摘要:
An implantable medical lead for use with an implantable cardioverter defibrillator, a method of manufacture and a system employing the lead and cardioverter/defibrillator in combination. The lead is provided with an elongated insulative lead body carrying a cardioversion/defibrillation electrode, which includes a first portion displaying essentially equal attenuation of positive and negative voltage pulses and a second portion displaying differential attenuation of positive and negative voltage pulses. The cardioveter/defibrillator provides a biphasic pulse in which a higher amplitude phase of the pulse is differentially attenuated by the electrode. The electrode is fabricated in whole or in part of a valve metal such as tantalum, anodized and annealed to provide a thick, durable oxide coating.
摘要:
A biomedical lead conductor cable formed of a core wire strand and a plurality of perimeter wire strands wrapped in a helical pattern around the core wire strand, wherein the core wire strand is formed of M wires and the perimeter wire strands are formed of N wires. The core wire strand is formed of a first core wire and M-1 first peripheral wires helically wrapped about the first core wire in a non-overlapping manner, the first core wire having a mechanical strength exceeding the mechanical strength of each first peripheral wire and an electrical conductivity lower than the electrical conductivity of each first peripheral wire. Each perimeter wire strand is formed of a second core wire and N-1 second peripheral wires helically wrapped about the second core wire in a non-overlapping manner, the second core wire conductor having a mechanical strength exceeding the mechanical strength of each second peripheral wire and an electrical conductivity lower than the electrical conductivity of each second peripheral wire. In a preferred embodiment M=N, and the first core wire is formed of a solid metal or metal alloy, whereas first peripheral wires are formed of a composite conductor wire having a core of high conductivity material surrounded by a cladding of lower conductivity material. The second core wire is also preferably formed of a composite conductor wire. The diameters of the first and second core wires exceed the diameters of the first and second peripheral wires, respectively to provide a spacing between adjacent peripheral wires wound helically about the core wires. Moreover, preferably, the diameter of the core wire strand exceeds the diameter of the perimeter wire strands to provide a spacing between the adjacent perimeter wire strands wound about the core wire strand.
摘要:
Systems and methods for controllably variable fluid flow are disclosed that provide the ability to modify the effective cross-sectional area of the fluid delivery conduit available for fluid flow. Accordingly, selective control of these configurations allows fluid flow to be regulated as desired while the fluid delivery pressure remains the same. Additional configurations provided herein allow for the selective manipulation of a footprint or therapeutic pattern achievable with the medical device during a single procedure, negating the need for the removal and insertion of multiple devices to achieve the same variations in treatment geometry or characteristics.
摘要:
A stented valve including a generally tubular stent structure that has a longitudinal axis, first and second opposite ends, a plurality of commissure support structures spaced from the first and second ends and extending generally parallel to the longitudinal axis, at least one structural wire positioned between each two adjacent commissure support structures, and at least one wing portion extending from two adjacent commissure support structures and toward one of the first and second ends of the stent structure. The stented valve further includes a valve structure attached within the generally tubular stent structure to the commissure support structures.
摘要:
A device and method for valve replacement or valve repair is disclosed comprising the steps of acquiring an anatomical image of a patient, correlating the image to the patient, guiding a valve replacement delivery member or a valve repair delivery member within the patient while tracking the position of the delivery member in the patient, positioning the valve replacement member or valve repair member in a desired position to place a valve or repair valve and removing the delivery member from the patient. In one aspect of the invention, a delivery system is provided for percutaneous delivery of a heart valve to a predetermined position in the heart of a patient, where the delivery system itself includes features that allow it to be accurately positioned in the heart. In another aspect of the invention, a delivery system is provided for percutaneous repair of a heart valve in the heart of a patient, where the repair system itself includes features that allow it to be accurately positioned in the heart. In another aspect of the invention, a method and device are provided that involve imaging a native root using an interoperative technique, then introducing a device that is easily visualized in a chosen imaging modality.
摘要:
A method for closing an opening at a target site including bodily tissue including embedding a plurality of self-closing clips into the target site in a spaced apart manner about a perimeter of the opening. Each of the clips has opposing clip ends and an intermediate segment. A flexible tether is coupled to the embedded clips to form a loop about the opening perimeter. A pulling force is applied onto at least one of the loop ends, thereby drawing the perimeter of the opening onto itself to completely close the opening. The loop ends are secured to maintain the target site in a closed state. In some embodiments, the target site is apical cardiac tissue, and the method is performed as part of a trans-apical access procedure.
摘要:
A method of deploying an implantable stented device in an anatomical location of a patient, including the steps of providing a delivery system with first and second stent engagement structures at its distal end, attaching a first structural element of the stented device to the first stent engagement structure and attaching a second structural element of the stented device to the second stent engagement structure, advancing the stented device to an implantation site, and sequentially disengaging the first structural element of the stented device from the first stent engagement structure of the delivery system and then disengaging the second structural element of the stented device from the second stent engagement structure.
摘要:
Heart pacing systems include at least one electronic or biological pacemaker as a primary pacemaker, and at least one electronic or biological pacemaker as a backup pacemaker. When implanted, the primary pacemaker(s) produce primary pacing stimuli that modulate cardiac function. The backup pacemaker(s) provide backup pacing stimuli when the electronic pacemaker is unable to modulate cardiac function at the predetermined pacing rate. The heart pacing systems are implemented by implantation in regions where they can provide pacing stimuli to cardiac tissue.
摘要:
A catheter body includes an exit port over which a pressure responsive sleeve is formed that allows material to exit a lumen of the catheter body at a given pressure. In one embodiment, a surface of the sleeve is approximately flush with a surface of the catheter body. In another embodiment the sleeve includes a tapered edge.
摘要:
A surface area of an IMD electrode is increased by forming a conductive layer over an external portion of a sidewall of an IMD connector header and electrically coupling the conductive layer of the connector header to a conductive mounting surface of a hermetically sealed IMD housing; wherein the conductive mounting surface is an extension of an external conductive surface of the IMD, which external conductive surface forms the IMD electrode that is increased in surface area by the conductive layer formed over the connector header.