818 results about "Defibrillation" patented technology

A body implantable lead comprises a lead body including a conductive polymer electrode disposed along a distal end portion of the lead body for performing one or more of the functions consisting of pacing, sensing, cardioversion and defibrillation. An electrical conductor, preferably in the form of a multistrand cable conductor, couples the conductive polymer electrode with a proximal end of the lead body. The conductive polymer electrode encapsulates the conductor and is in electrical contact therewith along the length, and preferably along substantially the entire length, of the conductive polymer electrode. The lead body may comprise a multilumen polymer housing, the conductor being contained within one of the lumens of the housing. The conductive polymer electrode may be disposed within a window formed in the lead body. Alternatively, the conductive polymer electrode may comprise multiple electrode sections within a corresponding number of windows formed in the lead body and spaced apart along the length thereof. Further, the window and the conductive polymer electrode disposed therein may extend helically about the lead body. Because of its flexibility and because it can have a small diameter, the lead of the invention is particularly advantageous for implantation in the small, tortuous vessels of the coronary sinus region of the heart for left side stimulation and/or sensing.

Methods of fabricating lead bodies incorporating conductive polymer electrodes are also disclosed.

A patient-worn energy delivery apparatus for imparting electrical therapy to the body of a patient responsive to an occurrence of a treatable condition includes a voltage converter for converting electrical energy from an initial voltage to a final voltage, and a defibrillator electrically coupled between the converter and the patient and having an energy reservoir for receiving the electrical energy. The defibrillator produces preshaped electrical pulses such as defibrillation pulses and cardioversion pulses. The apparatus additionally includes an energy delivery controller electrically coupled to the patient and the converter and the defibrillator. The controller causes the converter to provide the electrical energy to the defibrillator at a specific charging rate in response to an energy level in the reservoir. The apparatus may include a plurality of electrodes interposed between the defibrillator and the patient and each electrode preferably has an impedance reducing means contained therein. One embodiment of the apparatus may include a H-bridge to produce a positive-going pulse segment and the negative-going pulse segment within the biphasic exponential signals. The apparatus periodically measures the energy as it is being delivered to the patient and can pre-emptively stop or truncate the pulse in the event an error condition is detected, such as an overvoltage condition or if the energy level approaches a predetermined level. The electrical components which store and release the energy minimize the size and expense of the apparatus, while isolating the microcomputer from the high energy levels as the therapeutic pulse is delivered.

A cardiac defibrillator includes a fibrillation detector, which determines when a medical patient requires defibrillation at which time a transmitter produces a radio frequency signal. A first stent electrode is implanted into a blood vessel at a first location in the medical patient and a second stent electrode is implanted into a blood vessel at a second location. The first stent electrode contains an electronic circuit that is electrically connected to the second stent electrode. In response to receiving the radio frequency signal, the electronic circuit uses energy from that signal to apply an electric defibrillation pulse between the first and second stent electrodes.

Implantable medical electrical leads having electrodes arranged such that a defibrillation coil electrode and a pace/sense electrode(s) are concurrently positioned substantially over the ventricle when implanted are described. The leads include an elongated lead body having a distal portion and a proximal end, a connector at the proximal end of the lead body, a defibrillation electrode located along the distal portion of the lead body, wherein the defibrillation electrode includes a first segment and a second segment proximal to the first segment by a distance, a first electrical conductor extending from the proximal end of the lead body and electrically coupling to the first segment and the second segment of the defibrillation electrode, and at least one pace/sense electrode located between the first segment and the second segment of the defibrillation electrode.

A system and method for monitoring and controlling the therapy of a cardiac rhythm abnormality victim at a remote site by proving immediate access to a medical professional at a central station. The method comprises the steps of: (1) providing a plurality of electrodes for receiving cardiac signals generated by the victim and for the application of electrical pulses to the victim at a remote site; (2) transmitting the signals from the remote site to a central station; (3) receiving the signals at the central station and displaying them for the medical professional; (4) selecting whether to delivery defibrillation or pacing therapy to the victim based on the medical professional's analysis of the signals (5) transmitting the selection results to the remote site; and (6) receiving the selection results at the remote site and applying the selected therapy to the victim.

