heart stimulator a physiologic parameter affected by the cardiac disease is measured. At least one of a low frequency, LF, and a very low frequency, VLF, Mayer wave component in the parameter is determined, and the wave component is analyzed in relation to a predetermined reference value to determine the status of the cardiovascular disease. A mechanical change in at least one of the four chambers of the heart is measured as the physiologic parameter. | 05-13-2010 |
20100179411 | IMPLANTABLE MEDICAL DEVICE AND A METHOD COMPRISING MEANS FOR DETECTING AND CLASSIFYING VENTRICULAR TACHYARRHYTMIAS (As Amended) - In a method and implantable medical device for ventricular tachyarrhythmia detection and classification, upon detection of a ventricular tachyarrhythmia based on an electrocardiogram signal, cardiogenic impedance data representative of ventricular volume dynamics are collected and used for classifying the detected tachyarrhythmia as stable or unstable. In the latter case but typically not in the former case, defibrillation shocks or other forms of therapy are applied to combat the unstable ventricular tachyarrhythmia. | 07-15-2010 |
20100292550 | IMPLANTABLE MEDICAL DEVICE - An analyte measuring system has an implantable medical device having a signal source arranged for generating a current signal and electrodes for applying the current signal to a surrounding tissue in a subject body. The device measures a resulting voltage signal with the electrodes and calculates an impedance signal therefrom. The system comprises a signal processor arranged for generating an estimate of a concentration of an analyte in the tissue based on a spectrum analysis of the determined impedance signal. | 11-18-2010 |
20100298904 | IMPLANTABLE HEART STIMULATOR FOR MEASURING DYSSYNCHRONY USING IMPEDANCE - Implantable heart stimulator connectable to an electrode arrangement has a pulse generator adapted to deliver stimulation pulses to a heart of a subject; an impedance measurement unit adapted monitor at least one heart chamber of the heart of the subject to measure the impedance in the at least one monitored heart chamber for generating an impedance signal corresponding to the measured impedance. The impedance signal is applied to a processor where the signal is processed, according to specified criteria, and a fractionation index value is determined represented by the curve length of the impedance signal during a predetermined measurement period. The fractionation index value is a measure of different degrees of mechanical dyssynchrony of the heart. | 11-25-2010 |
20110257696 | IMPLANTABLE MEDICAL DEVICE AND METHOD FOR MONITORING SYNCHRONICITY OF THE VENTRICLES OF A HEART - In an implantable medical device and a method for monitoring ventricular synchronicity of a heart, impedance signals are measured that reflect septal wall movements and impedance amplitude peaks in the impedance signal are detected. A synchronicity index indicating a degree of synchronicity is determined based on detected impedance peaks, with at least two impedance peaks detected within a predetermined time window including a cardiac cycle or a part of a cardiac cycle indicating an increased dyssynchronicity in the ventricular contractions. | 10-20-2011 |
20120004700 | IDENTIFICATION OF PACING SITE - An implantable medical device applies an electric signal over two electrodes and measures the resulting electric signal over a candidate pair of neighboring electrodes on a lead for a first heart ventricle or over a candidate electrode of the lead and a case electrode. An impedance signal is determined for each candidate pair or electrode based on the applied signal and the measured resulting signal. A time difference between start of contraction in a second ventricle and the timing of local myocardial contraction as identified from the impedance signal at the site of the candidate pair or electrode is determined for each candidate pair or electrode. An optimal pacing electrode is selected to correspond to one of the electrodes of the candidate pair having the largest time difference or the candidate electrode having largest time difference. | 01-05-2012 |
20120184866 | IMPLANTABLE MEDICAL DEVICE AND METHOD FOR MULTISITE MEASUREMENT OF INTRACARDIAC IMPEDANCE - The present invention generally relates to an implantable medical device and method for detecting and monitoring cardiac status of a patient using simultaneous multisite measurements of the intracardiac impedance and in particular to ischemia detection using the simultaneous multisite measurements. The device comprises an impedance measuring unit being connectable to a plurality of electrode configurations including a current generating device adapted to generate a current and apply the current between two electrodes of a current injecting electrode configuration of the electrode configurations and a voltage sensing device including a plurality of voltage sensing circuits arranged in parallel. Each voltage sensing circuit being connectable to a specific voltage sensing electrode configuration of the electrode configurations and being arranged to sense a voltage over the voltage sensing electrode configuration resulting from the applied current, wherein the voltage sensing circuits are capable of sensing the resulting voltages simultaneously. The device further comprises an impedance calculating module adapted to calculate a plurality of impedance values, each impedance value being based on the applied current and a resulting voltage. | 07-19-2012 |
20120239102 | IMPLANTABLE MEDICAL DEVICE FOR CARDIAC THERAPY - An implantable medical device, IMD, ( | 09-20-2012 |
20130053915 | METHOD AND SYSTEM FOR DETERMINING PACING SETTINGS - Systems and methods for optimizing the stimulation of a heart of a patient are disclosed herein. The method comprises delivering pacing therapy to the patient according to a pacing therapy setting schedule, using specific pacing intervals via specific electrode configurations. Further, sinus rate values are recorded over at least one cardiac cycle at each pacing therapy setting and it is determined whether a sinus rate value satisfies predetermined measurement conditions, wherein sinus rate values are used for trending the sinus rate over time if the measurement conditions are satisfied. The accepted sinus rate values, i.e. values that satisfy the measurement conditions, are trended over time, wherein each trended sinus rate value is created based on recordings from at least one cardiac cycle. A preferred pacing therapy setting is determined to be the pacing therapy setting that provides a lowest sinus rate. | 02-28-2013 |
