Cardiac Pacemakers, Inc.

Minnetronix, Inc.

Gary Thomas Seim

Victor T Chen

Hal M Propp

David L Perschbacher

Aaron R McCabe

Carlos Alberto Ricci

Blake A Hedstrom

Abhi Vase

Emily Rolfes Meyering

Michael L Favet

Ben Krehbiel

Milton M Morris

LeAnne M Eberle

Andrew P Kramer

Jack M Mondry

Lynn TeWinkel

Jeffrey E Stahmann

Jesse W Hartley

Jay A Warren

Yanting Dong

Donald Lee Hopper

Kenneth L Baker

David B Krig

Doug M Birkholz

Richard Milon Dujmovic, Jr

Allan Charles Shuros

David J Ternes

Rafael Carbunaru

Kent Lee

James O Gilkerson

Stephen B Ruble

Dan Li

Shantha Arcot-Krishnamurthy

Jason J Hamann

Ron A Balczewski

Paul Allan Haefner

Kevin John Stalsberg

Scott R Vanderlinde

Lynn H Elliott

Eric Keith Enrooth

Clayton Scott Foster

Paul F Emerson

Les Norman Peterson

Kenneth N Hayes

Michael A Querimit

Randall L McPherson

Daniel O'Brien

David L Whitehouse

Efdal Elferri

Stephen R Pitzl

Aaron Mccabe

Systems and methods for filtering materials from biologic fluids are discussed. Embodiments may be used to filter cerebrospinal fluid (CSF) from a human or animal subject. The method may include the steps of withdrawing fluid comprising CSF, filtering the volume into permeate and retentate by passing the fluid through a tangential flow filter, and returning the permeate to the subject. During operation of the system, various parameters may be modified, such as flow rate.

Tangential flow filter system for the filtration of materials from biologic fluids

Systems and methods for filtering materials from biologic fluids are discussed. Embodiments may be used to filter cerebrospinal fluid (CSF) from a human or animal subject. In an example, CSF is separated into a permeate and retentate using a tangential flow filter. The retentate is filtered again and then returned to the subject with the permeate. During operation of the system, various parameters may be modified, such as flow rate and waste rate.

Method for filtering cerebrospinal fluid (CSF) including monitoring CSF flow

An example of a method performed by an implantable medical device (IMD) to deliver a therapy to a patient may include delivering the therapy to the patient, detecting a trigger that is controlled by the patient or a caregiver to the patient, and determining if at least one feature of the IMD for responding to a trigger is enabled. The IMD may be configured to allow the patient or the caregiver to the patient to enable the at least one feature. The method may further include, when the at least one feature is enabled, automatically implementing the at least one enabled feature in response to the detected trigger, including automatically suspending the therapy in response to the detected trigger and automatically restoring the therapy after a defined period after the detected trigger.

Patient control of therapy suspension

A device comprises a cardiac contraction sensing circuit, a timer circuit, an electrical stimulation circuit, and a controller. The timer circuit provides a time duration of an atrial-atrial interval between successive atrial contractions, a ventricular-ventricular interval between successive ventricular contractions, and an atrial-ventricular (A-V) interval between an atrial contraction and a same cardiac cycle ventricular contraction. The controller includes an event detection module and a pacing module. The event detection module is configured for determining whether A-V block events are sustained over multiple cardiac cycles. The pacing module is configured for providing pacing therapy according to a primary pacing mode that includes AAI(R) mode with non-tracking VVI backup mode, and for switching the pacing therapy to a secondary tracking pacing mode if A-V block events are sustained over multiple cardiac cycles.

Reverse pacing-mode switch

Cardioprotective pre-excitation pacing may be applied to stress or de-stress a particular myocardial region delivering of pacing pulses in a manner that causes a dyssynchronous contraction. Such dyssynchronous contractions are responsible for the desired cardioprotective effects of pre-excitation pacing. A method and device for applying reverse hysteresis and mode switching to the delivery of such cardioprotective pacing are described.

