Abstract: The disclosure describes a medical electrical lead including bonding strip to bond an elongate electrode coil to an elongate lead body to reduce damage to the medical electrical lead during manipulation of the medical electrical lead. The elongate lead body extends from a proximal end to a distal end and includes a proximal portion and a distal portion. The elongate electrode coil surrounds at least part of the distal portion of the elongate lead body. The bonding strip extends axially along the elongate electrode coil and extends only partially around the circumference of the elongate electrode coil for at least part of the length of the bonding strip, where at least a portion of the bonding strip is bonded to the elongate lead body to fix a portion of the elongate electrode coil to the elongate lead body.

Abstract: A pericardial implantable cardioverter defibrillator (ICD) may be delivered to the heart through the chest wall using an ultrasound image guided catheter. The ICD may comprise a patch and wire leads which may be secured by a clam shell-like pad at a distal end and comprise a pig-tail shaped securing tail at the other end so that the ICD is firmly attached to the pericardium of a human heart. The ICD may be attached where most needed and serve as either a pacemaker or a defibrillator. In one embodiment, the ICD may emit radio frequency warning signals of heart failure sensed when pacemaker or defibrillator usage is rendered necessary.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example medical device may include an implantable medical device. The implantable medical device may include an implantable pacing member having a housing and a lead input. A lead may be coupled to the lead input. The lead may be designed to extend along a pericardial space, epicardium, or both and engage a heart chamber. A passageway may be defined along a portion of the length of the lead.

Abstract: A tine portion for an implantable medical device includes a hook segment and a distal segment terminated by a tissue-piercing tip, wherein the distal segment extends from the hook segment to the tip. The hook segment, which is elastically deformable from a pre-set curvature, has one of: a round cross-section and an elliptical cross-section, while the distal segment has a flattened, or approximately rectangular cross-section. One or a pair of the tine portions may be integrally formed, with a base portion, from a superelastic wire, wherein the base portion is configured to fixedly attach to the device, for example, being captured between insulative members of a fixation subassembly.

Abstract: Methods and apparatuses are provided for treating cardiac conductive disorders that include implantation of a network of material that adaptively corrects the electrical conductivity of heart tissues and restores “normal” conductance. The methods and apparatuses disclosed herein involve the delivery of a material to a subject's heart in order to restore normal conductance in a minimally invasive, tunable, localized, and reversible manner, without artificial electrical stimulation.

Abstract: Disclosed herein is an implantable lead configured to administer electrotherapy to a patient heart from an implantable pulse generator. The lead may include a lead body and an attachment structure. The lead body includes a bifurcated distal region including first and second lead body branches each terminating in a distal end. At least one of the first lead body branch or second lead body branch includes an electrode. The attachment structure couples together the distal ends of the first and second lead body branches. The attachment structure is configured to release such that the distal ends of the first and second lead body branches can decouple from each other.

Abstract: A catheter includes an elongated body, a distal assembly with a shape-memory member defining a generally helical form, and a control handle. The control handle may be adapted to actuate a deflection puller wire for deflecting a portion of the elongated body and a contraction wire for contracting the generally helical form. The generally helical form carries irrigated ablation ring electrodes. A nitinol support member with shape memory extends through the distal assembly and into the elongated body to provide the helical form. The support member may have a varying stiffness along its length, for example, a decreasing stiffness toward a distal end of the support member. The support member can also be hollow so that it can receive a mandrel whose stiffness is greater than that of the support member.

Abstract: A catheter includes an elongated body, a distal assembly with a shape-memory member defining a generally circular form, and a control handle adapted to actuate a deflection puller wire for deflecting a portion of the elongated body, and a contraction wire for contracting the generally circular form. The generally circular form which carries at least one ring electrode has an off-edge configuration relative to the elongated body such that a longitudinal axis of the elongated body does not intersect the circumference of the circular form and the generally circular form spirals about the longitudinal axis of the elongated body. Moreover, the circular form can have an on-axis configuration such that the longitudinal axis of the elongated body is axially aligned with a central longitudinal axis of the circular form, or an off-axis configuration such that these axes are axially offset from each other.

Abstract: A catheter apparatus for treatment of a human patient is described, the catheter apparatus having a central axis and comprising a shaping structure moveable between a delivery state having a first helical shape, and a deployed state having a second helical shape. The shaping structure is configured to have a reverse taper with a structural diameter that varies over the length of the shaping structure such that the structural diameter of the shaping structure at the proximal end is smaller than the structural diameter of the shaping structure at the distal end.