A cardiac rhythm management system includes an atrial pacing preference (APP) filter for promoting atrial pacing. The APP filter includes an infinite impulse response (IIR) or other filter that controls the timing of delivery of atrial pacing pulses. The atrial pacing pulses are delivered at an APP-indicated pacing rate that is typically at a small amount above the intrinsic atrial heart rate. For sensed beats, the APP indicated rate is increased until it becomes slightly faster than the intrinsic atrial heart rate. The APP-indicated pacing rate is then gradually decreased to search for the underlying intrinsic atrial heart rate. Then, after a sensed atrial beat, the APP filter again increases the pacing rate until it becomes faster than the intrinsic atrial rate by a small amount. As a result, most atrial heart beats are paced, rather than sensed. This decreases the likelihood of the occurrence of an atrial tachyarrhythima, such as atrial fibrillation. The decreased likelihood of atrial tachyarrhythmia, in turn, decreases the likelihood of inducing a ventricular arrhythmia, either as a result of the atrial tachyarrhythmia, or as the result of delivering a defibrillation shock to treat the atrial tachyarrhythmia.

A health monitoring garment which employs a means of conducting electricity from the surface of the skin, through the fibres of a fabric to another fabric which is removably attached to it and contains a microprocessor, telemetry and a power source to monitor and transmit EKG data of a person wearing the clothing, as illustrated in FIG. 2. Removability enables tile garment to be washed and the electronics to be kept separate from the washing and tumble drying process. The same system can be used in reverse to effect cardiac pacing or defibrillation or to deliver other forms of electronically conveyed healing such as tissue repair.

A leadless intravascular sensor (100, 200) uses the body tissue as a communication medium. The implantable intravascular device has a tubular stent-like structure (102) for intravascular fixation with embedded microcircuits to allow bipolar and unipolar sensing of cardiac and neurologic electrical activity, sensing of other physiologic signals, local electrical stimulation (cardiac pacing and defibrillation; neurologic stimulation and seizure therapy) as well as the ability to communicate with other implanted and non implanted devices via radio frequency and/or optical communication and/or analog signal communication using the body tissue as the conducting medium. The device can also be used in the extravascular or perivascular space. In this form, it has an open/flexible ring that can be adjusted, or self-adjusts to provide no pressure or required contact around the vessel or target region.

A system, apparatus, and method of delivering a defibrillation pulse to the heart of a patient generally includes positioning a pair of electrodes on the exterior surface of the patient's body such that at least one of the electrodes is placed on a limb, e.g., arm or leg, of the patient in a position proximate to the patient's torso. An electrical defibrillation pulse is then delivered through the electrodes, into the limb, enabling the electrical defibrillation pulse to travel from the limb to the heart of the patient.

A cardiac monitor is provided that monitors the condition of the heart of a cardiac patient and generates signals indicating one of several conditions, such as supraventricular tachycardia, ventricular tachycardia and ventricular fibrillation. In order to generate these signals, the ECG from the patient is analyzed to determine a cardiac interval and heart rate, as well as a waveform factor and a waveform factor irregularity. The waveform factor is derived from the average of the ECG amplitudes during a cardiac interval and the peak value of the ECG during the same interval. Preferably, a running average is calculated over several intervals. This waveform factor is then used to detect shockable ventricular arrhythmia. The waveform factor irregularity is indicative of the variability of the waveform factor and is used to differentiate between ventricular tachycardia and ventricular defibrillation.

A resuscitation system for use by a rescuer for resuscitating a patient, comprising at least two high-voltage defibrillation electrodes, a first electrical unit comprising circuitry for providing resuscitation prompts to the rescuer, a second electrical unit separate from the first unit and comprising circuitry for providing defibrillation pulses to the electrodes, and circuitry for providing at least one electrical connection between the first and second units. In another aspect, at least two electrical therapy electrodes adapted to be worn by the patient for extended periods of time, circuitry for monitoring the ECG of the patient, an activity sensor adapted to be worn by the patient and capable of providing an output from which the patient's current activity can be estimated, and at least one processor configured for estimating the patient's current activity by analyzing the output of the activity sensor, analyzing the ECG of the patient, and determining whether electrical therapy should be delivered to the electrodes.

