Medtronic, Inc.

Peter M Mulier

Michael F Hoey

David L Thompson

Mary M Morris

John D Wahlstrand

Xiaoyi Min

Timothy G Laske

Terrell M Williams

John G Keimel

Gregory A Boser

Peter J Pohndorf

An electrosurgery medical device is enhanced with unique solution-assistance, and includes, in combination, co-operating device jaws including jaw portions for manipulating tissue, and a plurality of solution infusion openings defined and spaced along each of the jaw portions, for receiving electrolytic solution and infising the solution onto and into tissue to be manipulated, along said jaw portions. As preferred, the device further comprises at least one, and most preferably, many, longitudinal groove(s) along at least one and most preferably, both, of the jaw portions, with the solution infusion openings located in the groove or grooves. The solution is energized with RF energy and contributes to the functions and beneficial effects of the instrument. The solution exits the openings in the grooves at sufficient flow rates to separate substantially all the operative surfaces of the device from tissue, thereby substantially completely preventing adherence between the operative surfaces and tissue. The solution is further energized to a range of energy densities such that tissues to be affected are sealed against flow of blood, lymphatic fluids, air, and other bodily fluids and gases.

Tissue sealing electrosurgery device and methods of sealing tissue

An electrocautery instrument is provided with a hollow electrode having a source of conductive fluid coupled to a proximal end thereof. Conductive fluid is communicated through said electrode and expelled out of the distal end thereof during electrocautery, forming a 'virtual electrode.' The infused conductive liquid conducts the RF electrocautery energy away from the conductive electrode, thereby displacing the region of thermal generation and reducing the extent of burns and perforations caused by conventional electrocautery electrodes. In one embodiment, the electrode is partially disposed within and extends distally out of a retractable suction tube, such that smoke and fluid are aspirated from the electrocautery site. When the suction tube is fully advanced, the electrode is concealed therein, enabling suction without electrocautery to be performed.

Fluid-assisted electrocautery device

A lead and a lead system for dispersion of a cardioversion/defibrillation electrode formed of one or more small diameter defibrillation electrodes in a heart chamber and for attaching a pace/sense electrode in contact with the heart. The small diameter defibrillation electrode or electrodes extend distally from the distal end of the lead body. If multiple electrodes are employed, they are preferably biased to spread apart when unrestrained and have a cross-section size small enough to be inserted into interstices of trabeculae in the ventricular chamber. The distal ends of the defibrillation electrodes may be free of attachment to the lead body or may be attached by a weak bond to the distal portion of the lead.

Implantable defibrillator and lead system

An ablation catheter and a method of performing cardiac ablation. The catheter is provided with a hollow, helical electrode, which is screwed into cardiac tissue at a desired ablation site and connected to a source of R-F electrical energy to ablate the tissue adjacent the electrode. Prior to ablation, a conductive fluid may be injected through the hollow needle, both to provide for cooling of the tissue adjacent the needle and to increase the conductivity of the tissue in the area of the electrode.

Method and apparatus for R-F ablation

A method and apparatus for ablation of body tissue. A catheter provided with a hollow needle is employed both for mapping the location to be ablated by injection of an excitability reducing agent and for ablating tissue, employing RF energy in conjunction with an injected, conductive fluid.

Method for R-F ablation

An electrocautery device is disclosed. In accordance with one aspect of the invention, the electrocautery electrode/tip is provided with a hollow, conductive tube terminating at its distal end in a ball point type tip. Fluid, preferably conductive fluid, is applied to the proximal end of the hollow electrode/tip, and expelled from the distal end thereof during electrocautery. The ball point distal tip allows the distal tip to be directly applied to the tissue and 'rolled' or slid along the tissue. This allows the distal tip to be moved across the tissue without dragging or snagging on the tissue. In addition, the conductive fluid expelled from the distal tip further lubricates the distal tip as it moves across the tissue. If conductive fluid is used, the conductive fluid emanating from the electrode/tip conducts the RF electrocautery energy away from the distal tip so that it is primarily the fluid, rather than the distal tip that actually accomplishes the cauterizing of tissue. That is, the fluid serves as a 'virtual' electrocautery electrode. Since it is the fluid, rather than the distal tip that cauterizes, coagulates and ablates, no burns or perforations are made to the tissue, reducing the amount of debris at the site. Also, the flow of fluid through the electrode/tip tends to keep the distal tip clean and cool.

