Implantable medical interventional device
First Claim
1. An implantable medical interventional device for treatment of pathologic tachycardias, comprising:
- first sensor means adapted to detect cardiac activity of the patient in which the interventional device is implanted for producing a first electrical signal representative of such cardiac activity including heart rate of the patient,second sensor means adapted to detect movement and lack of movement indicative of physical activity and inactivity of the patient for producing a second electrical signal representative of the patient'"'"'s activity status,generator means for selectively generating electrical waveforms to be applied to the patient'"'"'s heart to break a pathologic tachycardia, andcontrol means setting a predetermined heart rate and responsive to said first and second electrical signals as complementary criteria for distinguishing a heart rate of the patient exceeding the predetermined rate during a period of physical activity by the patient indicative of a pathologic tachycardia requiring treatment from a physiologic tachycardia attributable to patient activity, and including activation means responsive to a decision by said control means that the patient is experiencing a pathologic tachycardia for triggering said generator means to generate an electrical waveform having characteristics selected to break the tachycardia.
3 Assignments
0 Petitions
Accused Products
Abstract
An implantable medical interventional device responds to detection of cardiac activity of the patient indicative of ventricular tachycardia (VT) or fibrillation (VF) by successively applying to the patient'"'"'s heart selected ones of different electrical waveforms for treatment to break the VT or VF, respectively, until the monitored cardiac activity indicates that the treatment has been successful. An accelerometer adapted to sense position and movement of the patient along three mutually orthogonal axes acts as an activity status sensor to detect physical activity and inactivity of the patient to complement the detection of the patient'"'"'s cardiac activity for confirming that a detected VT is a pathologic tachycardia rather than a physiologic tachycardia, and in response to such confirmation the device selects an appropriate electrical waveform for the treatment. The device is capable of recognizing from detected physical activity the occurrence of a sudden vigorous movement associated with a syncope by calculating variances relative to the mean of the detected physical activity, and of responding to such recognition by selecting a defibrillating waveform for immediate application to the patient'"'"'s heart. A scoring system based on assigned weightings of subparameters of detected cardiac activity and detected physical activity or inactivity is used to determine the likelihood that a physiologic tachycardia, a pathologic tachycardia, or fibrillation is being detected.
-
Citations
29 Claims
-
1. An implantable medical interventional device for treatment of pathologic tachycardias, comprising:
-
first sensor means adapted to detect cardiac activity of the patient in which the interventional device is implanted for producing a first electrical signal representative of such cardiac activity including heart rate of the patient, second sensor means adapted to detect movement and lack of movement indicative of physical activity and inactivity of the patient for producing a second electrical signal representative of the patient'"'"'s activity status, generator means for selectively generating electrical waveforms to be applied to the patient'"'"'s heart to break a pathologic tachycardia, and control means setting a predetermined heart rate and responsive to said first and second electrical signals as complementary criteria for distinguishing a heart rate of the patient exceeding the predetermined rate during a period of physical activity by the patient indicative of a pathologic tachycardia requiring treatment from a physiologic tachycardia attributable to patient activity, and including activation means responsive to a decision by said control means that the patient is experiencing a pathologic tachycardia for triggering said generator means to generate an electrical waveform having characteristics selected to break the tachycardia. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. In combination with an implantable defibrillator adapted to selectively deliver electrical waveform therapies to a patient'"'"'s heart in response to detection of cardiac activity indicative of ventricular tachycardia or fibrillation, the improvement comprising:
control means for discriminating between pathologic tachycardia and physiologic tachycardia during the patient'"'"'s engagement in physical activity, said control means including implantable complementary sensor means for detecting movement indicative of physical activity of the patient, computing means responsive to detected physical activity and confirming detected cardiac activity of the patient indicative of pathologic tachycardia for recognizing a sudden brief movement by the patient as syncope, and generator means responsive to recognition of syncope by said computing means for generating a predetermined antitachycardia electrical waveform therapy to be delivered to the patient'"'"'s heart to revive the patient. - View Dependent Claims (14, 15, 16)
-
17. A method of timing the delivery of antitachycardia and defibrillating electrical therapies to a patient'"'"'s heart from an automatic implanted defibrillator device, comprising the device-implemented steps of:
-
