159 results about "Ventricular tachycardia" patented technology

Method and apparatus are provided for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue to treat ventricular tachycardia and other arrhythmias while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna (700) is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In operation, microwave energy between about 1 Gigahertz and 12 Gigahertz is applied to monopole microwave radiator (600) having a surface wave limiter (606). A test setup provides physical testing of microwave radiators (854) to determine the temperature profile created in actual heart tissue or ersatz heart tissue (841). Saline solution (872) pumped over the heart tissue (841) with a peristaltic pump (862) simulates blood flow. Optical temperature sensors (838) disposed at various tissue depths within the heart tissue (841) detect the temperature profile without creating any electromagnetic interference. The method may be used to produce a desired temperature profile in other body tissues reachable by catheter (510) such as tumors and the like.

Ventricular tachycardia signals are induced in a living subject. Pace-mapped signals are then obtained from multiple points within the ventricle, and automatically compared numerically with the induced signals. Recognition of a high degree of cross correlation between the induced signals and one or more of the pace-mapped signals identifies arrhythmogenic foci or pathways, which may then be ablated, so that the arrhythmia becomes non-inducible.

A system and method of treating tachycardias and similar syndromes by the use of catheter ablation of tissue is described. A computed tomography (CT)-like image of the heart is obtained and processed to segment the various types of tissue. Papillary muscle areas are identified and displayed differently from the other nearby tissues so that the muscles can be avoided during treatment to avoid or minimize damage to the muscles during ablation treatment. Electrophysical data and scar tissue may also be identified in the image, which may be of the endoscopic type. The position of the catheter may be displayed as a synthetic image on the endoscopic view.

A graphical user interface is provided controllably displaying information retrieved from an implantable device, such as a pacemaker. The graphical user interface is comprised of a first and second window. The first window is adapted to display data identifying a plurality of episodes recorded by the implantable device, wherein the data is comprised of a plurality of fields. One of the fields may be used to identify a type of episode, such as ventricular tachycardia (VT), atrial and ventricular tachycardia (A&V), atrial fibrillation (AF), atrial flutter (Afl), atrial tachycardia (AT), and premature atrial contraction (PAC). The second window is adapted to display data types, such as VT, A&V, AF, Afl, AT, and PAC, that may be present in the plurality of fields, wherein at least one of the data types may be selected to filter the episodes displayed in the first window and display those episodes having the selected data types.

A system and method for classifying cardiac complexes sensed during a tachycardia episode. A first cardiac signal and a second cardiac signal are sensed, where the first cardiac signal has a voltage. A first cardiac complex and a second cardiac complex of a cardiac cycle are detected in the first and second cardiac signal, respectively. A predetermined alignment feature is identified in the second cardiac complex. A datum is defined, or positioned, at a specified interval from the predetermined alignment feature of the second cardiac complex. Voltage values are then measured from the first cardiac complex at each of two or more measurement intervals from the datum. The voltage values are then compared voltage values measured from NSR cardiac complexes to classify the first cardiac complex is either a ventricular tachycardia complex or a supraventricular tachycardiac complex.

An apparatus for mapping and / or ablating tissue includes a braided conductive member that that may be inverted to provide a ring-shaped surface. When a distal tip of the braided conductive member is retracted within the braided conductive member, the lack of a protrusion allows the ring-shaped surface to contact a tissue wall such as a cardiac wall. In an alternative configuration, the braided conductive member may be configured with the distal portion forming a proboscis that can be used to stably position the braided conductive member relative to a blood vessel, such as a ventricular outflow tract. The braided conductive member has a plurality of electronically active sites that may be accessed individually for stable mapping over a broad area for stable mapping or ablation to form broad and deep lesions.

Methods are provided for treating arrhythmias including tachycardias, such as idiopathic ventricular tachycardia, ventricular fibrillation, and Torsade de Pointes (TdP) in a manner that minimizes undesirable side effects.

A method and system for discrimination of supraventricular tachycardia and ventricular tachycardia events. Morphological features points are extracted from normal sinus rhythm (NSR) complexes and used to generate a NSR template. A numerical convolution is performed using the NSR template and the feature points for each sensed NSR to give a NSR filter output. Using a plurality of NSR complexes, a median NSR filter output template is determined, where the median NSR filter output template has a median value for each value in the NSR filter output. The median NSR filter output template is then used during a tachycardia event to distinguish tachycardia events as either ventricular tachycardia events or supraventricular tachycardia events.

A method is provided for analyzing the condition of a patient to determine whether or not a defibrillation shock should be applied, without stopping CPR (primarily chest compressions). While chest compressions continue to be applied to the victim, the system differentiates between (1) a perfusing rhythm that has the capability of leading to a beating heart without a shock and (2) ventricular fibrillation (VF) which sometimes occurs in the presence of ventricular tachycardia (VT), in which there is no capability for leading to a beating heart without a shock. Defibrillation shocks should be applied only when needed and that is in the presence of VF and sometimes in the presence of VT. Electrocardiographic (ECG or EKG) signals obtained from electrodes applied to the patient's chest are analyzed so that the presence of a QRS signal characteristic of a rhythm which has the potential of supporting a beating heart, or the absence of a QRS signal which indicates ventricular fibrillation, may be detected in the presence of artifacts resulting from chest compressions.