Activity-responsive pacer with bipolar sensor electrode
First Claim
1. A pacemaker system comprising:
- an electrode lead having only a distal tip electrode for supplying stimulation pulses to heart tissue and, proximal to said distal tip electrode, a ring electrode;
a cardiac stimulator, which emits stimulation pulses having a stimulation parameter associated therewith, to which said electrode lead is electrically connected;
detector means for detecting electrical cardiac activity between said tip electrode and said ring electrode;
means for applying a measuring parameter on said ring electrode during a predetermined measuring period and for measuring a measurement value through said ring electrode during at least a part of said period for sensing, via said ring electrode, at least one physical activity-dependent parameter;
means for adjusting said stimulation parameter dependent on said measured value.
1 Assignment
0 Petitions
Accused Products
Abstract
A pacemaker system includes an electrode lead having a distal tip electrode for supplying stimulation pulses to cardiac tissue and a ring electrode, the electrode lead being connected to a cardiac stimulator. A detector is contained in a stimulator housing and is connected to the electrode lead for detecting electrical cardiac activity between said ring electrode and said tip electrode. Measurement of a signal dependent on physical activity of the subject in whom the pacemaker is implanted is obtained either by applying a voltage on the ring electrode during a predetermined measuring period and measuring a current through the ring electrode during at least a part of this period, or by, after detection of a QRS wave, applying a potential on the ring electrode and measuring the current between the housing and the ring electrode during the measuring period and also applying an alternating current between the tip electrode and the housing and measuring a voltage difference between the tip electrode and the ring electrode. The stimulation rate is then adjusted dependent on the measured value or values obtained.
17 Citations
21 Claims
-
1. A pacemaker system comprising:
-
an electrode lead having only a distal tip electrode for supplying stimulation pulses to heart tissue and, proximal to said distal tip electrode, a ring electrode; a cardiac stimulator, which emits stimulation pulses having a stimulation parameter associated therewith, to which said electrode lead is electrically connected; detector means for detecting electrical cardiac activity between said tip electrode and said ring electrode; means for applying a measuring parameter on said ring electrode during a predetermined measuring period and for measuring a measurement value through said ring electrode during at least a part of said period for sensing, via said ring electrode, at least one physical activity-dependent parameter; means for adjusting said stimulation parameter dependent on said measured value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A system for controlling a stimulation frequency of a cardiac pacemaker dependent on physical activity, said pacemaker adapted for implantation in a human body and having a cardiac stimulator in said housing which emits stimulation pulses at said rate, and a connector housing having a reference electrode on an exterior thereof, said system comprising:
-
a bipolar lead having a distal tip electrode adapted for implantation in a ventricle and a ring electrode disposed a distance from said tip electrode in a range from 6-15 cm; means in said housing for detecting a potential difference between said tip electrode and said ring electrode; means in said housing for applying, after detection of a QRS wave by said means for detecting, a physiological parameter measuring potential on said ring electrode, relative to said reference electrode, for a predetermined measuring time; means in said housing for measuring a current between said housing and said ring electrode during at least a portion of said measuring time; and means for triggering said cardiac stimulator to emit pacing pulses between said pacemaker housing and said tip electrode at a rate dependent on said current. - View Dependent Claims (16)
-
-
17. A system for controlling a stimulation frequency of a cardiac pacemaker dependent on physical activity, said pacemaker adapted for implantation in a human body and having a cardiac stimulator in said housing which emits stimulation pulses at said rate, and a connector housing having a reference electrode on an exterior thereof, said system comprising:
-
a bipolar lead having a distal tip electrode adapted for implantation in a ventricle, and a ring electrode proximal to said tip electrode; means in said housing for detecting a potential difference between said tip electrode and said ring electrode; means for applying, after detection of a QRS wave by said means for detecting, a physiological parameter measuring potential on said ring electrode, relative to said reference electrode, for a predetermined measuring time; means for measuring a current between said housing and said ring electrode during at least a portion of said measuring time; means for supplying an alternating current between said tip electrode and said housing; means for measuring a voltage difference between said tip electrode and said ring electrode; and means for triggering emission of stimulation pulses by said cardiac stimulator between said housing and said tip electrode at a rate dependent on both the current measured between said housing and said ring electrode and the voltage difference measured between said tip electrode and said ring electrode. - View Dependent Claims (18, 19, 20, 21)
-
Specification