30 results about "Paced Ventricular Rhythm" patented technology

Cardiac monitoring and/or stimulation methods and systems provide for monitoring, diagnosing, defibrillation and pacing therapies, or a combination of these capabilities, including cardiac systems incorporating or cooperating with neuro-stimulating devices, drug pumps, or other therapies. Embodiments of the present invention relate generally to implantable medical devices employing automated cardiac activation sequence monitoring and/or tracking for arrhythmia discrimination. Embodiments of the invention are directed to devices and methods involving sensing a plurality of composite cardiac signals using a plurality of implantable electrodes. A source separation is performed using the sensed plurality of composite cardiac signals and the separation produces one or more cardiac signal vectors associated with one or more cardiac activation sequences that is indicative of ischemia. A change of the one or more cardiac signal vectors is detected using the one or more cardiac signal vectors. Cardiac arrhythmias are discriminated using the one or more cardiac signal vectors.

This invention describes methods and algorithms for processing a plurality of relevant signals/data intrinsic to a patient and/or derived from external diagnostic equipment for management of atrial arrhythmias. The intrinsic signals are acquired from intracardiac leads/sensors and analogous extrinsic data obtained from imaging equipment and patient demographics. These data are input into software algorithms that use digital signal processing to output informational data of clinical and technical relevance after comparisons are made to patients with access to this technology whose outcome under varying treatments is known. These combined data are used to define prognosis, make treatment suggestions, direct programming of cardiac devices and digitally convert intrinsically and extrinsically derived indices into a common metric. In a preferred embodiment, the intrinsically and extrinsically acquired data is utilized in the design of catheters and software algorithms for performing intracardiac procedures such as ablation of atrial arrhythmias.

In a method and implantable medical device for ventricular tachyarrhythmia detection and classification, upon detection of a ventricular tachyarrhythmia based on an electrocardiogram signal, cardiogenic impedance data representative of ventricular volume dynamics are collected and used for classifying the detected tachyarrhythmia as stable or unstable. In the latter case but typically not in the former case, defibrillation shocks or other forms of therapy are applied to combat the unstable ventricular tachyarrhythmia.

Techniques and systems for monitoring cardiac arrhythmias and delivering electrical stimulation therapy using a subcutaneous implantable cardioverter defibrillator (SICD) and a leadless pacing device (LPD) are described. For example, the SICD may detect a tachyarrhythmia within a first electrical signal from a heart and determine, based on the tachyarrhythmia, to deliver anti-tachyarrhythmia shock therapy to the patient to treat the detected arrhythmia. The LPD may receive communication from the SICD requesting the LPD deliver anti-tachycardia pacing to the heart and determine, based on a second electrical signal from the heart sensed by the LPD, whether to deliver anti-tachycardia pacing (ATP) to the heart. In this manner, the SICD and LPD may communicate to coordinate ATP and/or cardioversion/defibrillation therapy. In another example, the LPD may be configured to deliver post-shock pacing after detecting delivery of anti-tachyarrhythmia shock therapy.

Disclosed is a system for the detection of cardiac events (a guardian system) that includes an implanted device called a cardiosaver, a physician's programmer and an external alarm system. The system is designed to provide early detection of cardiac events such as acute myocardial infarction or exercise induced myocardial ischemia caused by an increased heart rate or exertion. The system can also alert the patient with a less urgent alarm if a heart arrhythmia is detected. Using one or more detection algorithms, the cardiosaver can detect a change in the patient's electrogram that is indicative of a cardiac event within five minutes after it occurs and then automatically warn the patient that the event is occurring. To provide this warning, the guardian system includes an internal alarm sub-system (internal alarm means) within the cardiosaver and/or an external alarm system (external alarm means). If the guardian system is put into a pacemaker, the algorithm can utilize a different analysis of the electrogram depending on whether or not the pacemaker is actually pacing the heart.

An electrical method and apparatus for stimulating cardiac cells causing contraction to force hemodynamic output during fibrillation, hemodynamically compromising tachycardia, or asystole. Forcing fields are applied to the heart to give cardiac output on an emergency basis until the arrhythmia ceases or other intervention takes place. The device is used as a stand alone external or internal device, or as a backup to an ICD, atrial defibrillator, or an anti-tachycardia pacemaker. The method and apparatus maintain some cardiac output and not necessarily defibrillation.

An implantable cardiac stimulation device provides accelerated delivery of defibrillation therapy to a patient's heart. The device includes a sensing circuit that provides right and left heart cardiac activity signals and a detector that detects an accelerated arrhythmia of the patient's heart and establishes a plurality of accelerated cardiac rate zones including a fibrillation rate zone and at least one intermediate rate zone. A classifier responsive to the right and left heart cardiac activity signals classifies an accelerated arrhythmia as one of fibrillation and tachycardia responsive to the detector detecting an accelerated arrhythmia having a cardiac rate within the at least one intermediate rate zones. A therapy circuit applies defibrillation to the heart responsive to the classifier classifying an accelerated arrhythmia as fibrillation and anti-tachycardia pacing to the heart responsive to the classifier classifying an accelerated arrhythmia as tachycardia.

