US 4,958,632 A · Adaptable, digital computer controlled cardiac pacemaker

Abstract

A multi-mode, adaptable, implantable pacemaker is described including a microprocessor and memory programmed or capable of being programmed with a variety of processes for stimulating the patient's heart and/or for sensing and transmitting to a device external of the patient's body, various conditions of or activities of the patient's heart, or conditions of the pacemaker itself. The pacemaker includes a multiplexer by which a variety of analog and digital inputs are accessed under the control of the microprocessor and operated upon by the processes stored in the memory and executed by the microprocessor. The output of the pacemaker comprises a plurality of latch drivers and switches, which are selectively operable to apply stimulation to the patient's heart, as well as to sense signals indicative of the patient's heart activity as well as other internal conditions. The pacemaker is capable of transmitting these signals via a link such as an RF or acoustical link to an external monitoring apparatus. The external apparatus may transmit code signals to be received by the pacemaker, whereby the pacemaker's memory may be reprogrammed, dependent upon change of the patient's condition. Illustratively, the memory is divided into a plurality of blocks and control signals may be sent from the external apparatus to address the initial or starting location within another block, whereby another, selected program or process may be executed by the microprocessor.

Claims54

Dependent claims

Body implantable electrical apparatus coupled via a plurality of leads to body tissue, said apparatus comprising:

(a) means for applying electrical pulses via the leads to the body tissue;
(b) memory means including at least first and second storage portions, each storage portion storing a distinct set of instructions;
(c) control means for selectively executing one of the sets of instructions stored in said memory means, and comprising addressing means for accessing one of said first and second storage portions and a microprocessor for selectively applying addresses from said addressing means to said memory to control the execution of a selected program, said control means coupled to said appying means to effect control of the electrical pulses;
(d) means for selectively changing the address of said addressing means, whereby a different set of instructions is addressed by said addressing means and the instructions of the addressed set executed in order by said control means, whereby the character of the electrical pulses applied to the body tissue is changed accordingly;
and
(e) resetting means coupled to said microprocessor for periodically generating a reset signal to reset said address means to a predetermined return address, whereby if said address means inadvertently addresses a meaningless location in said memory means, the execution by said microprocessor of a selected program within said memory will be continued by addressing the predetermined return address within the selected program.

3 more elements

Body implantable electrical apparatus coupled via a plurality of leads to body tissue, said apparatus comprising:

(a) means for applying electrical pulses via the leads to the body tissue;
(b) memory means including at least first and second storage portions, each storage portion storing a distinct set of instructions;
(c) control means for selectively executing one of the sets of instructions stored in said memory means, and comprising addressing means for accessing one of said first and second storage portions, said control means coupled to said applying means to effect control of the electrical pulses;
(d) means for selectively changing the address of said addressing means, whereby a different set of instructions is addressed by said addressing means and the instructions of the addressed set executed in order by said control means, whereby the character of the electrical pulses aplied to the body tissue is changed accordingly;
and
(e) multiplexer means having at least first and second inputs for each receiving a respective input signal indicative of the set of instructions to be addressed, said multiplexer means coupled to said control means for receiving control signals from said control means for selectively applying the input signal appearing at a selected one of its first and second inputs to said control means.

3 more elements

Body implantable cardiac pacer apparatus coupled by first and second leads to corresponding first and second portions of a patient's heart, whereby stimulating pulses are applied thereto, said apparatus comprising:

(a) memory means including at least first and second storage portions, each storing a different program of stimulating the patient's heart;
(b) a microcomputer comprising control means for selectively executing one of the programs stored in said memory means and address means for addressing the program stored within a selected storage portion of said memory means;
(c) first and second select switch means adapted to be coupled respectively to the first and second leads, whereby stimulating pulses are applied to the first portion of the patient's heart and heart activity signals of the second portion of the heart sensed;
and
(d) decode means responsive to signals derived from said memory means generated by the execution by said microcomputer of a selected program within said memory means, said decode means generating a first control signal to operate said first select switch means to apply for a first timing period a stimulating pulse by the first lead to stimulate the first portion of the patient's heart, and a second control signal to operate said second select switch means for a second different timing period to apply the sensed heart activity signal appearing on the second lead to be processed by said microcomputer.

2 more elements

A microprocessor controlled cardiac pacemaker pulse generator comprising:

(a) terminal means adapted to couple electrical signals to and from the heart of the patient;
(b) sense means coupled to said terminal means for sensing electrical signals indicative of the patient's heart activity and providing a sense reset signal;
(c) triggerable pulse generating circuit means for generating a stimulating pulse at said terminal means;
(d) clock means for providing a series of clock signals;
(e) memory means for storing control programs and having at least one portion thereof forming resettable counter means coupled to said clock means for counting said clock signals;
and
(f) digital control means coupled to said terminal means and said sense means and including a micropocessor for executing programs as stored in said memory means, output means responsive to said counter means reaching a predetermined count for triggering said triggerable pulse generating means, and resetting means responsive to said output means and to said sense reset signal for resetting said counter means to an initial count.