Implantable medical electrical leads having electrodes arranged such that a defibrillation coil electrode and a pace/sense electrode(s) are concurrently positioned substantially over the ventricle when implanted as described. The leads include an elongated lead body having a distal portion and a proximal end, a connector at the proximal end of the lead body, a defibrillation electrode located along the distal portion of the lead body, wherein the defibrillation electrode includes a first electrode segment and a second electrode segment proximal to the first electrode segment by a distance. The leads may include at least one pace/sense electrode, which in some instances, is located between the first defibrillation electrode segment and the second defibrillation electrode segment.

This disclosure describes an implantable medical electrical lead and an ICD system utilizing the lead. The lead includes a lead body defining a proximal end and a distal portion, wherein at least a part of the distal portion of the lead body defines an undulating configuration. The lead includes a defibrillation electrode that includes a plurality of defibrillation electrode segments disposed along the undulating configuration spaced apart from one another by a distance. The lead also includes at least one electrode disposed between adjacent sections of the plurality of defibrillation sections. The at least one electrode is configured to deliver a pacing pulse to the heart and/or sense cardiac electrical activity of the heart.

Cardiac monitoring and/or stimulation methods and systems provide monitoring, diagnosis, and defibrillation and/or pacing therapies. A signal processor receives a plurality of composite signals associated with a plurality of sources, performs a source separation, and produces one or more cardiac signal vectors associated with all or a portion of one or more cardiac activation sequences based on the source separation. A method of signal separation involves detecting a change in a characteristic of the cardiac signal vector relative to a baseline. One or more vectors and/or activation sequences may be selected, and information associated with the vectors and/or activation sequences may be stored and tracked.

An emergency medical kit for use, particularly by a non-professional, to render emergency medical treatment to a patient, includes: a pressurized-oxygen container within a housing; a face mask within the housing for application to the face of a patient requiring cardiopulmonary resuscitation; and a respiratory pump within the housing connected to the pressurized-oxygen container so as to be driven thereby to supply oxygen to the mask for inhalation by the patient, and to discharge the exhalations of the patient via the face mask to the atmosphere. The face mask includes an inflatable seal around its circumference engageable with the face of the patient receiving the mask for sealing the interior of the mask; a pressure sensor sensing the pressure in the inflatable seal; and an indicator for indicating whether the face mask is properly applied to the face of the patient. The kit further includes a neck rest having straps for attaching the face mask thereto in contact with the patient's face when the patient's head is placed on the head rest. According to a most essential aspect of the invention there is provided an emergency, fully automatic kit, based on non-invasive means for performing all stages of the “chain of survival” (including: external defibrillation, ventilation and automatic chest compression) by a single operator.

A method and system (30, 50) for predicting the immediate success of a defibrillatory shock during cardiac arrest are shown. The sequencing of cardiopulmonary resuscitation is determined by an electronic computer (80) based on the probability of success as determined by a comparison of the amplitude spectrum area or the power spectrum area of an electrocardiogram sample and to empirical data. When the probability of successful resuscitation is 80% or greater, immediate defibrillation is implemented. When the probability of success is 20% or less, advanced cardiopulmonary resuscitation is implemented. When the probability of success remains greater than 20% but less than 80% for a period of four minutes, the patient is also defibrillated.

Cardiac monitoring and/or stimulation methods and systems that provide one or more of monitoring, diagnosing, defibrillation, and pacing. Cardiac signal separation is employed to detect, monitor, track and/or trend ischemia using cardiac activation sequence information. Ischemia detection may involve sensing composite cardiac signals using implantable electrodes, and performing a signal separation that produces one or more cardiac activation signal vectors associated with one or more cardiac activation sequences. A change in the signal vector may be detected using subsequent separations. The change may be an elevation or depression of the ST segment of a cardiac cycle or other change indicative of myocardial ischemia, myocardial infarction, or other pathological change. The change may be used to predict, quantify, and/or qualify an event such as an arrhythmia, a myocardial infarction, or other pathologic change. Information associated with the vectors may be stored and used to track the vectors.

