# US 8,788,028 B2 · Parasympathetic stimulation to enhance tachyarrhythmia detection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,788,028 B2 - Document ID: US8788028B2 - Status: Granted - Kind: B2 - Application number: 12/845,505 - Filed: 2010-07-28 - Published: 2012-02-02 - Granted: 2014-07-22 - Earliest claimed: 2010-07-28 - Assignees: Medtronic, Inc. - Applicants: Arun Kumar; Shailesh Kumar Vishnu Musley - Inventors: Arun Kumar; Shailesh Kumar Vishnu Musley - Web page: https://patentgrep.com/patent/US8788028B2 ## CPC - A61N 1/36585: {controlled by two or more physical parameters} - A61N 1/3962: {in combination with another heart therapy} - A61N 1/39622: {Pacing therapy} - A61N 1/36114: {Cardiac control, e.g. by vagal stimulation (stimulating the heart A61N1/362)} - 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) ## Abstract This disclosure is directed toward techniques for classifying a tachycardia as supraventricular tachycardia or ventricular tachycardia. A method comprises detecting a tachycardia based on at least one value of a cardiac interval, delivering vagal stimulation in response to the detection of the tachycardia, sensing a physiological parameter other than the cardiac interval during or subsequent to delivering the vagal stimulation, and classifying the tachycardia as supraventricular or ventricular based on the sensed physiological parameter. In some examples, the method includes sensing a response of a physiological parameter other than cardiac rate to the vagal stimulation, such as pressure or a morphological characteristic of the cardiac electrical waveform. The method may include providing an indication to a user based on the classification of supraventricular tachycardia, or delivery of appropriate electrical therapy based on the classification of ventricular tachycardia or ventricular fibrillation. ## Claims ### Claim 1 A method comprising: detecting a tachycardia based on at least one value of a cardiac interval; delivering vagal stimulation in response to the detection of the tachycardia; sensing a physiological parameter other than the cardiac interval during or subsequent to delivering the vagal stimulation; and classifying the tachycardia as supraventricular or ventricular based on the sensed physiological parameter. ### Claim 2 (depends on 1) The method of claim 1, wherein classifying the tachycardia comprises classifying the tachycardia as supraventricular based on the sensed physiological parameter, the method further comprising providing an indication to a user based on the classification of supraventricular tachycardia. ### Claim 3 (depends on 1) The method of claim 1, wherein classifying the tachycardia comprises classifying the tachycardia as supraventricular based on the sensed physiological parameter, the method further comprising withholding a defibrillation therapy based on the classification of supraventricular tachycardia. ### Claim 4 (depends on 1) The method of claim 1, further comprising comparing at least one waveform characteristic of a signal indicative of a cardiac depolarization and corresponding to the tachycardia to a template, wherein delivering vagal stimulation comprises delivering the vagal stimulation based on the comparison. ### Claim 5 (depends on 1) The method of claim 1, wherein the sensed physiological parameter comprises at least one waveform characteristic of a signal indicative of a cardiac depolarization, the method further comprising comparing the at least one waveform characteristic to a template, and wherein classifying the tachycardia comprises classifying the tachycardia as supraventricular or ventricular based on the comparison. ### Claim 6 (depends on 1) The method of claim 1, further comprising determining a value of a blood pressure of the patient, wherein delivering vagal stimulation comprises delivering the vagal stimulation based on the blood pressure value. ### Claim 7 (depends on 1) The method of claim 1, wherein sensing the physiological parameter comprises sensing a value of a blood pressure of the patient, and wherein classifying the tachycardia comprises classifying the tachycardia based on the value of the blood pressure of the patient. ### Claim 8 (depends on 7) The method of claim 7, wherein sensing the value of the blood pressure comprises sensing blood pressure within at least one of a chamber of a heart or an artery of the patient. ### Claim 9 (depends on 7) The method of claim 7, wherein sensing the value of the blood pressure comprises sensing blood pressure within a right ventricle of the patient. ### Claim 10 (depends on 1) The method of claim 1, wherein delivering vagal stimulation comprises delivering the vagal stimulation to at least one of a sinoatrial node fat pad or an atrioventricular node fat pad of the patient. ### Claim 11 (depends on 1) The method of claim 1, wherein delivering vagal stimulation comprises delivering the vagal stimulation to a cardiac branch of a vagus nerve of the patient. ### Claim 12 (depends on 1) The method of claim 1, wherein delivering vagal stimulation comprises delivering at least one of delivering the vagal stimulation intracardially or epicardially. ### Claim 13 A system comprising: a stimulation generator configured to deliver vagal stimulation to a patient; a processor configured to detect a tachycardia based on at least one value of a cardiac interval; and an arrhythmia discrimination module configured to control the stimulation generator to deliver the vagal stimulation in response to the detection of the tachycardia, detect a physiological parameter other than the cardiac interval during or subsequent to the stimulation generator delivering the vagal stimulation, and classify the tachycardia as supraventricular or ventricular based on the detected physiological parameter. ### Claim 14 (depends on 13) The system of claim 13, further comprising a user interface configured to provide an indication in response to the arrhythmia discrimination module classifying the tachycardia as supraventricular. ### Claim 15 (depends on 14) The system of claim 14, further comprising at least one of a programmer comprising the user interface or a computing device comprising the user interface. ### Claim 16 (depends on 13) The system of claim 