Abstract: An apparatus for conducting electrical energy to a part of the body (e.g. the heart) and/or for providing sensor data from the body to a device suitably includes an input lead configured to electrically interface with a medical device. A switch electrically coupled to the input lead includes first and second output terminals and a switching input that is responsive to a control signal. The switch toggles electrical energy between first and second output leads in response to the control signal to provide energy to a particular location on the part of the body. The various electromechanical switches described herein may be useful in a wide variety of applications, including many applications in the medical device field. Such switches may be useful in producing Y-adapter-type lead multiplexers for implantable devices, for example, as well as in producing switchable electrode arrays, sensor leads and the like.

Abstract: An implantable medical device and associated method control the delivery of extra systolic stimulation by determining a coupling interval, setting an extra systolic interval in response to the coupling interval; and delivering a supraventricular stimulation pulse upon expiration of the extra systolic interval. The supraventricular stimulation pulse evokes a depolarization that is conducted to the ventricles occurring at a ventricular coupling interval relative to a ventricular event.

Abstract: A method for detecting a cardiac arrhythmia from an electrocardiogram includes the steps of identifying a plurality of R-waves in the electrocardiogram during a predetermined time interval; extracting heartbeat complexes corresponding to the identified R-waves; identifying a key region within each heartbeat complex that is morphologically altered in the event of the cardiac arrhythmia; calculating a statistical measurement of an ensemble of the key regions from each of the heartbeat complexes; and determining from the statistical measurement whether the cardiac arrhythmia occurred during the predetermined time interval. An apparatus is also provided that includes a processor that is coupled to receive an electrocardiogram, and is configured in response thereof to perform the method for detecting a cardiac arrhythmia.

Abstract: A medical device performs a method for detecting atrial arrhythmias. A signal including ventricular cycle length information is sensed in a patient and used to determine each difference between successive ventricular cycle lengths occurring during a predetermined time period. Each succeeding difference is stored as a data point in a histogram, and a metric of variability of the data points of the histogram is determined. An atrial arrhythmia is detected in response to the metric crossing a threshold. The threshold is determined in response to the number of ventricular cycle lengths occurring during the predetermined time period.

Abstract: In general, the invention is directed to an IMD having a piezoelectric transformer to power a lead-based sensor. The IMD powers the piezoelectric transformer with a low amplitude signal. The piezoelectric transformer serves to convert the voltage level of the low amplitude signal to a higher voltage level to drive the sensor produced by a battery in the IMD to voltage levels appropriate for IMD operation. A piezoelectric transformer offers small size and low profile, as well as operational efficiency, and permits the IMD to transmit a low amplitude signal to a remote sensor deployed within an implantable lead. In addition, the piezoelectric transformer provides electrical isolation that reduces electromagnetic interference among different sensors.

Abstract: A micro electromechanical (MEMS) switch suitable for use in medical devices is provided, along with methods of producing and using MEMS switches. In one aspect, a micro electromechanical switch including a moveable member configured to electrically cooperate with a receiving terminal is formed on a substrate. The moveable member and the receiving terminal each include an insulating layer proximate to the substrate and a conducting layer proximate to the insulating layer opposite the substrate. In various embodiments, the conducting layers of the moveable member and/or receiving terminal include a protruding region that extends outward from the substrate to switchably couple the conducting layers of the moveable member and the receiving terminal to thereby form a switch. The switch may be actuated using, for example, electrostatic energy.

Abstract: The invention is directed to denoising techniques for electrograms, or other biomedical signals, in which wavelet transformations are used in the denoising process. For example, an electrogram can be represented by a finite set of wavelets which comprise a decomposition of the electrogram in the scale-time domain. In accordance with the invention, an electrogram can be transformed into a set of wavelets, and thresholding can be performed on the wavelets to eliminate noise while preserving the information of the electrogram. Different thresholds can be used for the wavelets in different scales for improved denoising results. If a respective threshold exceeds a wavelet coefficient, the wavelet coefficient is reduced. Following the thresholding process, the wavelets can be converted into a denoised electrogram, which can be analyzed or processed. In this manner, wavelet transformations can be exploited for effective electrogram denoising.

