Abstract: A heart monitoring system comprises a ventricular sensing stage sensing excitation or contraction of ventricular myocardium, an activity sensor unit determining a signal reflecting a patient's physical activity, a ventricular impedance or conductance measuring module, said modules comprising a current source unit adapted to provide a sub-threshold excitation current to the myocardium and comprising an impedance or conductance measurement unit for measuring the resulting voltage on said electrode at the myocardium, a signal generator module, a filter module, a memory, a control unit adapted to derive single measures |?Z| of magnitude of impedance or conductance change over a preset sample time interval, determine the variability TARVI in the impedance or conductance change, compare this variability and the activity sensor output signal with a threshold and recent history, determine if sleep disturbed breathing (SDB) is present, and log the SDB episode in the memory device.

Abstract: An implantable medical device that continuously measures the patient's intracardiac ventricular impedance. Extracts cardiac performance information based on the intracardiac impedance, including amplitude, timing and variability of cardiac contraction function. The device records and analysis trends in the performance information. The device identifies changes, which exceed the selected threshold limits. In the event of an incipient crisis, the device transmits an alert message.

Abstract: Heart stimulating system for stimulating at least a ventricle of a heart including: stimulation pulse generator adapted to generate stimulation pulses and connected to a ventricular stimulation electrode for delivering stimulation pulses, atrial sensing stage connected to an electrode for picking up potentials inside an atrium and adapted to sense an excitation or contraction of atrial myocardium, ventricular sensing stage connected to an electrode for picking up potentials inside a ventricle and adapted to sense an excitation or contraction of ventricular myocardium, memory for AV-delay values, a control unit adapted to trigger said stimulation pulse generator to generate ventricular stimulation pulses timed based on AV-delay values stored in said memory and to acquire atrioventricular interval samples, and atrioventricular interval timing analyzing unit for receiving atrioventricular interval samples from said control unit and adapted to generate at least one histogram based on said atrioventricular interva

Abstract: Implantable medical device with an impedance determination unit with constant current/voltage source having current feed terminals connected to electrodes for intracorporal placement which generates measuring current pulses having constant current/voltage, for causing a current through a body via intracorporally placed electrodes, a measuring unit for measuring voltage/current strength of voltage/current fed through body, an impedance value determination unit connected to the current/voltage source and adapted to determine an impedance value for each measuring current pulse, and an impedance measuring control and evaluation unit connected to the impedance determination unit which controls the unit and evaluates a sequence of consecutive impedance values, the impedance determination unit further adapted to determine at least intrathoracic and intracardiac impedance values for same period of time, the intrathoracic values sampled with a lower sampling rate than the intracardiac values.

Abstract: An implantable medical device that continuously measures the patient's intracardiac ventricular impedance. Extracts cardiac performance information based on the intracardiac impedance, including amplitude, timing and variability of cardiac contraction function. The device records and analyses trends in the performance information. The device identifies changes, which exceed the selected threshold limits. In the event of an incipient crisis, the device transmits an alert message.

Abstract: Heart stimulating system for stimulating at least a ventricle of a heart including: stimulation pulse generator adapted to generate stimulation pulses and connected to a ventricular stimulation electrode for delivering stimulation pulses, atrial sensing stage connected to an electrode for picking up potentials inside an atrium and adapted to sense an excitation or contraction of atrial myocardium, ventricular sensing stage connected to an electrode for picking up potentials inside a ventricle and adapted to sense an excitation or contraction of ventricular myocardium, memory for AV-delay values, a control unit adapted to trigger said stimulation pulse generator to generate ventricular stimulation pulses timed based on AV-delay values stored in said memory and to acquire atrioventricular interval samples, and atrioventricular interval timing analyzing unit for receiving atrioventricular interval samples from said control unit and adapted to generate at least one histogram based on said atrioventricular interva

Abstract: Implantable medical device with an impedance determination unit with constant current/voltage source having current feed terminals connected to electrodes for intracorporal placement which generates measuring current pulses having constant current/voltage, for causing a current through a body via intracorporally placed electrodes, a measuring unit for measuring voltage/current strength of voltage/current fed through body, an impedance value determination unit connected to the current/voltage source and adapted to determine an impedance value for each measuring current pulse, and an impedance measuring control and evaluation unit connected to the impedance determination unit which controls the unit and evaluates a sequence of consecutive impedance values, the impedance determination unit further adapted to determine at least intrathoracic and intracardiac impedance values for same period of time, the intrathoracic values sampled with a lower sampling rate than the intracardiac values.

Abstract: A heart monitoring system comprises a ventricular sensing stage sensing excitation or contraction of ventricular myocardium, an activity sensor unit determining a signal reflecting a patient's physical activity, a ventricular impedance or conductance measuring module, said modules comprising a current source unit adapted to provide a sub-threshold excitation current to the myocardium and comprising an impedance or conductance measurement unit for measuring the resulting voltage on said electrode at the myocardium, a signal generator module, a filter module, a memory, a control unit adapted to derive single measures |?Z| of magnitude of impedance or conductance change over a preset sample time interval, determine the variability TARVI in the impedance or conductance change, compare this variability and the activity sensor output signal with a threshold and recent history, determine if sleep disturbed breathing (SDB) is present, and log the SDB episode in the memory device.