Abstract: The present invention is a device localization system that uses one or more ultrasound reference catheters to establish a fixed three-dimensional coordinate system within a patient's heart using principles of triangulation. The coordinate system is represented graphically in three-dimensions on a video monitor and aids the clinician in guiding other medical devices, which are provided with ultrasound transducers, through the body to locations at which they are needed to perform clinical procedures. In one embodiment of a system according to the present invention, the system is used in the heart to help the physician guide mapping catheters for measuring electrical activity, and ablation catheters for ablating selected regions of cardiac tissue, to desired locations within the heart.

Abstract: The present invention is a system and method for graphically displaying a three-dimensional model of a region located within a living body. A three-dimensional model of a region of interest is displayed on a graphical display. The location in three-dimensional space of a physical characteristic (e.g. a structure, wall or space) in the region of interest is determined using at least one probe positioned within the living body. The graphical display of the model is deformed to approximately reflect the determined three-dimensional location of the physical characteristic. Preferably, the probe or probes are moved throughout the region of interest so as to gather multiple data points that can be used to increase the conformity between the graphical display and the actual region of interest within the patient.

Abstract: A distance measuring system comprises first and second transducers, and an ultrasound ranging subsystem coupled to the first and second transducers for performing a plurality of distance measurements between the first and second transducers. The distance measurement system can have various applications, including medical applications, in which case, the first and second transducers can be mounted on a catheter. The distance measuring system further comprises a filter coupled to the ultrasound ranging subsystem for filtering ultrasound interference from the plurality of distance measurements (such as, e.g., eight), and outputting a distance based on the filtered distance measurements. The filter filters the ultrasound interference by selecting one of the plurality distance measurements, in which case, the outputted distance is the selected distance measurement.

Abstract: The present invention provides systems, methods, and devices for orienting image data derived from body tissue. An imaging assembly is introduced into the body of a patient and rotated about an axis. A tracking beam mechanically associated with the imaging assembly is generated, such that the tracking rotates about the axis in unison with the imaging assembly. An angle that the rotating tracking beam makes between a reference rotational orientation and a reference point is determined. The reference rotational orientation can be associated with a fiducial point within the ultrasound image data, such that the ultrasound image can be oriented based on the determined tracking beam rotation angle.

Abstract: The present invention provides systems and methods for localizing an ultrasound imaging transducer. The ultrasound imaging transducer is operated in a first resonant mode to transmit an ultrasound imaging signal. Image data is generated based on this transmitted ultrasound imaging signal. The ultrasound imaging transducer is also operated in a second resonant mode to transmit or receive an ultrasound positioning signal. The position of the imaging transducer can then be determined based on the transmitted or received ultrasound positioning signal.

Abstract: A catheter including an elongated body member, an ultrasound transducer located on the elongated body member, and dampening means for forming an ultrasound dampening region adjacent to a portion of the ultrasound transducer, is disclosed. The ultrasound transducer is configured to transmit or receive an ultrasound signal. The ultrasound dampening region is configured to improve uniformity of said ultrasound signal in three-dimensional space. Preferably, the dampening means includes air or a material containing air.

Abstract: A distance measuring system comprises first and second transducers, and an ultrasound ranging subsystem coupled to the first and second transducers for performing a plurality of distance measurements between the first and second transducers. The distance measurement system can have various applications, including medical applications, in which case, the first and second transducers can be mounted on a catheter. The distance measuring system further comprises a filter coupled to the ultrasound ranging subsystem for filtering ultrasound interference from the plurality of distance measurements (such as, e.g., eight), and outputting a distance based on the filtered distance measurements. The filter filters the ultrasound interference by selecting one of the plurality distance measurements, in which case, the outputted distance is the selected distance measurement.

Abstract: The present invention provides systems and methods for locating an imaging device within or outside of the body and for displaying a graphical representation of the imaging pattern associated with the imaging device within a global representation of the body. The imaging pattern characterizes the “field of vision” of the imaging device, and the graphical imaging pattern within the global representation of the body visually indicates the portion of the body that is being imaged by the imaging device in relation to the global representation of the body.