Cardiac monitoring and/or stimulation methods and systems provide monitoring, defibrillation and/or pacing therapies. A signal processor receives a plurality of composite signals associated with a plurality of sources, separates a signal using a source separation algorithm, and identifies a cardiac signal using a selected vector. The signal processor may iteratively separate signals from the plurality of composite signals until the cardiac signal is identified. The selected vector may be updated if desired or necessary. A method of signal separation involves detecting a plurality of composite signals at a plurality of locations, separating a signal using source separation, and selecting a vector that provides a cardiac signal. The separation may include a principal component analysis and/or an independent component analysis. Vectors may be selected and updated based on changes of position and/or orientation of implanted components and changes in patient parameters such as patient condition, cardiac signal-to-noise ratio, and disease progression.

A cardiac monitoring and treatment apparatus allows a victim of a medical emergency access to a medical professional (MP) who can monitor, diagnose and treat the victim from a remote site. The apparatus includes a cardiac monitoring and treatment device (CMTD) coupled to an electronic adaptor designed to communicate with a local, first transmitting/receiving (T/R) device which, in turn, is adapted to electronically communicate with a remote, second transmitting/receiving (T/R) device used by the MP. The CMPD comprises a cardiac treatment circuit for effecting cardiac pacing and/or defibrillation and a cardiac signal circuit for receiving cardiac signals. The cardiac signals are (1) transmitted from the signal circuit to the second T/R device for evaluation by the MP, (2) the MP may transmit a control signal to the treatment circuit, and (3), in response thereto, the treatment circuit may generate one or more electrical pulses for treatment of the victim.

Methods for sensing or electrical stimulation of body organs or tissues are disclosed wherein a lead conductor wire or filament of a stranded lead conductor generates a radioactive emission when it is fractured sufficiently or is completely broken. The conductor wire or filament is formed of an inner core and an outer sheath surrounding the inner core, wherein the inner core is irradiated or is formed of a radioactive isotope in an alloy that provides an enhanced radiopaque aura when the sheath is fractured and the inner core is exposed. When the conductor wire or filament is intact, the radioactive inner core is fully encased within the outer sheath, and the outer sheath blocks or reduces radioactive emission along its length to a constant, relatively low level. In use, the emission is detected externally to the body, and the detection signifies that a fracture or break has occurred. Such leads preferably comprise cardiac leads for delivering electrical stimulation to the heart, e.g., pacing pulses and cardioversion/defibrillation shocks, and/or sensing the cardiac electrogram, having multiple lead conductors encased in a lead body subject to fracture under stress. The lead conductors can comprise mono-filar or multi-filar, parallel wound, coiled wires that arranged in a co-axial manner or in a side-by-side arrangement within the lead body. Or the straight or coiled lead conductors can be formed of a strand comprising a plurality of outer filaments wound helically about a central core filament or of a cable comprising a plurality of such peripheral strands wound helically about a central core strand. At least the outer filaments of a stranded conductor and peripheral strands of a conductor cable are formed with the radioactive core.

System and method for monitoring and controlling, defibrillation and pacing which allows a victim of a cardiac rhythm abnormality immediate access to a medical professional at a central station, who will remotely monitor, diagnose and treat the victim at one of a plurality of remote sites in accordance with the following steps: (1) providing a plurality of contact electrodes for a victim at a remote site for the receipt of ECG signals and for the application of electrical pulses to the victim; (2) transmitting the signals from the remote site to a central station and displaying them for review by the medical professional; (3) the medical professional selecting from a menu of defibrillation and pacing pulses, if the application thereof is appropriate; (4) transmitting the selection results to the remote site; and (5) receiving the selection results at the remote site and applying the selected pulses to the victim.

A device capable of providing a user with instructions for administering CPR. This device includes a user input mechanism and a processing unit coupled to the user input mechanism which directs the device to follow one of a first and a second sequence of steps depending on the user's input. In one embodiment, a defibrillator capable of providing a user with instructions for administering defibrillation therapy includes a user input mechanism; a defibrillation therapy delivery circuit; a processing unit coupled to the user input mechanism and the defibrillation therapy delivery circuit which directs the device to follow one of a first and a second sequence of steps depending on the user's input; and an output device coupled to the processing unit for communicating prompts to the user.