Abstract: Techniques are provided for detecting pulmonary congestion based on an increase in right ventricular (RV) stroke volume over left ventricular (LV) stroke volume. In one example, the device generates an index based on accumulated differences between RV stroke volume and LV stroke volume while RV stroke volume exceeds LV stroke volume, such that the index is indicative of an ongoing imbalance between RV and LV stroke volume. The index is compared to a suitable threshold to detect a severe imbalance indicative of pulmonary edema. Additionally, techniques are described for estimating RV and LV stroke volumes based on pulmonary artery pressure, left atrial pressure, aortic pressure, LV strain or on various intracardiac or extracardiac impedance measurements.

Abstract: In a device and a method for providing correlated measures for predicting potential occurrence of atrial fibrillation, an impedance of the patient is measured to obtain impedance information; cardiogenic data is determined from the information; respiratory data is determined from the information; at least one hemodynamic measure is calculated from the cardiogenic data and at least one apnea measure is calculated from the respiratory data; the hemodynamic and apnea measures are correlated such that the correlated measures can be utilized for predicting potential occurrence of atrial fibrillation.

Abstract: In an implantable medical device, such as a bi-ventricular pacemaker and a method for detecting and monitoring mechanical dyssynchronicity of the heart, a dyssynchronicity measure indicating a degree of mechanical dyssynchronicity of a heart of a patient is calculated. A first intracardiac impedance set is measured using electrodes placed such that the first intracardiac impedance set substantially reflects a mechanical activity of the left side of the heart and a second intracardiac impedance set is measure using electrodes placed such that the second intracardiac impedance set substantially reflects a mechanical activity of the right side of the heart.

Abstract: The present invention relates to a diamond composite comprising diamond particles embedded in a binder matrix comprising SiC and a Mn+1AXn-phase, where no diamond-to-diamond bonding are present. For the Mn+1AXn-phase n=1-3, M is one or more elements selected from the group Sc, Ti, Zr, Hf, V, Nb, Ta, Cr and Mo, A is one or more elements selected from the group Al, Si, P, S, Ga, Ge, As, Cd, In, Sn, Tl, and Pb and X is carbon and/or nitrogen.

Abstract: In a method and system for monitoring mechanical properties of a heart in a subject, multiple cardiogenic impedance values reflective of the impedance of the heart in connection with a transition from inhalation to exhalation in the subject are determined. Correspondingly, multiple cardiogenic impedance values reflective of the impedance of the heart in connection with a transition from exhalation to inhalation are determined. The impedance values are collectively processed to form a trend parameter. The value determination and processing is performed over several respiratory cycles spaced apart in time to form a plurality of trend parameters over time. The mechanical properties of the heart are monitored by processing these different trend parameters. The data collection and optionally at least a part of the data processing is performed by an implantable medical device.

Abstract: Cardiac valve events are monitored by recording a left atrial pressure (LAP) representing signal using an implantable pressure sensor (50). The LAP signal is processed in order to generate a derivative LAP signal representative of the first time derivative of the LAP signal. The opening of the aortic valve of the heart is then identified to coincide in time with a minimum in the derivative LAP signal following ventricular depolarization in a cardiac cycle.

Abstract: In an implantable medical device and a method for stimulating a heart of a patient, at least one left atrial pressure (LAP) signal over a cardiac cycle is obtained. The A-wave is identified using the LAP signal and a maximum positive rate of change of the A-wave of the LAP signal is determined. The maximum positive rate of change of the A-wave corresponds to the rate which the pressure in the atrium raises as the atria contraction forces more blood into the ventricle during the very last stage of diastole. Further, AV and/or VV delay is adjusted in response to the maximum positive rate of change of the A-wave, wherein a reduction of the maximum positive rate of change of the A-wave indicates an AV and/or VV delay providing an enhanced hemodynamic performance.

Abstract: An implantable medical device is connectable to an epicardial left ventricular lead having at least one epicardial electrode and a myocardium penetrating catheter with at least one endocardial electrode and present in a lumen of the lead. The device comprises a pulse generator controller that controls a ventricular pulse generator to generate pulses to be applied to the epicardial and endocardial electrodes. The controller uses an endocardial-to-epicardial time interval or epicardial-to-endocardial time interval to coordinate endocardial and epicardial activation of the left ventricle to thereby achieve cardiac pacing that closely mimics the natural electrical activation pattern of a healthy heart.

Abstract: A medical device having an impedance measurement circuit connected to at least two intracorporeal measurement electrodes arranged to measure the impedance of tissue inside the body of a patient. The impedance measurement circuit is adapted to apply a measurement current/voltage signal to the electrodes to measure and calculate the impedance of the measurement tissue, and to apply the calculated impedance value to a storage unit. The stored impedance values are used, by an analysis unit, to measure the amount of visceral fat of the tissue object inside the body of the patient.

