# US 2013/0158616 A1 · Implantable Device For Evaluating Autonomic Cardiovascular Drive In A Patient Suffering From Chronic Cardiac Dysfunction > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0158616 A1 - Document ID: US20130158616A1 - Status: Published application - Kind: A1 - Application number: 13/314,133 - Filed: 2011-12-07 - Published: 2013-06-20 - Earliest claimed: 2011-12-07 - Assignees: Cyberonics, Inc. - Inventors: Imad Libbus; Badri Amurthur; Bruce H. KenKnight - Web page: https://patentgrep.com/patent/US20130158616A1 ## CPC - A61N 1/36167: {Timing, e.g. stimulation onset} - A61B 5/02: Detecting, measuring or recording for evaluating the cardiovascular system, e.g. pulse, heart rate, blood pressure or blood flow - A61B 5/02438: {with portable devices, e.g. worn by the patient} - A61B 5/4836: {Diagnosis combined with treatment in closed-loop systems or methods (A61B5/0036 takes precedence)} - A61B 5/686: {Permanently implanted devices, e.g. pacemakers, other stimulators, biochips (A61B5/6861 takes precedence)} - A61N 1/05: for implantation or insertion into the body, e.g. heart electrode (A61N1/06 takes precedence) - A61N 1/0551: {Spinal or peripheral nerve electrodes} - A61N 1/36053: {adapted for vagal stimulation (A61N1/36114 takes precedence)} - A61N 1/36114: {Cardiac control, e.g. by vagal stimulation (stimulating the heart A61N1/362)} - A61N 1/36139: {with automatic adjustment} - 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 An implantable device for evaluating autonomic cardiovascular drive in a patient suffering from chronic cardiac dysfunction is provided. A stimulation therapy lead includes helical electrodes configured to conform to an outer diameter of a cervical vagus nerve sheath, and a set of connector pins electrically connected to the helical electrodes. A neurostimulator includes an electrical receptacle into which the connector pins are securely and electrically coupled. The neurostimulator also includes a pulse generator configured to therapeutically stimulate the vagus nerve through the helical electrodes in alternating cycles of stimuli application and stimuli inhibition that are tuned to both efferently activate the heart's intrinsic nervous system and afferently activate the patient's central reflexes by triggering bi-directional action potentials. The neurostimulator includes a recordable memory storing a baseline heart rate. The neurostimulator includes an integrated leadless heart rate sensor configured to continually monitor heart rate in light of the baseline heart rate. ## Claims ### Claim 1 A vagus nerve neurostimulator for evaluating autonomic cardiovascular drive, comprising: an implantable neurostimulator comprising: a pulse generator configured to deliver electrical therapeutic stimulation tuned to restore autonomic balance through continuously-cycling, intermittent and periodic electrical pulses simultaneously delivered at a periodic duty cycle in a range between 5% and 30%, at an intensity that avoids acute physiological side effects and with an unchanging cycle not triggered by physiological markers in both afferent and efferent directions of a cervical vagus nerve through a pair of helical electrodes via an electrically coupled nerve stimulation therapy lead; and a leadless heart rate sensor configured to continually monitor heart rate against a stored baseline heart rate. ### Claim 2 (depends on 1) A neurostimulator according to claim 1, wherein the pulse generator is further configured to suspend the electrical therapeutic stimulation for a fixed period of time in response to the monitored heart rate falling below a stored lower bound, after which the electrical therapeutic stimulation resumes. ### Claim 3 (depends on 1) A neurostimulator according to claim 1, wherein the pulse generator is further configured to gradually down titrate the electrical therapeutic stimulation in response to the monitored heart rate falling below a stored lower bound. ### Claim 4 (depends on 3) A neurostimulator according to claim 3, wherein the pulse generator is further configured to suspend the electrical therapeutic stimulation for a fixed period of time and gradually up titrate the electrical therapeutic stimulation after the down titration. ### Claim 5 (depends on 1) A neurostimulator according to claim 1, wherein the pulse generator is further configured to gradually up titrate the electrical therapeutic stimulation in response to the monitored heart rate rising above a stored upper bound. ### Claim 6 An implantable device for evaluating autonomic cardiovascular drive, comprising: an implantable neurostimulator comprising a pulse generator configured to deliver electrical therapeutic stimulation tuned to restore autonomic balance at an intensity that avoids acute physiological side effects and with an unchanging cycle not triggered by physiological markers through continuously-cycling, intermittent and periodic electrical pulses simultaneously delivered at a periodic duty cycle in a range between 5% and 30% in both afferent and efferent directions of a cervical vagus nerve in continuous alternating cycles of stimuli application and stimuli inhibition; a cervical vagus nerve stimulation therapy lead electrically coupled to the pulse generator and terminated by a pair of helical electrodes through which the therapeutic electrical stimulation is delivered to the cervical vagus nerve; and an integrated leadless heart rate sensor configured to continually monitor heart rate against a baseline heart rate stored in a memory in the pulse generator. ### Claim 7 (depends on 6) An implantable device according to claim 6, wherein the pulse generator is further configured to suspend the therapeutic electrical stimulation for a fixed period of time in response to the monitored heart rate falling below a lower bound stored in the memory that is indicative of at least one of bradycardia and asystole, after which the therapeutic electrical stimulation resumes. ### Claim 8 (depends on 6) An implantable device according to claim 6, wherein the pulse generator is further configured to gradually down titrate the