# US 2014/0155949 A1 · Implantable neurostimulator-implemented method for managing bradycardia through vagus nerve stimulation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0155949 A1 - Document ID: US20140155949A1 - Status: Published application - Kind: A1 - Application number: 14/177,542 - Filed: 2014-02-11 - Published: 2014-06-05 - Earliest claimed: 2012-07-20 - Assignees: Cyberonics, Inc. - Applicants: Cyberonics, Inc. - Inventors: Imad Libbus; Badri Amurthur; Bruce H. KenKnight - Web page: https://patentgrep.com/patent/US20140155949A1 ## CPC - A61N 1/365: controlled by a physiological parameter, e.g. heart potential {(evoked response A61N1/371)} - A61B 5/363: Detecting tachycardia or bradycardia - A61N 1/36114: {Cardiac control, e.g. by vagal stimulation (stimulating the heart A61N1/362)} - A61N 1/36139: {with automatic adjustment} - A61N 1/36167: {Timing, e.g. stimulation onset} - A61N 1/36175: {Pulse width or duty cycle} - A61N 1/36171: {Frequency} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A method for managing bradycardia through vagus nerve stimulation is provided. An implantable neurostimulator configured to deliver electrical therapeutic stimulation in both afferent and efferent directions of a patient's cervical vagus nerve is provided. An operating mode is stored, which includes parametrically defining a maintenance dose of the electrical therapeutic stimulation tuned to restore cardiac autonomic balance through continuously-cycling, intermittent and periodic electrical pulses. The maintenance dose is delivered via a pulse generator through a pair of helical electrodes via an electrically coupled nerve stimulation therapy lead independent of cardiac cycle. The patient's physiology is monitored, and upon sensing a condition indicative of bradycardia, the delivery of the maintenance dose is suspended. A progressively increasing amount of time is spent waiting via a controller and, upon sensing a condition indicative of an absence or termination of the bradycardia, a progressively increasing partial maintenance dose is delivered via the pulse generator. ## Claims ### Claim 1 An implantable neurostimulator-implemented method for managing bradycardia through vagus nerve stimulation, comprising the steps of: defining a maintenance dose of electrical therapeutic stimulation for delivery via an implantable neurostimulator tuned to restore cardiac autonomic balance through continuously-cycling, intermittent and periodic electrical pulses; delivering the maintenance dose to a vagus nerve of a patient through a pair of helical electrodes via a stimulation therapy lead electrically coupled to a pulse generator comprised in the implantable neurostimulator, comprising: therapeutically delivering the maintenance dose via the pulse generator to the vagus nerve in both afferent and efferent directions of the vagus nerve independent of cardiac cycle; periodically monitoring the patient's physiology via a physiological sensor comprised in the implantable neurostimulator; upon sensing a condition indicative of bradycardia, suspending the delivery of the maintenance dose to the vagus nerve, comprising: determining a back-off delay comprising an amount of time that increases over each previous back-off delay via a controller comprised in the implantable neurostimulator; upon expiry of the back-off delay, checking the patient's physiology via the physiological sensor; and upon sensing a condition indicative of an absence or termination of the bradycardia, delivering the maintenance dose at a partial duty cycle to the vagus nerve via the pulse generator; resuming the periodic monitoring of the patient's physiology via the physiological sensor; and upon sensing a condition indicative of a continued absence of bradycardia, gradually increasing the duty cycle of the maintenance dose. ### Claim 2 (depends on 1) A method according to claim 1, further comprising the steps of: upon sensing a condition indicative of a recurrence of the bradycardia, re-suspending the delivery of the maintenance dose to the vagus nerve, comprising: exponentially increasing the back-off delay over a back-off delay most recently used during suspension of the delivery of the maintenance dose to the vagus nerve; and upon expiry of the increased back-off delay, checking the patient's physiology via the physiological sensor. ### Claim 3 (depends on 2) A method according to claim 2, further comprising the steps of: continuing the re-suspension of the delivery of the maintenance dose; and terminating the delivery of the maintenance dose to the vagus nerve once a maximum back-off delay has been reached. ### Claim 4 (depends on 1) A method according to claim 1, further comprising the step of: sensing the condition indicative of bradycardia based on at least one of abnormal sinus rhythm and heart rate falling below a minimum threshold. ### Claim 5 (depends on 1) A non-transitory computer readable storage medium storing code for executing on a computer system to perform the method according to claim 1. ### Claim 6 A method for