Abstract: Therapeutic device intended for the selective cytoreductive treatment of an obstruction in a natural lumen or passage of the human or animal body, said lumen being obstructed by the effect of a local cell proliferation, said device comprising a tubular element, in particular of cylindrical shape, intended to be placed in said natural lumen and sufficiently flexible to conform to said natural lumen, but sufficiently rigid to maintain an artificial channel in said lumen. The tubular element supports lengthwise a medicinal sleeve which is intended to come into line with, and into contact with, the obstruction once the natural lumen has been intubated, and is designed to deliver locally, at least in its outer surface portion, at least one therapeutic agent which is cytoreductive, in particular cytotoxic, through contact with the cells under whose effect said lumen is obstructed.

Abstract: Systems and methods for gaining percutaneous access to a body lumen, preferably without a guidewire, are provided herein. The system can include a tubular medical device and a needle with a distal tip. A side port is provided through a wall of the tubular medical device, to be in communication with a distal end opening of the device via a passageway. The needle can be positioned within the side port to extend the distal tip beyond the distal end opening. In this position, the distal tip can form an entry opening in the body lumen, and a distal portion of the device can be advanced over the indwelling needle into the entry opening. The needle can then be withdrawn from the tubular medical device, while maintaining a portion of the tubular medical device in place within the body lumen.

Abstract: A therapeutic agent delivery system that includes a catheter having a proximal end and an opposite distal end. The catheter has a body with a lumen defined therein. The body of the catheter includes a non-bulbous region having a substantially uniform outer diameter and a bulbous region made from an elastically deformable material. While in a first state the bulbous region has a maximum outer diameter greater than the substantially uniform outer diameter of the non-bulbous region; and while in a second state the maximum outer diameter of the bulbous region is reduced relative to that while in the first state.

Abstract: An introducer sheath includes a tubular body portion having a proximal region and a distal region, and defines an internal lumen configured and dimensioned to slidably receive a catheter. A penetrating portion at a distal end of the tubular body has a first tapered configuration to enlarge an opening in a body tissue during distal advancement of the introducer sheath through the body tissue and a second expanded configuration to enable the passage of a distal end portion of a catheter through the penetrating portion.

Abstract: Some embodiments of a medical device anchor system include an anchor sleeve that receives a catheter (or other medical instrument) though a working channel of the anchor sleeve. The anchor sleeve may include a first actuator that controls the extension of one or more subcutaneous tines into the subcutaneous region under the skin. The anchor sleeve can also include a second actuator that can cause the anchor sleeve to lock onto an outer portion of the catheter (or other medical instrument) arrange in the working channel.

Abstract: Some embodiments of a medical anchor device include an elongate body coupled with deployable subcutaneous anchors to secure a catheter instrument (or other medical instrument) in place relative to a skin penetration point. In some circumstances, the elongate body may be in the form of catheter hub body, and the subcutaneous anchors can be deployed from the hub body by adjustment of a movable actuator. A locking member can interact with the actuator so as to retain the actuator in the deployed orientation during the medical procedure.

Abstract: An introducer assembly includes a sheath and a dilator. A biodegradable shroud covers the distal portion of the introducer assembly on the surface of both the sheath and the dilator. The biodegradable shroud dissolves in blood after being exposed for a predetermined time. Afterwards, the dilator can be separated from the sheath without breaking the sheath. The shroud improves movement of the introducer assembly through a venous system by preventing body tissue from getting caught in the space between the dilator and the shroud, for example should a “fish mouth” separation occur between them.

Abstract: An access device places a medical article within a body space of a patient. The device has a needle that includes an elongated body and a needle hub. The device further includes a dilator disposed on and slideable along the elongated body of the needle and a medical article. The medical article is disposed on and slideable along the dilator. A track extends in a proximal direction from the dilator. The needle hub slides along at least a portion of the track between a first position and a second position. The device further includes a locking mechanism operably disposed between the track and the needle hub so as to inhibit further axial movement of the needle in the proximal direction when the needle hub is in the second position.

Abstract: A surgical access device for surgical instruments comprises a housing with an instrument port and zero closure valve. A cannula is disposed distally relative the housing. The cannula comprises a distal end, a proximal end, and a flexible tube having a longitudinal axis between the distal and proximal ends. An instrument seal is positioned adjacent the distal end of the cannula. The instrument seal is dimensioned to have an interference fit with a surgical instrument inserted into the cannula. Longitudinal movements of a surgical instrument are accommodated by buckling of the flexible tube while the relative longitudinal position of the instrument seal and instrument are substantially unchanged.