therapeutic electrical stimulation in response to the monitored heart rate falling below a lower bound stored in the memory that is indicative of at least one of bradycardia and asystole. ### Claim 9 (depends on 8) An implantable device according to claim 8, wherein the pulse generator is further configured to suspend the therapeutic electrical stimulation for a fixed period of time and gradually up titrate the therapeutic electrical stimulation after the down titration. ### Claim 10 (depends on 6) An implantable device according to claim 6, wherein the pulse generator is further configured to gradually up titrate the therapeutic electrical stimulation in response to the monitored heart rate rising above an upper bound stored in the memory that is indicative of insufficient therapy delivery. ### Claim 11 (depends on 6) An implantable device according to claim 6, further comprising: a connector pin and an insulated electrical lead body that further comprise the therapy lead and which are electrically connected to the helical electrodes; and an electrical receptacle comprised on an outer surface of the neurostimulator into which the connector pin is securely and electrically connected to the pulse generator. ### Claim 12 An implantable device for evaluating autonomic cardiovascular drive in a patient suffering from chronic cardiac dysfunction, comprising: a cervical vagus nerve stimulation therapy lead, comprising: a pair of helical electrodes configured to conform to an outer diameter of a cervical vagus nerve sheath of a patient; and a set of connector pins electrically connected to the helical electrodes by an insulated electrical lead body; and a neurostimulator powered by a primary battery and enclosed in a hermetically sealed housing, further comprising: an electrical receptacle comprised on an outer surface of the housing into which the connector pins are securely and electrically coupled; a pulse generator configured to therapeutically stimulate the cervical vagus nerve through the helical electrodes in alternating cycles of stimuli application and stimuli inhibition that are tuned to restore autonomic balance at an intensity that avoids acute physiological side effects and with an unchanging cycle not triggered by physiological markers through continuously-cycling, intermittent and periodic electrical pulses simultaneously delivered at a periodic duty cycle in a range between 5% and 30% in both afferent and efferent directions of the vagus nerve to both efferently activate the heart's intrinsic nervous system and afferently activate the patient's central reflexes by triggering bi-directional action potentials; a recordable memory within which is stored a baseline heart rate for the patient prior to stimulation therapy initiation; and an integrated leadless heart rate sensor configured to continually monitor the patient's heart rate in light of the baseline heart rate. ### Claim 13 (depends on 12) An implantable device according to claim 12, wherein the integrated leadless heart rate sensor is further configured to sense the baseline heart rate during a time period prior to stimulation therapy initiation. ### Claim 14 (depends on 12) An implantable device according to claim 12, wherein the integrated leadless heart rate sensor is further configured to determine the baseline heart rate as at least one of a direct measurement of heart rate, an average heart rate over time, a minimum heart rate over time, a maximum heart rate over time, and a mean heart rate over time. ### Claim 15 (depends on 12) An implantable device according to claim 12, wherein the baseline heart rate is programmed into the recordable memory prior to stimulation therapy initiation. ### Claim 16 (depends on 12) An implantable device according to claim 12, wherein the baseline heart rate is determined by ECG measurements other than the patient's heart rate prior to stimulation therapy initiation and thereafter programmed into the recordable memory. ### Claim 17 (depends on 12) An implantable device according to claim 12, wherein a lower bound, which is indicative of at least one of bradycardia and asystole, defined below the baseline heart rate, is stored in the recordable memory and the pulse generator is further configured to suspend the triggering of the bi-directional action potentials for a fixed period of time in response to the sensed heart rate falling below the lower bound, after which the triggering of the bi-directional action potentials resumes. ### Claim 18 (depends on 17) An implantable device according to claim 17, wherein the lower bound is expressed as at least one of a ratio, a percentile, a function, and discrete independent values with respect to the baseline heart rate. ### Claim 19 (depends on 12) An implantable device according to claim 12, wherein a lower bound, which is indicative of at least one of bradycardia and asystole, defined below the baseline heart rate, is stored in the recordable memory and the pulse generator is further configured to gradually down titrate the triggering of the bi-directional action potentials in response to the sensed heart rate falling below the lower bound. ### Claim 20 (depends on 19) An implantable device according to claim 19, wherein the pulse generator is further configured to suspend the triggering of the bi-directional action potentials for a fixed period of time and gradually up titrate the triggering of the bi-directional action potentials after the down titration. ### Claim 21 (depends on 12) An implantable device according to claim 12, wherein an upper bound, which is indicative of insufficient therapy delivery, defined above the baseline heart rate, is stored in the recordable memory and the pulse generator is further configured to gradually up titrate the triggering of the bi-directional action potentials in response to the sensed heart rate rising above the upper bound. ### Claim 22 (depends on 21) An implantable device according to claim 21, wherein the upper bound is expressed as at least one of a ratio, a percentile, a function, and discrete independent values with respect to the baseline heart rate.