Abstract: A stiffenable balloon catheter assembly capable of being converted from an “over-the-wire” mode with respect to a guidewire extending therethrough to a “rapid-exchange” mode with respect to a guidewire extending therethrough, and vice versa. The catheter has a plurality of lumens, one lumen however, having a side opening with an obstructable galp, the orientation of which, determines the utilization “mode” of the catheter assembly. Stiffening stylets may be adjustably locked into the lumens, depending upon the “mode”, to control the stiffness of the catheter assembly during its utilization within a patient.

Abstract: A stiffenable balloon catheter assembly capable of being converted from an “over-the-wire” mode with respect to a guidewire extending therethrough to a “rapid-exchange” mode with respect to a guidewire extending therethrough, and vice versa. The catheter has a plurality of lumens, one lumen however, having a side opening with an obstructable galp, the orientation of which, determines the utilization “mode” of the catheter assembly. Stiffening stylets may be adjustably locked into the lumens, depending upon the “mode”, to control the stiffness of the catheter assembly during its utilization within a patient.

Abstract: A stiffenable balloon catheter assembly capable of being converted from an “over-the-wire” mode with respect to a guidewire extending therethrough to a “rapid-exchange” mode with respect to a guidewire extending therethrough, and vice versa. The catheter has a plurality of lumens, one lumen however, having a side opening with an obstructable galp, the orientation of which, determines the utilization “mode” of the catheter assembly. Stiffening stylets may be adjustably locked into the lumens, depending upon the “mode”, to control the stiffness of the catheter assembly during its utilization within a patient.

Abstract: An electro-surgical device for performing tissue resection and cauterization includes an elongated body, a pair of arms extending from a distal end of the elongated body, and an electrode in communication with the pair of arms. The elongated body is adapted to be coupled to a source of energy at a proximal end. The electrode has a first region coated with an insulative coating and a second region for focusing energy emission. The coating can be a diamond-like carbon coating or other coating exhibiting resistance to cracking at high temperatures and high voltages. The coating can be deposited on a base section of a loop electrode while the end sections remain free of the coating. Alternatively, the coating can be unevenly deposited on the electrode. In other embodiments, the electrode can comprise a rollerball and the insulative coating can be deposited on selected or random portions of the rollerball.

Abstract: Wires are used for conducting ultrasound energy. These wires achieve optimum properties by creating a multiple material coaxial construction. For example, in a particular embodiment it is desirable to have an elastic core (nitinol) for conducting axial vibrations (sonic or ultrasonic) and a thin stiff cladding (stainless steel) in order to minimize traverse vibrations which result in loss of energy.

Abstract: An expansible balloon catheter has at least a first exterior surface with a given coefficient of friction and a second exterior surface with a greater coefficient of friction. In a compact form only the first exterior surface is exposed to produce one coefficient of friction during transfer of the collapsed or uninflated balloon to and across a lesion. When inflated, the second surface dominates the first surface and produces a second coefficient of friction.

Abstract: An acoustic imaging system for use within a heart has a catheter (6), an ultrasound device (10) incorporated into the catheter (6), and an electrode (300, 304, 334, 394) mounted on the catheter (6). The ultrasound device (10) directs ultrasonic signals toward an internal structure in the heart to create an ultrasonic image, and the electrode (300, 304, 334, 394) is arranged for electrical contact with the internal structure. A chemical ablation device (55, 86, 314, 396) mounted on the catheter (6) ablates at least a portion of the internal structure by delivery of fluid to the internal structure. The ablation device (55) may include a material that vibrates in response to electrical excitation, the ablation being at least assisted by vibration of the material. The ablation device may alternatively be a transducer (414) incorporated into the catheter (6), arranged to convert electrical signals into radiation and to direct the radiation toward the internal structure.

