Recorder with patient alarm and service request systems for use with automatic implantable defibrillator

Claim 2

For use with biomedical apparatus operable, in response to the occurrence of a preselected physiological event characterizing a condition in a particular physiological function requiring corrective action, to initiate said corrective action automatically, a recorder system responsive to a physiological signal indicative of said particular physiological function, said recorder system comprising: first storage means for providing a continuously updated storage of said physiological signal prior to operation of said biomedical apparatus, second storage means responsive to the operation of said biomedical apparatus for providing a storage of said physiological signal during and after operation of said biomedical apparatus, and comma-ndable means for reading out the data storage provided by each of said first and second storage means. 25

Claim 3

The recorder system specified in claim 1 wherein said biomedical apparatus is an automatic defibrillator rendered operable upon the occurrence of abnormal cardiac activity to apply one or more defibrillation electrical impulses to the patient's heart intended to return the patient's heart to normal functioning and wherein said recorder system is responsive to the patient's electrocardiagram (ECG) signal.

Claim 4

The recorder system specified in claim 2 wherein said recorder system comprises: means for converting the patient's analog electrocardiagram (ECG) signal into a succession of corresponding digital data words, and memory means subdivided into a first portion updated continuously to store the digital code words corresponding to a preselected first ECG interval prior to the operation of said defibrillator, and a second portion to store the digital code words corresponding to a second preselected ECG interval encompassing the operation of said defibrillator and indicating the patient's response to said defibrillation electrical impulse(s).

Claim 5

The recorder system specified in claim 2 further including means rendered effective upon the occurrence of said abnormal cardiac activity to 115 provide a first alarm warning signal to the patient indicating said occurrence and rendered effective following operation of said automatic defibrillator to provide a second service request warning signal to the patient indicating that said automatic defibrillator has operated.

Claim 6

The recorder system specified in claim 4 wherein said first and second warning signals are distinguishable from one another by the patient. 60

Claim 7

The recorder system specified in claim 5 wherein said second warning signal is repeated at selected intervals for continuously reminding the patient to seek medical assistance.

Claim 8

The recorder system specified in claim 2 further including storage means resettable on command by the patient's physician and responsive to the operation of said automatic defibrillator to separately register one or more of: (a) the number of fibrillation episodes experienced by a patient between visits to the physician; (b) the number of defibrillation impulses applied to the patient's heart during a defibrillation attempt; (c) the time interval elapsing between the patient's last examination by a physician and the initial fibrillation episode occurring thereafter; and (d) the time interval elapsing between examinations by a physician.

Claim 9

The recorder system specified in claim 1 wherein said recorder system is implantable and further including communications means partly implantable and partly external to the patient's body for communicating a readout command selected by the patient's physician to said recorder system effective to initiate readout from said first and second storage means and transmission of the data stored by said storage means to external receiving apparatus.

Claim 10

The recorder system specified in claim 3 wherein said commandable readout means includes multiplexing means for arranging the digital code word stored in said memory means into a serial data output bit stream.

Claim 11

The recorder system specified in claim 8 wherein said recorder system further includes means for specially encoding the transmission to said external receiver apparatus for each particular patient.

Claim 12

The recorder system specified in claim 8 wherein said recorder system further includes means rendered effective upon communication of said readout command to initiate transmission by said communications means of a predetermined transmission pattern preceding the transmission of said stored data for synchronizing said external receiver apparatus to said data transmission.

Claim 13

The recorder system specified in claim 9 further including: communications means for transmitting said serial data output bit stream to said receiver apparatus, clocking means for establishing the data bit rate for said data output bit stream, means responsive to said clocking means for generating a predetermined bit pattern, and means rendered effective upon communication of a readout command to initiate transmission of said predetermined bit pattern prior to transmission of said serial data output bit stream for synchronizing said receiver apparatus to the data bit rate of said data output bit stream.

Claim 14

The recorder system specified in claim 8 further including means for controlling said communications means to transmit said data at least twice each time a readout command is selected by the patient's physician.

Claim 15

The recorder system specified in claim 13 wherein said communications means continuously transmit said data so long as a readout command is continuously selected by the patient's physician. 11 GB 2 060 174 A 11

Claim 16

The recorder system specified in claim 4 further including means controlled by the patient's 60 physician for selectively commanding said first alarm and second service request warning signals, 5 as desired.