Abstract: A catheter includes an elongated body, a distal assembly with a shape-memory member defining a generally circular form, and a control handle adapted to actuate a deflection puller wire for deflecting a portion of the elongated body, and a contraction wire for contracting the generally circular form. The generally circular form which carries at least one ring electrode has an off-edge configuration relative to the elongated body such that a longitudinal axis of the elongated body does not intersect the circumference of the circular form and the generally circular form spirals about the longitudinal axis of the elongated body. Moreover, the circular form can have an on-axis configuration such that the longitudinal axis of the elongated body is axially aligned with a central longitudinal axis of the circular form, or an off-axis configuration such that these axes are axially offset from each other.

Abstract: Catheter apparatuses, systems, and methods for achieving renal neuromodulation by intravascular access are disclosed herein. One aspect of the present technology, for example, is directed to a treatment device having a multi-electrode array configured to be delivered to a renal blood vessel. The array is selectively transformable between a delivery or low-profile state (e.g., a generally straight shape) and a deployed state (e.g., a radially expanded, generally spiral/helical shape). The multi-electrode array is sized and shaped so that the electrodes or energy delivery elements contact an interior wall of the renal blood vessel when the array is in the deployed (e.g., spiral/helical) state. The electrodes or energy delivery elements are configured for direct and/or indirect application of thermal and/or electrical energy to heat or otherwise electrically modulate neural fibers that contribute to renal function.

Abstract: Devices, systems, and methods for myocardial infarct border zone reinforcement. In at least one embodiment of a suction/infusion catheter for facilitating myocardial infarct border zone reinforcement, the catheter includes one or more apertures defined along a portion of the catheter at or near a distal end of the catheter, a first configuration when the suction/infusion catheter is at least partially extended from a delivery catheter, and a second configuration when the at least one suction/infusion catheter is positioned within the delivery catheter, the second configuration different from the first configuration, wherein the suction/infusion catheter, when introduced into a pericardial space surrounding a heart at or near a myocardial infarct border zone, is operable to inject a glue-like substance through a lumen of the suction/infusion catheter and out from the one or more apertures to deliver the glue-like substance into the pericardial space at or near the myocardial infarct border zone.

Abstract: A pacing lead (20) having a lead body (22) with a central lumen and provided with structure for retaining the lead body to a wall of the coronary network, and a hollow tubular extension (26), bearing an active region of the lead and also traversed by a central lumen (28) communicating with the inner lumen of the lead body, so as to allow implantation by an over the wire technique. The hollow tubular extension has an outside diameter of between 2 and 3 French (0.66 and 1 mm) to allow implantation deep in the coronary sinus network, and it comprises on its outer surface an electrically insulated peripheral conductor, except for denuded areas intended to come into contact with the wall of a target vein and form a network of stimulation electrodes (32, 34) electrically connected together.

Abstract: Techniques for biventricular pacing include a rigid shaped stylet approximating curves of a coronary sinus and branch vein. Some techniques include a parasternal coronary sinus cannula comprising an outer sheath and an obturator. The obturator is removeably disposed inside the outer sheath from a device end of the hollow shaft. The obturator includes a flexible stem that fits snugly inside the hollow shaft, a malleable core disposed inside the flexible stem, a tapered tip that extends beyond a cardiac end of the shaft when the obturator is disposed inside the outer sheath, and a sensor for determining properties of the subject in a vicinity of the tapered tip. An optional pressure-seal, such as a tent, connected to suction maintains negative intrepleural pressure for insertion under local anesthesia.

Abstract: A lead includes a lead body and an electrode disposed proximate a distal end of the lead body. A retaining member is disposed proximate the distal end of the lead and adapted to retain the electrode proximate an interatrial septum when the retaining member is located on a left atrial side of the interatrial septum.

Abstract: An electrode coupling output system associated with an electrode catheter that provides indication to the physician via the navigation system, concerning the electrical coupling of an electrode, such as an ablative or mapping electrode, with a patient. The indication may be provided by changing the color or other display characteristics of the electrode on the navigation system display or by way of providing a waveform indicating the electrode coupling. In this manner, electrode coupling information is provided to a physician in a manner that minimizes physician distraction.

