|Publication number||US7277747 B2|
|Application number||US 10/996,340|
|Publication date||Oct 2, 2007|
|Filing date||Nov 23, 2004|
|Priority date||Nov 23, 2004|
|Also published as||US20060111643|
|Publication number||10996340, 996340, US 7277747 B2, US 7277747B2, US-B2-7277747, US7277747 B2, US7277747B2|
|Inventors||Shelley Cazares, Julie Thompson, Yayun Lin|
|Original Assignee||Cardiac Pacemakers, Inc.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (110), Non-Patent Citations (21), Referenced by (27), Classifications (11), Legal Events (5)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This patent application is related to the following co-pending and commonly assigned applications: U.S. patent application Ser. No. 10/995,655, entitled “Tachyarrhythmia Therapy Selection Based On Patient Response Information,” filed on Nov. 23, 2004; and U.S. patent application Ser. No. 10/995,704, entitled “Template Generation Based On Patient Response Information”, filed on Nov. 23, 2004, both of which are hereby incorporated by reference.
This patent document pertains generally to administration of antitachyarrhythmia therapy, and more particularly, but not by way of limitation, to arrhythmia memory for tachyarrhythmia discrimination.
Arrhythmia is an abnormal rhythm of the heart. A tachyarrhythmia is an abnormally fast heart rhythm. A tachyarrhythmia originating in the ventricular region of the heart is called a ventricular tachyarrhythmia (VT). Ventricular tachyarrhythmia can produce symptoms of fainting, dizziness, weakness, blind spots, and potentially, unconsciousness and cardiac arrest. A tachyarrhythmia that does not originate from the ventricular region of the heart is called a supraventricular tachyarrhythmia (SVT). An SVT episode typically originates from an impulse arising in the atrium, the atrioventricular node (AV node), or the bundle of His. SVT episodes tend to be much less lethal than VT episodes.
Treatment for cardiac tachyarrhythmia can be administered by a medical device, such as a pacemaker or a defibrillator, which can be implanted in the human body. These devices can be configured to sense an intrinsic electrical heart signal and analyze the signal to determine whether a tachyarrhythmia is occurring. Such devices can also be configured to deliver antitachyarrhythmia therapy, such as electric stimulation. Improved cardiac rhythm management methods and systems are needed.
In the drawings, which are not necessarily drawn to scale, like numerals describe substantially similar components throughout the several views. Like numerals having different letter suffixes represent different instances of substantially similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.
The following detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments, which are also referred to herein as “examples,” are described in enough detail to enable those skilled in the art to practice the invention. The embodiments may be combined, other embodiments may be utilized, or structural, logical and electrical changes may be made without departing from the scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims and their equivalents.
In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one. In this document, the term “or” is used to refer to a nonexclusive or, unless otherwise indicated. Furthermore, all publications, patents, and patent documents referred to in this document are incorporated by reference herein in their entirety, as though individually incorporated by reference. In the event of inconsistent usages between this document and those documents so incorporated by reference, the usage in the incorporated reference(s) should be considered supplementary to that of this document; for irreconcilable inconsistencies, the usage in this document controls.
In varying examples, a morphological template can be generated from a tachyarrhythmia episode and used to identify a later episode. For example, a tachyarrhythmia episode can be detected by an implantable medical device and analyzed to determine whether the episode is a type that necessitates antitachyarrhythmia therapy. In one example, a morphological graph of a tachyarrhythmia episode is presented to a human analyst, such as a physician, and an assessment of the tachyarrhythmia episode is received from the human analyst. The assessment can, for example, include an input that indicates whether the human analyst deems the tachyarrhythmia episode is a VT episode or a SVT episode. In another example, the tachyarrhythmia episode can be analyzed by a computer to determine whether it is a VT or SVT episode. The computer can be in an implanted medical device, or external to the patient. A morphological template can be generated from the tachyarrhythmia episode and later used to identify a similar episode as it is occurring. For example, if a tachyarrhythmia episode correlates with an SVT template, an SVT can be declared, i.e. the episode can be identified as an SVT and treated accordingly. Templates can be selected or discarded based a variety of factors including conditions in the patient or characteristics of arrhythmias.
In an example, a template is a sampled data representation of a heart depolarization. In another example, a template is a set of selected features from a sampled data representation of a heart depolarization. In another example a template is generated from multiple SVT beats, for example by taking an average of several beats.
The memory circuit 60 includes a storage medium, such as solid state RAM. In an exemplary configuration, the processing circuit 30 sends data received from the sensing circuit 40 during a tachyarrhythmia episode to the memory circuit 60 and the memory circuit 60 stores the data for later reference. The processing circuit 30 also communicates with a wireless communication system 70. The wireless communication system 70 sends data to or receives data from an external system 80, which typically includes a display system on which a user can view a graphical representation of the data. The medical device 10 can be configured as an implantable device, but is not necessarily implantable. While one processing circuit is shown, examples of the medical device including multiple processors are also possible. In varying examples, the processor is in a device implanted in the patient, or in a device such that is external to the patient, such as a programmer or a remote computer system.
