Cardiac Pacemakers, Inc.

Medtronic, Inc.

Cvrx, Inc.

Russell E Anderson

Jeffrey E Stahmann

Randy W Westlund

Bruce Alan Tockman

Rene H Wentkowski

Robert S Kieval

Eric G Lovett

John Charles Stroebel

Nadim Yared

Steve Check

James D Reinke

Eric John Wengreen

David J Yonce

Robert A Betzold

James W Busacker

Robert John Schuelke

Gregory L Sundberg

Terrence R Hudrlik

Kevin L Bright

Ren Zhou

David W Hoffman

Virginia De La Riva

Joseph P Pagliolo

Richard F Weispfenning

Kirk S Vadnais

Stuart P Lahtinen

A method for allowing cardiac signals to be sensed and pacing pulse vectors to be delivered between two or more electrodes. In one embodiment, cardiac signals are sensed and pacing pulse vectors are delivered between at least one of a first left ventricular electrode and a second left ventricular electrode. Alternatively, cardiac signals are sensed and pacing pulse vectors are delivered between different combinations of the first and second left ventricular electrodes and a first supraventricular electrode. In addition, cardiac signals are sensed and pacing pulse vectors are delivered between different combinations of the first and second left ventricular electrode, the first supraventricular electrode and a conductive housing. In an additional embodiment, a first right ventricular electrode is used to sense cardiac signals and provide pacing pulses with different combinations of the first and second left ventricular electrodes, the first supraventricular electrode and the housing.

Pacing and sensing vectors

A method of determining one or more physiological parameter of a patient by providing a plurality of implantable electrodes proximate a blood vessel of the patient, applying a measurement signal through the plurality of electrodes, the measurement signal having a known parameter, obtaining a resultant signal through the plurality of electrodes, the resultant signal having a resultant parameter, calculating vascular impedance based on the measurement signal and the resultant signal, and calculating a physiological parameter based on the vascular impedance. In some embodiments, the physiological parameter is utilized to modify a therapy signal controlling therapy delivered to the patient.

Measurement of patient physiological parameters

A method for allowing cardiac signals to be sensed and pacing pulse vectors to be delivered between two or more electrodes. In one embodiment, cardiac signals are sensed and pacing pulse vectors are delivered between least one of a first left ventricular electrode and a second left ventricular electrode. Alternatively, cardiac signals are sensed and pacing pulse vectors are delivered between different combinations of the first and second left ventricular electrodes and a first supraventricular electrode. In addition, cardiac signals are sensed and pacing pulse vectors are delivered between different combinations of the first and second left ventricular electrode, the first supraventricular electrode and a conductive housing. In an additional embodiment, a first right ventricular electrode is used to sense cardiac signals and provide pacing pulses with different combinations of the first and second left ventricular electrodes, the first supraventricular electrode and the housing.

Low voltage conductors in a lead assembly share a lumen in a tube and are separated from adjacent conductors in the tube by an insulative layer. In an embodiment, low voltage conductors are combined with high voltage conductors. In another embodiment, low voltage conductors are combined with other low voltage conductors.

Strategic combination of conductors in a lead assembly for a medical device

A method and apparatus for measuring the lead impedance of a medical lead used with an implantable medical stimulator which relies upon a count of the number of switching cycles of a switching converter power supply to replenish the energy delivered from an pacing capacitor in delivering a stimulating pulse to tissue.

Method and apparatus for measuring lead impedance in an implantable cardiac rhythm management device

Two mechanisms work together to adjust two variables independently so that the gain of an input amplifier used to find physiologic signals in an implantable medical device can be automatically adjusted to enhance the signal to noise ratio of the electrical input to said amplifier. The first determines whether there has been too long a time between senses found in the body's electrical input to the amplifier and if true, and no other conditions override that consideration, it adjusts the value of a long term average parameter which is used as a referent parameter to adjust the actual parameter that is used as the referent for making either a threshold level adjustment or gain change, depending on the structure of the particular design's circuitry and/or software. One set of adjustments to the gain referent parameter depends on the relative size of the long term average parameter and the gain referent parameter. The mechanisms preferably employ counting registers, the one which adjusts the gain referent having a process to weight input signals such that those of different types get different weights, and the other mechanism only accepting certain of the input signals. Input signals to the two mechanisms can be either physiologically based or from stimulation pulses issued from an implanted device, such as, for example a pacemaker.

Method for automatically adjusting the sensitivity of cardiac sense

A tissue electrical stimulator and electrical pulse waveform are described. The stimulator or pulse generator may deliver the pules preferably through an endocardial electrode to pace a heart but could be used for other tissue such as nerves or to deliver defibrillation pulses through other means. A preferred circuit is described employing timing of a gate voltage level on an output transistor for the discharge capacitor(s) of the pulse generator. The waveform has a leading edge starting above zero volts and ramps upward for an initial fraction until a saturation voltage is reached and then ramps downward.

Low energy pacing pulse waveform for implantable pacemaker

A pacemaker having two bipolar leads, one atrial, one ventricular, each with TIP and RING electrodes, configured as for conventional bipolar pacing/sensing in both chambers. Switching circuitry in the pacemaker is operable to select from among various possible sensing configurations, including one configuration in which sensing is performed between the ring electrodes of the respective pacing/sensing leads. Pacing is preferably performed in a conventional unipolar configuration in each chamber, from the respective tip electrodes. The 'ring-to-ring' EGM signal is applied to filtering and EGM amplifier circuitry, and then provided to a telemetry system for transmission to an external receiver. The ring-to-ring EGM signal possesses the high resolution properties of conventional intracardiac signals, and is relatively unaffected by the after-potentials and tissue polarization effects that arise when the same lead is used for pacing and sensing. Additionally, the ring-to-ring EGM signal is a composite of atrial and ventricular electrical signals, and thus has an appearance similar to that of surface ECGs.

Ring-to-ring cardiac electrogram pacemaker

A switched capacitor ventricular sense amplifier for an implantable pulse generator having unique control of the switching clock for minimization of transients during the period just preceding, during and following an atrial paced event. The timing is modified to discontinue switching during this period. This ensures that transients occurring as a result of functionally disconnecting and subsequently reconnecting the sensing lead with the sense amplifier are not propagated within the switched capacitor bandpass filter. An alternative approach is to increase the clocking rate during the blanked period to ensure that the transients created by the atrial pace or by disconnecting and reconnecting the sensing lead are rapidly processed by the switched capacitor bandpass filter and that processing is completed shortly following the atrial paced event. This alternative approach requires a gate at the sense amplifier output to disable propagation of any transients processed.

Bandpass filter clock control

Growing community of inventors

Marine on St. Croix, MN, United States of America

Russell E Anderson