managing bradycardia through vagus nerve stimulation, comprising the steps of: defining a maintenance dose of electrical therapeutic stimulation; delivering the maintenance dose to a vagus nerve of a patient independent of cardiac cycle; periodically monitoring the patient's physiology via a physiological sensor; upon sensing a condition indicative of bradycardia, suspending the delivery of the maintenance dose to the vagus nerve, comprising: determining a back-off delay comprising an amount of time that increases over each previous back-off delay; upon expiry of the back-off delay, checking the patient's physiology via the physiological sensor; and upon sensing a condition indicative of an absence or termination of the bradycardia, delivering the maintenance dose at a partial duty cycle to the vagus nerve; resuming the periodic monitoring of the patient's physiology; and upon sensing a condition indicative of a continued absence of bradycardia, gradually increasing the duty cycle of the maintenance dose. ### Claim 7 (depends on 6) A method according to claim 6, further comprising the steps of: upon sensing a condition indicative of a recurrence of the bradycardia, re-suspending the delivery of the maintenance dose to the vagus nerve, comprising: exponentially increasing the back-off delay over a back-off delay most recently used during suspension of the delivery of the maintenance dose to the vagus nerve; and upon expiry of the increasing back-off delay, checking the patient's physiology via the physiological sensor. ### Claim 8 (depends on 7) A method according to claim 7, further comprising the steps of: continuing the re-suspension of the delivery of the maintenance dose; and terminating the delivery of the maintenance dose to the vagus nerve once a maximum back-off delay has been reached. ### Claim 9 (depends on 6) A method according to claim 6, further comprising the step of: sensing the condition indicative of bradycardia based on at least one of abnormal sinus rhythm and heart rate falling below a minimum threshold. ### Claim 10 (depends on 6) A non-transitory computer readable storage medium storing code for executing on a computer system to perform the method according to claim 6. ### Claim 11 A method for managing bradycardia through vagus nerve stimulation, comprising the steps of: defining a maintenance dose of electrical therapeutic stimulation, wherein the electrical therapeutic stimulation comprises a pulsed electrical signal comprising: a signal ON time; a signal OFF time; an output current; a signal frequency of approximately 10 Hz; a pulse width; and a duty cycle defined by dividing the signal ON time by the sum of the signal ON time and signal OFF time; delivering the maintenance dose to a vagus nerve of a patient independent of cardiac cycle; periodically monitoring the patient's physiology via a physiological sensor; upon sensing a condition indicative of bradycardia, suspending the delivery of the maintenance dose to the vagus nerve, comprising: determining a back-off delay comprising an amount of time that increases over each previous back-off delay; upon expiry of the back-off delay, checking the patient's physiology via the physiological sensor; and upon sensing a condition indicative of an absence or termination of the bradycardia, delivering the maintenance dose at a partial duty cycle to the vagus nerve; resuming the periodic monitoring of the patient's physiology; and upon sensing a condition indicative of a continued absence of bradycardia, gradually increasing the duty cycle of the maintenance dose. ### Claim 12 (depends on 11) A method according to claim 11, further comprising the steps of: upon sensing a condition indicative of a recurrence of the bradycardia, re-suspending the delivery of the maintenance dose to the vagus nerve, comprising: exponentially increasing the back-off delay over a back-off delay most recently used during suspension of the delivery of the maintenance dose to the vagus nerve; and upon expiry of the increased back-off delay, checking the patient's physiology via the physiological sensor. ### Claim 13 (depends on 12) A method according to claim 12, further comprising the steps of: continuing the re-suspension of the delivery of the maintenance dose; and terminating the delivery of the maintenance dose to the vagus nerve once a maximum back-off delay has been reached. ### Claim 14 (depends on 11) A method according to claim 11, further comprising the step of: sensing the condition indicative of bradycardia based on at least one of abnormal sinus rhythm and heart rate falling below a minimum threshold. ### Claim 15 (depends on 11) A non-transitory computer readable storage medium storing code for executing on a computer system to perform the method according to claim 11. ### Claim 16 (depends on 11) A method according to claim 11, wherein the pulsed electrical signal further comprises a signal ramp-down time. ### Claim 17 (depends on 11) A method according to claim 11, wherein the pulsed electrical signal further comprises a signal ramp-up time.