Ball point fluid-assisted electrocautery device

An ablation catheter particularly adapted for use in ablation of cardiac tissue. The catheter is provided with an elongated electrode, intended to make contact with tissue to be ablated, in the heart, along its length. The electrode is mounted to a segment of the catheter which is porous, and the catheter is provided with an internal lumen for delivery of a conductive fluid such as Ringer's solution, to the porous portion of the catheter body, so that the conductive solution may be delivered along the entire length of the electrode.

Intracardiac defibrillation leads

A medical electrical lead system featuring a medical electrical lead which features an improved anchoring sleeve. The medical electrical lead and anchoring sleeve cooperate with an introducer sheath to minimize the flow of blood through the introducer sheath during the introduction of the lead into the blood vessel. Specifically, the lead has a connector assembly, a conductor attached thereto and an electrode electrically coupled to the conductor. An insulative sleeve covers the conductor and an annular anchoring sleeve is movably positioned over the insulative sleeve. The anchoring sleeve has a distal end and a proximal end and further has an annular or circumferential seal within the inner lumen at the distal end. The distal end is further tapered along its exterior portion. The taper of the distal end cooperates with an introducer sheath to provide a seal between the outer portion of the anchoring sleeve and the introducer sheath. The circumferential seal on the same distal end cooperates with the medical electrical lead to create a seal between the anchoring sleeve and the medical electrical lead. In such a manner, a hemostatic seal is accomplished such that blood will not flow through the introducer sheath while the lead is within the introducer sheath and being positioned into the body.

Medical electrical lead

A methods and apparatuses for ablation or hyperthermic treatment of body tissue are disclosed, wherein the application of radio-frequency ablative or hyperthermic energy is accompanied by the infusion of a conductive solution into the tissue, such that a virtual electrode is created. The virtual electrode results from the increased conductivity of the tissue in the area being treated due to the presence of conductive solution, such that the area of tissue being treated is enlarged as compared with non-fluid-assisted application of energy. In one embodiment, a catheter having a hollow helical electrode/needle on the distal end thereof is provided, such that the electrode/needle can be screwed into the tissue to be treated. A conductive fluid, such as saline, saturated saline, or Ringer's solution, is infused into the tissue to be treated via the hollow electrode and a lumen extending along the length of the catheter. In another embodiment of the invention, an implantable infusion port for fluid-assisted ablation and/or hyperthermia is provided with an elongate catheter having a hollow electrode/needle on the distal end thereof. The port is subcutaneously implanted with the electrode/needle situated within the tissue to be treated. A percutaneous needle facilitates the introduction of conductive fluid and/or chemotherapeutic agents into the tissue via a lumen in the catheter and the hollow electrode/needle. The percutaneous needle also makes electrical contact with a conductor in the catheter, such that as fluid is being introduced into the tissue, radio-frequency energy may be applied to the tissue being treated.

Method and apparatus for RF ablation and hyperthermia

A cardiac pacemaker with an analog telemetry system. A calibration circuit within the pacemaker is adapted to provide a reference signal of known character to the pacemaker's telemetry system. The reference signal is transmitted across the telemetry link as if it were an actual cardiac signal, and received by an external programmer. Since the reference signal has known, predetermined qualities, the programmer can automatically calibrate and scale the telemetry signal from the pacemaker, thereby increasing the accuracy of the telemetry channel. The increased accuracy is particular useful in assessing rejection of a transplanted heart, which is known to be associated with a 15% decline in the peak R-wave amplitude of the cardiac signal.

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Saint Paul, MN, United States of America

Peter M Mulier