MEDICAL TELEMETRY SYSTEM AND OPERATING METHOD THEREFOR

• US 20090177250A1
• Filed: 06/09/2006
• Published: 07/09/2009
• Est. Priority Date: 06/09/2006
• Status: Active Grant

• Current Assignee: St. Jude Medical AB (Abbott Laboratories Incorporated)
• Original Assignee: St. Jude Medical AB (Abbott Laboratories Incorporated)
• Inventors: Abrahamson, Hans
• Granted Patent: US 8,060,213 B2
• Time in Patent Office: Days
• US Class Current: 607/60
• CPC Class Codes: A61N 1/37254 Pacemaker or defibrillator security, e.g. to prevent or inhibit programming alterations by hackers or unauthorised individuals
• CPC Class Codes: A61N 1/37282 characterised by communication with experts in remote locations using a network
• CPC Class Codes: H04W 76/10 Connection setup

Abstract

A method in a telemetry system for establishing a connection between a base station and an implantable medical device includes the steps of: starting, in the base station, a first timer B-T₂; determining, in the base station 4, channels that are free for communication among a number of available channels, and selecting one of the free channels; starting, in the base station, a second timer; transmitting, as long as the first or second timer has not expired, a recognition message on the selected channel to the implantable medical device; and establishing, upon receipt of a recognition reply message from the implantable medical device, communication between the base station and the implantable medical device on the selected channel. The invention is readily adaptable for fulfillment of different requirements, such as stipulated by the ETSI standard.

Claims

1. Method in a telemetry system for establishing communication between an implantable medical device and a base station of said telemetry system, comprising the steps of:

starting, in said base station, a first timer,

determining, in said base station, channels that are free for communication among a number of available channels, and selecting one of said free channels;

starting, in said base station, a second timer, upon selecting said one of said free channels;

transmitting, as long as said first timer or second timer has not expired, a recognition message on the selected channel to the implantable medical device, and

establishing, upon receipt of a recognition reply message from said implantable medical device, communication between said base station and said implantable medical device on said selected channel.

2. The method as claimed in claim 1, further comprising the step of repeating, if said second timer has expired while said first timer has not expired and if no recognition reply message is received from said implantable medical device, the steps of:

determining and selecting a free channel, starting the second timer and transmitting a recognition message to the implantable medical device.

3. The method as claimed in claim 1, wherein the step of determining and selecting a free channel comprises the sub-steps of:

measuring received signal strengths of said free channels; and

selecting the channel having the lowest signal strength.

4. The method as claimed in claim 1, comprising employing a dedicated implantable medical device as said implantable medical device.

5. The method as claimed in claim 1, comprising setting said first timer to a time interval within a range of 5-60 seconds.

6. The method as claimed in claim 5, comprising setting said second timer to a time interval within a range of 1-5 seconds.

7. The method as claimed in claim 1, comprising initiating said method an occurrence of an activating mechanism.

8. The method as claimed in claim 7, comprising employing a timer indicating a time of day as said activating mechanism.

9. The method as claimed in claim 1, comprising halting said method if said second timer expires.

10. The method as claimed in claim 9, comprising causing said base station to repeat said steps after a specified period of time.

11. Method in a telemetry system for allocating a channel for use in communication between an implantable medical device and a base station of said telemetry system, comprising performing, in said implantable medical device, the steps of:

starting a first timer;

listening for signals transmitted from said base station and determining, among a number of channels, channels that are free for communication;

setting a channel number to Ch=First−

1, wherein First is the lowest channel number of said free channels;

starting a second timer;

selecting channel Ch=Ch+1 among the available N channels, wherein if Ch≧

First+N, then setting Ch=First;

listening on said selected channel as long as said first timer or second timer has not expired and as long as no recognition message has been received;

repeating, as long as said first timer has not expired and no recognition message is received from said base station and said second timer has expired, said steps of;

starting the second timer, selecting the channel among the available N channels and listening on said selected channel; and

transmitting, upon receipt of a recognition message from said base station, a recognition reply message to said base station.

12. The method as claimed in claim 11, comprising employing a dedicated implantable medical device as said implantable medical device.

13. The method as claimed in claim 11, comprising said first timer to a time interval within a range of 10-60 seconds.

14. The method as claimed in claim 11, comprising setting said second timer to a time interval within a range of 10-100 ms.

15. The method as claimed in claim 11 said method if said second timer expires.

16. The method as claimed in claim 15, comprising repeating all steps after a specified period of time.

17. The method as claimed in claim 11 comprising initiating said method upon an occurrence of an activating mechanism.

18. The method as claimed in claim 17, comprising employing an external activating mechanism as said activating mechanism.

19. The method as claimed in claim 18, wherein comprising selecting said external activating mechanism from the group consisting of a magnet, inductive loop telemetry, and other radio alert system.

20-21. -21. (canceled)

22. A base station for a telemetry system that includes an implantable medical device in addition to the base station, said base station comprising:

a first timer, a second timer, a processor, and a transmitter configured to communicate with said implantable medical device, and a reception unit; and

said processor being configured to start said first timer upon an occurrence of an activating mechanism and thereafter to determine communication channels, among a number of available communication channels, that are free for communication with said implantable medical device, and to select one of said free channels, and thereafter to start said second timer, and to cause said transmitter to transmit, as long as said first timer or said second timer has not expired, a recognition message on the selected one of said free channels to said implantable medical device and to establish, upon receipt by said reception unit of a recognition reply message from said implantable medical device, communication between said implantable medical device and said base station on said selected one of said free channels.

23. A base station for a telemetry system that includes a base station in addition to the implantable medical device, said implantable medical device comprising:

a first timer, a second timer, a processor, and a transmitter configured to communicate with said base station, and a reception unit; and

said processor being configured to start said first timer upon an occurrence of an activating mechanism and thereafter to determine communication channels, among a number of available communication channels, that are free for communication with said base station, and to select one of said free channels, and thereafter to start said second timer, and to cause said transmitter to transmit, as long as said first timer or said second timer has not expired, a recognition message on the selected one of said free channels to said base station and to establish, upon receipt by said reception unit of a recognition reply message from said base station, communication between said base station and said base station on said selected one of said free channels.