Abstract: An expandable ablation electrode is provided on a catheter constructed to access the heart. When the electrode is introduced to the heart, it is small and suitably flexible to maneuver through the torturous path. However, when the catheter is in place in the heart, the electrode is expansible in diameter to a substantially larger dimension, and is relatively rigid, enabling a large conductive surface to press against the heart tissue with the desired contact pressure. When RF energy is then applied to the electrode it produces a burn lesion of desired large size and depth. This overcomes the limitations to size that have been encountered using conventional rigid electrodes.

Abstract: An expansible balloon catheter with a stent thereon has at least a first exterior surface with a given coefficient of friction and a second exterior surface with a different coefficient of friction. In a compact form only the first exterior surface is exposed to produce one coefficient of friction during transfer of the collapsed or uninflated balloon and stent to and across a lesion. When inflated, the second surface dominates the first surface and produces a second coefficient of friction.

Abstract: A catheter for insertion into a bodily conduit, especially an artery. The catheter comprises a shaft (26) having at least one lumen (24) for delivery of a fluid inflation media and a double balloon (12) including an array (20) of a plurality of inflatable secondary chambers (22) radially disposed in a cylindrical array around an inflatable primary chamber (16). Each of the secondary chambers (22) shares a common wall (38) with adjacent secondary chambers (22) and a common wall (14) with the primary chamber (16). The secondary chambers (22) are inflated by an array of channels (32) which are separated from each other by webs (40). One or more of the secondary chambers (22) may be in communication with a pressure transducer for measurement of the resistance of, e.g., a stenosis to dilation by the balloon (12). Alternately, a triple balloon (60) has inner secondary chambers (22a) and outer secondary chambers (22b).

Abstract: An expansible balloon catheter has at least a first exterior surface with a given coefficient of friction and a second exterior surface with a greater coefficient of friction. In a compact form only the first exterior surface is exposed to produce a low coefficient of friction during transfer of the collapsed or uninflated balloon to and across a lesion. When inflated, the second surface dominates the first surface and produces an increased coefficient of friction overall thereby to stabilize the balloon in the lesion.

Abstract: Systems and methods for dilation of a body lumen, using an expandable dilatation catheter to simultaneously heat and apply pressure to tissue of the lumen and to expand and dilate the lumen including means constructed to produce and/or detect physiological response of the heated tissue to applied pressure.

Abstract: A calibrated guidewire for use in determining the magnitude of arterial occlusions in the body and a method of using the guidewire. The guidewire includes a flexible sleeve having a distal end and a hemispherical tip having a flat inner surface. A multifilar flexible coil is disposed between the distal end of the sleeve and the tip. The coil has a uniform outer diameter and is formed by two sets of different wires, one of which is radiotransparent and the other of which is radiopaque. The spacings between each of the sets is identical and is defined by the widths of each of the sets to provide regularly spaced radiotransparent areas of indicia that are observable as a fluoroscopic image to enable the user measure of the magnitude of an occlusion in a tubular structure in the body. The multifilar construction extends the entire length of the coil between the sleeve and the tip.

Abstract: A catheter includes a flexible elongated catheter body that defines a needle-receiving, or probe-receiving, lumen, a retractable tissue-penetrable needle, or probe, and an electrode mounted on the distal portion of the catheter body. The needle provides a fluid passage for introducing fluid into tissue to permit the introduction of sclerotic agents for enhancing electrocoagulation of the tissue, heat-responsive drugs for improving the bonding to tissue surfaces, or vaso-constrictor drugs. The probe can also have a passage for fluid. The electrode can provide bipolar electro-coagulation of tissue in combination with an additional electrode mounted on the catheter body, or alternatively, the electrode can be employed in combination with either the needle or probe to establish a bipolar electro-coagulation path through tissue. The needle, or probe, in combination with an external electrode can be used to provide unipolar electro-coagulation, or ablation.

Abstract: A steerable guidewire for gently penetrating an occlusion within a vessel, with an elongated solid main guidewire body having selected stiffness characteristics along its length to allow the guidewire to be urged through a narrow, tortuous body lumen by application of forces at a proximal end, and an enlarged distal end portion having a diameter larger than portions of the guidewire proximal thereof including a soft polymeric element and a permanently deflected portion to enable steering of the guidewire.