Reverse hysteresis and mode switching for intermittent pacing therapy

A cardiac rhythm management (CRM) device can extract ventilation information from thoracic impedance or other information, and adjust a delivery rate of the CRM therapy. A tidal volume of a patient is measured and used to adjust a ventilation rate response factor. The measured tidal volume can optionally be adjusted using a ventilation rate dependent adjustment factor. The ventilation rate response factor can also be adjusted using a maximum voluntary ventilation (MVV), an age predicted maximum heart rate, a resting heart rate, and a resting ventilation determined for the patient. In various examples, a global ventilation sensor rate response factor (for a population) can be programmed into the CRM device, and automatically tailored to be appropriate for a particular patient.

Ventilation sensor rate response normalization and calculation

An atrial event and a ventricular event can be received, and an atrioventricular (AV) delay can be provided using information about the atrial and ventricular events. The AV delay can be increased after a first condition is satisfied to allow a heart to regain intrinsic control of ventricular activation, and changed after a second condition is satisfied to allow the heart to remain in intrinsic control of ventricular activation.

AV delay features

An implantable or ambulatory medical device can include a cardiac signal sensing circuit configured to provide a sensed cardiac depolarization signal of a heart of a subject, a respiration sensing circuit configured to provide a signal representative of respiration of the subject, and a control circuit communicatively coupled to the cardiac signal sensing circuit and the respiration circuit. The control circuit includes a tachyarrhythmia detection circuit configured to determine heart rate using the depolarization signal, determine a respiration parameter of the subject using the respiration signal, calculate a ratio using the determined heart rate and the determined respiration parameter, generate an indication of tachyarrhythmia when the calculated ratio satisfies a specified detection ratio threshold value, and provide the indication of tachyarrhythmia to a user or process.

Respiratory parameters for arrhythmia detection and therapy

Noncaptured atrial paces can result in long-short cardiac cycles which are proarrhythmic for ventricular tachyarrhythmia. Approaches are described which are directed to avoiding proarrhythmic long-short cycles. For cardiac cycles in which the atrial pace captures the atrium, a first post ventricular refractory period (PVARP) and a first A-A interval are used. For cardiac cycles in which the atrial pace does not capture the atrium, both an extended PVARP and an extended A-A interval are used. The A-A interval following a noncaptured atrial pace is extended from an atrial depolarization sensed during the extended PVARP.

Methods and systems for mitigating the occurrence of arrhythmia during atrial pacing

A system and method provide for detecting atrial arrhythmias within an implantable medical device capable of sensing and pacing at least an atrium of a heart. Arrhythmia of the atrium is detected. In response to detecting atrial arrhythmia, delivery of pacing signals to the atrium is inhibited under certain conditions. While delivery of the pacing signals to the atrium is inhibited, the detected arrhythmia of the atrium is confirmed during a period of further evaluation. Delivery of pacing signals to the atrium is enabled upon ceasing of the atrial arrhythmia. Inhibiting delivery of the pacing signals during atrial arrhythmia evaluation advantageously provides for an increase in the rate at which the detected arrhythmia is confirmed.

Atrial tachyarrhythmia detection system and method

A depolarization sensing threshold can be determined using an amplitude-limited portion of a cardiac signal received using an implantable medical device. One or more cardiac depolarizations can be detected using the cardiac signal and the depolarization sensing threshold.

Sensing threshold control to limit amplitude tracking

An implanted cardiac device detects an atrial arrhythmia and provides periodically updated atrial arrhythmia status as long as the arrhythmia is ongoing. A patient may request an indication of ongoing atrial arrhythmia status from external to the patient using a patient activator. The patient activator may include a magnet for closing a reed switch in the implanted device to provide the request or may provide the request over a telemetry link to the implanted device. The implanted device may provide the requested atrial arrhythmia status and other information in the form of an audible tone produced by the implanted device or as a message telemetered from the implanted device to the patient activator. The patient activator may include a tone detector and display for providing a visual indication of the atrial arrhythmia status indication. The magnet activator may also be employed to request or withhold atrial shock therapy.

Patient controlled atrial shock therapy

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Minneapolis, MN, United States of America

Gary Thomas Seim