20130110187 | ISCHEMIA DETECTION | 05-02-2013 |
20130190582 | ISCHEMIC REGION DETECTION - An ischemia detecting system has an implantable medical device connectable to an LV cardiac catheter with sensors for generating sensor signals representative of the concentration of a constituent in coronary venous blood at different sites in the coronary venous system. The sensor signals are co-processed by the system to detect an ischemic region of the subject's heart based on a relation between the sensor signals. The detection of the particular ischemic cardiac region is possible by conducting the concentration monitoring on either sides of a branching vein in the coronary venous system and co-processing the sensor signals. | 07-25-2013 |
20130289641 | METHOD AND SYSTEM FOR OPTIMIZING CARDIAC PACING SETTINGS - The present invention relates generally to methods and systems for optimizing stimulation of a heart of a patient. Hemodynamical index signals reflecting a mechanical functioning of a heart of a patient are recorded at different hemodynamical states. Corresponding hemodynamical reference signals at corresponding hemodynamical states are recorded. At least one hemodynamical index parameter is extracted from the recorded hemodynamical index signals. The at least one hemodynamical index parameter is a measure of the mechanical functioning of the heart and a hemodynamical index model is created, wherein the hemodynamical index model is based on the at least one hemodynamical index parameter and a comparison between output results from the hemodynamical index model and corresponding hemodynamical reference signals. From this hemodynamical index model, a hemodynamical index can be derived, which then can be used in determining patient customized cardiac pacing settings of the cardiac stimulator. | 10-31-2013 |
20140094706 | MEDICAL DEVICE FOR POSITIONING OF A LEAD - The present invention relates generally to medical devices for electrode positioning during implantation procedures. A cardiac signal measuring device measures cardiac signals sensitive to inherent differences between cardiac tissue and blood using at least one electrode of a medical lead arranged at a distal tip of the medical lead and at least a second electrode arranged at a distance from the distal electrode and being connectable to the measuring unit. An analyzing module acquires cardiac signals measured during predetermined measurement sessions. The analyzing module determines at least one cardiac signal value based on the cardiac signals for each measurement session and analyzes changes of the cardiac signal values between different measurement sessions to determine a position of the electrode relative a tissue border. A maximum of the change of the cardiac signal values between two successive measurement sessions indicates that the electrode has reached the tissue border. | 04-03-2014 |
20140214110 | SYSTEMS AND METHODS TO MONITOR AND TREAT HEART FAILURE CONDITIONS - An implantable device monitors and treats heart failure, pulmonary edema, and hemodynamic conditions and in some cases applies therapy. In one implementation, the implantable device applies a high-frequency multi-phasic pulse waveform over multiple-vectors through tissue. The waveform has a duration less than the charging time constant of electrode-electrolyte interfaces in vivo to reduce intrusiveness while increasing sensitivity and specificity for trending parameters. The waveform can be multiplexed over multiple vectors and the results cross-correlated or subjected to probabilistic analysis or thresholding schemata to stage heart failure or pulmonary edema. In one implementation, a fractionation morphology of a sensed impedance waveform is used to trend intracardiac pressure to stage heart failure and to regulate cardiac resynchronization therapy. The waveform also provides unintrusive electrode integrity checks and 3-D impedancegrams. | 07-31-2014 |
20140257423 | METHOD AND SYSTEM FOR STIMULATING A HEART - The present invention relates generally to implantable medical devices and more particularly to systems and methods for stimulating a heart of a patient. A first ventricle is activated by delivering stimulation to at least one stimulation site, a point of time for arrival at the AV node for at least one depolarization wave resulting from the stimulation in the first ventricle is estimated and a first activation time interval substantially corresponding to the time interval required for at least one depolarization wave to travel from the stimulation site in the first ventricle to the AV node using the estimated point of time for arrival of the depolarization wave and a point of time for delivery of stimulation is computed. Thereafter, the other ventricle is stimulated by delivering stimulation to at least one stimulation site. A point of time for arrival at the AV node for at least one depolarization wave resulting from the stimulation in the other ventricle is then estimated and a second activation time interval substantially corresponding to the time required for at least one depolarization wave to travel from the stimulation site in the other ventricle to the AV node using the estimated arrival of the depolarization wave and the point of time for delivery of stimulation is computed. Based on these activation time intervals and a difference between the intervals, a pacing therapy can be determined, wherein the first ventricle is paced prior to activation of the other ventricle if the activation time difference indicates that the first activation time interval is longer than the second activation time interval and the other ventricle is paced prior to activation of the first ventricle if the activation time difference indicates that the second activation time interval is longer than the first activation time interval. | 09-11-2014 |