4 more elements

A digital cardiac pacemaker for generating and applying stimulating pulses to a patient's heart in accordance with a pacing mode, said pacing mode comprised of a given sequence of operating states, said pacemaker comprising:

(a) terminal means adapted to couple the stimulating pulses to the patient's heart;
(b) triggerable pulse generating circuit means for generating a stimulating pulse at said terminal means;
(c) clock means for providing a series of clock signals;
(d) memory means for storing control parameters in the form of a plurality of counts;
and
(e) digital control means operable in a selected one of a plurality of states and including means for defining said selected state, counter means responsive to the clock signals for counting a selected one of a plurality of counts, and means responsive to said selected state in which said digital control means is operative for selecting one of the plurality of counts and for sequentially transferring the selected counts from said memory means to said counter means to be counted.

3 more elements

A digital cardiac pacemaker for generating and applying stimulating pulses to a patient's heart, the elements of said pacemaker being energized by an energy source, said packmaker comprising:

(a) terminal means adapted for coupling stimulating pulses to a patient's heart;
(b) triggerable pulse generating circuit means for generating stimulating pulses at said terminal means;
(c) means for providing a manifestation of the output level of the energy source;
(d) memory means for storing control parameters defining the characteristics of the stimulating pulses applied to the patient's heart;
(e) control means responsive to the output level manifestation for selecting at least one of said control parameters and for controlling the characteristics of the stimulating pulses in accordance with said one selected control parameter.

2 more elements

A digital computer controlled cardiac pacemaker for generating and applying stimulating pulses to a patient's heart in accordance with a pacing mode comprised of a distinctive sequence and number of operating states, said pacemaker comprising:

(a) a plurality of terminal means, first terminal means of said plurality adapted to couple the stimulating pulses to the patient's heart and second terminal means of said plurality adapted to provide signals indicative of the heart's condition;
(b) triggerable pulse generating circuit means for generating stimulating pulses;
(c) a plurality of switch means coupled to corresponding ones of said plurality of terminal means;
and
(d) control means comprising:
(1) memory means for storing a manifestation indicative of said sequence and number of operating states of the pacing mode and control parameters defining the characteristics of a plurality of operating states;
(2) means for operating said cardiac pacemaker in one, current operating state at a time before operating said cardiac pacemaker in another operating state in accordance with said distinctive number and sequence of operating states of said pacing mode;
(3) means responsive to said current operating state for addressing said memory means to read out and transfer addressed control parameters to said operating means, whereby the characteristics of the stimulating pulses are controlled;
and
(4) decoder means responsive to selected of said addressed control parameters for closing corresponding ones of said plurality of said switch means dependent on said operating state in which said cardiac pacemaker is disposed.

7 more elements

A digital computer controlled cardiac pacemaker for generating and applying stimulating pulses to a patient's heart in accordance with a selected one of a plurality of pacing modes, one of said pacing modes comprising at least a sensing state, each pacing mode comprised of a distinctive sequence and number of operating states, said pacemaker comprising:

(a) terminal means adapted to couple the stimulating pulses to the patient's heart, said terminal means is adapted to receive electrical signals indicative of the patient's heart activity;
(b) triggerable pulse generating circuit means for generating and applying stimulating pulses at said terminal means;
(c) sense means coupled to said terminal means and operative in an enabled condition for applying the patient's heart activity signals to said control means and in a disabled condition for blocking the patient's heart activity signals;
and
(d) control means including a digital computer, said control means comprising:
(1) memory means for storing a value indicative of the sequence and number of operating states of said plurality of pacing modes, and control parameters defining the characteristics of a plurality of operating states and comprising counts as stored in said memory means,
(2) means for variably selecting one of said pacing modes, said one selected pacing mode comprising a sensing state,
(3) means responsive to said selected one pacing mode for addressing said memory means to determine the number and sequence of said operating states of said one selected pacing mode,
(4) means for operating said digital cardiac pacemaker in one, current operating state at a time before operating said digital cardiac pacemaker in another operating state in accordance with said determined number and sequence of said operating states of said one selected pacing mode, and when operating said digital cardiac pacemaker in said sense state to dispose said sense means to its enabled condition to apply the patient's heart activity signals to said control means, said operating means comprising clock means for providing a series of clock signals and counter means responsive to the clock signals for counting a selected one of said counts, and
(5) means responsive to said current operating state for addressing said memory means to read out and transfer said addressed control parameter to said operating means whereby the characteristics of said one current operating state are controlled, said parameter addressing means responsive to said current operating state for addressing and transferring a count from said memory means to said counter means, said counter means counting said selected, transferred count to effect timing of said current state.

7 more elements

Dependencies are inferred from the claim text.

Adaptable, digital computer controlled cardiac pacemaker

Life of this patent

Adaptable, digital computer controlled cardiac pacemaker

Life of this patent

Abstract

Claims54