Abstract: Apparatus and methods for performing cryogenic ablation of tissue and adjusting the size and/or location of a cryogenic cooling region. A cooling assembly may include tubes for dispensing and exhausting a coolant or refrigerant. One or both of the tubes may be moved, e.g., slidably adjusted, in order to adjust the location or size of a cryogenic ablation region. The cooling assembly may be integrated into cryogenic ablation devices including a cryogenic balloon device that includes an inner inflatable balloon and another balloon that is at least partially wrapped around the inner balloon and carries refrigerant for performing cryo-ablation. Electrodes permit electrical mapping of tissue before or after cryo-ablation to verify success of the procedure.

Abstract: An embodiment of a system for ablating tissue comprises an electrode configured for use to deliver RF power to ablate the tissue, and a heat flow sensor configured to provide a measurement of heat flow from the electrode to blood or irrigation fluid. According to some embodiments, the system further comprises an RF source configured to generate RF power connected to the electrode (PE) to ablate tissue, and a controller configured to control a level of RF power and a duration for an ablation procedure. The controller is programmed to implement a process to estimate RF power dissipated in tissue (PT), including calculating power loss due to convective heat flow (PCONV) from the tissue through the electrode to the blood or the irrigation fluid to cool the electrode, and calculating the RF power dissipated in tissue (PT) by subtracting PCONV from PE.

Abstract: An ablation catheter system includes a tip assembly configured to provide ablation energy to tissue. The tip assembly includes an outer surface and a piezoelectric element is acoustically coupled to the outer surface of the tip assembly. The piezoelectric element is configured to cause the outer surface of the tip assembly to vibrate.

Abstract: An electrosurgery system includes a catheter including one or more active electrodes adapted to be positioned adjacent biological tissue at an in vivo treatment site in a patient and to deliver electrical energy to the biological tissue. The electrosurgery system further includes a dispersive electrode assembly including a conductive element having a first end and a second end. The dispersive electrode assembly is configured to surround a waist of the patient such that a first surface of the conductive element is in contact with the waist and the first end of the conductive element is adjacent the second end of the conductive element.

Abstract: An electrosurgery system includes a catheter including one or more active electrodes adapted to be positioned adjacent biological tissue at an in vivo treatment site in a patient and to deliver electrical energy to the biological tissue. The electrosurgery system further includes a dispersive electrode assembly including a conductive element having a first end and a second end. The dispersive electrode assembly is configured to surround a waist of the patient such that a first surface of the conductive element is in contact with the waist and the first end of the conductive element is adjacent the second end of the conductive element.