Abstract: A cardiac event and arrhythmia detection system and method detects arrhythmic cardiac activity or other information from an electrogram signal of a heart. The system senses the electrogram signal through an electrogram lead, preliminarily processes the signal, and converts it to a plurality of discrete digital signals, each of which represents the magnitude of the electrogram signal at a prescribed sample time. The discrete digital signals are applied to both a cardiac event detector which has a dynamic threshold which is programmably adjustable so that T-waves are not sensed and a morphology detector. The morphology detector detects selected changes in the morphology (shape) of the electrogram signal, wherein such changes automatically control the sensitivity (gain and/or threshold) used to detect cardiac events. The occurrence of a prescribed amount of change in the detected morphology over time indicates the occurrence of a prescribed arrhythmic cardiac condition.

Abstract: A wireless feedthrough assembly, for coupling leads received in the receptacles of a connector assembly to the electronic circuit within a cardiac pacemaker, includes a weld ring mounted in hermetically sealed fashion within a housing wall of the pacemaker and itself hermetically sealed to an intermediate portion of an elongated, multilayered structure. The multilayered structure includes layers of electrically insulating ceramic material on opposite sides of a planar array of printed conductors extending between a first portion of the structure within the connector assembly and an opposite second portion of the structure within the pacemaker. Connector pads at the ends of the printed conductors within the first portion are coupled to the receptacles of the connector assembly, while contact pads at the exterior of the second portion and coupled by vias to connector pads at the ends of the printed conductors are coupled to the electronic circuits within the pacemaker.

Abstract: A pacemaker operating in an AAI or AAIR mode is provided with a detector for monitoring an atrial lead and detecting cross talk or far field R-waves from the ventricle. This signal is used to detect and monitor AV nodal block and its progression in a patient. The same signal may also be used to indicate atrial capture.

Abstract: A heart pacemaker with improved detection of electrical signals which are used for triggering pacemaker functions, has a detection circuit for registering intracardial heart signals in which certain noise signals having a generally chromatic spectrum are superimposed on the signals to be detected, the detection circuit undertaking an adaptive, non-linear noise filter of those intracardial heart signals for converting the spectrum of the noise signals into an essentially white spectrum. The signals filtered by the non-linear noise filtering are supplied to a matched filter wherein correlation of these signals with a sought signal pattern takes place.

Abstract: A heart stimulator for detecting atrial tachycardia, contains a control device to which are connected an atrial detector, having a blanking period, for detecting atrial events, a ventricular stimulation unit for delivering stimulation pulses in the ventricle, a counter for generating a variable PV interval between a detected atrial event and a stimulation pulse delivered in the ventricle, a time measurement unit for measuring time between two consecutive, detected atrial events and a calculation unit which, in a test mode for determining of whether atrial tachycardia is present, is arranged to cause the counter to generate a PV interval so the PV interval plus the atrial detector's blanking period is equal to half or less than half of an adjustable threshold level PP tachycardia. The time measurement unit sends a detection signal to the control device when a defined number of measured, consecutive PP intervals is less than a defined threshold value PP for the PP interval (threshold value PP tachycardia).

Abstract: A heart stimulator has a pulse generator which periodically emits stimulation pulses, least one electrode connectable to the pulse generator and to the heart for transmitting said pulses to the heart and a respiration monitor for monitoring the respiration of the pacemaker user. The heart stimulator adapts the energy to be delivered in a stimulation pulse in response to the information acquired by the respiration monitor which indicates the current stage in the user's respiration cycle.

Abstract: A microstrip EMI shunt for an implantable medical device (e.g., an ICD) which includes a microstrip transmission line secured to an interior surface of a housing of the device, the microstrip transmission line having a first end secured to a connector wire which is electrically coupled to internal electronics of the device, and a second end which is open-circuited. The microstrip transmission line has a length n.lambda./4, where .lambda. is the wavelength of EMI (in the microstrip medium) having a selected frequency f which is desired to be shunted, and n is an odd integer .gtoreq.1. In operation, EMI of the frequency f is shunted via the microstrip transmission line prior to reaching the internal electronics of the device. Additional microstrip transmission lines having appropriately chosen lengths to shunt EMI of different frequencies can also be provided.

Abstract: A universal cable connector for use between an external system analyzer (54) and an implantable stimulation device includes a multi-conductor cable (60) and a universal connector block (52) having plurality of different sized female connectors adapted to mate with the proximal connectors of different sized implantable pacing leads (33, 34 or 38) and defibrillation leads (48, 50). The universal connector block (52) attaches to the system analyzer and enables the system analyzer to interface with whatever implantable stimulation leads are connected to the connector block, thereby allowing the system analyzer to perform desired tests, such as threshold-determining tests, using the implanted stimulation leads. An adapter cable (96) and clamp (94) are also provided that allow an electrical connection of the proper polarity to be established between an implantable stimulation device (24), e.g.

Abstract: An implantable medical apparatus includes a therapy unit which produces a medical therapy regimen which is administered by the implantable medical apparatus to a subject. The implantable medical apparatus obtains an electrical signal representing physiological activity of the subject and performs detrended fluctuation analysis on the electrical signal so as to obtain a self-similarity parameter for the electrical signal. Deviations of the self-similarity parameter from a nominal value indicate the severity of the pathology of the subject which the implanted medical apparatus is intended to treat. The self-similarity parameter can be made extracorporeally available for use by a physician to evaluate the effectiveness of a treatment program currently in place, and/or can be supplied to a control unit of the implantable medical apparatus for use in automatically adjusting the therapy regimen administered by the implantable medical apparatus.

Abstract: A cardiac stimulation device contains an electronics package having a hybrid circuit structure enclosed by a contoured lid design. The contoured lid of the electronics package has a multi-level surface structure which conforms to a multi-level design of the hybrid circuit structure. Mounting the electronics package within a housing of the cardiac stimulation device creates an isolated region formed between the contoured lid of the electronics package and an interior surface of the housing. An activity sensor, or other component of the cardiac stimulation device, may be placed within the isolated region to reduce the overall size of the device.

Abstract: An implantable pacing lead with a reinforcing sheath covering a portion of the lead body to prevent physical stress damage to the lead body. The reinforcing sheath includes a metal coil or ribbon encased in a biocompatible polymer which is positioned about a portion of the lead body.

Abstract: An adjustable single-pass A-V lead for cardiac pacing comprises a ventricular lead body with a ventricular electrode at its distal tip, and an atrial sheath slidably mounted over the ventricular lead body. An atrial electrode is located on a portion of the atrial sheath that is adapted to form an outwardly-extending atrial bow. A distal portion of the sheath is configured to resist sliding over the ventricular lead body so that the atrial bow is formed when a tubular, proximal portion of the sheath is advanced distally relative to the ventricular lead body. The longitudinal distance between the atrial and ventricular electrodes can be adjusted during implantation by withdrawing the sheath proximally relative to the ventricular lead body.