Medtronic, Inc.

St. Jude Medical, Cardiology Division, Inc.

Imperception, Incorporated

Linda L Ruetz

Orhan Soykan

Carl A Schu

Martin T Gerber

Christopher M Hobot

VenKatesh R Manda

Yong Kyun Cho

Bryant J Pudil

Thomas Edward Meyer

Paul A Belk

Jeffrey A Schweitzer

Catherine R Condie

Eric Jon Voth

Charles Dennis Swerdlow

Anthony David Hill

Yuriy Malinin

Donald N Jensen

Cable Patrick Thompson

Scott Davie

Ulla Strobel

A method of determining a baseline impedance value for a first electrode in a plurality of electrodes located on a medical device for tissue contact detection includes measuring an impedance value of the first electrode generated in response to a drive signal to the first electrode. The method further includes assigning a baseline impedance value to the first electrode based on impedance values measured in a predetermined time interval and determining a confidence value associated with the baseline impedance value. The method further includes utilizing the baseline impedance value in determining contact status of the first electrode when the confidence value is at or above a predetermined threshold value.

Method and system for determining baseline electrode impedance for tissue contact detection

A location of a number of fiducial points can be computed. The fiducial points can include impedance locations of an electrode disposed on a catheter in an impedance based coordinate system and magnetic locations of a magnetic position sensor disposed on the catheter in a magnetic based coordinate system. The impedance location of the electrode in the impedance based coordinate system can be transformed into a transformed impedance location of the electrode in the magnetic based coordinate system. A magnetic location of the electrode in the magnetic based coordinate system can be determined. A determination of whether an impedance shift exists between the transformed impedance location of the electrode in the magnetic based system and the magnetic location of the electrode in the magnetic based system can be made. An electromagnetic dynamic registration can be generated between the impedance based coordinate system and the magnetic based coordinate system based on the impedance shift.

Electromagnetic dynamic registration for device navigation

A medical monitoring device for monitoring electrical signals from the body of a subject is described. The medical monitoring device monitors electrical signals originating from a cardiac cycle of the subject and associates each cardiac cycle with a time index. The medical monitoring device applies a forward computational procedure to generate a risk score indicative of hyperkalemia, hypokalemia or arrhythmia of the subject. The medical monitoring device can adjust the forward computational procedure based upon clinical data obtained from the subject.

Method and device to monitor patients with kidney disease

A dialysis device for operation in multiple modes and for maintaining a known gradient of potassium ion or other electrolyte between the blood of a patient and a dialysate fluid is described. The dialysis device is capable of being used for hemodialysis or peritoneal dialysis, and the dialysis device is capable of operation with a dialysate purification unit outside of a clinical setting or with a supply of water that can be supplied in a clinical setting. The dialysis device has a composition sensor containing a potassium-sensitive electrode for measuring a potassium ion concentration in one or more of the patient's blood and the dialysate fluid and an infusate pump operated to adjust a potassium ion concentration in the dialysate fluid based at least in part on data from the composition sensor.

Multimodal dialysis system

A method and apparatus sense a cardiac electrical signal and determine a signal quality parameter of the cardiac electrical signal. A number of shock pulses to be delivered to a patient's heart is determined in response to the signal quality parameter. Each of the shock pulses are scheduled to be delivered at a unique offset from a T-wave shock interval in one embodiment of the invention.

Determination of upper limit of vulnerability using a variable number of shocks

An implantable device having enhanced capabilities for monitoring a patient's heart rate and respiration trends over extended periods of time is disclosed. The information collected by the implantable device may be stored and telemetered to an associated external device such as a device programmer for display and analysis. Heart rates are measured by measuring the time intervals between sensed depolarizations of a chamber of the patient's heart and preceding sensed depolarizations or delivered pacing pulses. Intervals may be measured in the ventricle and/or atrium of the patient's heart. According to another aspect of the invention, an implanted impedance sensor is employed to monitor minute ventilation. The heart rate and minute ventilation data is used to develop long-term trend data used for diagnostic purposes. In one embodiment of the invention, heart interval and minute ventilation measurements are taken only during defined time periods of the night and/or day when the patient is at rest. A sensor such as an activity sensor or metabolic rate sensor may be used to confirm patient inactivity.

Method and apparatus for monitoring heart rate and abnormal respiration

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New Brighton, MN, United States of America

Linda L Ruetz