Abstract: The invention is directed to signal processing techniques for electrograms or other biomedical signals. In particular, the signal processing techniques make use of wavelet transformation of the electrograms. For example, an electrogram can be represented by a finite set of wavelets which comprise a decomposition of the electrogram in the scale-time domain. In accordance with the invention, wavelet analysis techniques can be used to distinguish specific phenomena in electrograms. For example, wavelet analysis can be used to distinguish between occurrences of large amplitude steep deflections, small amplitude steep deflections, and large amplitude shallow deflections of an electrogram.

Abstract: An apparatus for conducting electrical energy to a part of the body (e.g. the heart) and/or for providing sensor data from the body to a device suitably includes an input lead configured to electrically interface with a medical device. A switch electrically coupled to the input lead includes first and second output terminals and a switching input that is responsive to a control signal. The switch toggles electrical energy between first and second output leads in response to the control signal to provide energy to a particular location on the part of the body. The various electromechanical switches described herein may be useful in a wide variety of applications, including many applications in the medical device field. Such switches may be useful in producing Y-adapter-type lead multiplexers for implantable devices, for example, as well as in producing switchable electrode arrays, sensor leads and the like.

Abstract: A micro electromechanical (MEMS) switch suitable for use in medical devices is provided, along with methods of producing and using MEMS switches. In one aspect, a micro electromechanical switch including a moveable member configured to electrically cooperate with a receiving terminal is formed on a substrate. The moveable member and the receiving terminal each include an insulating layer proximate to the substrate and a conducting layer proximate to the insulating layer opposite the substrate. In various embodiments, the conducting layers of the moveable member and/or receiving terminal include a protruding region that extends outward from the substrate to switchably couple the conducting layers of the moveable member and the receiving terminal to thereby form a switch. The switch may be actuated using, for example, electrostatic energy.

Abstract: In general, the invention is directed to an IMD having a piezoelectric transformer to convert battery power to operating power. The piezoelectric transformer serves to convert voltage levels produced by a battery in the IMD to voltage levels appropriate for IMD operation. In contrast to electromagnetic transformers and charge pump arrays, a piezoelectric transformer offers small size and low profile, as well as operational efficiency. In addition, in an implantable cardiac or neurostimulation device, the piezoelectric transformer provides electrical isolation that avoids circuit-induced cross currents between different electrodes.

Abstract: In general, the invention is directed to an IMD having a piezoelectric transformer to power a lead-based sensor. The IMD powers the piezoelectric transformer with a low amplitude signal. The piezoelectric transformer serves to convert the voltage level of the low amplitude signal to a higher voltage level to drive the sensor produced by a battery in the IMD to voltage levels appropriate for IMD operation. A piezoelectric transformer offers small size and low profile, as well as operational efficiency, and permits the IMD to transmit a low amplitude signal to a remote sensor deployed within an implantable lead. In addition, the piezoelectric transformer provides electrical isolation that reduces electromagnetic interference among different sensors.

Abstract: The invention is directed to signal processing techniques for electrograms or other biomedical signals. In particular, the signal processing techniques make use of wavelet transformation of the electrograms. For example, an electrogram can be represented by a finite set of wavelets which comprise a decomposition of the electrogram in the scale-time domain. In accordance with the invention, wavelet analysis techniques can be used to distinguish specific phenomena in electrograms. For example, wavelet analysis can be used to distinguish between occurrences of large amplitude steep deflections, small amplitude steep deflections, and large amplitude shallow deflections of an electrogram.

Abstract: The invention is directed to denoising techniques for electrograms, or other biomedical signals, in which wavelet transformations are used in the denoising process. For example, an electrogram can be represented by a finite set of wavelets which comprise a decomposition of the electrogram in the scale-time domain. In accordance with the invention, an electrogram can be transformed into a set of wavelets, and thresholding can be performed on the wavelets to eliminate noise while preserving the information of the electrogram. Different thresholds can be used for the wavelets in different scales for improved denoising results. If a respective threshold exceeds a wavelet coefficient, the wavelet coefficient is reduced. Following the thresholding process, the wavelets can be converted into a denoised electrogram, which can be analyzed or processed. In this manner, wavelet transformations can be exploited for effective electrogram denoising.

