IMPLANTABLE DEVICE AND METHOD FOR MONITORING VENOUS DIAMETER

• US 20150051467A1
• Filed: 08/25/2014
• Published: 02/19/2015
• Est. Priority Date: 04/25/2008
• Status: Abandoned Application

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Corbucci, Giorgio, Van Der Veen, Johannes S., Van Lembergen, Geert, Verschelling, Marinus C.J., Smit, Josephus P.A.
• Application Number:
  US14/467,473
• Publication Number:
  US 20150051467A1
• Time in Patent Office: Days
• US Class Current: 600/381
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/02152 specially adapted for venous pressure
• CPC Class Codes: A61B 5/02158 provided with two or more sensor elements
• CPC Class Codes: A61B 5/0538 invasively, e.g. using a catheter
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/1076 for measuring dimensions inside body cavities, e.g. using catheters A61B3/1005 takes precedence
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61B 8/0891 for diagnosis of blood vessels
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00

Abstract

An implantable medical device system and associated method receive a signal from an implantable sensor operatively positioned relative to a vein, the signal being responsive to changes in a diameter of the vein. A diameter of the vein is determined in response to the sensor signal and used in estimating central venous pressure (CVP).

Claims

1. A method for use in an implantable medical device, comprising:

receiving a signal from an implantable sensor operatively positioned relative to a vein, the signal being responsive to changes in a diameter of the vein;

determining a diameter of the vein in response to the sensor signal; and

estimating a central venous pressure (CVP) based upon the vein diameter.

2. The method of claim 1 wherein the implantable sensor comprising at least a pair of measurement electrodes.

3. The method of claim 1 wherein the sensor comprises an electrode and the sensor signal comprises an impedance signal.

4. The method of claim 1 wherein the sensor comprises an ultrasound transducer and the signal comprises an ultrasound signal.

5. The method of claim 1 wherein the sensor comprises a first electrode, a second electrode and a third electrode positioned along a preformed portion of a medical lead body, wherein the sensor signal comprises a voltage signal, and wherein determining the vein diameter comprises:

applying an electrical pulse between the first electrode and the second electrode in a driver electrode pair;

measuring the voltage signal between the second electrode and the third electrode in a measurement electrode pair;

computing the vein diameter in response to the measured voltage signal; and

the preformed portion changing shape with a change in vein diameter and causing a distance between one of the driver electrode pair and the measuring electrode pair to change in response to the shape change of the preformed portion.

6. The method of claim 5 wherein the first, second and third electrodes being triangulated.

7. The method of claim 1 wherein determining the vein diameter comprises determining a change in vein diameter corresponding to a respiratory cycle.

8. The method of claim 7 further comprising sensing a signal responsive to respiration for detecting the respiratory cycle.

9. The method of claim 7 further comprising detecting congestive heart failure in response to a change in vein diameter corresponding to the respiratory cycle being absent.

10. The method of claim 7 wherein estimating the central venous pressure comprises determining a trend in the change in vein diameter corresponding to a respiratory cycle.

11. The method of claim 10 further comprising determining a respiration rate and wherein the trend in the change in vein diameter corresponding to a respiratory cycle compares the respiration rate to the change in vein diameter.

12. The method of claim 1 further comprising determining a trend in the estimated CVP.

13. The method of claim 12 further comprising detecting a worsening heart failure condition in response to the estimated central venous pressure and the trend in the estimated CVP.

14. An implantable medical device, comprising:

processing means for receiving a signal from an implantable sensor operatively positioned relative to a vein, the signal being responsive to changes in a diameter of the vein;

processing means for determining a diameter of the vein in response to the sensor signal; and

processing means for estimating a central venous pressure (CVP) based upon the vein diameter, wherein the implantable sensor comprising at least a pair of measurement electrodes.

15. A method for use in an implantable medical device, comprising:

receiving a signal from an implantable sensor operatively positioned relative to a vein, the signal being responsive to changes in a diameter of the vein;

determining a diameter of the vein in response to the sensor signal;

estimating a central venous pressure (CVP) based upon the vein diameter;

wherein the sensor comprises a first electrode, a second electrode and a third electrode positioned along a preformed portion of a medical lead body, wherein the sensor signal comprises a voltage signal, and wherein determining the vein diameter comprises;

applying an electrical pulse between the first electrode and the second electrode in a driver electrode pair;

measuring the voltage signal between the second electrode and the third electrode in a measurement electrode pair;

computing the vein diameter in response to the measured voltage signal; and

the preformed portion changing shape with a change in vein diameter and causing a distance between one of the driver electrode pair and the measuring electrode pair to change in response to the shape change of the preformed portion.