Abstract: Acoustic imaging balloon catheters formed by a disposable liquid-confining sheath supporting a high fidelity, flexible drive shaft which carries on its end an ultrasound transducer and includes an inflatable dilatation balloon. The shaft and transducer rotate with sufficient speed and fidelity to produce real time images on a T.V. screen. In preferred embodiments, special features that contribute to the high fidelity of the drive shaft include the particular multi-filar construction of concentric, oppositely wound, interfering coils, a pre-loaded torque condition on the coils enhancing their interfering contact, and dynamic loading of the distal end of the probe, preferably with viscous drag. The coil rotating in the presence of liquid in the sheath is used to produce a desirable pressure in the region of the transducer.

Abstract: A guidewire for penetrating an occlusion within a duct or vessel, such as a blood vessel, has an elongated main guidewire body of a small, first diameter. The guidewire is terminated at its distal end with an enlarged resilient tip portion having a lubricious outer surface, and is shaped and constructed to penetrate the occlusion. The guidewire body is constructed to be to be relatively flexible in the distal end corresponding to the enlarged tip and relatively stiffer in portions proximal thereof for manipulation of the wire from its proximal end to cause the distal tip portion to penetrate the occlusion and form a passage therein. In an embodiment, an outer sleeve is slid over the main body and butting against the proximal end of the enlarged tip portion contributes to axial stiffness of the combination to enable manipulation through the occlusion. After placement this sleeve is removed and a dilatation catheter is slid over the main body, and enters the occlusion behind the enlarged tip portion.

Abstract: A surgical instrument useful for laparoscopic surgery comprising an insulated shaft, a control means and a connection to an electrosurgical radiofrequency power source, its distal end being of general J-hook form having a tissue-engaging ledge, and the shaft supporting a tissue-engaging clamping or cutting member movable toward the ledge in response to the control means so that an artery or other tissue in the pocket of the J-hook can be clamped or cut while radiofrequency current is applied. Instrument constructions disclosed incorporate one or two clamping members and a cutting member arranged such that with actuation, the clamping member(s) engages the ledge before the cutting member, and, by selective actuation of the electrosurgical power source, coagulation current can be applied while clamping an artery or other tissue against the ledge to stop flow of blood, and by further actuation of the control and suitable current to the cutting member, the artery or tissue may be cut.

Abstract: A catheter device and method for heating tissue, the device having a catheter shaft constructed for insertion into a patient's body, and at least one chamber mounted on the catheter shaft. The catheter shaft has at least one lumen for fluid flow through the shaft. The chambers are defined by walls that are at least in part expandable. Fluid flows, through the lumens, between the chambers and a fluid source outside the body. The chambers can be filled with the fluid after they have been placed within the body. A heating device heats liquid within at least one of the chambers, so that heat is transmitted from the liquid to surrounding tissue by thermal conduction through the wall of the chamber. Means are provided for selectively directing heat transmission toward a selected portion of surrounding tissue. The chambers are fillable with fluid separately from each other, so that the chambers can occupy any of a plurality of possible total volumes.

Abstract: Device and method for treating tissue inside a patient's body, the device including an endoscopically introducible catheter shaft. The endoscope is constructed for insertion into the patient's body, and has a channel passing through it. The channel terminates at an opening in the distal end of the endoscope. The channel enables the catheter shaft to pass through the endoscope and beyond the distal end of the endoscope. A chamber is mounted on the catheter shaft. The chamber is defined by a flexible wall. The chamber is associated with a first lumen defined by the catheter for fluid flow between the chamber and a fluid source outside of the patient's body. The chamber is fillable with fluid after placement in the patient's body. When the chamber is filled with fluid it has a diameter greater than the diameter of the transverse cross-section of the endoscope channel.