US 8,577,449 B2 · Method and system for ischemia detection

Abstract

Disclosed are systems and methods for automatically determining ST windows for ischemia detection. An IEGM signal is obtained over a period of time a derivative signal of the IEGM signal is calculated. The R-wave is identified in the derivative signal and the derivative signal data following the identified R-wave is analyzed to find portions of the derivative signal comprising samples having lower values than a predetermined threshold. Further, a portion of the derivative signal including samples having lower values than the threshold is determined to correspond to a ST window for that cardiac cycle if that portion fulfills predetermined requirements. A reference ST window based on a number of determined ST windows is determined. Using the reference ST window, ischemia can be detected by comparing IEGM data in the reference ST window with current IEGM data from a segment of the IEGM signal corresponding to the reference ST window.

Claims16

Dependent claims

A method for ischemia detection comprising:

obtaining at least one IEGM signal representative of cardiac behavior of a patient over a period of time;
calculating a derivative signal of the IEGM signal;
identifying a R-wave in the derivative signal or in the IEGM signal;
analyzing said derivative signal data following said identified R-wave so as to find portions of said derivative signal comprising samples having lower values than a predetermined threshold;
determining a portion of said derivative signal including samples having lower values than said threshold to correspond to a ST window for that cardiac cycle if that portion fulfills predetermined requirements;
creating a reference ST window based on a number of said determined ST windows;
and
detecting ischemia by comparing IEGM data in said reference ST window with current IEGM data from a segment of the IEGM signal corresponding to the reference ST window.

5 more elements

A system for ischemia detection comprising:

a data collection module configured to obtain at least one IEGM signal indicating cardiac behavior of a cardiac cycle corresponding a heartbeat;
a data processing module configured to calculate a derivative signal of the IEGM signal;
a detector configured to identify a R-wave in the derivative signal or in the IEGM signal
an ST window determining module configured to:
analyze said derivative signal data following said identified R-wave so as to find portions of said derivative signal comprising samples having lower values than a predetermined threshold;
determine a portion of said derivative signal including samples having lower values than said threshold to correspond to a ST window for that cardiac cycle if that portion fulfills predetermined requirements;
and
create a reference ST window based on a number of said determined ST windows;
and
an ischemia detection module configured to detect ischemia by comparing IEGM data in said reference ST window with current IEGM data from a segment of the IEGM signal corresponding to the reference ST window.

7 more elements

Dependencies are inferred from the claim text.

Method and system for ischemia detection

Life of this patent

Method and system for ischemia detection

Life of this patent

Abstract

Claims16