At 260, the device declares the second portion of the heart signal to represent a SVT episode if the degree of similarity exceeds a threshold valued. In one example, a processor in the medical device declares a SVT episode if a feature correlation coefficient for a heart beat exceeds a threshold. In another example, a processor declares a SVT if multiple feature correlation coefficients for respective multiple beats exceed a threshold value. In one scenario, a SVT is declared if a specified fraction of heart beats in a sequence of beats (e.g. 3 out of 10 beats) exhibit a feature correlation coefficient that exceeds a threshold. In another example, a SVT is declared if an average feature correlation coefficient for a number of beats exceeds a threshold (e.g. the average for 10 beats≧0.94).
In an example, the processor determines a degree of similarity between the second portion and multiple SVT templates. In one example, the processor begins determining degrees of similarity for the second portion for a sequence of templates and stops determining the degree of similarity if the degree of similarity for one of the templates exceeds a threshold. In other words, the processor compares the heart signal to a sequence of templates until a template match is found or all the templates are used. In another example, the portion of the heart signal is compared to all of the templates regardless of whether a match is found, and an SVT is declared if the degree of similarity for any one of the templates exceeds a threshold.
In addition to supraventricular tachyarrhythmia (SVT) episodes, a heart can exhibit other types of tachyarrhythmia that do not warrant antitachyarrhythmia therapy, including some instances ventricular tachyarrhythmia (VT). Such other non-lethal VT episodes can also be identified and used to generate templates.
Referring again to
In an alternative embodiment, in lieu of presenting a graphical representation to a user and receiving an input, a portion of the heart signal is analyzed automatically by a processor to determine whether antitachyarrhythmia therapy is appropriate.
Alternatively, at 325, a candidate SVT template is selected based other information about the patient. In an example, the drug treatment regimen of a patient is considered in the selection of a SVT template. The morphology of SVT episodes in a patient can vary depending upon the drug treatment regimen of the patient. In one example, the medical device stores information about drug treatment regimens associated with the tachyarrhythmia episodes used to generate the candidate templates. The current drug regimen is also stored in the device. The processor selects a SVT template based upon a similarity between the drug treatment associated with the selected template and the current drug treatment. In another example, the medical device detects one or more of neural activity, patient activity, sleep state, hemodynamic status, transthoracic impedance, or cardiac impedance. In further examples, the device detects REM (random eye movement) status, sympathetic/parasympathetic tone, intercardiac blood pressure including right ventricular pressure, left atrial pressure, or pulmonary artery pressure, oxygen saturation, heart size and contractability, blood flow, or edema. In varying examples, the medical device considers one or more of these parameters in selecting an SVT template. In another example, the processor identifies one or more characteristics of the patient, and selects a SVT template using statistics from other patients having similar characteristics. In varying examples, the characteristics include (but are not limited to) as height, weight, age, disease history, medication, and patient status (such as neural activity, blood pressure, etc.)
In another alternative, at 330, a candidate SVT template is selected based upon multiple factors. In an example, both the heart rate and the drug treatment regimen are taken into consideration.
At 335, the processor determines a degree of similarity between the heart signal from the later tachyarrhythmia episode and the selected SVT template. The processor compares the degree of similarity to at least one threshold, at 340. If the degree of similarity falls below a threshold, a SVT episode is not declared. In an example, if a SVT episode is not declared, the medical device declares a VT episode at 341 and delivers a ventricular antitachyarrhythmia therapy at 342. Alternatively, other determinations can be made before the medical device administers ventricular antitachyarrhythmia therapy.
If the degree of similarity does exceed a threshold, the medical device declares the heart signal from the later tachyarrhythmia episode to represent a SVT episode at 345. The medical device then suppresses ventricular antitachyarrhythmia therapy at 350.
If the tachyarrhythmia portion of the heart signal is not similar to the NSR template, at 440 the medical device determines a degree of similarity between a portion of the heart signal and a SVT template. At 445, the medical device determines whether the degree of similarity exceeds a threshold. If the degree of similarity exceeds a threshold, the medical device declares the portion of the heart signal to represent a SVT episode at 450. In an example, declaring the portion of the heart signal to represent a SVT episode merely means making a determination to executing a response that is consistent with a SVT, such as suppressing a ventricular antitachyarrhythmia episode at 455.
If, at 445, the degree of similarity does not exceed a threshold, the medical device stores the tachyarrhythmia portion of the heart signal at 460. The stored portion is displayed to a user at 465 and an input is received from the user at 470. At 475, if the user indicates that the heart signal is indicative of SVT, a template is generated from the tachyarrhythmia portion of the heart signal, at 480.
While the present examples have generally been described in terms of an implanted or implantable device, the presently described examples can also be implemented in non-implantable devices and systems.
