Abstract: An electrode system is provided for insertion into an ossified cochlea. The electrode system includes a first electrode array and a second electrode array, both of which are electrically connected to a suitable implantable cochlear stimulator (ICS). Each of the two electrode arrays has a plurality of spaced-apart electrode contacts along one side or surface thereof, e.g., eight to twelve electrode contacts on the first electrode array, and six to ten electrode contacts on the second electrode array. A tunnel is drilled through the ossified portion of the cochlea into which the first electrode array is snugly inserted. The second electrode array is inserted into the cochlea near the second turn thereof. Where the cochlea is fully ossified, a second tunnel is drilled through the ossified portion at the second turn. A positioner may be used with the second electrode array in order to position its electrode contacts against the modiolar wall of the cochlea.

Abstract: A system and apparatus for detecting electrode faults in a physiological activity acquisition system or device. The system includes at least one signal sensing electrode attached to the subject and a signal processor coupled to the at least one signal sensing electrode. The signal sensing electrode senses a combined signal from the subject. The combined signal has an activity portion and a carrier portion. The signal processor receives the combined signal from the electrode. The signal processor processes the combined signal and generates a noise-redeuced ECG and an electrode fault signal, if an electrode fault exists.

Abstract: An active implantable medical device, in particular a pacemaker, defibrillator, or cardiovertor having an automatic adjustment of the stimulation pulse level. This device delivers to the heart stimulation pulses of low energy for the treatment of the cardiac disorders, which stimulation pulses present a predetermined amplitude and duration (width). The amplitude of the stimulation pulses can be automatically adjusted, a capture threshold is measured at predetermined intervals, and the measured capture threshold value is used as a basis for the adjustment of the stimulation pulse amplitude. The amplitude adjustment includes a validation of the measured capture threshold value, suitable to operate a coherence test between the last capture threshold value measured and at least one of the corresponding capture threshold values previously measured. The adjustment of the stimulation pulse amplitude level is then inhibited in the event of positive result of the coherence test.

Abstract: A cardiac monitor is provided that monitors the condition of the heart of a cardiac patient and generates signals indicating one of several conditions, such as supraventricular tachycardia, ventricular tachycardia and ventricular fibrillation. In order to generate these signals, the ECG from the patient is analyzed to determine a cardiac interval and heart rate, as well as a waveform factor and a waveform factor irregularity. The waveform factor is derived from the average of the ECG amplitudes during a cardiac interval and the peak value of the ECG during the same interval. Preferably, a running average is calculated over several intervals. This waveform factor is then used to detect shockable ventricular arrhythmia. The waveform factor irregularity is indicative of the variability of the waveform factor and is used to differentiate between ventricular tachycardia and ventricular defibrillation.

Abstract: An implantable stimulation device delivers a stimulation pulse in the ventricular chamber of a patient's heart and automatically adjusts a post-ventricular atrial blanking period. The stimulation device generates a ventricular stimulation pulse to trigger an evoked response, in order to produce a ventricular far-field signal that follows a successfully captured ventricular stimulation pulse. The stimulation device further includes an atrial sense circuit that senses the ventricular far-field signal, and a control system that adaptively segments the post-ventricular atrial blanking period in a post-ventricular atrial blanking period (PVAB) which is fixed in duration, and a variable far-field interval (FFI) window.

Abstract: Multi-site cardiac pacing systems for providing pacing to multiple spaced apart sites of a patient's heart, including especially but not limited to sites in right heart chamber (RHC) and left heart chamber (LHC), in triggered pacing modes while avoiding inappropriate delivery of triggered pacing to the RHC and/or LHC on a non-refractory sense event that occurs early in the cardiac cycle.

