Tiered therapy cardiac detection system having a global counter
First Claim
1. A medical device having tiered therapy cardiac detection system, the medical device comprising:
- the detection system comprising;
a sensing system that senses cardiac signals representative of beat-to-beat intervals;
a therapy delivery system that delivers at least one therapy in response to a detected cardiac dysrhythmia corresponding to one of a plurality of programmed zones of heart rates; and
a tiered therapy cardiac detection system, includinga global counter that counts at least all beat-to-beat intervals indicating a rate greater than a programmed threshold value which is representative of a minimum heart rate for delivering any therapy once a predetermined initial threshold condition has been met;
a plurality of window memories, each window memory corresponding to a given one of the plurality of zones and storing at least an indication of whether each of a last N cardiac signals are within that programmed zone of heart rates;
a plurality of parameter memories, each parameter memory corresponding to a given one of the plurality of zones and storing a programmed trigger value of the global counter required in order for a therapy in that zone to be delivered; and
processing circuitry that determines whether the predetermined initial threshold condition has been met and, in response, evaluates the global counter, the window memories and the parameter memories on a beat-by-beat basis and indicates that a cardiac dysrhythmia has been detected for a given zone if the global counter exceeds the programmed trigger value for that zone and the indications stored by the window memory for that zone satisfy predetermined criteria.
1 Assignment
0 Petitions
Accused Products
Abstract
A tiered therapy cardiac detection system is provided for a medical device that senses cardiac signals representative of beat-to-beat intervals and delivers at least one therapy in response to a detected cardiac dysrhythmia corresponding to one of a plurality of programmed zones of heart rates. The detection system includes a global counter that counts at least all beat-to-beat intervals indicating a rate greater than a programmed threshold value representative of a minimum heart rate for delivering any therapy once an initial threshold condition is met. A plurality of window memories and parameter memories are provided in the device. Each window memory corresponds to a given one of the zones and stores an indication of whether each of a last N cardiac signals are within that zone. Each parameter memory corresponds to a given one of the zones and stores a programmed trigger value of the global counter required in order for a therapy in that zone to be delivered. Processing circuitry evaluates the global counter, the window memories and the parameter memories on a beat-by-beat basis and indicates that a cardiac dysrhythmia has been detected for a given zone if the global counter exceeds the programmed trigger value for that zone and the indications stored by the window memory for that zone satisfy a predetermined criteria.
18 Citations
26 Claims
-
1. A medical device having tiered therapy cardiac detection system, the medical device comprising:
- the detection system comprising;
a sensing system that senses cardiac signals representative of beat-to-beat intervals; a therapy delivery system that delivers at least one therapy in response to a detected cardiac dysrhythmia corresponding to one of a plurality of programmed zones of heart rates; and a tiered therapy cardiac detection system, including a global counter that counts at least all beat-to-beat intervals indicating a rate greater than a programmed threshold value which is representative of a minimum heart rate for delivering any therapy once a predetermined initial threshold condition has been met; a plurality of window memories, each window memory corresponding to a given one of the plurality of zones and storing at least an indication of whether each of a last N cardiac signals are within that programmed zone of heart rates; a plurality of parameter memories, each parameter memory corresponding to a given one of the plurality of zones and storing a programmed trigger value of the global counter required in order for a therapy in that zone to be delivered; and processing circuitry that determines whether the predetermined initial threshold condition has been met and, in response, evaluates the global counter, the window memories and the parameter memories on a beat-by-beat basis and indicates that a cardiac dysrhythmia has been detected for a given zone if the global counter exceeds the programmed trigger value for that zone and the indications stored by the window memory for that zone satisfy predetermined criteria. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
- the detection system comprising;
-
15. A method of implementing a tiered therapy cardiac detection system for a medical device that includes a sensing system that senses cardiac signals representative of beat-to-beat intervals, a therapy delivery system that delivers at least one therapy in response to a detected cardiac dysrhythmia corresponding to one of a plurality of programmed zones of heart rates, and a processor system and associated memory that process the cardiac signals to determine when a cardiac dysrhythmia is detected, the method comprising the processor implemented steps of:
-
(a) programming in the associated memory a threshold value which is representative of a minimum heart rate for delivering any therapy; (b) defining in the associated memory a plurality of parameter memories, each parameter memory corresponding to a given one of the plurality of zones, and programming a trigger value in terms of a number of cardiac signals required in order for a therapy in that zone to be delivered; (c) defining in the associated memory a plurality of window memories, each window memory corresponding to a given one of the plurality of zones; (d) if aa predetermined initial threshold condition is met, on a beat-by-beat basis; (d1) counting as a global counter at least all subsequent beat-to-beat intervals indicating a rate greater than the threshold value; (d2) storing at least an indication of whether each of a last N cardiac signals are within that programmed zone of heart rates; and (d3) evaluating the global counter, the window memories and the parameter memories and indicating that a cardiac dysrhythmia has been detected for a given zone if the global counter exceeds the programmed trigger value for that zone and the indications stored by the window memory for that zone satisfy predetermined criteria. - View Dependent Claims (16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
-
Specification