Varying algorithms can be used to generate a template and determine the degree of similarity between a heart signal and a template. In one example, a set of pre-determined rules are used to locate a number of points on a waveform, and those points are used as the template for comparison against a heart signal. In an example, eight pre-determined points can be located. In one example, the maxima, minima, and inflection points are located. The located points are stored as the template. Features are extracted from a portion of the heart signal by aligning the portion of the heart signal with the template. In an example, a peak on the template is aligned with a peak on the portion of the heart signal from one beat of a tachyarrhythmia episode. The amplitude of the points on the portion of the heart signal is measured at times corresponding to the points in the template. To determine the degree of similarity, a feature correlation coefficient (FCC) is computed using the amplitudes measured from the signal and the amplitude in the template. Computation of the feature correlation coefficient is further described in U.S. Pat. No. 6,708,058, which is incorporated herein by reference in its entirety.
In an example, a cardiac rate channel signal and a shock channel signal are sensed. The rate channel signal is measured from a sensing tip to a distal coil on a lead. The shock channel is measured from a distal coil to a proximal coil of the RV lead. A fiducial point is determined from the cardiac rate channel signals. A shock channel signal is aligned using the fiducial point. A template is generated using the aligned shock channel signal. Use of signals from rate and shock channels is further described in U.S. Pat. No. 6,708,058, which is incorporated by reference in its entirety. In other examples, a signal is sensed and then aligned using the same channel from which it was sensed.
In another example, a processor computes a wavelet transform or Fourier transform of the signal from which a template is to be generated. A predetermined number of largest wavelet coefficients are saved as a template. Features are extracted from a heart signal by aligning the peak of the signal with the peak of the template and computing the wavelet transform of the aligned tachy beat waveform. A predetermined number of largest wavelet coefficients are saved. The sum of the absolute value of the differences between the saved wavelet coefficients and the wavelet coefficients in the template is determined and divided by the sum of absolute value of the wavelet coefficients in the template. The resulting value is subtracted from 1 and multiplied by 100 to provide a “percent match score”, which is compared to a threshold. In an example, the threshold is 70%, and beats having a percent match score greater than or equal to 70% are considered SVT in origin. In an example, if 3 out of 8 beats are SVT, an SVT episode is declared. Wavelet-based algorithms are further discussed in U.S. Pat. Nos. 6,393,316 and 5,782,888, which are incorporated herein by reference in their entirety.
In another example, a heart signal waveform is approximated as three consecutive triangles. The areas of each of the triangles is calculated and saved in a template. To extract features from a portion of a heart signal, peaks in the heart signal are aligned with the template, and the heart signal is approximated as three triangles. The area of each of the three triangles is calculated. To determine the degree of similarity to the template, a “similarity score” is determined based on the sum of the differences in the areas of the signal triangles and the template triangle. The similarity score is inversely proportional to this sum. If the similarity score is greater than a threshold, the beat is considered SVT in origin. If a predetermined number of beats exceed a threshold, an SVT episode is declared.
The preceding descriptions of techniques for determining a degree of similarity are considered exemplary. Other techniques, or variations of the described techniques, can be employed with the methods described in this application.
It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.
The Abstract of the Disclosure is provided to comply with 37 C.F.R. §1.72(b), requiring an abstract that will allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US4023564||Jan 26, 1976||May 17, 1977||Spacelabs, Inc.||Arrhythmia detector|
|US4336810||Sep 30, 1980||Jun 29, 1982||Del Mar Avionics||Method and apparatus for arrhythmia analysis of ECG recordings|
|US4589420||Jul 13, 1984||May 20, 1986||Spacelabs Inc.||Method and apparatus for ECG rhythm analysis|