detecting the current status of the patient'"'"'s physical activity while simultaneously detecting the patient'"'"'s cardiac activity to recognize a ventricular tachycardia while the patient is engaged in physical activity, determining the degree of probability that the recognized ventricular tachycardia is a pathologic tachycardia rather than a physiologic tachycardia by weighting the detected cardiac activity and the detected status of physical activity of the patient as separate indicia of the degree of probability that a pathologic tachycardia is occurring, and delivering an antitachycardia electrical therapy to the patient'"'"'s heart when the weighting indicates a predetermined degree of probability that a pathologic tachycardia is occurring. - View Dependent Claims (18, 19, 20)
-
-
21. An implantable medical device for intervention in response to the implant patient experiencing a syncope, comprising:
-
first sensor means for detecting electrical cardiac activity of the patient and for producing a first electrical signal representative thereof, second sensor means for detecting posture, position and physical activity of the patient and for producing a second electrical signal representative thereof, discrimination means responsive to said first and second electrical signals for discriminating between a physiologic tachycardia and a pathologic tachycardia of the patient'"'"'s heart, control means responsive to discrimination of a tachycardia by said discrimination means as a pathologic tachycardia for prescribing one among a plurality of different electrical therapy waveforms for treatment of the pathologic tachycardia, and generator means responsive to the prescribing of one of said electrical therapy waveforms by said control means for generating the prescribed waveform for application to the patient'"'"'s heart, said discrimination means including computing means responsive to said second electrical signal representative of detected physical activity of the patient by said second sensor means for recognizing therefrom the occurrence of a collapse of the patient associated with a syncope, said control means including means responsive to said recognizing by said computing means for prescribing defibrillating waveform from among said plurality of electrical therapy waveforms for treatment of the syncope. - View Dependent Claims (22, 23, 24)
-
-
25. A method of determining when to apply any of a plurality of available antitachycardia therapies, including possible defibrillation therapy, to a patient'"'"'s heart from an implantable antitachycardia device, comprising the steps of:
-
providing said plurality of antitachycardia therapies, detecting at least two different physiologic parameters of the patient from which hemodynamic events for treatment with said therapies are discernible, one of said parameters representing electrical cardiac activity of the patient, processing the detected different physiologic parameters to obtain a variety of subparameters identifying characteristics of the respective detected different physiologic parameters from which said subparameters were obtained, scoring each of the processed subparameters by assigning to it a relative value according to its importance in signifying the probability of occurrence of a predetermined hemodynamic event, and adding the relative values of the processed subparameters to obtain a cumulative score, and selecting one of the provided plurality of anti-tachycardia therapies prescribed as best suited for treatment of the predetermined hemodynamic event when the cumulative score of the processed subparameters reaches a preestablished level of probability that said predetermined hemodynamic event is occurring. - View Dependent Claims (26, 27)
-
-
28. A method of controlling the delivery of an appropriate therapy of an antitachycardia device configured and adapted to be implanted in a patient, which includes:
-
monitoring the posture, position and physical activity of the patient by use of at least two two-dimensional accelerometers carried by the patient to detect movement of the patient along three mutually orthogonal axes, detecting the patient'"'"'s ECG, processing the detected movement of the patient to obtain information on posture, position and physical activity of the patient, and processing the detected ECG of the patient to obtain information thereon, using the information obtained from both detected movement and detected ECG and a comparison thereof to distinguish a physiologic tachycardia from a pathologic tachycardia of the patient'"'"'s heart, and, if a pathologic tachycardia is found, triggering the antitachycardia device to deliver a predetermined therapy therefrom predetermined as most appropriate to terminate the pathologic tachycardia.
-
-
29. A control device for controlling the therapeutic function of an antitachycardia device configured and adapted to be implanted in a patient, said control device including:
-
accelerometer means for detecting state of physical activity of the patient and at least one of posture and position of the patient, and ECG means for detecting the ECG of the patient, verification means for comparing the detected state of physical activity of the patient and said at least one of posture and position of the patient against the detected ECG of the patient to distinguish a physiologic tachycardia from a pathologic tachycardia of the patient'"'"'s heart, and trigger means for actuating said antitachycardia device to apply a preselected antitachycardia therapy to the patient upon determination that the patient is experiencing a pathologic tachycardia.
-
Specification