Claim 17

A recorder system responsive to a selected physiological signal of a patient for monitoring, storing and reading out, on command, data regarding a particular physiological functioning represented by said physiological signal, said recorder system comprising: means for sampling and converting said physiological signal from an analog form into a corresponding digital data signal format, addressable memory means for storing the digital data signal, said memory means being divided into first and second storage portions, means for repeatedly addressing the first storage portion of said memory prior to the occurrence of a preselected physiological event to continually update the digital data stored in said first storage portion, means rendered effective upon the occurrence of said preselected physiological event to hold the most recent digital data then stored in said first storage portion corresponding to a first predetermined interval preceding said event, means rendered effective upon the occurrence of said preselected physiological event for thereafter addressing the second storage portion of said memory to store the digital data corresponding to said physiological signal during a 90 second predetermined interval following said event, and commandable means for reading out the digital data stored in each of said first and second storage portions of said memory.

Claim 18

A recorder system responsive to a selected physiological signal of a patient for monitoring, storing and reading out, on command, data regarding a particular physiological functioning represented by said physiological signal, said recorder system comprising: means for sampling and converting said physiological signal from an analog form into a corresponding digital data signal format, addressable memory means for storing the digital data signal, said memory means being divided into first and second storage portions, means for repeatedly addressing the first storage portion of said memory prior to the occurrence of a preselected physiological event to continually update the digital data stored in said first storage portion, means rendered effective upon the occurrence of said preselected physiological event to hold the most recent digital data then stored in said first storage portion corresponding to a first predetermined interval preceding said event, means rendered effective upon the occurrence of said preselected physiological event for thereafter addressing the second storage portion of said memory to store the digital data corresponding to said physiological signal during a 90 second predetermined interval following said event, and commandable means for reading out the digital data stored in each of said first and second storage portions of said memory.

Claim 19

The recording system specified in claim 16 wherein said physiological signal is converted from an analog form to a succession of multiple bit digital data words and wherein said addressable memory means comprises a plurality of random access memory (RAM) stages corresponding in number to the number of data bits in each digital data word, whereby each RAM stage is associated with a predetermined bit position in each digital data word.

Claim 20

The recording system specified in claim 17 wherein said commandable readout means includes multiplexing means for arranging the digital data bits stored in said RAM stages into a serial data output bit stream during readout.

Claim 21

The recorder system specified in claim 16 further including means rendered effective upon the occurrence of said preselected physiological event for providing a distinctive warning signal to the patient indicative of said event occurrence.

Claim 22

The recording system specified in claim 18 wherein said sampling and converting means, said memory means and said multiplexing means of the recording system are implantable in thd patient's body and wherein said commandable readout means comprises means partly internal' and partly external to the patient's body for communicating an externally selected readout command signal to the implanted portion of the recording system, and further including implanted transmitter means rendered effective following communication of said readout command for transmitting said serial data output bit stream to external receiver apparatus.

Claim 23

2 1. The recorder system as specified in claim 16 further including timing means resettable by the patient's physician and responsive to the occurrence of said preselected physiological event for providing a registration of selected time interval information of interest to a physician in analyzing the patient's physiological functioning represented by said physiological signal.

Claim 24

The recorder system specified in claim 21 wherein said timing means comprises a source means for generating time clocking pulses and resettable pulse counter means connected to said source means and responsive to said physiological signal for registering a running count of the number of time clocking pulses to demarcate said selected time interval information.

Claim 25

The recorder system specified in claim 22 wherein said time interval information includes the time interval between the patient's last examination by a physician and said event occurrence and the time interval between examinations.

Claim 26

The recorder system specified in claim 23 further including event counter means responsive to said physiological signal for registering a count of the number of said physiological events occurring between examinations.

Claim 27

The recorder system specified in claim 24 wherein said signal sampling and converting means, said memory means, said pulse counter means and said event counter means are implantable in the patient's body and further including: - implantable multiplexing means for arranging the data stored in said memory means and the count registrations of said pulse and event counter means into a serial bit stream format, and implantable transmitter means operably connected to said multiplexing means for transmitting said serial bit stream to external apparatus for display.

Claim 28

A recorder system substantially as herein described with reference to the accompanying drawings. Printed for Her Majesty's Stationery Office by the Courier Press, Leamington Spa, 1981. Published by the Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained.

Claim 29

A recorder system substantially as herein described with reference to the accompanying drawings. Printed for Her Majesty's Stationery Office by the Courier Press, Leamington Spa, 1981. Published by the Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained.