Methods for the Determination of T-Shock Vulnerable Window from Far-Field Electrograms in Implantable Cardioverter Defibrillators
AssigneesMedtronic, Inc., Imperception, Inc.
InventorsPaul A. Belk, Jian Cao, Jeffrey M. Gillberg, Charles D. Swerdlow
Life of this patent
Estimating the term…
Abstract
Methods for determination of timing for electrical shocks to the heart to determine shock strength necessary to defibrillate a fibrillating heart. The timing corresponds the window of most vulnerability in the heart, which occurs during the T-wave of a heartbeat. Using a derivatized T-wave representation, the timing of most vulnerability is determined by a center of the area method, peak amplitude method, width method, or other similar methods. Devices are similarly disclosed embodying the methods of the present disclosure.
Claims17
A method comprising:
- determining a t-wave window;
- obtaining a far-field signal;
- calculating a value for a most vulnerable moment (QTp) of the heart for each heartbeat;
- and
- determining a time value in which the heart is vulnerable to electric shocks.
A method comprising:
- obtaining a derivatized electrogram (EGM) of far-field data for a set of heartbeats for a heart;
- determining a T-window for each heart heartbeat;
- and
- determining a most vulnerable moment (QTp) of the heart for each heartbeat by calculating the center of the area of the derivatized EGM for the T-window.
An implantable medical device at least configured to:
- provide ventricular pacing pulses;
- and
- determine the a period of vulnerability wherein electrical shocks may be provided to defibrillate a fibrillating heart;
- wherein the implantable medical device is further configured to determine a period of vulnerability by:
- obtaining a derivatized electrogram (EGM) of far-field data for a set of heartbeats for a heart;
- determining a T-window for each heartbeat of the heart;
- and
- determining a most vulnerable moment (QTp) of the heart for each heartbeat.
Dependencies are inferred from the claim text.