|US4680708||Nov 5, 1984||Jul 14, 1987||Washington University||Method and apparatus for analyzing electrocardiographic signals|
|US4721114||Feb 21, 1986||Jan 26, 1988||Cardiac Pacemakers, Inc.||Method of detecting P-waves in ECG recordings|
|US4802491||Jul 30, 1986||Feb 7, 1989||Massachusetts Institute Of Technology||Method and apparatus for assessing myocardial electrical stability|
|US4809697||Oct 14, 1987||Mar 7, 1989||Siemens-Pacesetter, Inc.||Interactive programming and diagnostic system for use with implantable pacemaker|
|US4825869||Sep 28, 1987||May 2, 1989||Telectronics N.V.||System for automatically performing a clinical assessment of an implanted pacer based on information that is telemetrically received|
|US4830006||Jun 17, 1986||May 16, 1989||Intermedics, Inc.||Implantable cardiac stimulator for detection and treatment of ventricular arrhythmias|
|US4884345||May 12, 1988||Dec 5, 1989||Siemens-Pacesetter, Inc.||Adjustable template for pacemaker ECG analysis and method of use|
|US4940054||Apr 29, 1988||Jul 10, 1990||Telectronics N.V.||Apparatus and method for controlling multiple sensitivities in arrhythmia control system including post therapy packing delay|
|US4947857||Feb 1, 1989||Aug 14, 1990||Corazonix Corporation||Method and apparatus for analyzing and interpreting electrocardiograms using spectro-temporal mapping|
|US4989610||Nov 16, 1987||Feb 5, 1991||Spacelabs, Inc.||Method and system of ECG data review and analysis|
|US5000189||Nov 15, 1989||Mar 19, 1991||Regents Of The University Of Michigan||Method and system for monitoring electrocardiographic signals and detecting a pathological cardiac arrhythmia such as ventricular tachycardia|
|US5014698||Oct 2, 1989||May 14, 1991||Leonard Bloom||Method of and system for monitoring and treating a malfunctioning heart|
|US5020540||Aug 22, 1989||Jun 4, 1991||Biometrak Corporation||Cardiac biopotential analysis system and method|
|US5046504||Apr 6, 1990||Sep 10, 1991||Corazonix Corporation||Method and apparatus for analyzing and interpreting electrocardiograms using spectro-temporal mapping|
|US5047930||Jun 26, 1987||Sep 10, 1991||Nicolet Instrument Corporation||Method and system for analysis of long term physiological polygraphic recordings|
|US5127401||Nov 9, 1990||Jul 7, 1992||Medtronic, Inc.||Method of and apparatus for multi-vector pacing artifact detection|
|US5183040||Mar 8, 1991||Feb 2, 1993||Telectronics Pacing Systems, Inc.||Apparatus and method for detecting abnormal cardiac rhythms using an ultrasound sensor in an arrhythmia control system|
|US5184615||Mar 8, 1991||Feb 9, 1993||Telectronics Pacing Systems, Inc.||Apparatus and method for detecting abnormal cardiac rhythms using evoked potential measurements in an arrhythmia control system|
|US5193535||Aug 27, 1991||Mar 16, 1993||Medtronic, Inc.||Method and apparatus for discrimination of ventricular tachycardia from ventricular fibrillation and for treatment thereof|
|US5193550||Nov 30, 1990||Mar 16, 1993||Medtronic, Inc.||Method and apparatus for discriminating among normal and pathological tachyarrhythmias|
|US5215098||Aug 12, 1991||Jun 1, 1993||Telectronics Pacing Systems, Inc.||Data compression of cardiac electrical signals using scanning correlation and temporal data compression|
|US5217021||Jul 30, 1991||Jun 8, 1993||Telectronics Pacing Systems, Inc.||Detection of cardiac arrhythmias using correlation of a cardiac electrical signals and temporal data compression|
|US5240009||Mar 25, 1991||Aug 31, 1993||Ventritex, Inc.||Medical device with morphology discrimination|
|US5266554||Dec 14, 1992||Nov 30, 1993||Ciba-Geigy Corporation||Heterocyclic compounds|
|US5269301||Oct 19, 1992||Dec 14, 1993||Leonard Bloom||Multimode system for monitoring and treating a malfunctioning heart|
|US5271411||Sep 10, 1991||Dec 21, 1993||Colin Electronics Co., Ltd.||Method and apparatus for ECG signal analysis and cardiac arrhythmia detection|
|US5273049||Apr 9, 1992||Dec 28, 1993||Telectronics Pacing Systems, Inc.||Detection of cardiac arrhythmias using template matching by signature analysis|
|US5280792||Sep 18, 1992||Jan 25, 1994||The University Of Sydney||Method and system for automatically classifying intracardiac electrograms|
|US5292348||Apr 13, 1992||Mar 8, 1994||Telectronics Pacing Systems, Inc.||Implantable cardioverter/defibrillator and method employing cross-phase spectrum analysis for arrhythmia detection|
|US5299118||Sep 5, 1991||Mar 29, 1994||Nicolet Instrument Corporation||Method and system for analysis of long term physiological polygraphic recordings|
|US5311873||Aug 28, 1992||May 17, 1994||Ecole Polytechnique||Comparative analysis of body surface potential distribution during cardiac pacing|
