Abstract: A programmable pacemaker system, having a programmer which has the capability of making software control modifications to a family of pacemakers types which can be software modified with different control functions. The programmer carries manual data relating to the manual corresponding to each pacemaker type. Whenever a new control software release is loaded into the programmer, an accompanying new manual portion is also loaded into programmer memory; the programmer can determine what manual portion or portions are superseded if the new control software is downloaded into any one of the respective different pacemaker types of the family. Whenever a programmer is used to download a new control routine into an implanted pacemaker, the programmer automatically provides the option to display and/or print a new applicable manual portion; superseded manual portions due to downloading operations; and/or the entire manual corresponding to the pacemaker as modified by the downloading operation.

Abstract: The present invention provides a pacing system with a lead having a fixation element for providing stable fixation relative to the patient's SVC, preferably providing for positioning of the atrial electrodes near the sinus node. In a first embodiment, an adjustable loop is provided for engaging the inside wall of the SVC so as to obtain fixation of the lead just above the sinus node. Other embodiments utilize tine arrangements for providing the fixation relative to the SVC.

Abstract: Method and apparatus for providing on-demand stimulation of the gastrointestinal tract. The apparatus features an implantable pulse generator which may be coupled to the gastric system through one or more medical electrical leads. In the preferred embodiment the leads couple to the circular layer of the stomach. The pulse generator preferably features sensor for sensing abnormalities in gastric electrical activity. The pulse generator further features means for recognizing the type of gastric abnormality sensed. That is means for detecting whether gastric arrhythmia, bradygastria, dysrhythmia, tachygastria or retrograde propagation or uncoupling are present. If any of these gastric rhythm abnormalities are detected, then the pulse generator features means for emitting stimulation pulse trains to the gastric system to treat the detected gastric rhythm abnormalities. The stimulation pulse trains may take many forms and may be emitted for various periods of time.

Abstract: The present invention is directed to a medical electrical lead having active fixation which features an improved fixation helix. In particular the present invention is a medical electrical lead having a fixation helix which features microgrooves. The microgrooves are dimensioned so as to minimize the foreign body response of the tissue into which the helix is implanted. The microgrooves preferably consist of a series of grooves parallel to the longitudinal axis of the helix, each groove has a depth of between approximately 0.1 to 30 microns, preferably between approximately 0.1 and 3, with 1 micron preferred; a width of between approximately 0.1 to 30 microns, preferably between approximately 0.1 and 3, with 1 micron preferred; and is spaced apart from every other groove by a distance of between approximately 0.1 to 30 microns, preferably between approximately 0.1 and 3, with 1 micron preferred.

Abstract: An ambulatory data recorder having a selectable device control interface. The selectable device control interface permitting a selection to be made between a first device control interface, in which the full device control set is accessible, and a second control interface, in which only a partial amount of the device control set is accessible. Typically the first control interface is intended for use by physicians and the second control interface is intended for use by patients. The selectable device control interface is provided by a combination of device controls and a moveable device cover. The cover moveable from a first opened position in which the full device control set is accessible and a second closed position in which only a partial amount of the device control set is accessible. Preferably the cover permits operation of at least one of the device controls regardless of its position.

Abstract: The present invention provides a cardiac pacing system with a DDD lead with pre-stressed curvilinear portions, the lead being able to adapt to heart movement and size so as to provide more stable positioning with respect to the atrium. The lead has at least three such pre-stressed curvilinear portions positioned to adapt to the patient's heart and to absorb movement due to contractions so as to maintain atrial electrodes in a stable position with respect to the atrial wall.

Abstract: A transvenous lead specifically designed for multi-chamber electrical stimulation or sensing. In a first embodiment the lead features one or more electrodes for communication with the right atrium as well as one or more electrodes for communication with either or both of the left chambers of the heart. The lead further features structures to simultaneously bring the first electrode into contact with a first chamber, such as the right atrial wall and the second electrode into contact with a particular portion of the coronary sinus wall, to electrically access the left atrium or ventricle. In the preferred embodiment the lead body has varying flex or stiffness characteristics along its length between each of the electrodes.