A heart stimulator has a stimulation energy delivering assembly, including at least one lead adapted for implantation in contact with cardiac tissue, and an atrial arrhythmia detector, and a control unit connected to the stimulation energy delivering assembly and to the detector. The control unit controls the stimulation energy delivering assembly to deliver at least one atrial arrhythmia abolishing therapy and, if continued atrial arrhythmia is detected, to deliver antithrombus stimulation energy pulses of lower energy than a defibrillation shock, but with different timing and with sufficient energy for producing atrial contraction for increasing hemodynamic blood transportation away from the atrium and for preventing thrombi formation in the atrium. For a patient suffering from a chronic or paroxysmal non-curable atrial arrhythmia, the control unit controls the stimulation energy delivering assembly to deliver the antithrombus energy without any preceding arrhythmia abolishing therapy.

Techniques are described for discriminating ventricular tachycardia (VT) from supraventricular tachycardia (SVT) in circumstances when the ventricular rate exceeds the atrial rate (i.e. V>A). In one example, an initial atrial rate is detected while employing adjustable atrial channel detection parameters that can affect the detection of the true atrial rate—such as a post-ventricular atrial blanking (PVAB) interval or an atrial channel sensitivity level. If the ventricular rate exceeds a VT rate zone threshold with V>A, the device does not immediately deliver high voltage shock therapy as done in other devices. Rather, the device instead selectively adjusts the atrial channel detection parameter(s) to determine if the true atrial rate is equal to the ventricular rate. If so, then such is an indication that the arrhythmia might be SVT rather than VT and various discrimination procedures are employed to distinguish SVT from VT before therapy is delivered.

Techniques are described for discriminating ventricular tachycardia (VT) from supraventricular tachycardia (SVT) using an implantable medical device capable of multi-site ventricular sensing. In one example, ventricular depolarization events are detected within a patient by the implantable device during a tachyarrhythmia, at both a left ventricular sensing site and a right ventricular sensing site. Ventricular event timing differences are then ascertained. The device compares the ventricular event timing differences detected during the tachyarrhythmia with predetermined supraventricular event timing differences for the patient, such as event timing differences previously detected within the patient during sinus rhythm or extrapolated from sinus rhythm values. The device then distinguishes VT from SVT based on the comparison of the event timing differences detected during the tachyarrhythmia with the predetermined supraventricular event timing differences. Morphological waveform analysis can also be performed, when needed, to further distinguish VT from SVT.

A system to measure intracardiac impedance includes implantable electrodes and a medical device. The electrodes sense electrical signals of a heart of a subject. The medical device includes a cardiac signal sensing circuit coupled to the implantable electrodes, an impedance measurement circuit coupled to the same or different implantable electrodes, and a controller circuit coupled to the cardiac signal sensing circuit and the impedance measurement circuit. The cardiac signal sensing circuit provides a sensed cardiac signal. The impedance measurement circuit senses intracardiac impedance between the electrodes to obtain an intracardiac impedance signal. The controller circuit determines cardiac cycles of the subject using the sensed cardiac signal, and detects tachyarrhythmia using cardiac-cycle to cardiac-cycle changes in a plurality of intracardiac impedance parameters obtained from the intracardiac impedance signal.

An implantable cardioverter defibrillator (ICD) and methods of detection and treatment of dangerous and life-threatening heart rhythms by delivering real-time, customized low-energy pacing pulses to specific anatomy in the heart. The ICD includes a power source, a controller, powered by the power source, including an electronic processor, a memory, and a signal generator. The ICD also includes a lead coupled to the controller and an electrode that is in electrical communication with a His-bundle of a patient's heart. The ICD detects a ventricular arrhythmia of the patient's heart using the controller, and is configured to provide a pulsed defibrillation signal to the electrode to terminate the ventricular arrhythmia.

An implantable cardiac stimulation system delivers arrhythmia termination pulses to the ventricles and the atria of a heart. The system includes an implantable cardiac stimulation device, including a conductive enclosure, ventricular arrhythmia termination pulse generator, and an atrial arrhythmia termination pulse generator. A first electrode configuration, including the conductive enclosure, is arranged to be coupled to the ventricular pulse generator to terminate ventricular arrhythmias and a second electrode configuration, electrically independent from the conductive enclosure and confined within the heart, is arranged to be coupled to the atrial pulse generator to terminate atrial arrhythmias.