|US5311874||May 18, 1992||May 17, 1994||Cardiac Pacemakers, Inc.||Method for tachycardia discrimination|
|US5312445||Feb 3, 1992||May 17, 1994||Telectronics Pacing Systems, Inc.||Implantable cardiac stimulating apparatus and method employing detection of P-waves from signals sensed in the ventricle|
|US5313953||Jan 14, 1992||May 24, 1994||Incontrol, Inc.||Implantable cardiac patient monitor|
|US5330504||May 3, 1993||Jul 19, 1994||Telectronics Pacing Systems, Inc.||Cardioverting defibrillating device with off-line ECG analysis|
|US5331966||Dec 16, 1993||Jul 26, 1994||Medtronic, Inc.||Subcutaneous multi-electrode sensing system, method and pacer|
|US5350406||Dec 22, 1992||Sep 27, 1994||Ela Medical||Apparatus and method of control for an implanted anti-tachycardia device|
|US5360436||Apr 3, 1992||Nov 1, 1994||Intermedics, Inc.||Cardiac pacing responsive to multiple activity types|
|US5366487||Nov 4, 1993||Nov 22, 1994||Angeion Corporation||Fibrillation and tachycardia detection|
|US5379776||Dec 1, 1993||Jan 10, 1995||Telectronics Pacing Systems, Inc.||Heart rhythm classification method, and implantable dual chamber cardioverter/defibrillator employing the same|
|US5400795||Oct 22, 1993||Mar 28, 1995||Telectronics Pacing Systems, Inc.||Method of classifying heart rhythms by analyzing several morphology defining metrics derived for a patient's QRS complex|
|US5404880||Oct 5, 1993||Apr 11, 1995||Board Of Regents Of University Of Nebraska||Scatter diagram analysis system and method for discriminating ventricular tachyarrhythmias|
|US5417221||May 7, 1993||May 23, 1995||Psytech, Inc.||Method and apparatus for distinguishing electric signal waveforms|
|US5421830||Aug 27, 1993||Jun 6, 1995||Pacesetter, Inc.||Programming system having means for recording and analyzing a patient's cardiac signal|
|US5447519||Mar 19, 1994||Sep 5, 1995||Medtronic, Inc.||Method and apparatus for discrimination of monomorphic and polymorphic arrhythmias and for treatment thereof|
|US5447524||Jul 25, 1994||Sep 5, 1995||Intermedics, Inc.||Cardiac pacing method and apparatus responsive to multiple activity types|
|US5456261||Dec 16, 1993||Oct 10, 1995||Marquette Electronics, Inc.||Cardiac monitoring and diagnostic system|
|US5458620||Feb 14, 1994||Oct 17, 1995||Angeion Corporation||Cardiac arrhythmia detection using interdependent multiple parameter settings|
|US5458623||Mar 4, 1994||Oct 17, 1995||Telectronics Pacing Systems, Inc.||Automatic atrial pacing threshold determination utilizing an external programmer and a surface electrogram|
|US5462060||May 24, 1994||Oct 31, 1995||Ela Medical, S.A.||Methods and apparatus for determining when tachyarrythmia is pace-terminable|
|US5464433||Jun 14, 1994||Nov 7, 1995||Incontrol, Inc.||Atrial defibrillator and method providing dual reset of an interval timer|
|US5513644||Sep 22, 1994||May 7, 1996||Pacesetter, Inc.||Cardiac arrhythmia detection system for an implantable stimulation device|
|US5527347||Feb 21, 1995||Jun 18, 1996||Medtronic, Inc.||Dual chamber pacing system and method with automatic adjustment of the AV escape interval for treating cardiomyopathy|
|US5542430||Sep 16, 1994||Aug 6, 1996||Telectronics Pacing Systems, Inc.||Apparatus and method for discriminating between cardiac rhythms on the basis of their morphology using a neural network|
|US5549641||Oct 31, 1994||Aug 27, 1996||Incontrol, Inc.||Atrial fibrillation type selective cardiovertor and method|
|US5549654||Apr 15, 1994||Aug 27, 1996||Medtronic, Inc.||Interactive interpretation of event markers in body-implantable medical device|
|US5560369||Sep 22, 1994||Oct 1, 1996||Pacesetter, Inc.||Cardiac arrhythmia detection system for an implantable stimulation device and method|
|US5605159||Feb 16, 1996||Feb 25, 1997||Smith; Joseph M.||System and method for determining spatial organization of atrial activation|
|US5609158||May 1, 1995||Mar 11, 1997||Arrhythmia Research Technology, Inc.||Apparatus and method for predicting cardiac arrhythmia by detection of micropotentials and analysis of all ECG segments and intervals|
|US5622178||May 4, 1994||Apr 22, 1997||Spacelabs Medical, Inc.||System and method for dynamically displaying cardiac interval data using scatter-plots|
|US5628326||Nov 29, 1995||May 13, 1997||Hewlett-Packard Company||Calculating a heart rate from an ECG waveform by discarding a percentage of R-R intervals prior to averaging|
|US5634468||Apr 2, 1993||Jun 3, 1997||Micromedical Industries Limited||Sensor patch and system for physiological monitoring|
|US5645070||Sep 25, 1995||Jul 8, 1997||Ventritex, Inc.||Method and apparatus for determining the origins of cardiac arrhythmias morphology dynamics|