Abstract: The present invention is a device localization system that uses one or more ultrasound reference catheters to establish a fixed three-dimensional coordinate system within a patient's heart using principles of triangulation. The coordinate system is represented graphically in three-dimensions on a video monitor and aids the clinician in guiding other medical devices, which are provided with ultrasound transducers, through the body to locations at which they are needed to perform clinical procedures. In one embodiment of a system according to the present invention, the system is used in the heart to help the physician guide mapping catheters for measuring electrical activity, and ablation catheters for ablating selected regions of cardiac tissue, to desired locations within the heart.

Abstract: The present invention is a device localization system that uses one or more ultrasound reference catheters to establish a fixed three-dimensional coordinate system within a patient's heart using principles of triangulation. The coordinate system is represented graphically in three-dimensions on a video monitor and aids the clinician in guiding other medical devices, which are provided with ultrasound transducers, through the body to locations at which they are needed to perform clinical procedures. In one embodiment of a system according to the present invention, the system is used in the heart to help the physician guide mapping catheters for measuring electrical activity, and ablation catheters for ablating selected regions of cardiac tissue, to desired locations within the heart.

Abstract: A catheter including an elongated body member, an ultrasound transducer located on the elongated body member, and dampening means for forming an ultrasound dampening region adjacent to a portion of the ultrasound transducer, is disclosed. The ultrasound transducer is configured to transmit or receive an ultrasound signal. The ultrasound dampening region is configured to improve uniformity of said ultrasound signal in three-dimensional space. Preferably, the dampening means includes air or a material containing air.

Abstract: A catheter including an elongated body member, an ultrasound transducer located on the elongated body member, and dampening means for forming an ultrasound dampening region adjacent to a portion of the ultrasound transducer, is disclosed. The ultrasound transducer is configured to transmit or receive an ultrasound signal. The ultrasound dampening region is configured to improve uniformity of said ultrasound signal in three-dimensional space. Preferably, the dampening means includes air or a material containing air.

Abstract: An ablative catheter assembly whose electrode is completely covered by a buffer layer. The buffer layer prevents areas of high current density at the surface of the catheter tip, which helps to reduce popping and clotting. The buffer layer may be in the form of a conductive fluid (such as saline solution) pumped into a cavity surrounding the electrode. In this case, the conductive fluid couples the electrode to the surrounding tissue so that RF energy will pass from the electrode to the tissue, thereby effecting ablation. Also, the buffer layer may be in the form of a porous coating which covers an electrode tip. In this case, blood or fluid which infuses the porous coating couples the electrode tip to the surrounding tissues to be ablated.

Abstract: The present invention is a device localization system that uses one or more ultrasound reference catheters to establish a fixed three-dimensional coordinate system within a patient's heart using principles of triangulation. The coordinate system is represented graphically in three-dimensions on a video monitor and aids the clinician in guiding other medical devices, which are provided with ultrasound transducers, through the body to locations at which they are needed to perform clinical procedures. In one embodiment of a system according to the present invention, the system is used in the heart to help the physician guide mapping catheters for measuring electrical activity, and ablation catheters for ablating selected regions of cardiac tissue, to desired locations within the heart.

Abstract: A catheter device for creating linear lesions in endocardial tissue or other body tissue is described. The catheter includes an inner shaft telescopically received within an outer shaft. The inner shaft has one or more spaced apart electrodes along its distal section. The outer shaft member includes a fluid permeable window positionable to selectively overlay some or all of the electrodes when the relative positioning of the inner and outer shaft members is adjusted. During use, the window is positioned adjacent to the body tissue which is to be ablated and at least a portion of the electrodes are exposed through the window. RF energy is delivered to the electrodes while saline or other conductive fluid is simultaneously delivered through the infusion tube.

Abstract: Endocardial system and method in which noise and artifacts introduced by a simulator are decoupled from a recorder by connecting the stimulator to the electrodes used for pacing and recording only when it is necessary to do so. At other times, the stimulator is disconnected, and low level signals are recorded without interference from the stimulator. In one embodiment, the stimulator is connected only during the time the pacing pulse is being delivered. In another, a stimulator which delivers pacing pulses in response to intrinsic activation of tissue at the pacing site is connected during delivery of a pacing pulse, disconnected during the measurement period which follows, and then reconnected so that it can sense further intrinsic activity and deliver another pacing pulse.