Abstract: An intra-cardiac implantable medical device (IIMD) system may include a housing and an intra-cardiac (IC) device extension. The housing may be configured to be implanted entirely within a local chamber of the heart. The housing includes a base configured to be secured to the local chamber. The IC device extension may include a proximal end, a distal end, and an extension body extending there between. The proximal end may be coupled to the housing and configured to be located in the local chamber. The extension body may include an IE orientation segment connected to a chamber transition segment that is sufficient in length to extend from the local chamber into an adjacent chamber. The IE orientation segment is configured to be lodged within the adjacent chamber in order to stabilize the system within heart.

Abstract: A steerable multi-linked device. The device includes a first multi-linked mechanism and a second multi-linked mechanism. At least one of the first and second multi-linked mechanisms is steerable and includes a modular link assembly at an end thereof. The modular link assembly includes a base, and a tip removably connected to the base.

Abstract: An implantable lead includes a lead body. A plurality of conductors are disposed within the lead body and electrically couple at least one electrode to at least one terminal. At least one of the conductors includes a plurality of units. Each of the units includes a first conductor segment extending along the lead body from a beginning point to a first position, a second conductor segment extending from the first position to a second position, and a third conductor segment extending along the elongated member from the second position to an endpoint. The conductor segments are arranged so as to form alternating single-coil regions and multi-coil regions. At least one support element is disposed along at least a portion of at least one of the single-coil regions and is configured and arranged to increase the stiffness of the at least one of the single-coil regions.

Abstract: Techniques include determining a first vector of temporal changes in electrical data measured at multiple electrical sensors positioned at corresponding locations on a surface of a living body due to a natural electrical pulse. A different vector of temporal changes in electrical data measured at the same electrical sensors is determined due to each stimulated signal of multiple stimulated signals within the living body. Stimulated position data is received, which indicates a different corresponding position within the living body where each of the stimulated signals originates. The site of origin of the natural electrical pulse is determined based on the first vector and the multiple different vectors and the stimulated position data. Among other applications, these techniques allow the rapid, automatic determination of the site of origin of ventricular tachycardia arrhythmia (VT).

Abstract: A lead having a pre-formed biased portion is adapted for implantation with a body vessel and for connection to a signal generator. The lead is constructed and arranged so that when it is implanted, the electrodes are biased toward a vessel wall by the preformed biased portion, which operates to fixate the lead against the vessel wall.

Abstract: Medical devices and therapeutic methods for use in the field of cardiology, cardiac rhythm management and interventional cardiology, and more specifically to catheter-based systems for implantation of pacing leads and electrodes, or intramural myocardial reinforcement devices, within the myocardial wall of the heart, such as the ventricles, to provide improved cardiac function.

Abstract: A cardiac lead adapted for fixation at least partially within a cardiac vessel. The lead includes, in one embodiment, an elongate lead body defining a proximal region and a distal region including a distal end region having at least one electrode and a distal tip. The distal end region is configured such that the electrode and the distal tip can be implanted in the cardiac vessel. Stiffening structures in the distal region of the lead are adapted to stiffen selected portions of the lead for fixation of the electrode within the cardiac vessel. In some embodiments, the stiffening structures include an implantable member adapted to be implanted in a lumen of the lead. In other embodiments, the stiffening structures include a sheath adapted to be deployed over the lead body. In still other embodiments, the stiffening structures are integral to the lead and/or the lead body.

Abstract: A neurostimulating lead having a stent-like anchor is described. A distal portion of the lead is mounted to an exterior of an expandable, stent-like lead anchor. The stent-like lead anchor is formed from a superelastic material and is adapted to transition from a collapsed configuration to an expanded configuration upon deployment in a vessel. In the expanded configuration, the lead anchor presses the distal portion of the lead against at least one vessel wall of a vessel in which the lead is deployed securing and stabilizing the distal portion of the lead within the vessel.

Abstract: The intrapericardial lead includes a lead body having a proximal portion and a flexible, pre-curved distal end portion. The distal end portion carries at least one electrode assembly containing an electrode adapted to engage pericardial tissue. The distal end portion further carries a pre-curved flexible wire member having ends attached to spaced apart points along the distal end portion of the lead body, the flexible wire member having a normally expanded state wherein an intermediate portion of the wire member is spaced apart from the distal end portion, and a generally straightened state wherein the wire member and the distal end portion are disposed in a more parallel, adjacent relationship so as to present a small frontal area to facilitate delivery into the pericardial space. The wire member re-expands to its normal state after delivery into the pericardial space to anchor the distal end portion of the lead body relative to the pericardial tissue.

