Four-chamber pacing system for optimizing cardiac output and determining heart condition

• US 6,219,579 B1
• Filed: 01/28/2000
• Issued: 04/17/2001
• Est. Priority Date: 12/15/1997
• Status: Expired due to Fees

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Leinders, Robert, de Roos, Cobus, Bakels, Arnoldus
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US09/493,690
• Time in Patent Office: 445 Days
• Field of Search: 607/9, 607/11, 607/17, 607/24
• US Class Current: 607/17
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/36521 the parameter being derived from measurement of an electrical impedance
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/3682 with a variable atrioventricular delay

Abstract

A pacing system and method for providing multiple chamber pacing of a patient'"'"'s heart, and in particular, pacing programmed for treatment of various forms of heart failure. The system utilizes impedance sensing for determining optimum pacing parameters, e.g., for pacing the left ventricle so that left heart output is maximized. The impedance sensing also is used for determination of arrhythmias or progression of heart failure. Impedance sensing is provided for between selected pairs of the four chambers, to enable optimizing of information for control and diagnosis. In a preferred embodiment, impedance measurements are obtained for determining the timing of right heart valve closure or right ventricular contractions, and the timing of delivery of left ventricular pace pulses is adjusted so as to optimally synchronize left ventricular pacing with the right ventricular contractions. Impedance sensing in the left heart also provides timing of mechanical contraction, and the pacemaker controls pacing to maintain bi-ventricular mechanical synchronization adjusted for maximum cardiac output.

Claims

1. A system for bi-ventricular pacing, comprising;

RVP generating means for generating and delivering pacing pulses to the patient'"'"'s right ventricle;

LVP generating means for generating and delivering pacing pulses to the patient'"'"'s left ventricle;

atrial sense means for determining the cyclical time of excitation of the patient'"'"'s right and left atria;

RAVD control means for controlling said RVP generating means to deliver pace pulses at a predetermined RAVD delay following right atrial activation;

LAVD control means for controlling said LVP generating means to generate pace pulses at an LAVD delay following left atrial activation;

output means for determining a measure of cardiac output from the patient'"'"'s left ventricle;

adjusting means for adjusting said LAVD and RAVD delays and determining the optimum relationship of said LAVD and RAVD delays which results in maximized cardiac output;

program means for programming said RAVD control means and said LAVD control means to control delivery of pacing pulses to the left and right ventricles with said optimum relation.

2. The system as described in claim 1, comprising second adjusting means for adjusting said LAVD and RAVD equally, and wherein said output means obtains values of LAVD and RAVD corresponding to maximum cardiac output and

wherein said program means controls said RAVD control means and said LAVD control means to deliver pacing pulses with said values.

3. The system as described in claim 2, comprising means for obtaining the difference between LAVD and RAVD corresponding to optimized cardiac output, and means for maintaining said difference.