Abstract: A stabilization seal is used with existing cannulas for forming a gas-tight seal with tissue in a body wall. The stabilization seal includes a cylindrical inflatable elongate tube having a graduated wall-thickness that is thicker in a central region and thinner in a distal-end region. The tube includes a sealing cuff, having an inflation port, for sealing around a cannula. Application of inflation pressure greatly expands the distal-end region while the central region expands slightly. Another embodiment of a stabilization seal includes an inflatable thread that is used with a cannula having a helical channel on its outer surface. An inflatable tube is wound into the channel. A distal end of the tube includes a gas-tight seal and a proximal end of the tube includes an inflation port. In the uninflated condition the nested tube is flush with the channel. Inflating the tube enlarges the cannula assembly.

Abstract: Apparatus and methods are provided for providing access to a body lumen, e.g., to deliver a pacing lead within a patient's heart. The apparatus includes a tubular member including a proximal end, a distal end sized for insertion into a body lumen, and a lumen extending therebetween. An elongate member extends from the distal end of the tubular member. An expandable sheath extends along at least a portion of the elongate member, the sheath being expandable from a contracted condition to facilitate insertion into a body lumen, and an enlarged condition wherein the sheath at least partially defines a lumen communicating with the tubular member lumen. A stylet or other shaped element is insertable into the elongate member for changing a shape of at least a distal tip of the elongate member, e.g., for accessing side branches extending from a body lumen, e.g., within a patient's coronary venous system.

Abstract: Some embodiments of a medical anchor device include an elongate body coupled with deployable subcutaneous anchors to secure a catheter instrument (or other medical instrument) in place relative to a skin penetration point. In some circumstances, the elongate body may be in the form of catheter hub body, and the subcutaneous anchors can be deployed from the hub body by adjustment of a movable actuator. A locking member can interact with the actuator so as to retain the actuator in the deployed orientation during the medical procedure.

Abstract: Systems, kits, and methods for establishing percutaneous access are described. A system typically includes a deformable variable diameter cannula sleeve (DVDCS) and a guidewire. The DVDCS will generally have two states, an initial, un-activated condition and a second, activated condition, brought about and controlled under the discretion of the operator. The methods comprise creating an initial access point and tissue tract with a needle, positioning a guidewire through the initial tissue tract, passing the deformable variable diameter cannula sleeve over the guidewire through the tissue tract to a target blood vessel or cavity, and activating the DVDCS to effect radial deformation of the surrounding tissue. Use of the DVDCS reduces the risk of injuring tissue surrounding the tissue tract by lessening the axial forces imparted to the tissue. Kits comprise at least one deformable variable diameter cannula sleeve together with instructions for use.

Abstract: A medical instrument has a cannula, a seal disposed in said cannula, said seal has an opening for guiding a shaft of another instrument through said seal in a sealed manner. An expansion device serves for expanding said opening in said seal. Said expansion device has an expansion cone comprising a plurality of slats mounted pivotably on an annular body at a first end, a second end of said slots opposite to said first end being connected to said seal in an area of said opening. A flexible casing structure is provided accommodating said seal and said expansion device.

Abstract: An access device places a medical article within a body space of a patient. The device has a needle that includes an elongated body, a side fenestration on the elongated body, and a needle hub. The device further includes a dilator disposed on and slideable along the elongated body of the needle and a medical article. The medical article is disposed on and slideable along the dilator. The dilator and the needle form one or more spaces in communication with the side fenestration. At least portions of the dilator and the medical article are configured so as to allow visual determination of the presence of a bodily fluid within the space. The outer surface of the needle and the inner surface of the dilator can include a surfactant. Further, at least one of the needle and dilator can further comprise a vent in communication with the space that allows for the escape of air from the space and inhibits the escape of the bodily fluid from the space.

Abstract: A support catheter that can puncture a heart septum with a guidewire without buckling and that can access difficult to reach arteries such as carotid or renal arteries from the aorta under difficult circumstances is provided. The support catheter comprises a catheter body having a proximal end, a distal end, and an interior wall surface defining a first lumen extending from the proximal end toward the distal end. A second lumen is disposed between the interior wall surface and an outer surface of the catheter body. A plurality of stiffening members is disposed around the second lumen, the plurality of stiffening members being engageable to selectively stiffen the catheter body. In another configuration, the catheter further comprises a second plurality of stiffening members disposed between the first lumen and the second lumen.

