Abstract:
A catheter includes multiple primary leads to deliver energy for ligating a hollow anatomical structure. Each of the primary leads includes a resistive element located at the working end of the catheter. Separation is maintained between the leads such that each lead can individually receive power. The catheter can include a lumen to accommodate a guide wire or to allow fluid delivery. Energy is applied until the diameter of the hollow anatomical structure is reduced to the point where occlusion is achieved. In one embodiment, a balloon is inflated to place the resistive elements into apposition with a hollow anatomical structure and to occlude the structure before the application of energy. The inflated balloon impairs blood flow and facilitates the infusion of saline, or medication, to the hollow anatomical structure in order to reduce the occurrence of coagulation and to improve the heating of the structure by the catheter.
Abstract:
An apparatus for treating a hollow anatomical structure comprises an implant sized for insertion into a hollow anatomical structure. The implant comprises a plurality of loose, bulked fibers. The fibers are formed from one or more bioabsorbable materials.
Abstract:
One embodiment comprises an apparatus for applying energy to a hollow anatomical structure having an inner wall. The apparatus comprises an elongate shaft having a distal end and a proximal end opposite the distal end; and a capacitive treatment element located near the distal end. The capacitive treatment element is sized for insertion into the hollow anatomical structure and placement near the inner wall. The capacitive treatment element is configured to create an electric field that extends at least partially into the inner wall. Other devices and methods for treatment of hollow anatomical structures are disclosed as well.
Abstract:
A control system and method for interactive startup and shutdown of a steam turbine driven chiller unit is provided. The chiller unit includes an integrated central control panel to control operation of both the steam turbine system and the refrigerant system. The central control panel has startup control system to assist an operator manually start the steam turbine system and the refrigerant system and a shutdown control system to assist an operator manually shutdown the steam system and the refrigerant system. Both the startup control system and the shutdown control system include logic for performing necessary protective actions and for notifying an operator when to perform required actions.
Abstract:
A surgical method and apparatus for positioning a diagnostic or therapeutic element within the body. The apparatus may be catheter-based or a probe including a relatively short shaft.
Abstract:
A working end of a catheter includes at least one therapeutic element, such as a resistive heating element, usable to deliver energy for ligating, or reducing the diameter of, a hollow anatomical structure. In certain examples, the catheter includes a lumen to accommodate a guide wire or to allow fluid delivery. In certain embodiments, a balloon is inflated to place resistive element(s) into apposition with a hollow anatomical structure and to occlude the structure. Indexing devices and methods are also disclosed for successively treating portions of the hollow anatomical structure. In certain examples, marks along the catheter shaft provide visual verification to the physician of the relative position of the therapeutic element of the catheter. Embodiments of indexing devices may include pairs of rings and/or hinged arms that move a catheter a desired indexed position between successive treatments.
Abstract:
A catheter assembly comprises a first branch body having a first axis, a second branch body extending in a non-parallel relationship with respect to the first axis, and at least one electrode carried by the second branch body. In use, the first branch body can be located within a pulmonary vein within the left atrium, while the electrode carried by the second branch body is located in contact with endocardial tissue outside the pulmonary vein. Ablation energy can be transmitted from the electrode to contacted endocardial tissue while the first branch body is located within the pulmonary vein.
Abstract:
A control system for a steam turbine driven chiller unit is provided. The control system automatically utilizes the full range of the governor, compressor pre-rotation vanes, and hot gas bypass valve capabilities to control the capacity of the chiller and provide anti-surge and override control functions to prevent undesirable operational ranges while maintaining maximum efficiency of operation.
Abstract:
An intercooled gas turbine is provided having an air cooled heat exchanger and a chiller disposed to remove heat from the cooling medium of the intercooler heat exchanger. During peak hours when the turbine is in operation, the air cooled heat exchanger is used primarily to cool the cooling medium of the intercooler heat exchanger. During off peak hours when the turbine is idle, the air cooled heat exchanger is used to remove heat from the condenser of a chiller system associated with a gas turbine inlet air cooling system. An additional liquid to liquid heat exchanger may be provided in-line between the intercooler heat exchanger and the air cooled heat exchanger to further cool the intercooler heat exchanger cooling medium using chilled water before the cooling medium passes back into the intercooler heat exchanger. The chilled water may be provided directly from the chillers, or from a thermal energy storage tank, or from the cooling coils of a turbine inlet air cooling system.