摘要:
A method for transmyocardial revascularization of the heart of a patient includes positioning an active electrode surface in close proximity to a target site on the wall of a patient's heart, and applying high frequency voltage between the active voltage surface and a return electrode to ablate tissue at the heart wall. The high frequency voltage ablates, i.e. volumetrically removes the heart tissue, and the electrode surface is axially translated into the space vacated by the removed tissue to bore a channel through the heart tissue. The active electrode surface may be introduced into the thoracic cavity and placed adjacent the epicardium to form an inward channel toward the ventricular cavity, or it may be delivered into the ventricular cavity of the heart and positioned adjacent the endocardium to form a channel extending outward towards the epicardium. In either case, the channels formed through the myocardium promote direct communication between blood within the ventricular cavity and that of existing myocardial vasculature to increase blood flow to the heart tissue.
摘要:
An electrosurgical probe (10) comprises a shaft (13) having an electrode array (58) at its distal end and a connector (19) at its proximal end for coupling the electrode array to a high frequency power supply (28). The shaft includes a return electrode (56) recessed from its distal end and enclosed within an insulating jacket (18). The return electrode defines an inner passage (83) electrically connected to both the return electrode and the electrode array for passage of an electrically conducting liquid (50). By applying high frequency voltage to the electrode array and the return electrode, the electrically conducting liquid generates a current flow path between the return electrode and the electrode array so that target tissue may be cut or ablated. The probe is particularly useful in dry environments, such as the mouth or abdominal cavity, because the electrically conducting liquid provides the necessary return current path between the active and return electrodes.
摘要:
An electrosurgical probe (10) comprises a shaft (13) having an electrode array (58) at its distal end and a connector (19) at its proximal end for coupling the electrode array to a high frequency power supply (28). The shaft includes a return electrode (56) recessed from its distal end and enclosed within an insulating jacket (18). The return electrode defines an inner passage (83) electrically connected to both the return electrode and the electrode array for passage of an electrically conducting liquid (50). By applying high frequency voltage to the electrode array and the return electrode, the electrically conducting liquid generates a current flow path between the return electrode and the electrode array so that target tissue may be cut or ablated. The probe is particularly useful in dry environments, such as the mouth or abdominal cavity, because the electrically conducting liquid provides the necessary return current path between the active and return electrodes.
摘要:
An electrosurgical probe comprises a shaft having an electrode array disposed over a recessed surface at its distal end. The electrode array includes a plurality of isolated electrode terminals, and an electrosurgical power supply may be connected to the array via a connector at the distal end of the probe. The electrosurgical power supply will be provided with a plurality of independently limited or controlled current sources. By applying very high frequency electrical energy to the electric array with the power supply, target issue may be ablated while heat dissipation through low impedance past is minimized. The probe is particularly suitable for treatment of surfaces of body lumens, such as the mucosal surface within an enlarged prostate.
摘要:
A catheter system is provided that includes an electrode array near the distal end of the catheter. High frequency current is supplied between the electrodes of the array and a common electrode to cause heating of material lying between the electrodes. The catheter may include means for steering it through the lumen. In a preferred embodiment, the steering means includes a plurality of steering wires in contact with the catheter body. The steering wires may be formed of a shape-memory alloy. Wires of such an alloy may be made to contract when heated above a preselected transition temperature. The wires may be heated by the selective conduction of electrical current through them. Conduction of current through the steering wires is controlled based on the current flowing through the electrodes of the array. An inflatable balloon may be included proximal to the electrode array for dilating the vessel after the occlusion has been penetrated by the electrode array. The balloon may be shielded and protected behind a portion of the catheter having a diameter greater than the diameter of the uninflated balloon disposed about the catheter body. The catheter will include means for protecting the walls of the vessel from exposure to electrical current from the electrodes. This will commonly include switching means or other means for current control. The vessel wall may also be protected by setting the electrodes back some distance from the outer edge of the distal tip.
摘要:
This invention provides a method and an apparatus for selectively heating a resistive mass which partially or fully occludes a particular tubal passage, such as a blood vessel or the urethra. As a result, the tubal passage is effectively softened or weakened, allowing the tubal passage to be more readily recanalized by expansion of a balloon or other dilatation means. This invention also provides a method and an apparatus for effectively boring through a partially or fully occluded tubal passage by simultaneously applying both (1) heat to the occlusive mass surrounding the tip of the catheter and (2) pressure against the mass within the partially or fully occluded passage.
摘要:
This invention provides a method and apparatus for selectively heating an atheromatous mass which partially or fully occludes a particular blood vessel. As a result, the occlusive mass is effectively softened or weakened, allowing the occlusive mass to be more readily recanalized by expansion of a balloon or other dilitation means. This invention also provides a method and apparatus for effectively boring through a partially or fully occluded blood vessel by simultaneously applying both (1) heat to the occlusive mass surrounding the tip of the catheter and (2) pressure against the mass within the partially or fully occluded blood vessel.
摘要:
An electrosurgical probe (10) comprises a shaft (13) having an electrode array (58) at its distal end and a connector (19) at its proximal end for coupling the electrode array to a high frequency power supply (28). The shaft includes a return electrode (56) recessed from its distal end and enclosed within an insulating jacket (18). The return electrode defines an inner passage (83) electrically connected to both the return electrode and the electrode array for passage of an electrically conducting liquid (50). By applying high frequency voltage to the electrode array and the return electrode, the electrically conducting liquid generates a current flow path between the return electrode and the electrode array so that target tissue may be cut or ablated. The probe is particularly useful in dry environments, such as the mouth or abdominal cavity, because the electrically conducting liquid provides the necessary return current path between the active and return electrodes.
摘要:
An electrosurgical probe comprises a shaft having an electrode array (12) at its distal end and a connector at its proximal end. The array (12) includes a plurality of isolated electrode terminals, and an electrosurgical power supply (28) is provided with a multiplicity of independently limited or controlled current sources and a connector. The electrosurgical probe and the power supply may be connected through their respective connectors so that the independent current sources are connected to individual electric terminals. By applying very high frequency electrical energy to the electrode array, target tissue may be cut or ablated while heat dissipation through low impedance paths, such as blood and normal saline, will be minimized.
摘要:
The present invention provides systems, apparatus and methods for selectively applying electrical energy to body tissue in order to incise, dissect, harvest or transect tissues or an organ of a patient. The electrosurgical systems and methods are useful, inter alia, for accessing, dissecting, and transecting a graft blood vessel, such as the internal mammary arteries (IMA) or the saphenous vein, for use in a by-pass procedure. A method of the present invention comprises positioning an electrosurgical probe adjacent the target tissue so that one or more active electrode(s) are brought into at least partial contact or close proximity with a target site in the presence of an electrically conductive fluid. A high frequency voltage is then applied between the active electrode and one or more return electrode(s). During application of the high frequency voltage, the electrosurgical probe may be translated, reciprocated, or otherwise manipulated such that the active electrode is moved with respect to the tissue. The present invention volumetrically removes the tissue at the point of incision, dissection, or transection in a cool ablation process that minimizes thermal damage to surrounding, non-target tissue.