Abstract: An access needle well-suited for percutaneous implantation in a body lumen, such as the stomach or the jejunum. In one embodiment, the access needle comprises a cannula, a needle, a retractable stopper and a spreader. The cannula is a tubular member having a lumen and a pair of side windows providing access to the lumen. The needle is slidably mounted within the cannula lumen and comprises a needle stem and a needle handle, the needle handle extending outwardly from the needle stem proximate to the proximal end thereof. The stopper is coupled to the needle stem for translational movement, the stopper comprising a pair of outwardly-biasing wings removably insertable through the side windows for engaging an interior surface of a patient. The spreader is mounted within the cannula and spreads the wings outwardly as the wings are inserted out the side windows.

Abstract: Access devices and related methods are disclosed that generally involve flexible or adjustable cannulas that have a substantially cylindrical insertion configuration and a substantially conical expanded configuration. Various methods and features are provided for transitioning the cannula from the insertion configuration to the expanded configuration while the access device is inserted through tissue to form a conical opening through the tissue. Examples include cables, biasing elements, retaining elements, bimodal rings, and coil springs. The devices and methods disclosed herein can allow for improved retention of the access device, improved angulation of instruments passed through the access device, and can increase the integrity of a seal formed between the access device and surrounding tissue.

Abstract: An assembly for accessing a vessel comprises an elongate housing having a longitudinal axis, a proximal end, and a distal end opposite the proximal end. The housing includes a base extending from the proximal end, an elongated tubular extending from the distal end to the base, and a throughbore extending axially from the proximal end to the distal end. In addition, the assembly comprises a stylet extending axially through the throughbore of the housing. The stylet has a proximal end comprising an actuation head external the throughbore of the housing, and a distal end opposite the proximal end of the stylet. Further, the assembly comprises an expandable member coupled to the distal end of the housing or the distal end of the stylet. The expandable member has an expanded position with a first diameter and an unexpanded position with a second diameter that is less than the first diameter.

Abstract: The disclosure relates to an a catheter sheath introducer that is capable of being expanded from first diameter to second diameter in order to accommodate differently sized medical devices to be introduced by the sheath introducer. The device is structured such that it does not foreshorten when expanded.

Abstract: A low profile surgical access device includes an elongated cannula having an opening defined at a proximal end thereof including an inner peripheral surface dimensioned to facilitate passage of instrumentation therethrough and an outer peripheral surface configured to operatively engage and removably secure to tissue via, e.g., fixation ribs, adhesive, anchors, clips, suction elements, expandable materials and/or combinations thereof. A valve is operatively coupled to the elongated cannula and provides a substantially fluid tight seal when instrumentation is inserted through the cannula. A seal housing is included which is positionable relative to the cannula and which is configured to operatively engage and removably secure to tissue. The instrument seal in the seal housing is positioned in vertical registry with the valve in the elongated cannula.

Abstract: The disclosure is directed to a needle system configured to enlarge an access path in a patient without further cutting into the tissue of the patient so as to reduce recovery time and trauma to the patient. Also provided are methods of using the needle system provided.

Abstract: A device may include a hollow needle, a dilator mounted coaxially on the needle, and a sheath mounted coaxially on the dilator. The dilator may be slideably displaceable relative to the sheath.

Abstract: Laparoscopic instruments and cannulas are provided for performing laparoscopic procedures entirely through the umbilicus. Generally S-shaped laparoscopic instruments placed through the C-shaped trocar sleeves or through the cannula and instrument holder unit provide markedly improved degrees of instruments' freedom during trans-umbilical laparoscopic procedures.

Abstract: Various devices and methods are provided for dilating tissue. In one embodiment, a trocar cannula is provided and includes an elongate tubular member defining an inner lumen extending therethrough and configured to receive a surgical instrument therethrough. The tubular member is configured to radially expand to increase an inner diameter of the inner lumen and thereby dilate tissue. In one embodiment, the tubular member has an expansion element incorporated therein and the expansion element is configured to maintain the tubular member in a radially expanded position when no instrument is disposed within the inner lumen.

Abstract: Apparatus and methods for providing access to a body cavity without substantial loss of inflation gas therein. The apparatus includes an access assembly that has a tubular member having a proximal end, a distal end, an elastic portion interposed the proximal end and the distal end, and a lumen therethrough. An anchor sleeve is disposed coaxially over the tubular member and has a radially expandable region. The anchor sleeve is moveable between an axially elongated configuration and an axially shortened configuration and is biased toward the axially shortened configuration by a force exerted by the elastic portion of the tubular member. The axially shortened configuration corresponds to the anchor sleeve being in the fully deployed position. Methods for providing anchored access to a cavity within a patient are also disclosed.