Abstract: An implantable medical device comprises a signal generator for generating a current signal having a frequency in a frequency window slightly less than the ?-dispersion frequency of a tissue and applying the signal over the tissue. A signal measurer measures the resulting voltage signal and an impedance parameter is calculated from the applied and measured signal by a parameter determiner. A status monitor monitors the permeability status of cell membranes in the tissue based on this impedance parameter.

Abstract: In an implantable heart monitoring device and method, particularly for monitoring diastolic dysfunction, a control circuit (a) detects the heart rate, (b) derives information correlated to the stroke volume of the heart at the detected heart rate, and (c) stores the detected heart rate and the derived information correlated to the stroke volume in a memory. The control circuit automatically implements (a), (b) and (c) at a number of different occasions for a number of different, naturally varying heart rates, so that the memory contains information indicating the stroke volume as a function of the heart rate.

Abstract: A late potential detecting system has an implantable medical device connected to at least one cardiac lead having implantable electrodes positioned at different sites of a ventricle myocardium. A sampling unit of the implantable medical device records electrogram samples for the different implantable electrodes to get different sample sets. The electrogram samples of the sample sets are time synchronized and magnitude potential representations of the potential data of the electrogram samples are determined. The magnitude potential representations of the time synchronized electrogram samples are then co-processed and used for determining a parameter that is indicative of any late potentials of the monitored ventricle.

Abstract: An implantable coronary perfusion monitoring device for in-vivo determination of a coronary perfusion index (CPI) indicative of the coronary perfusion of a heart has a time measurement unit to determine a blood pressure reflection wave measure t indicating the timely position in the heart cycle of the maximum of a reflected blood pressure wave and in a time period starting at a preset point of time in systole and ending at a local maximum of blood pressure following aortic valve closure and, a diastolic peak pressure measurement unit adapted to determine a diastolic peak blood pressure measure DPP related to diastolic aortic peak pressure and a systolic arterial pressure measurement unit adapted to determine a systolic arterial blood pressure measure SAP related to systolic arterial pressure, and a coronary perfusion index calculating unit adapted to determine said coronary perfusion index CPI as (t·DPP)/SAP.

Abstract: In a medical device and method to monitor pulmonary artery pressure of a patient, a first parameter related to the right ventricular straight volume of the patient's is detected, and a second parameter related to the right ventricular ejection rate of the patient's heart, or related to the workload of the patient's heart, is also determined. A pulmonary pressure index is determined by combining the first and second parameters, with variations of the pulmonary pressure index indicating variations in the pulmonary artery pressure. Pulmonary artery hypertension can be monitored with such a device and method.

Abstract: A new model is provided for understanding and exploiting impedance or admittance values measured by implantable medical devices, such as pacemakers or cardiac resynchronization devices (CRTs.) The device measures impedance along vectors extending through tissues of the patient between various pairs of electrodes. The device then converts the vector-based impedance measurements into near-field individual electrode-based impedance values. This is accomplished, in at least some examples, by converting the vector-based impedance measurements into a set of linear equations to be solved while ignoring far-field contributions to the impedance measurements. The device solves the linear equations to determine the near-field impedance values for the individual electrodes, which are representative of the impedance of tissues in the vicinity of the electrodes.

Abstract: In an implantable heart monitoring device and a monitoring method, an impedance is measured across at least part of an atrium, such that variation of the impedance is related to the volume change of the atrium. Values are stored at different occasions that indicate the rate of change of the measured impedance. The stored values are determined such that, when the device is used in a living being, the variation of the stored values will be related to the variation of the speed with which the atrium is filled with blood during the atrial diastole.

Abstract: 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.

Abstract: In an implantable heart monitoring device and method, particularly for monitoring diastolic dysfunction, a control circuit (a) detects the heart rate, (b) derives information correlated to the stroke volume of the heart at the detected heart rate, and (c) stores the detected heart rate and the derived information correlated to the stroke volume in a memory. The control circuit automatically implements (a), (b) and (c) at a number of different occasions for a number of different, naturally varying heart rates, so that the memory contains information indicating the stroke volume as a function of the heart rate.

Abstract: 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.

Abstract: An implantable medical device has an impedance determiner for determining a cardiogenic impedance signal based on electric signals sensed by connected electrodes. A parameter calculator processes the impedance signal to calculate an impedance parameter representative of the cardiogenic impedance in connection with the diastolic phase of a heart cycle. This parameter is then employed by the device for monitoring acute decompensated heart failure status of a subject.