Atrial aware VVI: a method for atrial synchronous ventricular (VDD/R) pacing using the subcutaneous electrode array and a standard pacing lead

• US 20020123769A1
• Filed: 12/14/2000
• Published: 09/05/2002
• Est. Priority Date: 12/14/2000
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Combs, William J., Panken, Eric J., Shelton, Michael B.
• Granted Patent: US 6,904,315 B2
• Time in Patent Office: Days
• US Class Current: 607/9
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence

Abstract

An algorithm is implemented in a circuit for sensing P-waves in a pacemaker to ensure ventricular pacing synchronization with sensed atrial depolarization waves. VDD and VDDR pacing (atrial synchronized, ventricular inhibited pacing) are implemented via a single standard ventricular pacing lead (unipolar or bipolar) and preferably a subcutaneous electrode array (SEA). Specifically, an implanted ventricular lead provides ventricular pacing and ventricular sensing while the SEA enable atrial sensing, thus eliminating the need for an implanted atrial lead or a specialized single pass VDD lead. The algorithm manages the sensed cardiac waves to effect a desired pacing regimen based on the input from the single lead and SEA.

Claims

1. A software implemented in a circuit for sensing p-waves in a pacemaker, the system in combination with the circuit comprising:

means for detecting atrial depolarization signals;

means for pacing the ventricle synchronous with said atrial depolarization signals; and

said means for detecting including subcutaneous electrodes in data communications with said means for pacing having at least one pacing lead.

2. The system of claim 1 wherein said means for pacing is a single chamber ventricular-inhibited pacemaker.

3. The system of claim 2 wherein said pacemaker includes a hermetically sealed case including said subcutaneous electrodes being peripherally distributed about the perimeter of the case.

4. The system of claim 2 wherein said pacemaker is coupled to a ventricular pacing lead.

5. The system of claim 4 wherein said pacing lead is one of unipolar and bipolar structure.

6. A sensing circuitry in co-operation with a pacer, a lead and a plurality of subcutaneous electrode arrays (SEA) implemented for pacing the ventricle synchronous with atrial depolarization signals, the circuitry comprising:

an analog-digital converter (ADC) for converting a plurality of signals,

a plurality of filters coupled to said ADC;

a detector for detecting at least one of said plurality of signals in communication with said plurality of filters;

a digital to analog converter (DAC) to convert signals passing through said detector; and

means for R-wave detection and means for p-wave detection coupled to said DAC.

7. The circuit of claim 6 wherein said plurality of signals include signal inputs into said ADC relating to ventricular electrogram (VEGM) from said lead, ECG data from said SEA and ECG data from an external lead.

8. The circuit of claim 7 wherein said VEGM is transmitted via a ventricular lead.

9. The circuit of claim 7 wherein said ECG data is transmitted from external electrodes such as from a programmer implemented to validate said ECG data from SEA.

10. The circuit of claim 7 wherein said VEGM signals include intrinsic ventricular depolarization waveforms that inhibit scheduled ventricular output pulse.

11. The circuit of claim 7 wherein said ECG data from the SEA is a primary input and provides ECG data to the ADC on a substantially continuous basis.

13. The sequencing method of claim 12 wherein said PVARP interval is used to blank retrograde p-waves thereby providing protection against pacemaker-mediated tachycardia (PMT).

14. The sequencing method of claim 12 wherein a VA interval is extended by an AV interval period and ventricular pacing pulse is emitted if no p-wave is sensed.

12. A software system implemented in a circuit to monitor underlying sequences that are used in single chamber ventricular-inhibited pacemaker, the sequencing method:

starting a PR cross check internal when a p-wave threshold crossing is sensed;

discounting a p-wave if an R-wave is detected in the PR cross check; and

triggering a PVARP interval when an R-wave is detected.