Abstract: A steerable multi-linked device. The device includes a first multi-linked mechanism and a second multi-linked mechanism. At least one of the first and second multi-linked mechanisms is steerable and includes a modular link assembly at an end thereof. The modular link assembly includes a base, and a tip removably connected to the base.

Abstract: An electrode coupling output system associated with an electrode catheter that provides indication to the physician via the navigation system, concerning the electrical coupling of an electrode, such as an ablative or mapping electrode, with a patient. The indication may be provided by changing the color or other display characteristics of the electrode on the navigation system display or by way of providing a waveform indicating the electrode coupling. In this manner, electrode coupling information is provided to a physician in a manner that minimizes physician distraction.

Abstract: An implantable lead includes a lead body. A plurality of conductors are disposed within the lead body and electrically couple at least one electrode to at least one terminal. At least one of the conductors includes a plurality of units. Each of the units includes a first conductor segment extending along the lead body from a beginning point to a first position, a second conductor segment extending from the first position to a second position, and a third conductor segment extending along the elongated member from the second position to an endpoint. The conductor segments are arranged so as to form alternating single-coil regions and multi-coil regions. At least one support element is disposed along at least a portion of at least one of the single-coil regions and is configured and arranged to increase the stiffness of the at least one of the single-coil regions.

Abstract: Various configurations of systems that employ leadless electrodes to provide pacing therapy are provided. In one example, a system that provides multiple sites for pacing of myocardium of a heart includes wireless pacing electrode assemblies that are implantable at sites proximate the myocardium using a percutaneous, transluminal, catheter delivery system. Also disclosed are various configurations of such systems, wireless electrode assemblies, and delivery catheters for delivering and implanting the electrode assemblies.

Abstract: A method of inserting a pacing lead having a preformed shape into a coronary sinus to pace the left atrium includes providing a lead having an elongated body and proximal and tip sections. The sections are configured such that a first angle less than 90 degrees is defined between the lead body and proximal section and a second angle is defined between the tip and proximal sections. The method further comprises advancing the pacing wire towards the opening of the coronary sinus and advancing the wire into the coronary sinus, such that the first angle is compressed by the coronary sinus opening and a tip electrode included on the tip section contacts the wall of the coronary sinus near the left atrium operably extending the second angle to assure constant contact between the wall of the coronary sinus and the tip electrode.

Abstract: A pacing lead for implantation in a coronary sinus having an opening and a wall defining an interior and presenting a diameter dimension. The pacing lead includes an elongated lead body, a resilient fixation element, and at least one electrode on either the lead body or the fixation element. The fixation element extends from the pacing portion and defines a loop structure laterally adjacent the pacing portion. The loop structure presents a predetermined width dimension greater than the diameter dimension of the coronary sinus, wherein when the loop structure is inserted into the opening of the coronary sinus, the loop structure is laterally compressed by the wall of the coronary sinus and the electrode is biased against the wall of the coronary sinus.

Abstract: Some embodiments of an electrical stimulation system employ wireless electrode assemblies to provide pacing therapy, defibrillation therapy, or other stimulation therapy. In certain embodiments, the wireless electrode assemblies may include a guide wire channel so that each electrode assembly can be advanced over a guide wire instrument through the endocardium. For example, a distal tip portion of a guide wire instrument can penetrate through the endocardium and into the myocardial wall of a heart chamber, and the electrode assembly may then be advanced over the guide wire and into the heart chamber wall. In such circumstances, the guide wire instrument (and other portions of the delivery system) can be retracted from the heart chamber wall, thereby leaving the electrode assembly embedded in the heart tissue.

Abstract: A steerable multi-linked device. The device includes a first multi-linked mechanism and a second multi-linked mechanism. At least one of the first and second multi-linked mechanisms is steerable and includes a modular link assembly at an end thereof. The modular link assembly includes a base, and a tip removably connected to the base.