13, wherein the processor is configured to control the stimulation generator to withhold a defibrillation therapy in response to the classification of the tachycardia as supraventricular. ### Claim 17 (depends on 13) The system of claim 13, wherein the arrhythmia discrimination module is configured to compare at least one waveform characteristic of a signal indicative of cardiac depolarization and corresponding to the tachycardia to a template and control the stimulation generator to deliver the vagal stimulation based on the comparison. ### Claim 18 (depends on 13) The system of claim 13, wherein the detected physiological parameter comprises at least one waveform characteristic of a signal indicative of a cardiac depolarization, wherein the arrhythmia discrimination module is configured to compare the at least one waveform characteristic to a template and classify the tachycardia as supraventricular or ventricular based on the comparison. ### Claim 19 (depends on 13) The system of claim 13, wherein the arrhythmia discrimination module is configured to detect a value of a blood pressure of the patient and control the stimulation generator to deliver the vagal stimulation based on the blood pressure value. ### Claim 20 (depends on 13) The system of claim 13, wherein the physiological parameter comprises a value of a blood pressure of the patient, and wherein the arrhythmia discrimination module is configured to classify the tachycardia based on the value of the blood pressure of the patient. ### Claim 21 (depends on 20) The system of claim 20, further comprising a sensor configured to sense the value of the blood pressure within at least one of a chamber of a heart or an artery of the patient, wherein the arrhythmia discrimination module is configured to receive the value of the blood pressure from the sensor. ### Claim 22 (depends on 21) The system of claim 21, wherein the sensor is configured to sense the value of the blood pressure within a right ventricle of the patient. ### Claim 23 (depends on 13) The system of claim 13, further comprising an implantable medical device, wherein the implantable medical device comprises the stimulation generator, the processor, and the arrhythmia discrimination module. ### Claim 24 (depends on 13) The system of claim 13, further comprising at least one lead including one or more electrodes, wherein the stimulation generator is configured to deliver the vagal stimulation to the patient via the one or more electrodes of the at least one lead. ### Claim 25 A non-transitory computer-readable medium comprising instructions for causing a programmable processor to: detect a tachycardia based on at least one value of a cardiac interval; deliver vagal stimulation in response to the detection of the tachycardia; sense a physiological parameter other than the cardiac interval during or subsequent to delivering vagal stimulation; and classify the tachycardia as supraventricular or ventricular based on the sensed physiological parameter. ### Claim 26 A system comprising: means for detecting a tachycardia based on at least one value of a cardiac interval; means for delivering vagal stimulation in response to the detection of the tachycardia; means for sensing a physiological parameter other than the cardiac interval during or subsequent to delivering vagal stimulation; and means for classifying the tachycardia as supraventricular or ventricular based on the sensed physiological parameter. ### Claim 27 A method comprising: detecting a tachycardia based on at least one value of a cardiac interval; delivering vagal stimulation in response to the detection of thetachycardia; sensing a physiological parameter during or subsequent to delivering vagal stimulation; classifying the tachycardia as supraventricular based on the sensed physiological parameter; and providing an indication to the user based on the classification of supraventricular tachycardia. ### Claim 28 (depends on 13) The system of claim 13, wherein the arrhythmia discrimination module is configured to: determine a value of the physiological parameter after detecting the tachycardia and prior to the vagal stimulation; determine if the detected physiological parameter during or subsequent to the vagal stimulation has changed relative to a value prior to the vagal stimulation; and classify the tachycardia as supraventricular in response to determining the detected physiological parameter has changed relative to the value prior to the vagal stimulation. ### Claim 29 (depends on 28) The system of claim 28, wherein the arrhythmia detection module is configured to control the stimulation generator to deliver the vagal stimulation during an atrial refractory period. ### Claim 30 A system comprising: a stimulation generator configured to deliver vagal stimulation to a patient; a processor configured to detect a tachycardia based on at least one value of a cardiac interval; an arrhythmia discrimination module configured to control the stimulation generator to deliver the vagal stimulation in response to the detection of the tachycardia, detect a physiological parameter other than the cardiac interval during or subsequent to the stimulation generator delivering the vagal stimulation, and classify the tachycardia as supraventricular or ventricular based on the detected physiological parameter; and a sensor configured to sense a value of a blood pressure of the patient, wherein the physiological parameter comprises the value of a blood pressure of the patient, the arrhythmia discrimination module further configured to classify the tachycardia based on the value of the blood pressure detected during or subsequent to the vagal stimulation if the value of the cardiac interval is not increased during or subsequent to the vagal stimulation. ### Claim 31 (depends on 30) The system of claim 30, wherein the arrhythmia discrimination module is further configured to classify the tachycardia as supraventricular based on a decrease in the value of the blood pressure and the value of the cardiac interval is not increased during or subsequent to the vagal stimulation. ### Claim 32 (depends on 31) The system of claim 31, wherein the sensor is an implantable sensor and the blood pressure is a ventricular pressure.