Abstract: There is provided an implantable system and method for monitoring pancreatic beta cell electrical activity in a patient in order to obtain a measure of a patient's insulin demand and blood glucose level. A stimulus generator is controlled to deliver stimulus pulses so as to synchronize pancreatic beta cell depolarization, thereby producing an enhanced electrical signal which is sensed and processed. In a specific embodiment, the signal is processed to determine the start and end of beta cell depolarization, from which the depolarization duration is obtained. In order to reduce cardiac interference, each stimulus pulse is timed to be offset from the QRS signal which can interfere with the pancreas sensing. Additionally, the beta cell signals are processed by a correction circuit, e.g., an adaptive filter, to remove QRS artifacts, as well as artifacts from other sources, such as respiration.

Abstract: A system for and method of providing power to an implanted medical device within a patient is disclosed. The system (250) includes a first (262) and a second heat conduit (264) positioned within the patient. A thermoelectric device (252) is connected to the first and second heat conduits for thermally converting the temperature difference between the conduits to a voltage. A DC-DC converter (254) is connected to the thermoelectric element and increases the voltage. A storage element (256) is connected to the DC-DC converter-for receiving the increased voltage. The storage element is also connected to the implanted medical device (258), thereby providing power to the implanted medical device.

Abstract: There is provided an implantable system and method for monitoring pancreatic beta cell electrical activity in a patient in order to obtain a measure of a patient's insulin demand and blood glucose level. A stimulus generator is controlled to deliver stimulus pulses so as to synchronize pancreatic beta cell depolarization, thereby producing an enhanced electrical signal which is sensed and processed. In a specific embodiment, the signal is processed to determine the start and end of beta cell depolarization, from which the depolarization duration is obtained. In order to reduce cardiac interference, each stimulus pulse is timed to be offset from the QRS signal which can interfere with the pancreas sensing. Additionally, the beta cell signals are processed by a correction circuit, e.g., an adaptive filter, to remove QRS artifacts, as well as artifacts from other sources, such as respiration.

Abstract: There is provided an implantable system and method for monitoring pancreatic beta cell electrical activity in a patient in order to obtain a measure of a patient's insulin demand and blood glucose level. A stimulus generator is controlled to deliver stimulus pulses so as to synchronize pancreatic beta cell depolarization, thereby producing an enhanced electrical signal which is sensed and processed. In a specific embodiment, the signal is processed to determine the start and end of beta cell depolarization, from which the depolarization duration is obtained. In order to reduce cardiac interference, each stimulus pulse is timed to be offset from the QRS signal which can interfere with the pancreas sensing. Additionally, the beta cell signals are processed by a correction circuit, e.g., an adaptive filter, to remove QRS artifacts, as well as artifacts from other sources, such as respiration.

Abstract: There is provided an implantable system and method for monitoring pancreatic beta cell electrical activity in a patient in order to obtain a measure of a patient's insulin demand and blood glucose level. A stimulus generator is controlled to deliver stimulus pulses so as to synchronize pancreatic beta cell depolarization, thereby producing an enhanced electrical signal which is sensed and processed. In a specific embodiment, the signal is processed to determine the start and end of beta cell depolarization, from which the depolarization duration is obtained. In order to reduce cardiac interference, each stimulus pulse is timed to be offset from the QRS signal which can interfere with the pancreas sensing. Additionally, the beta cell signals are processed by a correction circuit, e.g., an adaptive filter, to remove QRS artifacts, as well as artifacts from other sources, such as respiration.

Abstract: There is provided an implantable system and method for monitoring pancreatic beta cell electrical activity in a patient in order to obtain a measure of a patient's insulin demand and blood glucose level. A stimulus generator is controlled to deliver stimulus pulses so as to synchronize pancreatic beta cell depolarization, thereby producing an enhanced electrical signal which is sensed and processed. In a specific embodiment, the signal is processed to determine the start and end of beta cell depolarization, from which the depolarization duration is obtained. In order to reduce cardiac interference, each stimulus pulse is timed to be offset from the QRS signal which can interfere with the pancreas sensing. Additionally, the beta cell signals are processed by a correction circuit, e.g., an adaptive filter, to remove QRS artifacts, as well as artifacts from other sources, such as respiration.