Abstract: A lead includes a lead body with a stylet receiving lumen, a distal tip, and a distal portion proximal of the distal tip that is biased to assume a non-linear configuration. Insertion of a stylet into the lumen causes the distal portion to transition from the non-linear configuration to a generally linear configuration. The lead also includes a first arm member having a distal end and a proximal end coupled to the lead body proximal of the distal tip; and a nosepiece, at least a portion of which is biodegradable. The nosepiece is configured to receive the distal tip of the lead body and the distal end of the first arm member such that the lead body, first arm member and nosepiece form a closed arrangement prior to biodegradation of the nosepiece and an open arrangement after biodegradation of the nosepiece.

Abstract: A lead having pre-formed biased portion is adapted for implantation on or about the heart within the coronary vasculature and for connection to a signal generator. The lead is constructed and arranged so that when it is implanted, the electrodes are housed in the coronary vasculature and are biased toward a vessel wall by the preformed biased portion, which operates to fixate the lead against the vessel wall.

Abstract: A steerable multi-linked device. The device includes a first multi-linked mechanism and a second multi-linked mechanism. At least one of the first and second multi-linked mechanisms is steerable and includes a modular link assembly at an end thereof. The modular link assembly includes a base, and a tip removably connected to the base.

Abstract: A neuron stimulating lead having a stent-like anchor is described. A distal portion of the lead is mounted to an exterior of the lead anchor. The stent-like lead anchor is formed from a superelastic material and is adapted to transition from a collapsed configuration to an expanded configuration upon deployment in a vessel. In the expanded configuration, the lead anchor presses the distal portion of the lead against at least one vessel wall of a vessel in which the lead is deployed securing and stabilizing the distal portion of the lead within the vessel.

Abstract: The intrapericardial lead includes a lead body having a proximal portion and a flexible, pre-curved distal end portion. The distal end portion carries at least one electrode assembly containing an electrode adapted to engage pericardial tissue. The distal end portion further carries a pre-curved flexible wire member having ends attached to spaced apart points along the distal end portion of the lead body, the flexible wire member having a normally expanded state wherein an intermediate portion of the wire member is spaced apart from the distal end portion, and a generally straightened state wherein the wire member and the distal end portion are disposed in a more parallel, adjacent relationship so as to present a small frontal area to facilitate delivery into the pericardial space. The wire member re-expands to its normal state after delivery into the percaridal space to anchor the distal end portion of the lead body relative to the pericardial tissue.

Abstract: A steerable multi-linked device. The device includes a first multi-linked mechanism and a second multi-linked mechanism. At least one of the first and second multi-linked mechanisms is steerable and includes a modular link assembly at an end thereof. The modular link assembly includes a base, and a tip removably connected to the base.

Abstract: A medical lead includes a lead body having at least one conductor extending from a proximal end of the lead body to a distal end of the lead body. The proximal end is adapted to be connected to a pulse generator, and the distal end includes a curved portion. One or more electrodes are operatively connected to the at least one conductor and coupled to the curved portion of the lead body. At least a portion of each of the one or more electrodes includes an arrangement of interconnected, spaced-apart elements that are selectively configured to allow the one or more electrodes to conform to contours of the curved portion during and after implantation of the medical lead.

Abstract: An implantable multi-conductor endocardial lead for a cardiac stimulator includes a tubular lead body of flexible resilient insulative material having a first lumen and a smaller diameter tubular member of similar material having a second lumen is coaxially received in the first lumen. An outer coil conductor is received within an annular cavity between the tubular lead body and the tubular member. An elongated inner coil conductor is received within the second lumen. A tip electrode at the distal end of the lead is coupled to the inner coil conductor and a ring electrode proximally spaced from the tip electrode is coupled to the outer coil conductor. All components except for the outer coil conductor have a normally straight configuration and the outer coil conductor is pre-shaped into a generally circular looped configuration such that, upon assembly, the resulting endocardial lead results in a J-configuration at its distal end.

Abstract: The invention is directed to medical lead designs that facilitate implantation of the leads through tissue. For example, the leads can implanted though tissue for placement of distal tips of the leads in locations on the opposing side of the tissue. The leads include fixation elements, such as flexible tines, that facilitate fixation to the tissue. The fixation elements can protrude from lead at a location more than 5 millimeters from the distal-tip of the lead such that when the distal tip has passed through the tissue, the fixation elements anchor in the tissue.