Abstract: A pacing system and method for providing multiple chamber pacing of a patient's heart, and in particular, pacing programmed for treatment of various forms of heart failure. The system utilizes impedance sensing for determining optimum pacing parameters, e.g., for pacing the left ventricle so that left heart output is maximized. The impedance sensing also is used for determination of arrhythmias or progression of heart failure. Impedance sensing is provided for between selected pairs of the four chambers, to enable optimizing of information for control and diagnosis. In a preferred embodiment, impedance measurements are obtained for determining the timing of right heart valve closure or right ventricular contractions, and the timing of delivery of left ventricular pace pulses is adjusted so as to optimally synchronize left ventricular pacing with the right ventricular contractions.

Abstract: There is provided a pacemaker system with capture verification and threshold testing, in which the pacemaker adjusts the post-stim pulse portion of a triphasic pulse to minimize polarization, and waits after each change in delivered pace pulses for a stabilization interval, in order to enhance capture verification. The threshold test utilizes a pace pulse pair, comprising a prior search pulse which is varied during the test, and the regular pacing pulse which is above threshold. When delivery of the pulse pairs is initiated, the search pulse is adjusted to optimize polarization, and the pacemaker waits for a predetermined stabilization period of time in order to allow for minimum polarization and to optimize capture detection. The search pulse is increased incrementally in output value toward threshold, and following each such increase the pacemaker waits for a stabilization interval. The pacemaker detects when capture is achieved by the search pulse, thereby providing an indication of threshold.

Abstract: A system to provide cardiac assistance to a patient's heart. The system includes a pulse generator adapted to be coupled to patient's heart and adapted to be coupled to a skeletal muscle ventricle (SMV). The system further includes a sewing ring adapted to be coupled to the SMV and adapted to be coupled to the patient's circulatory system, the sewing ring has a first annular ring and a second annular ring, the first and second annular rings having means for limiting the formation of tissue fibrosis in the vicinity of the first and second annular rings. In the preferred embodiment this comprises means for being more flexible at a distal end than a proximal end, which is accomplished by providing a series of holes in each of the rings. The holes preferably have a range of diameters, the holes located furthest away from the distal end of each ring have smaller diameters than compared to those holes located nearer to the distal end of the same ring.

Abstract: The present invention is a system for ablating tissue within a body, the system having: an energy source providing a level of energy which is non damaging to the cellular structures of the body tissue, a catheter coupled to the energy source, the catheter having an electrode; and means for sensing the temperature of the electrode while also sensing the amount of energy which is non damaging to the cellular structures of the body tissue is delivered to the electrode, the sensing means coupled to the catheter and coupled to the energy source wherein the degree to which the electrode contacts the heart tissue (e.g. no contact, moderate contact, good contact or excellent contact) may be determined.

Abstract: An electrocautery instrument is provided with a hollow electrode having a source of conductive fluid coupled to a proximal end thereof. Conductive fluid is communicated through said electrode and expelled out of the distal end thereof during electrocautery, forming a "virtual electrode." The infused conductive liquid conducts the RF electrocautery energy away from the conductive electrode, thereby displacing the region of thermal generation and reducing the extent of burns and perforations caused by conventional electrocautery electrodes. In one embodiment, the electrode is partially disposed within and extends distally out of a retractable suction tube, such that smoke and fluid are aspirated from the electrocautery site. When the suction tube is fully advanced, the electrode is concealed therein, enabling suction without electrocautery to be performed.

Abstract: A system and method are provided for inducing ventricular tachycardia in a patient to enable testing to determine the optimum parameters for anti-tachycardia stimulation. The implantable device provides for overdrive pacing of the heart for a short sequence, followed by delivery of a series of pulse pairs. Each pulse pair has a first stimulus pulse delivered at the same or similar overdrive rate, and an inducing pulse which is delivered in timed relation to the evoked T-wave, preferably during the falling edge portion of the T-wave. In this way, each cycle the inducing pulse is timed for efficaciously inducing tachycardia. The timing of the inducing pulse is enhanced by near field sensing of the T-wave at about the location where the pulses are delivered, preferably using bipolar sensing and/or sense circuitry designed to recover the signal with an optimum time response.