|US5685315||Mar 29, 1996||Nov 11, 1997||Pacesetter, Inc.||Cardiac arrhythmia detection system for an implantable stimulation device|
|US5713367||Jan 26, 1995||Feb 3, 1998||Cambridge Heart, Inc.||Measuring and assessing cardiac electrical stability|
|US5718242||Jun 26, 1996||Feb 17, 1998||Pacesetter, Inc.||Cardiac arrhythmia detection system for an implantable stimulation device and method|
|US5725559||May 16, 1996||Mar 10, 1998||Intermedics Inc.||Programmably upgradable implantable medical device|
|US5730142||Mar 21, 1997||Mar 24, 1998||Medtronic, Inc.||Method and apparatus for detecting tachycardia|
|US5738105||Oct 24, 1995||Apr 14, 1998||Angeion Corporation||Method and apparatus for sensing R-waves using both near field and far field sensing simultaneously|
|US5749900||Dec 11, 1995||May 12, 1998||Sulzer Intermedics Inc.||Implantable medical device responsive to heart rate variability analysis|
|US5755739||Dec 4, 1996||May 26, 1998||Medtronic, Inc.||Adaptive and morphological system for discriminating P-waves and R-waves inside the human body|
|US5779645||Dec 17, 1996||Jul 14, 1998||Pacesetter, Inc.||System and method for waveform morphology comparison|
|US5782888||Mar 21, 1997||Jul 21, 1998||Medtronic, Inc.||Method of selecting an operating mode for an implantable medical device|
|US5788717||Jul 11, 1995||Aug 4, 1998||Pacesetter, Inc.||Atrial rate determination and atrial tachycardia detection in a dual-chamber implantable pacemaker|
|US5792065||Mar 18, 1997||Aug 11, 1998||Marquette Medical Systems, Inc.||Method and apparatus for determining T-wave marker points during QT dispersion analysis|
|US5792066||Jan 9, 1997||Aug 11, 1998||Hewlett-Packard Company||Method and system for detecting acute myocardial infarction|
|US5795303||Sep 2, 1997||Aug 18, 1998||Ep Technologies, Inc.||Systems and methods for making time-sequential measurements of biopotentials sensed in myocardial tissue|
|US5797399||Apr 19, 1996||Aug 25, 1998||The Regents Of The University Of Michigan||Method and apparatus for identifying and correctly responding to abnormal heart activity|
|US5817027 *||Aug 27, 1997||Oct 6, 1998||Hewlett-Packard Company||Method and apparatus for classifying heartbeats in an ECG waveform|
|US5817133||Mar 4, 1997||Oct 6, 1998||Medtronic, Inc.||Pacemaker with morphological filtering of sensed cardiac signals|
|US5819007||Mar 15, 1996||Oct 6, 1998||Siemens Medical Systems, Inc.||Feature-based expert system classifier|
|US5827197||Nov 14, 1997||Oct 27, 1998||Incontrol, Inc.||System for detecting atrial fibrillation notwithstanding high and variable ventricular rates|
|US5855593||Jun 12, 1997||Jan 5, 1999||Medtronic, Inc.||Prioritized rule based method and apparatus for diagnosis and treatment for arrhythmias|
|US5857977||Aug 8, 1996||Jan 12, 1999||The Regents Of The University Of Michigan||Method and apparatus for separation of ventricular tachycardia from ventricular fibrillation for implantable cardioverter defibrillators|
|US5873897||Sep 19, 1997||Feb 23, 1999||Sulzer Intermedics Inc.||Method and apparatus for dual chambered tachyarrhythmia classification and therapy|
|US5944744||Feb 6, 1998||Aug 31, 1999||Sulzer Intermedics Inc.||Implantable cardiac stimulator with automatic electrogram profiling|
|US5951484||Jul 31, 1998||Sep 14, 1999||Harbinger Medical, Inc.||Method of noninvasively determining a patient's susceptibility to arrhythmia|
|US5961467||Apr 1, 1997||Oct 5, 1999||Shimazu; Hideaki||Cardiovascular system observation method|
|US6016442||Mar 25, 1998||Jan 18, 2000||Cardiac Pacemakers, Inc.||System for displaying cardiac arrhythmia data|
|US6091990||Nov 3, 1999||Jul 18, 2000||Cardiac Pacemakers, Inc.||System for grouping and displaying cardiac arrhythmia data|
|US6178350||Jan 19, 2000||Jan 23, 2001||Medtronic, Inc.||Prioritized rule based method and apparatus for diagnosis and treatment of arrhythmias|
|US6192273||Dec 2, 1997||Feb 20, 2001||The Cleveland Clinic Foundation||Non-programmable automated heart rhythm classifier|
|US6212428||May 22, 2000||Apr 3, 2001||Cardiac Pacemakers, Inc.||Multiple stage morphology-based system detecting ventricular tachycardia and supraventricular tachycardia|
|US6221011||Jul 26, 1999||Apr 24, 2001||Cardiac Intelligence Corporation||System and method for determining a reference baseline of individual patient status for use in an automated collection and analysis patient care system|
|US6223078 *||Mar 12, 1999||Apr 24, 2001||Cardiac Pacemakers, Inc.||Discrimination of supraventricular tachycardia and ventricular tachycardia events|
|US6230055||Aug 20, 1999||May 8, 2001||Cardiac Pacemakers, Inc.||Method and apparatus for adaptive tachycardia and fibrillation discrimination|
