Pacesetter, Inc.

Siemens-pacesetter, Inc.

Other

Pacestter, Inc.

Jeffery D Snell

Gene A Bornzin

Brian M Mann

Laurence S Sloman

Rupinder Bharmi

Thomas G Levin

John W Poore

Peter Boileau

Harold C Schloss

Xiaoyi Min

Jason A Sholder

Roy B Medlin

Yougandh Chitre

Joseph J Florio

Jong Kil

Euljoon Park

Jong Gill

Jay Snell

Kerry A Bradley

Paul A Levine

John R Helland

Eric Steven Fain

James D Causey, Iii

Nils Holmström

Kevin L Morgan

Annapurna Karicherla

Anne M Shelchuk

Allan R Schwartz

Jeffrey D Konopka

Kenneth Valikai

Bing Zhu

Bruce A Morley

Robert E Smith, Jr

Katie Hoberman

Gregory C Bevan

Laleh Jalali

Mohssen Fard

Leslie S Miller

J Kelly Fox

Zifei Wang

Azita M Rahbari

George E Eisinger

Euljoon Park Park

A system and method provide precise detection of the time of occurrence of a cardiac event of a heart. The method comprises the steps of sensing electrical activity of the heart to generate an electrogram of the heart and applying the electrogram to an event detector having a plurality of spaced apart thresholds. The thresholds are selected such that the electrogram has an amplitude for crossing at least one of the thresholds. The method further comprises determining a characteristic identifying feature of the electrogram at each threshold crossing of the electrogram, comparing the determined characteristic identifying features to an electrogram template, and identifying the time of occurrence of the cardiac event based upon the comparison.

System and method for accurately detecting cardiac events using multi-threshold processing

During cross-chamber pacing, where anodal capture may not be desirable, pulses are applied between a cathode electrode in a first chamber and an anode electrode in a second chamber. A capture detector detects for capture of the second chamber by the pacing pulses. If capture of the second chamber persists, another electrode is selected as the anodal electrode. During single-chamber pacing, where anodal capture may be desirable, pulses are applied between a cathode electrode and an anode electrode associated with the same chamber. A capture detector detects for capture at both electrodes. If anodal capture is not detected, the energy of the pacing pulse is increased, until anodal capture is detected.

Method and apparatus with anodal capture monitoring

Techniques are provided for updating a morphology template used to discriminate abnormal cardiac rhythms. In one example, a non-weighted candidate morphology template is generated based on far-field R-wave morphology. A weighted candidate morphology template is generated based on an ensemble average of the non-weighted candidate morphology template and a previous (i.e. active) morphology template. The previous morphology template is then selectively updated based on a comparison of additional R-waves against both the non-weighted and the weighted candidate templates. Thereafter, abnormal cardiac rhythms such as ventricular tachycardia and supraventricular tachycardia are discriminated using the updated morphology template based on newly-detected far-field R-waves. These techniques provide a method for updating the morphology discrimination template in response to long-term changes in morphology due to cardiac remodeling or cardiac disease progression.

Systems and methods for selectively updating cardiac morphology discrimination templates for use with implantable medical devices

A system and method enables precise detection of the time of occurrence of a cardiac event of a heart. The method includes the steps of sensing electrical activity of the heart to generate an electrogram signal including the cardiac event, storing the electrogram signal, correlating the electrogram signal with an electrogram template, and identifying the time of occurrence of the cardiac event based upon the correlation.

System and method for accurately detecting cardiac events using retrospective correlation

Techniques are provided for use by implantable medical devices such as pacemakers or by external systems in communication with such devices. An intracardiac electrogram (IEGM) is sensed within a patient in which the device is implanted using a cardiac signal sensing system. Cardiac events of interest such as arrhythmias, premature atrial contractions (PACs), premature ventricular contractions (PVCs) and pacemaker mediated tachycardias (PMTs) are detected within the patient using event detection systems and then portions of the IEGM representative of the events of interest are recorded in device memory. Subsequently, during an off-line or background analysis, the recorded IEGM data is retrieved and analyzed to identify false detections. In response to false detections, the cardiac signal sensing systems and/or the event detection systems of the implantable device are selectively adjusted or reprogrammed to reduce or eliminate any further false detections, including false-positives or false-negatives. Various adaptive reprogramming techniques are described.

