System and method for pacing rate control utilizing patient hemodynamic status information

• US 8,417,336 B2
• Filed: 05/26/2010
• Issued: 04/09/2013
• Est. Priority Date: 06/01/2009
• Status: Expired due to Fees

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Maskara, Barun, Liu, Lili, Alvarez, Guy, Meyer, Scott A.
• Primary Examiner(s): DIETRICH, JOSEPH M
• Application Number:
  US12/787,868
• Publication Number:
  US 20100305650A1
• Time in Patent Office: 1,049 Days
• Field of Search: 607/9, 607/11, 607/17
• US Class Current: 607/9
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/36564 controlled by blood pressure
• CPC Class Codes: A61N 1/36585 controlled by two or more physical parameters

Abstract

A system and method for pacing rate control in a cardiac rhythm management (CRM) system. The method includes acquiring a pressure signal representative of coronary venous pressure (CVP) from a pressure sensor implanted within a coronary vein of the patient and generating a CVP waveform from the pressure signal. A pacing stimulus is applied to the patient'"'"'s heart, and the pacing rate is increased in response to increases in patient'"'"'s metabolic demand. The CVP index is monitored during the pacing rate increase, and the CRM system detects a reduction in the patient'"'"'s hemodynamic performance based on the CVP index and establishes a maximum rate setting based on the pacing rate corresponding to the reduction in the patient'"'"'s hemodynamic performance.

Claims

1. A method of operating an implanted rate adaptive cardiac rhythm management system in a patient, the method comprising:

acquiring a pressure signal representative of coronary venous pressure (CVP) from a pressure sensor implanted within the lower apical two thirds of a coronary vein of the patient and generating a CVP waveform therefrom;

applying a pacing stimulus to the patient'"'"'s heart, the pacing stimulus defined by a set of pacing parameters including a pacing rate;

acquiring a signal representative of the patient'"'"'s metabolic demand from at least one implanted sensor;

monitoring a CVP index derived from the CVP waveform while increasing the pacing rate in response to an increase in the patient'"'"'s metabolic demand, wherein the CVP index is based on coronary venous pulse pressure (CV-PP) sensed by the pressure sensor;

detecting a reduction in the patient'"'"'s hemodymanic performance based on the CVP index resulting from increasing the pacing rate; and

establishing a maximum rate setting based on the pacing rate corresponding to the reduction in the patient'"'"'s hemodynamic performance, wherein the maximum rate setting delimits further metabolic demand-induced pacing rate increases.

2. The method of claim 1 wherein establishing the maximum rate setting includes defining the maximum rate setting as a pacing rate above which any further increase in pacing rate leads to the reduction in the patient'"'"'s hemodynamic performance.

3. The method of claim 1 wherein establishing the maximum rate setting includes defining the maximum rate setting as a pacing rate below, by a predetermined amount, a pacing rate above which any further increase in pacing rate leads to the reduction in the patient'"'"'s hemodynamic performance.

4. The method of claim 1 wherein the predetermined amount is a predetermined number of beats per minute or a predetermined percentage.

5. The method of claim 1 wherein monitoring the CVP index includes generating a waveform of average CV-PP values as a function of the pacing rate during a period in which the pacing rate is increased in response to increased metabolic demand.

6. The method of claim 5 wherein detecting the reduction in the patient'"'"'s hemodymanic performance includes detecting a reduction in the patient'"'"'s average CV-PP during the period in which the pacing rate is increased in response to increased metabolic demand.

7. The method of claim 6 wherein establishing the maximum rate setting includes establishing the maximum rate setting based on the pacing rate corresponding to the reduction in the patient'"'"'s average CV-PP value.

8. The method of claim 1 wherein the CVP index is a change in a CV-PP, and wherein detecting the reduction in the patient'"'"'s hemodymanic performance includes identifying a decrease in the CV-PP accompanying the increase in the pacing rate in response to a metabolic demand increase.

9. The method of claim 1 wherein the maximum rate setting is a maximum sensor rate (MSR) or maximum tracking rate (MTR).

10. A method of operating an implanted cardiac rhythm management system in a patient, the method comprising:

acquiring a pressure signal indicative of coronary venous pressure (CVP) from a pressure sensor implanted within the lower apical two thirds of a coronary vein of the patient and deriving a selected CVP index from the pressure signal;

calculating a baseline CVP index value based on the pressure signal, the CVP index based on coronary venous end diastolic pressure (CV-EDP) of the CVP;

applying a pacing stimulus to the patient'"'"'s heart, the pacing stimulus defined by a set of pacing parameters including a maximum rate setting;

acquiring a signal representative of the patient'"'"'s metabolic demand from at least one implanted sensor;

responsive to an increase in the patient'"'"'s metabolic demand, increasing the pacing rate and the maximum rate setting while monitoring the CVP index; and

detecting a reduction in the patient'"'"'s hemodymanic performance based on a change, relative to the CVP index baseline value, in the CVP index resulting from increasing the pacing rate, wherein the change comprises an increase in the slope of the CV-EDP; and

maintaining the maximum rate setting at a pacing rate below the pacing rate corresponding to the detected reduction in the patient'"'"'s hemodynamic performance.

11. The method of claim 10 wherein the baseline CVP index value is derived prior to the pacing rate increase in response to the increase in the patient'"'"'s metabolic demand.

12. The method of claim 11 wherein the CVP index is a rolling average CV-EDP value during a period in which the pacing rate is increased in response to the increase in the patient'"'"'s metabolic demand.

13. An implantable rate adaptive cardiac rhythm management system configured for applying pacing stimuli to a patient'"'"'s heart, the pacing stimuli defined by pacing parameters including a pacing rate and a maximum rate setting, the system comprising:

a plurality of implantable medical electrical leads configured to sense cardiac electrical activity and to deliver the pacing stimuli, at least one of the leads being configured for chronic implantation within a coronary vein of the patient'"'"'s heart and including a pressure sensor configured to generate a coronary venous pressure (CVP) signal indicative of fluid pressure from within the lower apical two thirds of a coronary vein;

an implantable pulse generator operatively coupled to the leads configured to generate the pacing stimuli, the pulse generator including a control system configured to;

generate a CVP waveform based on the pressure signal and derive a CVP index therefrom, wherein the CVP index is based on coronary venous pulse pressure (CV-PP) sensed by the pressure sensor;

detect reductions in the patient'"'"'s hemodynamic performance based on the CVP index caused by an increase in the pacing rate; and

adaptively adjust the pacing rate and the maximum rate setting in response to changes in the patient'"'"'s metabolic demand,

wherein during use, the maximum rate setting is selectively defined by the control system based on the pacing rate corresponding to the identified reduction in the patient'"'"'s hemodynamic performance.