|US6233072||Dec 31, 1997||May 15, 2001||Mci Communications Corporation||Method and system for restoring coincident line and facility failures|
|US6233078||Apr 21, 1998||May 15, 2001||Nec Corporation||Photo signal amplification transmission system|
|US6275732 *||Jun 17, 1998||Aug 14, 2001||Cardiac Pacemakers, Inc.||Multiple stage morphology-based system detecting ventricular tachycardia and supraventricular tachycardia|
|US6430435 *||Nov 20, 2000||Aug 6, 2002||Cardiac Pacemakers, Inc.||Multiple state morphology-based system detecting ventricular tachycardia and supraventricular tachycardia|
|US6484055 *||Sep 20, 2000||Nov 19, 2002||Cardiac Pacemakers, Inc.||Discrimination of supraventricular tachycardia and ventricular tachycardia events|
|US20020032469 *||Nov 21, 2001||Mar 14, 2002||Cardiac Pacemakers, Inc.||Discrimination of supraventricular tachycardia and ventricular tachycardia events|
|US20030181818 *||Mar 25, 2002||Sep 25, 2003||Jaeho Kim||Method and system for characterizing a representative cardiac beat using multiple templates|
|US20030195572 *||Apr 12, 2002||Oct 16, 2003||Joseph Bocek||Method and system for characterizing supraventricular rhythm during cardiac pacing|
|US20040082973 *||Oct 23, 2002||Apr 29, 2004||Jaeho Kim||Characterization of supraventricular rhythm using collected cardiac beats|
|US20040116972 *||Dec 9, 2003||Jun 17, 2004||Cardiac Pacemakers, Inc.||Discrimination of supraventricular tachycardia and ventricular tachycardia events|
|US20040171959 *||Feb 27, 2003||Sep 2, 2004||Medtronic, Inc.||Detection of tachyarrhytmia termination|
|1||"Invitation to Pay Additional Fees and Partial Search Report for Application No. PCT/US2005/035641, dated Mar. 1, 2006", 7 pages.|
|2||"Vitality 2 Implantable Cardioverter Defibrillator System Guide", Guidant Corporation, (2004), cover pages and pp. 3-15 to 3-19.|
|3||Afonso, V. X., et al., "ECG Beat Detection Using Filter Banks", IEEE Transactions on Biomedical Engineering, 46(2), (Feb. 1999), 192-202.|
|4||Afonso, V. X., et al., "Filter Bank-based ECG Beat Classification", Proceedings of the 19th Annual International Conference of the IEEE, Engineering in Medicine and Biology society, (Oct. 30-Nov. 2, 1997), 97-100.|
|5||Afonso, V. X., et al., "Filter Bank-based ECG Beat Detection", Proceedings of the 18th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Amsterdam, The Netherlands,(1996), 1037-1038.|
|6||Afonso, V. X., et al., "Filter Bank-based Processing of the Stress ECG", IEEE 17th Annual Conference Engineering in Medicine and Biology Society, 2, (Sep. 1995), 887-888.|
|7||Afonso, V. X., et al., "Multirate Processing of the ECG using Filter Banks", Computers in Cardiology , (1996), 245-248.|
|8||Cazares, Shelley , "Cardiac Tachyarrhythmia Therapy Selection Based on Patient Response Information", U.S. Appl. No. 10/995,655, Filed Nov. 23, 2004, 50 pgs.|
|9||Cazares, Shelley , "Cardiac Template Generation Based on Patient Response Information", U.S. Appl. No. 10/995,704, Filed Nov. 23, 2004, 47 pgs.|
|10||Cazares, Shelley, et al., "Arrhythima Discrimination Based on Determination of Rate Dependency", U.S. Appl. No. 11/312,280, Filed Dec. 20, 2005, 41 Pages.|
|11||Cazares, Shelly, et al., "Discrimination Polymorphic and Monomorphic Cardiac Rhythms Using Template Generation", U.S. Appl. No. 11/312,279, Filed Dec. 20, 2005, 46 Pages.|
|12||Duru, Firat, et al., "The Potential for Inappropriate Ventricular Tachycardia Confirmation Using the Intracardiac Electrogram (EGM) Width Criterion", PACE, vol. 22, 1999, (Jul. 1999), 1039-1046.|
|13||Gold, Michael R., et al., "Advanced Rhythm Discrimination for Implantable Cardioverter Defibrillators Using Electrogram Vector Timing and Correlation", Journal of Cardiovascular Electrophysiology, vol. 13, No. 11, (Nov. 2002), pp. 1092-1097.|
|14||Grady, Thomas A., et al., "Prognostice Significance of Exercise-Induced Left Bundle-Branch Block", JAMA, vol. 279, No. 2, Jan. 14, 1998, 153-156.|
|15||Kerr, Martha , "Shock Rate Cut 70% with ICDs Programmed to First Deliver Antitachycardia Pacing: Results of the PainFREE Rx II Trial", NewsRhythms, MedScape CRM New, www.medscape.com, (2003), 2 pgs.|
|16||Kim, Jaeho , et al., "Blending Cardiac Rhythm Detection Processes", U.S. Appl. No. 11/089,185, Filed Mar. 24, 2005, 72 pgs.|
|17||Kinoshita, Shinji, et al., "Transient Disapperance of Complete Right Bundle Brach (BBB) During Exercise", Journal of Electrocardiology, vol. 29, No. 3, 1996, 255-256.|
|18||Li, Dan, "Method and Apparatus for Rate-Dependent Morphology-Based Cardiac Arrhythmia Classification", U.S. Appl. No. 11/151,567, Filed on Jun. 13, 2005, 53 pgs.|