Abstract: A device is provided for performing intra myocardial injections. The device comprises a needle, a catheter formed with a lumen, and an abutment member mounted within the lumen for axial movement. The abutment member is movable between a first configuration, wherein it is substantially tube-like and is positioned within the lumen of the catheter, and a second configuration, wherein it extends beyond the distal end of the catheter and is substantially radially flared. Before the needle is advanced to perform an injection, the abutment member is moved to its second configuration to prevent contact between the catheter and the myocardial tissue during the injection.

Abstract: A method for forestalling or therapy, at least partially, of BPH or prostate cancer comprising identifying a reflux of venous blood to the prostate and impeding the reflux by treating veins effecting or conveying the reflux, and related apparatus and kit.

Abstract: A safety trocar assembly incorporating an airbag is provided to prevent overpenetration of the safety trocar assembly through an abdominal wall and into a body cavity. The safety trocar assembly includes an airbag cannula having an expandable airbag proximal of the distal end of the cannula. A sensing device is located at a distal end of the cannula for detecting changes in conditions at the distal end of the cannula. A trigger mechanism is provided on the cannula and operates to inflate the airbag in response to a change in condition detected by the sensing device.

Abstract: An introducer sheath and methods of making the introducer sheath are described. The introducer sheath may include a hub portion and a tubular portion. The tubular portion may extend from the hub portion. A lumen may extend between a proximal end and a distal end of the tubular portion. At least a portion of an inner surface and/or outer surface of the tubular member may be irregular.

Abstract: Disclosed is an expandable transluminal sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion of at least a part of the distal end of the sheath to a second, enlarged cross-sectional configuration. The sheath is configured for use in the vascular system and has utility in the introduction and removal of balloon counterpulsation catheters. The access route is through the femoral arteries and the iliac arteries into the aorta, where an intra-aortic balloon pump catheter is positioned to provide cardiac support. The distal end of the sheath is maintained in the first, low cross-sectional configuration during advancement to the arteries into the aorta. The distal end of the sheath is subsequently expanded using a radial dilatation device.

Abstract: The purpose of this invention is to provide an esophagus stoma button capable of safely forming and maintaining a stoma hole provided in an esophagus and reducing the discomfortableness of a patient. To achieve the object, in the present invention, the stoma button 9 is comprised of a shaft part 1 and a flange part 2 provide at the rear end of the shaft part rounded at the tip thereof. More specifically, in the esophagus stoma button 9, a flange part is provide at the rear end of the shaft part rounded at the tip thereof, and a lumen having a generally circular cross section in the area ranging from the shaft part to the flange part is provided, a means for fixing a catheter for infusion is provided in the flange part with a flat and generally circular shape and a means for tightly closing the opening of the flange part is provided at the opening thereof.

Abstract: In at least one embodiment of the present invention, an introducer for use in inserting a medical device into a body vessel of a patient is provided. The introducer comprises a housing having a proximal opening, a distal opening and a chamber extending therebetween. A seal in diaphragm form is disposed in the chamber. The seal is formed of polymeric material having a first phase transition temperature higher than about body temperature and a second phase transition temperature that is less than the first phase transition temperature but is greater than about room temperature. The seal is in a first configuration and has an opening formed therethrough when at about room temperature for advancing the medical device through the seal. The seal self-configures to a second configuration when at a temperature of at least the second phase transition temperature for obstructing the body fluid from flowing through the opening of the seal.

Abstract: A medical instrument has a cannula, a seal disposed in said cannula, said seal has an opening for guiding a shaft of another instrument through said seal in a sealed manner. An expansion device serves for expanding said opening in said seal. Said expansion device has an expansion cone comprising a plurality of slats mounted pivotably on an annular body at a first end, a second end of said slots opposite to said first end being connected to said seal in an area of said opening. A flexible casing structure is provided accommodating said seal and said expansion device.

Abstract: A catheter connector system for a subcutaneously placed catheter. The catheter connector system permits proximal trimming of the placed catheter, which is a procedure that provides numerous advantages over traditional methods of trimming catheter distal ends prior to implantation. The catheter connector system can be configured for a single lumen catheter or a multiple lumen catheter. The catheter connector system facilitates precise positioning of both distal and proximal ends of a catheter, providing enhanced functionability and patient comfort.