Systems and methods for off-line reprogramming of implantable medical device components to reduce false detections of cardiac events

A method for operating an implantable medical device includes delivering a plurality of pacing pulses to an atria of a patient's heart and monitoring intrinsic atrial activity to detect intrinsic atrial contractions between one or more of the plurality of pacing pulses. The method further includes detecting atrial undersensing as a function of the detection of intrinsic atrial contractions.

System and method for detecting and correcting atrial undersensing

A two-dimensional refractory period is defined in conjunction with the detection of cardiac events. Detection parameters associated with the two-dimensional refractory period may define a period of time during which a sensed cardiac signal is blanked or may define a period of time during which a given sensing threshold applies. The two-dimensional refractory period may be employed in atrial sensing to selectively blank far-field T-waves while enabling P-wave detection. The two-dimensional refractory period may be employed in ventricular sensing to selectively blank near-field T-waves while enabling detection of the QRS complex. The detection parameters associated with the two-dimensional refractory period may be adapted based on characteristics of previously detected cardiac signals.

Two-dimensional refractory period

Techniques for detecting tachyarrhythmia and also for preventing T-wave oversensing use signals filtered by a narrowband bradycardia filter in combination with signals filtered by a narrowband tachycardia filter. A separate wideband filter may also be used.

Systems and methods for employing multiple filters to detect T-wave oversensing and to improve tachyarrhythmia detection within an implantable medical device

Systems and methods are provided for use by an implantable medical device capable of automatically adjusting the sensitivity with which electrical cardiac signals are sensed within a patient, i.e. a device equipped with Automatic Sensitivity Control (ASC.) In a first example, ASC parameters are automatically adjusted by the device itself based on parameters derived from both R-waves and T-waves and further based on a detected noise floor. In a second example, a profile representative of the shape of cardiac signals is generated by the device. ASC parameters are then adjusted based on the profile. In various embodiments, histograms are used to determine sizes and shapes of the R-waves and T-waves via statistical prevalence techniques. The histograms are also employed to derive the aforementioned profile.

System and method for adjusting automatic sensitivity control parameters based on intracardiac electrogram signals

An implantable medical device includes a lead, a pulse generator, an autothreshold module and a control module. The lead includes electrodes positioned within a heart. At least one of the electrodes senses cardiac signals. The pulse generator delivers a stimulus pulse through at least one of the electrodes. The autothreshold module performs a threshold search when operating in an autothreshold mode and causes atrial stimulus pulses to be delivered in an atrium of the heart at an overdrive rate during the threshold search. The control module determines an AV conduction time and applies an overdrive AV adjustment to the AV conduction time to generate an AV delay. The autothreshold module uses the AV delay in connection with delivering ventricular stimulus pulses to a ventricle of the heart.

Method and system for overdriving a heart chamber during a threshold search according to an AV delay

An implantable medical device includes a first, short-range telemetry circuit; a second, long-range telemetry circuit; a first power system that powers the first telemetry circuit; and a second power system that powers the second telemetry circuit. The second power system includes an internal charging system and a rechargeable battery coupled to the internal charging system. The internal charging system may be configured for electromagnetic-inductive or RF-transmission coupling with an external charging system. A controller monitors the energy level of the rechargeable battery and provides an signal indicative of the level.

Medical devices and systems having separate power sources for enabling different telemetry systems

During a period of time comprising a plurality of cardiac cycles, a time relationship between ventricular events and atrial detections is established. Based on the relationship, a post-ventricular atrial refractory period is defined. The period includes an absolute atrial refractory period and a segmented relative atrial refractory period, wherein the segmented relative atrial refractory period includes at least one blanking window during which atrial detections of ventricular events have or are likely to occur.

Methods and devices involving automatic atrial blanking

Growing community of inventors

Chatsworth, CA, United States of America

Jeffery D Snell