Abstract: Soft, multi-fingered resilient robotic fingers for selectively assisting the ventricles, and in particular the left ventricle, of a weak heart to produce internal pressure and to pump blood from one or more sides, in synchrony with the natural systolic contraction of the ventricle, as well as providing arrhythmia control of a beating heart. The apparatus is microprocessor and electrically-controlled and completely implantable. The plurality of soft fingers monitor and gently squeeze the heart (systole) to enhance blood circulation and assist a weak heart. The soft fingers work in harmony, by means of a micro-processor controlled solenoid or other linear robotic actuators such as metal-hydride actuators or polymeric artificial muscles, and a resilient body or a spring, to close once the solenoid is powered electrically and quickly retract away from the heart when the solenoid is not powered.

Abstract: An apparatus and a method for taking multiple physiological signals (e.g., ECG waveforms) from different sources as input, applying multiple algorithms in its core and generating results which are exported for use in clinical studies and research. The apparatus has a built-in database and a built-in spreadsheet to provide a unified platform for all clinical research in the medical field, including, but not limited to, clinical core laboratory work and high-end clinical research.

Abstract: A temporary cardiac electrical stimulating lead is disclosed having a stimulating electrode mounted in or on an electrode mounting pad disposed at a distal end of the lead, the pad having a biodegradable adhesive disposed thereon and/or therewithin. The adhesive, and preferably also the electrode mounting pad, are capable of biodegradably dissolving over time in human body fluids. The adhesive permits the electrode mounting pad to be attached to a patient's epicardium without the use of sutures, or with fewer sutures than have heretofore been required to suitably affix an electrode mounting pad to a patient's heart. In a preferred embodiment, when the lead body is pulled away from the electrode mounting pad and removed from a patient, any portion of the electrode mounting pad and the adhesive remaining within the patient dissolves over time and disappears.

Abstract: A self-calibrating rate-adaptive cardiac pacemaker is provided. The pacemaker comprising a first measuring and processing device for detecting a first, predominantly sympathetically influenced physiological parameter and for obtaining a rate control parameter, which has a control input for controlling the functional dependency of the rate control parameter on the first physiological parameter, in particular a response factor and/or an upper limit rate; and a stimulator unit for producing and outputting stimulation pulses at a stimulation rate which is determined by the rate control parameter, having a second measuring and processing device for detecting and evaluating a second, predominantly vagally influenced physiological parameter and for outputting a calibration signal which is dependent on the evaluation result, to the control input of the first measuring and processing device.

Abstract: An implantable blood flow monitoring system for providing synchronized blood vessel flow and myocardial wall contractility data to an external monitor independent of transcutaneous leads. Synchronized electrocardiogram data allows and provides comprehensive monitoring. A means is provided for transmitting synchronized cardiac function data and blood flow data to a distant remote location to facilitate continual physician monitoring.

Abstract: A power management system and technique to manage and allocate the energy provided to various components of an implanted device during periods of low energy. The power management system includes an implantable power source delivering energy to various components within the implantable medical device, a measurement device to measure the energy of the power source, and a processor responsive to the measurement device. The processor monitors the energy level of the power source. During periods of low energy, the processor limits the energy to certain device-critical components of the implantable medical device. This minimizes the risk of damage to the power source resulting from high energy drain during periods of low energy. Further, this preserves operation of device-critical components of the implanted device during periods of low energy.

Abstract: A method and apparatus determines the presence of a cardiac pulse in a patient by evaluating a physiological signal in the patient, preferably for the presence of characteristic heart sounds. The presence of a heart sound in a patient is determined by analyzing phonocardiogram (PCG) data obtained from the patient. Analyzing the PCG data may include evaluating temporal energy in the PCG data or evaluating spectral energy in the PCG data. Evaluating temporal energy in the PCG data may include estimating a first and second energy in the PCG data and comparing the first and second energy to determine a relative change in energy between them. Evaluating spectral energy in the PCG data may include calculating an energy spectrum of the PCG data and evaluating either the energy value or the frequency of a peak energy in the energy spectrum. The presence of a heart sound may also be determined by combining an evaluation of temporal energy with an evaluation of spectral energy in the PCG data.

