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: 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: 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: An apparatus for ablating body tissue, and particularly for creating linear lesions within a chamber of a patient's heart, includes an elongate member having an ablation section. The ablation section includes an infusion tube and a plurality of spaced electrodes. The infusion tube and electrodes are covered by a fluid permeable foam material, and the foam material is covered by a fluid impermeable covering having a plurality of holes formed in it. During use, the ablation section is positioned against tissue to be ablated. Radiofrequency energy is delivered to he electrodes while saline or other conductive fluid is delivered to the infusion tube. The fluid exits the infusion tube at the ablation section, contacts the electrodes, and carries RF energy from the electrodes through the foam, through the holes in the covering and into contact with the body tissue to form a burn in the body tissue.

Abstract: An ablation catheter for ablating tissue, such as endocardial tissue. The ablation catheter includes a foam tip with an electrode embedded therein. Conductive fluid, such as saline solution, is pumped through the foam tip out to the tissue adjacent to the foam tip. The conductive fluid electrically couples the electrode embedded in the foam tip with the tissue to be ablated in order to effect ablation. The flow of the conductive fluid and the foam tip both help prevent any combustible products of the ablation from reaching the high current surfaces of the electrode itself.

Abstract: An apparatus for ablating body tissue is provided that is particularly adapted for creating both linear and point lesions in the endocardium. The apparatus comprises an elongate tubular member having a tip electrode and an ablation section mounted thereon. The ablation section includes one or more spaced electrodes, a fluid permeable foam material, and a fluid impermeable covering having a plurality of holes formed in it. The flow of conductive fluid to the ablation section during use allows contact to be maintained between the electrodes and the tissue to be ablated so as to minimize the formation of lesion breaks. The conductive fluid also serves to cool the tip electrode during its use by delivering the fluid to the tip electrode before routing it to the ablation section. In preferred embodiments, use of a shape wire and/or one or more pullwires allows the inventive apparatus to be more easily manipulated during the ablation procedure.

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: 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: In a shapable catheter and method for positioning a shapable catheter within a body cavity, a core wire is provided which includes a pre-shaped region bent into a predetermined shape. A catheter is provided which includes a lumen proportioned to slidably receive the core wire. The catheter includes a rigid proximal section and a flexible distal section. A pull wire may additionally be provided to allow the user to cause deflection at a distal portion of the catheter.

Abstract: A assembly for use in performing a medical procedure within a region in a body of a patient having a vessel therein comprising a multi-port introducer adapted to be inserted into a vessel of the patient. The multi-port introducer includes an elongate body having proximal and distal extremities and has spaced-apart lumens extending from the proximal extremity toward the distal extremity. The elongate tubular body has ports therein at the proximal extremity in communication with the lumens and openings in the distal extremity in communication with the lumens. The elongate tubular body has a length so that it can extend from the exterior of the body to said region in the body. A plurality of catheters is provided. Each of the catheters is slidably disposed in a separate lumen in the multi-port introducer and has a distal extremity adapted to be disposed in the vessel of the patient.

Abstract: A assembly for use in performing a medical procedure within a region in a body of a patient having a vessel therein comprising a multi-port introducer adapted to be inserted into a vessel of the patient. The multi-port introducer includes an elongate body having proximal and distal extremities and has spaced-apart lumens extending from the proximal extremity toward the distal extremity. The elongate tubular body has ports therein at the proximal extremity in communication with the lumens and openings in the distal extremity in communication with the lumens. The elongate tubular body has a length so that it can extend from the exterior of the body to said region in the body. A plurality of catheters are provided. Each of the catheters is slidably disposed in a separate lumen in the multi-port introducer and has a distal extremity adapted to be disposed in the vessel of the patient.

Abstract: A torquable guiding catheter for use in mapping the wall of a heart of the patient with a mapping catheter having a distal extremity and a mapping device carried by the distal extremity and carrying a plurality of electrodes for engaging the wall of the heart. The basket-like device is movable between expanded and contracted positions and in a contracted position having an outside diameter no greater than a predetermined diameter. The torquable guiding catheter comprises a flexible elongate braided shaft assembly having proximal and distal extremities and having a smooth outer surface and also having a smooth inner surface defining a lumen extending from the proximal extremity to the distal extremity. The flexible elongate braided shaft assembly includes a braid formed of flat metal ribbon extending from the proximal extremity to the distal extremity and having plastic covering the braid having a Shore hardness durometer ranging from 55D to 75D.

Abstract: An apparatus for ablating body tissue, and particularly for creating linear lesions within a chamber of a patient's heart, is provided. The apparatus includes an elongate member having an ablation section which includes an infusion tube and a plurality of spaced electrodes. The infusion tube and electrodes are covered by a fluid permeable foam material, and the foam material is covered by a fluid impermeable covering having a plurality of holes formed in it. During use, the ablation section is placed against tissue to be ablated. This positioning step is facilitated because the ablation section of the inventive devices may be manipulated in various ways. When the ablation section is properly positioned, radio frequency energy is delivered to the electrodes while saline or other conductive fluid is delivered to the infusion tube.

Abstract: In a shapable catheter and method for positioning a shapable catheter within a body cavity, a core wire is provided which includes a pre-shaped region bent into a predetermined shape. A catheter is provided which includes a lumen proportioned to slidably receive the core wire. The catheter includes a rigid proximal section and a flexible distal section. During use, the distal end of the catheter is inserted through a patient's vasculature and is passed into a body cavity. The pre-shaped region of the core wire is passed into the lumen and is straightened by the rigid proximal section of the catheter. The pre-shaped region is passed further into the catheter until it reaches the flexible distal region, in which the pre-shaped section re-assumes its predetermined shape and causes the core wire to form the distal section of the catheter into the predetermined shape.

Abstract: A system for aiding in the positioning of a catheter. The system includes a basket shaped catheter having a plurality of bipoles arranged thereon for sensing voltage potentials generated by tissue. An analog to digital converter is coupled to the catheter and configured to convert the sensed voltage potentials to digital signals. A computer is coupled to the analog to digital converter and to a video display and is programmed to calculate an absolute value of a slope of each of the digital signals. The computer is also programmed to generate and display on the video display a graphical representation of the absolute values of the slopes on a first image corresponding to the catheter. A method of aiding in the positioning of a catheter against a tissue surface is also disclosed.

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.

Abstract: An apparatus for ablating body tissue, and particularly for creating linear lesions within a chamber of a patient's heart, includes an elongate member having an ablation section. The ablation section includes an infusion tube and a plurality of spaced electrodes. The infusion tube and electrodes are covered by a fluid permeable foam material, and the foam material is covered by a fluid impermeable covering having a plurality of holes formed in it. During use, the ablation section is positioned against tissue to be ablated. Radiofrequency energy is delivered to the electrodes while saline or other conductive fluid is delivered to the infusion tube. The fluid exits the infusion tube at the ablation section, contacts the electrodes, and carries RF energy from the electrodes through the foam, through the holes in the covering and into contact with the body tissue to form a burn in the body tissue.