×

Intracardiac impedance and its applications

  • US 8,494,618 B2
  • Filed: 08/22/2005
  • Issued: 07/23/2013
  • Est. Priority Date: 08/22/2005
  • Status: Active Grant
First Claim
Patent Images

1. A system comprising:

  • a medical device including;

    a cardiac cycle sensing circuit, the sensing circuit configured to provide a sensed cardiac cycle;

    an impedance measurement circuit configured to provide an intracardiac impedance signal; and

    a controller circuit coupled to the impedance measurement circuit, the controller circuit configured to detect tachyarrhythmia from the intracardiac impedance signal using at least two of;

    a cardiac-cycle-to-cardiac-cycle change in a value of a baseline intracardiac impedance value calculated, for a particular cardiac cycle, to represent the baseline intracardiac impedance for that particular cardiac cycle;

    a cardiac-cycle-to-cardiac-cycle change in a value of maximum intracardiac impedance value calculated, for a particular cardiac cycle, to represent the maximum intracardiac impedance for that particular cardiac cycle; and

    a cardiac-cycle-to-cardiac-cycle change in a slope value of the intracardiac impedance waveform signal, for a particular cardiac cycle, the slope value measured at a time corresponding to one-half of a time interval over which a maximum intracardiac impedance change occurs during that particular cardiac cycle.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×