Abstract: Systems, kits, and methods for establishing percutaneous access are described. A system typically includes a deformable variable diameter cannula sleeve (DVDCS) and a guidewire. The DVDCS will generally have two states, an initial, un-activated condition and a second, activated condition, brought about and controlled under the discretion of the operator. The methods comprise creating an initial access point and tissue tract with a needle, positioning a guidewire through the initial tissue tract, passing the deformable variable diameter cannula sleeve over the guidewire through the tissue tract to a target blood vessel or cavity, and activating the DVDCS to effect radial deformation of the surrounding tissue. Use of the DVDCS reduces the risk of injuring tissue surrounding the tissue tract by lessening the axial forces imparted to the tissue. Kits comprise at least one deformable variable diameter cannula sleeve together with instructions for use.

Abstract: A guide wire includes a distal end side portion formed of a first metallic material, a proximal end side portion formed of a second metallic material higher in rigidity than the first metallic material, and an intermediate portion provided between the distal end side portion and the proximal end side portion and formed of a mixture of the first metallic material and the second metallic material. The intermediate portion includes a gradient physical property portion in which the content of the second metallic material increases from the distal end side toward the proximal end side.

Abstract: The invention comprises an atherectomy probe for mechanically cutting core prostatic tissue to alleviate the condition of benign prostatic hyperplasia (BPH) or for use in orthopedic procedures. The blade shapes and lengths are adaptable but in a preferred embodiment the device includes an end-cutting bur tip. The cutting motion may be one of: guillotine (incising between two parallel edges), radial reciprocating (changing radial directions and cuts between two horizontal edges), circular (continuously radial in one direction), and end-cutting, etc. The power source used to drive the blade may be one of: pneumatic, hydraulic, manual mechanical, electrical, solar, etc. The probe also includes several channels that may be used for providing live aspiration and removal of severed tissue and fluids, as well as insufflation of gases and optionally, pharmaceuticals and/or a secondary therapy.

Abstract: An expandable introducer sheath can actively be induced to reduce in diameter or enlarge in diameter due to a braided internal structure that has axial strands connected to its distal end. The introducer sheath is delivered to the blood vessel or other tubular member of the body in a smaller diameter configuration with the axial strands in compression. The catheter is flexible and can be delivered to eccentrically shaped and tortuous vessels. Once the catheter is in position, the axial strands are placed into tension to cause the introducer sheath to assume a larger diameter configuration that will help straighten out tortuous vessels. The access site into the blood vessel is expanded via a radial expansion that is less traumatic. Passage of a larger interventional catheter can proceed through the larger diameter sheath configuration.

Abstract: Apparatus and methods are provided for accessing body lumens and/or for delivering instruments into body lumens, e.g., vessels within a patient's vasculature. A flexible sheath is provided that is expandable from a contracted condition to an enlarged condition wherein the sheath at least partially defines a lumen therein. The sheath is lubricious and has a relatively thin wall, thereby providing a collapsible/expandable guide for delivering fluids and/or instruments through tortuous anatomy and/or into relatively narrow passages. The sheath is advanced from an entry site to a body lumen in the contracted condition. Once the sheath reaches a target body lumen, the sheath is expanded to the enlarged condition, thereby defining a lumen within the sheath, and fluids and/or instruments are introduced into the body lumen via the sheath lumen. Upon completing the procedure, the sheath is removed from the body lumen.

Abstract: A device for providing access to an implantable fluid transfer port, comprises a needle extending to a distal end insertable into body to enter a reservoir of a port implanted therein and an actuation member extending through a lumen of the needle from an actuator which remains external to a living body accessible to a user thereof in combination with an obturator coupled to a distal end of the actuation member, an outer diameter of the obturator substantially matching an inner diameter of the lumen of the needle so that, when retracted into the lumen, the obturator seals a distal opening thereof and an anchoring mechanism coupled to the actuation member proximally of the obturator, the anchoring mechanism being moved to an expanded state in which an outer diameter of the anchoring mechanism exceeds an outer diameter of the needle when moved out of the lumen of the needle.

