Pacemaker catheter utilizing bipolar electrodes spaced in accordance to the length of a heart depolarization signal

• US 5,127,403 A
• Filed: 08/21/1990
• Issued: 07/07/1992
• Est. Priority Date: 07/05/1988
• Status: Expired due to Fees

• Current Assignee: Cardiac Control System, Inc.
• Original Assignee: Cardiac Control System, Inc.
• Inventors: Brownlee, Robert R.
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): SCHAETZLE, KENNEDY
• Application Number:
  US07/570,540
• Time in Patent Office: 686 Days
• Field of Search: 128/783, 128/784, 128/786, 128/639, 128/642, 128/419 P, 128/419 PG, 128/696
• US Class Current: 607/122
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/0565 Electrode heads

Abstract

A catheter lead for a cardiac pacemaker in which stimulating pulses are generated for delivery to the heart according to physiological need of the patient determined by signals obtained solely from the detection of naturally occurring P-waves propagating through the atrial myocardial tissue.

Claims

1. A method for enhancing the detection of atrial P-waves using a catheter lead and a cardiac pacemaker in which stimulating pulses are generated for delivery to the heart according to physiological need of the patient determined by signals obtained solely from the detection of naturally occurring P-waves propagating through the artrial myocardial tissue, said method comprising

implanting a single catheter lead having a stimulating electrode at the distal end thereof and a pair of sensing electrodes thereon longitudinally spaced apart on opposite sides of the catheter from each other and from said distal end of the lead, by introducing the lead into the right atrial and ventricular chambers of the heart via the patient'"'"'s vascular system such that both of said sensing electrodes reside unrestrained within the right atrium with the lead substantially parallel to the tissue wall when the distal end of the lead is positioned at the apex of the right ventricle, measuring the approximate separation between adjacent positive and negative peaks of an average P-wave for the recipient and longitudinally spacing the sensing electrodes to approximate the separation between adjacent positive and negative peaks of the naturally occurring average atrial P-wave for the patient in which the lead is implanted,

connecting the lead at its proximal end to the pacemaker so that conductors in the lead separately electrically connected to said stimulating electrode and said pair of sensing electrodes are thereby electrically connected to the pulse generator and sense circuitry, respectively, of the pacemaker, and

additively combining in the sense circuitry of the pacemaker the respective signals on the separate conductors of the lead connected to each of said sensing electrodes resulting from detection of a P-wave, to enhance said P-wave detection.

2. A catheter for use in a cardiac pacemaker system, said catheter having only an electrode pair arrangement limited to two electrodes operating together in a bipolar configuration for sensing cardiac depolarization signals without requiring contact with cardiac tissue,

said electrode pair axially configured on the catheter relative to the cardiac depolarization wavefront direction, to prevent signal cancellation and excess signal mitigation when the signals sensed from each electrode of the pair are electronically processed by the pacemaker system,

said electrode pair is further configured such that the electrodes are placed on opposite sides relative to the catheter'"'"'s, longitudinal axis and displaced longitudinal along the axis of the catheter and substantially parallel to the axis of depolarization to provide for control of the electrode dimensions in three planes to minimize field averaging in said planes and prevent signal cancellation as the depolarization wave passes each electrode.

3. A method for sensing cardiac depolarization in a cardiac pacemaker system comprising the steps, arranging an electrode pair of only two electrodes axially on a catheter, operating said electrode pair in a bipolar configuration, determining the cardiac depolarization signal length while the electrode pair is not in contact with cardiac tissue, configuring the electrode pair on the catheter relative to the cardiac depolarization signal wavefront direction to prevent signal cancellation or signal mitigation when the signals sensed from each of the pair of electrodes are electronically processed by the pacemaker system, configuring the electrode pair on opposite sides of the catheter and displaced longitudinally a distance equal to the length of the depolarization signal along the axis of the catheter substantially parallel to the axis of depolarization, such that the combinational features of controlling the electrode dimensions in each of three planes to minimize field averaging in all planes prevents signal cancellation as the depolarization wave passes each electrode.

4. The method, as defined in claim 3, further including the step of placing the electrode pair in a blood pool.