Abstract: Apparatus for measuring a vagal tone has a detector that detects a QRS waveform of an ECG signal and generates a pulse signal that is integrated by an integrator. The integrator output is passed, in parallel, to a high pass filter and a low pass filter. The filter outputs are passed to respective voltage controlled oscillators (VCOs). The outputs of the VCOs are combined in a phase comparator that generates an output pulse train with the pulse period being proportional to the phase differences of the input signals. The phase comparator output signal is integrated and combined with a DC signal to remove any offset for constant heart rate. The combined signal is applied to a vagal tone gauge, which connects the output into a standard linear vagal tone scale.

Abstract: Methods and apparatus for providing a sufficiently stable power to a load in an energy transfer system that transfers energy from one side of a physical boundary to another side of the boundary. In one example, a power supply and a primary winding are located on a first side of a physical boundary (e.g., external to a body), and a secondary winding and the load are located on a second side of the physical boundary (e.g., internal to the body). A primary voltage across the primary winding is regulated so as to provide a sufficiently stable output power to the load notwithstanding changes in the load and/or changes in a relative position of the primary winding and the secondary winding. One aspect of the invention relates to energy transfer methods and apparatus for use in connection with the human body. In particular, one example of the invention includes a transcutaneous energy transfer (TET) system for transferring power from a power supply external to the body to a device implanted in the body.

Abstract: A hydrodynamic blood bearing includes a piston disposed coaxially in a housing bore. The piston includes a cylindrical outer surface journal spaced from the bore to define a first radial gap for receiving blood as a bearing fluid for hydrodynamically supporting the piston. The piston includes two sets of bearing pads axially spaced apart from each other, with each set including circumferentially spaced apart pads for increasing tilt stiffness of the bearing defined by the journal.

Abstract: An implantable cardiac stimulation device including an activity/position sensor that incorporates a magnetoresistive sensor and a magnet that are positioned so as to move relative to each other in response to activity and the body position of the patient when the device is implanted in the body of the patient. In one embodiment, the sensor includes a magnetoresistive sensor that is made from giant magnetoresistive (GMR) materials. Preferably, a magnet is positioned on a flexible cantilevered beam so as to be positioned adjacent the magnetoresistive sensor. Movement of the patient results in relative movement of the magnet with respect to the magnetoresistive sensor and generates a signal having an AC component corresponding to a patient's activity and a DC component corresponding to the patient's body position.

Abstract: A mouth stabilized electrode array allows spatially encoded data to be tactily impressed upon the tongue providing an alternative to conventional visual pathways with a more compact size, lower power usage, and more convenient apparatus.

Abstract: An artificial retinal device, implanted in the subretinal space of the eye in persons with certain types of retinal blindness, induces artificial vision by electrical stimulation of the remaining viable cells of the retina. The artificial retina device includes a stimulating electrode unit preferably placed in the subretinal space, and a tail-like extension housing a distant electrical return ground electrode unit that may be placed in the vitreous cavity. The stimulating electrode unit includes an array of electrode subunits. Each electrode subunit includes one or more microphotodiodes electrically connected, for example, in series to provide increased voltage and current to its microelectrode. The stimulating electrode unit and the ground return electrode of the ground return electrode unit are preferably disposed on opposite sides of the neuroretina to allow for efficient and high resolution transretinal electrical stimulation of the neuroretinal cells.

Abstract: In a bi-ventricular pacing system, an implantable pulse generator optionally having an IPG indifferent electrode is coupled to a small diameter, unipolar, left ventricular (LV) lead and a bipolar right ventricular (RV) lead. The LV lead is advanced through the superior vena cava, the right atrium, the ostium of the coronary sinus (CS), the CS, and into a coronary vein descending from the CS to locate the LV active pace/sense electrode at a desired LV pace/sense site. An LV lead placed on an epicardial surface can substitute. The RV lead in a preferred embodiment is advanced into the RV chamber to locate RV active and indifferent pace/sense electrodes therein. Sensing of RV spontaneous cardiac depolarizations to provide a RV sense event signal and delivery of RV pacing pulses is conducted across the RV active pace/sense electrode and one of the RV or IPG indifferent pace/sense electrodes.