Abstract: An introducer for providing intravascular access to a patient is disclosed, and includes a dilator and sheath that are configured to prevent peelback, or “fishmouthing,” of the sheath during introducer advancement. In one embodiment, the introducer comprises a dilator including a distal tapered region, and a sheath including an inner bore that receives the dilator such that a portion of the tapered region of the dilator extends from the sheath distal end. A distal outer surface of the sheath includes a first curved portion defined by a first radius and extending proximally from the distal end of the sheath to a first end point, and a second curved portion defined by a second radius and extending proximally from the first end point to a second end point. Additionally, an interference fit is established between the dilator tapered region and the sheath distal end to further prevent sheath end deformation.

Abstract: A steerable guidewire having a deflectable distal tip which comprises a longitudinal hypotube and an interlocking spring coil attached to the distal end of the hypotube and also includes a longitudinally movable deflection member which is attached to the distal end of the spring coil and a tip retaining ribbon which extends from the distal end of the hypotube to the distal end of the spring coil for providing very precise deflection of the distal tip. The distal end of the deflection member has “skived,” or tapered, sides to enhance the flexibility of the guidewire.

Abstract: A method for forestalling or therapy, at least partially, of BPH or prostate cancer comprising identifying a reflux of venous blood to the prostate and impeding the reflux by treating veins effecting or conveying the reflux, and related apparatus and kit.

Abstract: Described herein are devices and systems for accessing a spine and particularly the epidural region of the spine and methods of using these systems and devices to access the spine or regions of the spine. In particular, cannulas that may be anchored to the ligamentum flavum or the periosteum are described. Ligamentum flavum access tools are also described. These tools may be used with (or without) an anchoring cannula to penetrate the ligamentum flavum and provide access to the epidural space without risk of injury to other structures within the epidural space. The devices, methods and systems described herein are particularly useful in minimally invasive surgical (MIS) uses. The devices, methods and systems described herein may be used for performing spinal decompressions and other spinal procedures.

Abstract: The disclosure relates to an a catheter sheath introducer that is capable of being expanded from first diameter to second diameter in order to accommodate differently sized medical devices to be introduced by the sheath introducer. The device is structured such that it does not foreshorten when expanded.

Abstract: Access system for forming and enlarging a percutaneous penetration are disclosed. The apparatus includes a radically expandable dilation assembly having a radically expandable sleeve body and a handle portion operatively coupled to the proximal end of the radically expandable sleeve body. The access system further includes an expansion assembly having an expansion member configured and adapted to radically expand the sleeve body upon insertion therein of the expandable member. The handle portion including a seal disposed across an aperture formed therein for creating a fluid-tight seal around a proximal end of the expansion member. The handle portion including a valve stem operatively and fluidly coupled thereto for delivering a fluid into the aperture of the handle portion. The expansion member including a coating for reducing the force required to slidably insert the expansion member into the sleeve body of the dilation assembly.

Abstract: Disclosed is an expandable transluminal sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion of at least a part of the distal end of the sheath to a second, enlarged cross-sectional configuration. The sheath is configured for use in the vascular system and has utility in the performance of procedures in the left atrium. The access route is through the inferior vena cava to the right atrium, where a trans-septal puncture, followed by advancement of the catheter is completed. The distal end of the sheath is maintained in the first, low cross-sectional configuration during advancement to the right atrium and through the atrial septum into the left atrium. The distal end of the sheath is subsequently expanded using a radial dilatation device.

Abstract: An instrument for facilitating insertion of a catheter through a subcutaneous tunnel includes a tunneling stylet defining a longitudinal axis and having leading and trailing ends, a bifurcated segment adjacent the leading end of the tunneling stylet and a releasable cover releasably mountable to the leading end of the tunneling stylet to substantially enclose the bifurcated segment. The bifurcated segment includes first and second elements adapted for reception within respective lumens of a catheter. The instrument may further include a dilation member which is releasably mountable to the leading end of the tunneling stylet in the absence of the releasable cover. The dilation member is dimensioned to generally increase an internal dimension of the subcutaneous tunnel. The first and second elements of the bifurcated segment each include an outer peripheral rib dimensioned to facilitate gripping engagement with an internal surface of respective lumens of the catheter.

Abstract: Disclosed is an expandable transluminal sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion of at least a part of the distal end of the sheath to a second, enlarged cross-sectional configuration. The sheath is configured for use in the vascular system and has utility in the performance of procedures in the left atrium. The access route is through the inferior vena cava to the right atrium, where a trans-septal puncture, followed by advancement of the catheter is completed. The distal end of the sheath is maintained in the first, low cross-sectional configuration during advancement to the right atrium and through the atrial septum into the left atrium. The distal end of the sheath is subsequently expanded using a radial dilatation device.