Abstract: An implantable medical pump featuring a low power multi-stable valve. In particular, the present invention features a valve constructed using an electrolytic fluid, the fluid releasing a gas when subject to an electronic current, the same gas absorbed again by the fluid when such current is removed. The fluid is further housed within an uniquely designed actuation chamber such that the out-gassing of the fluid deforms the membranes defining the chamber. The membranes, in turn, are positioned such that this deformation will inhibit or completely restrict the flow pathway between the reservoir and ultimately the patient. Through such a design a valve is provided which has complete variability in the possible flow rates but which uses a minimal amount of electronic current. Moreover, the valve has the additional safety feature of being in the normally closed position when no energy is provided.

Abstract: A two-staged venous cannula is disclosed having an angled bend near the distal end. In a preferred embodiment, the angle is a right angle. The angle bend allows the cannulation to take place near the junction of the inferior vena cava and the right atrium instead of higher in the right atrium. The cannula has a drainage hole at the apex of the angled bend to act as a blood collection port and a drainage hole at the distal end of the cannula to drain the inferior vena cava. The two-stage venous cannula is made of a rigid material at its distal end so that the distal end of the cannula may be easily inserted into the patient's heart through the right atrium. The disclosed cannula keeps the cannula away from the aorta, allows the cannula to exit the superior vena cava at an angle more perpendicular to the axis of the superior vena cave and allows the cannula to be used in minimally invasive surgical procedures where size and access restrictions often make it difficult to place and maintain such devices.

Abstract: There is provided an implantable cardiac pacing system or other cardiac monitoring system, having an enhanced capability of classifying intracardiac signals through a combination of DSP techniques and software algorithms. The implantable device has one or more DSP channels corresponding to different signals which are being monitored. Each DSP channel provides for amplification of the incoming signal; conversion from analog to digital form; digital filtering of the converted signals to provide filtered signals; operating on the filtered signals to provide slope signals; determining from the filtered and slope signals whenever an intracardiac event has been detected, e.g., R wave, P wave, etc.; and signal processing of the filtered and slope signals for a predetermined analysis interval after threshold crossing, for generating a plurality of signal parameters.

Abstract: A method for making a medical device having a biomolecule immobilized on a substrate surface is provided. The method includes coating the substrate surface with an amino-functional polysiloxane; and contacting the amino-functional polysiloxane coated surface with a biomolecule under conditions effective to immobilize the biomolecule.

Abstract: An anticonstipation apparatus, and method, that may include using an implanted stimulus generator that may supply electrical stimuli to the muscles associated with a target portion of the patient's gut, from the esophagus to the anus, through an electrical lead and several pairs of electrodes. The electrical stimuli may be provided to nerves in the autonomic nervous system that are associated with the muscles, or the stimuli may be provided directly to the muscles themselves. The stimuli may be provided sequentially, in a proximal to caudad direction, in order to initiate, enhance or artificially produce peristalsis in the gut's target portion in a proximal to caudad direction. If the gut's target portion is in the descending colon, such stimulation may be coordinated with similar stimulation of the muscles associated with the rectum and anus. A sensor may be provided to detect when the target portion is experiencing constipation.

Abstract: An ambulatory recorder which features a method of configuring the size of data subject to loss in volatile memory. The recorder of the present invention determines how many processor sampling cycles it will take to fill the memory buffer. As discussed above this will vary a great deal and will directly depend upon the programmed parameters, e.g. number of channels to be sampled and the various sampling frequencies. The device then determines the amount of time this number of processor sampling cycles will take. If this amount of time is greater than a pre-selected amount of time, then the number of sampling cycles is reduced to be less than the pre-selected amount of time. The recorder uses these calculations to thereby schedule the transfer of data from the volatile memory to the non volatile memory. Through such an operation the data in the memory buffer subject to loss is limited to only a pre determined amount of time, i.e.

Abstract: A system and method for locating an implantable medical device. The system consists of a flat "pancake" antenna coil positioned concentric with the implantable medical device target, e.g. the drug reservoir septum. The system further features a three location antenna array which is separate from the implantable device and external to the patient. The antenna array features three or more separate antennas which are used to sense the energy emitted from the implanted antenna coil. The system further features a processor to process the energy ducted by the antenna array. The system senses the proximity to the implant coil and, thus, the implant device by determining when an equal amount of energy is present in each of the antennas of the antenna array and if each such ducted energy is greater than a predetermined minimum. When such a condition is met, the antenna array is aligned with the implant coil. Thus the needle port through the antenna array is lined up with the septum of the drug reservoir.