Abstract: A guide catheter assembly for accessing lateral branch veins of the coronary sinus includes a guide catheter and a pacing lead. The guide catheter has a central lumen therethrough, a proximal end and a distal end pre-formed with a guide curve. The pacing lead is slidably receivable within the guide catheter lumen. The pacing lead has a proximal end and a distal end formed with a first curve and a second curve extending proximally from the first curve. The second curve is adapted to mate with the guide curve to direct the first curve into a selected branch vein of the coronary sinus. The second curve may be pre-formed in the pacing lead, or may be imparted to the pacing lead via a stylet or inner catheter.

Abstract: A method of accessing lateral branch veins of the coronary sinus with a pacing lead and guide catheter assembly. The guide catheter has an open lumen extending therethrough and a distal end provided with a pre-formed guide curve, while the pacing lead has a distal end provided with a first curve and a second curve extending proximally from the first curve. The guide catheter is inserted into an access vessel of the heart and advanced along the access vessel to the coronary sinus. The pacing lead is inserted into the guide catheter lumen and advanced distally through the guide catheter lumen. The pacing lead is rotated by advancing the second curve of the pacing lead through the guide curve to align the first curve with a pre-determined plane. The first curve of the pacing lead into one of the lateral branch veins of the coronary sinus.

Abstract: In one embodiment, the present invention provides a cardiac lead device including a fixation mechanism slidably attached to the lead such that when the fixation mechanism is expanded into contact with a body lumen, the lead may be moved relative to the fixation mechanism if desired. Such lead movement may be limited by complimentary structure on the lead body and the fixation mechanism that prevents the lead from moving unless sufficient force is applied to the lead.

Abstract: An implantable lead is disclosed which includes an elongated lead body having opposed proximal and distal end portions. At least one defibrillation assembly is operatively associated with the distal end portion of the lead body for delivering electrical energy to cardiac tissue. The defibrillation assembly includes a plurality of axially spaced apart conductive hull assemblies that at least partially surround the elongated lead body, and a helically wound shocking coil that extends over the axially spaced apart hull assemblies so that a series of annular void regions are defined by the shocking coil, the lead body, and adjacent hull assemblies, whereby the annular void regions allow the shocking coil to articulate, thereby inhibiting buckling of the shocking coil.

Abstract: A pacing lead having a lead body configured into a pre-formed J-shape. The lead includes a pacing electrode coupled to an intermediate portion of the lead body and located distally from a bottom of the pre-formed J-shape. The lead is adapted to be placed within a heart in a J-shaped configuration with the electrode positioned proximate a ventricular septum or a right ventricular outflow tract such that at least a portion of the distal end of the lead body is located within a pulmonary artery. In one embodiment, the distal end of the lead is configured to be passively fixated within the pulmonary artery. Another aspect includes a lead body wherein a section of the intermediate portion of the lead body is less stiff than adjacent sections of the lead body. The lead includes a pacing electrode coupled to the intermediate portion of the lead body and located distally from the less stiff section.

Abstract: A combined electrical and chemical stimulation lead is especially adapted for providing treatment to intervertebral discs. The combination lead may be placed proximate to intervertebral disc cellular matrix and nucleus pulposus tissue to promote tissue regeneration and repair, as well as nociceptor and neural tissue modulation. The stimulation lead includes electrodes that may be selectively positioned along various portions of the stimulation lead in order to precisely direct electrical energy to stimulate the target tissue. The lead also includes a central infusion passageway or lumen that communicates with various infusion ports spaced at selected locations along the lead to thereby direct the infusion of nutrients/chemicals to the target tissue.

Abstract: A left ventricular lead is provided for placement in a branch vessel of the coronary sinus, the vessel having a vessel wall and an adjacent myocardium. The lead includes a lead body having a central lumen extending therethrough, at least a first electrode on the lead body and at least a first orientation feature protruding from the lead body for orienting one or more of the electrodes into contact with the myocardium. The lead may also include a pre-shaped curvature. The orientation feature may also aid in steering the lead into a selected branch vessel of the coronary sinus and in fixing the lead within the branch vessel.

Abstract: The present invention is a medical assembly comprising an elongated flexible medical device, such as a cardiac lead, and a torquing member, such as a stylet, slidably receivable inside the medical device. The device and member are coupled at their distal ends by a corresponding set of opposing curves. This coupling allows more precise rotational control of the assembly when it is manipulated at its proximal end. In one embodiment, the assembly has a open curvature at its distal end. In another embodiment, the distal end has a closed curvature.