|19||Morris, et al., "Intracardiac Electrogram Transformation: Morphometric Implications for Implantable Devices", Journal of Electrocardiology, 29 Supplement, (1996), pp. 124-129.|
|20||Stephany, et al., "Real-Time Estimation of Magnitude-Square Coherence for Use in Implantable Devices", IEEE Computers in Cardiology, (1992), pp. 375-378.|
|21||Wathen, Mark S., et al., "Shock reduction using antitachycardia pacing for spontaneous rapid ventricular tachycardia in patients with coronary artery disease", Circulation, 104(7), (Aug. 14, 2001), pp. 796-801.|
|Citing Patent||Filing date||Publication date||Applicant||Title|
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|US7725184||May 30, 2007||May 25, 2010||Cardiac Pacemakers, Inc.||Cardiac tachyarrhythmia therapy selection based on patient response information|
|US7729762||Nov 3, 2005||Jun 1, 2010||Cardiac Pacemakers, Inc.||Adaptive anti-tachycardia therapy apparatus and method|
|US7738950||Dec 21, 2006||Jun 15, 2010||Cardiac Pacemakers, Inc.||Method and apparatus for identifying potentially misclassified arrhythmic episodes|
|US7738957||Nov 3, 2005||Jun 15, 2010||Cardiac Pacemakers, Inc.||Tachyarrhythmia therapy device with ranked therapy selection|
|US7818056||Oct 19, 2010||Cardiac Pacemakers, Inc.||Blending cardiac rhythm detection processes|
|US7894893||Sep 30, 2004||Feb 22, 2011||Cardiac Pacemakers, Inc.||Arrhythmia classification and therapy selection|
|US7908001||Mar 15, 2011||Cardiac Pacemakers, Inc.||Automatic multi-level therapy based on morphologic organization of an arrhythmia|
|US8140153||Apr 30, 2010||Mar 20, 2012||Cardiac Pacemakers Inc.||Cardiac tachyarrhythmia therapy selection based on patient response information|
|US8145301||Mar 27, 2012||Cardiac Pacemakers, Inc.||Blending cardiac rhythm detection processes|
|US8185195||May 22, 2012||Cardiac Pacemakers, Inc.||Arrhythmia classification and therapy selection|
|US8317776||Nov 27, 2012||The Invention Science Fund I, Llc||Circulatory monitoring systems and methods|
|US8403881||May 19, 2008||Mar 26, 2013||The Invention Science Fund I, Llc||Circulatory monitoring systems and methods|
|US8409132||Apr 2, 2013||The Invention Science Fund I, Llc||Treatment indications informed by a priori implant information|
|US8483808||Sep 10, 2010||Jul 9, 2013||Yanting Dong||Methods and systems for characterizing cardiac signal morphology using K-fit analysis|
|US8532762||Dec 20, 2005||Sep 10, 2013||Cardiac Pacemakers, Inc.||Discriminating polymorphic and monomorphic cardiac rhythms using template generation|
|US8583228||Mar 15, 2011||Nov 12, 2013||Cardiac Pacemakers, Inc.||Automatic multi-level therapy based on morphologic organization of an arrhythmia|
|US8636670||May 13, 2008||Jan 28, 2014||The Invention Science Fund I, Llc||Circulatory monitoring systems and methods|
|US8639330||May 14, 2010||Jan 28, 2014||Cardiac Pacemakers, Inc.||Cardiac rhythm management system with arrhythmia classification and electrode selection|
|US8870813||May 22, 2008||Oct 28, 2014||The Invention Science Fund I, Llc||Circulatory monitoring systems and methods|
|US8948858||Apr 29, 2010||Feb 3, 2015||Cardiac Pacemakers, Inc.||Method and apparatus for identifying potentially misclassified arrhythmic episodes|
|US9119547 *||Jan 12, 2010||Sep 1, 2015||Cardiac Pacemakers, Inc.||Arrhythmia discrimination based on determination of rate dependency|
|US20060155201 *||Mar 21, 2006||Jul 13, 2006||Cardiac Pacemakers, Inc.||Cardiac rhythm management systems and methods using multiple morphology templates for discriminating between rhythms|
|US20060217621 *||Mar 24, 2005||Sep 28, 2006||Jaeho Kim||Blending cardiac rhythm detection processes|
|US20070142737 *||Dec 20, 2005||Jun 21, 2007||Shelley Cazares||Arrhythmia discrimination based on determination of rate dependency|
|US20080065165 *||Dec 21, 2006||Mar 13, 2008||Christopher Dale Johnson||Method and apparatus for identifying potentially misclassified arrhythmic episodes|
|US20100121209 *||Jan 12, 2010||May 13, 2010||Shelley Cazares||Arrhythmia Discrimination Based on Determination of Rate Dependency|
|U.S. Classification||600/518, 600/515|
|Cooperative Classification||A61B5/726, A61B5/04525, A61B5/0464, A61N1/3622, A61B5/0031|
|European Classification||A61B5/0452B, A61B5/0464, A61N1/362A2|
|Feb 24, 2005||AS||Assignment|
Owner name: CARDIAC PACEMAKERS, INC., MINNESOTA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CAZARES, SHELLEY;THOMPSON, JULIE;LIN, YAYUN;REEL/FRAME:015786/0580
Effective date: 20050217
|Mar 2, 2011||FPAY||Fee payment|
Year of fee payment: 4
|May 15, 2015||REMI||Maintenance fee reminder mailed|
|Oct 2, 2015||LAPS||Lapse for failure to pay maintenance fees|
|Nov 24, 2015||FP||Expired due to failure to pay maintenance fee|
Effective date: 20151002