Pacesetter, Inc.

Mohssen Fard

Gene A Bornzin

Jong Gill

Peter Boileau

Joseph J Florio

Xiaoyi Min

Jeffery D Snell

Jay Snell

Bing Zhu

Gregory Hauck

Laleh Jalali

Josh Reiss

Elia Arambula Mouchawar

Bonian Dai

Corey L Brown

Zifei Wang

An implanted cardiac rhythm management device is disclosed that is operative to detect myocardial ischemia. This is done by evaluating electrogram features to detect an electrocardiographic change; specifically, changes in electrogram segment during the early part of an ST segment. The early part of the ST segment is chosen to avoid the T-wave.

Ischemia detection using intra-cardiac signals

Techniques are described for efficiently detecting and distinguishing among cardiac ischemia, hypoglycemia or hyperglycemia based on intracardiac electrogram (IEGM) signals. In one example, a preliminary indication of an episode of cardiac ischemia is detected based on shifts in ST segment elevation within the IEGM. In response, the implanted device then records additional IEGM data for transmission to an external system. The external system analyzes the additional IEGM data to confirm the detection of cardiac ischemia using a more sophisticated analysis procedure exploiting additional detection parameters. In particular, the external system uses detection parameters capable of distinguishing hypoglycemia, hyperglycemia and hyperkalemia from cardiac ischemia, such as QTmax and QTend intervals. Alternatively, the more sophisticated analysis procedure may be performed by the device itself, if it is so equipped. Other examples described herein pertain instead to the detection of atrial fibrillation.

System and method for efficiently distinguishing among cardiac ischemia, hypoglycemia and hyperglycemia using an implantable medical device and an external system

A technique is provided for detecting episodes of cardiac ischemia based on an examination of post-T-wave signal segments. Since cardiac ischemia is often a precursor to acute myocardial infarction (AMI) or ventricular fibrillation (VF), the technique thereby provides a method for predicting the possible onset of AMI or VF so that a warning may be delivered to the patient. The warning preferably includes both a perceptible electrical notification signal applied directly to subcutaneous tissue and a warning signal delivered via short range telemetry to a handheld warning device external to the patient. In one example, the onset of cardiac ischemia is identified by detecting a sharp falling edge within post-T-wave signals by filtering the signals using a high-pass filter having a cutoff frequency of at least 1 Hz. The total amount of energy in the filtered signal is calculated and compared against various thresholds.

System and method for detecting cardiac ischemia using an implantable medical device

An implantable cardiac stimulation device and associated method capable of delivering non-invasive programmed stimulation for electrophysiological testing in which the onset of the non-invasive programmed stimulation is triggered by a cardiac event, either a detected intrinsic event or a stimulated event, occurring in the heart chamber to be tested. When a non-invasive programmed stimulation command is received by the implanted device, it switches to a routine that allows transition to a non-invasive programmed stimulation from a standard operating mode, during a refractory period. The stimulation device also provides a recovery delay following the last pulse of a non-invasive programmed stimulation sequence. If no intrinsic activity is detected during the recovery delay, a refractory period is started following the expiration of the recovery delay. During this refractory period, a transition from the non-invasive programmed stimulation state machine back to the standard stimulation state machine is accomplished.

Method and apparatus for electrophysiological testing in an implantable device

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Woodland Hills, CA, United States of America

Mohssen Fard