# US 10,441,354 B2 · Temperature controlled short duration ablation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,441,354 B2 - Document ID: US10441354B2 - Status: Granted - Kind: B2 - Application number: 15/179,167 - Filed: 2016-06-10 - Published: 2017-07-27 - Granted: 2019-10-15 - Earliest claimed: 2016-01-25 - Assignees: Biosense Webster (Israel) Ltd. - Applicants: Biosense Webster (Israel) Ltd. - Inventors: Assaf Govari; Yaron Ephrath; Andres Claudio Altmann; Israel Zilberman - Web page: https://patentgrep.com/patent/US10441354B2 ## CPC - A61B 18/1492: {having a flexible, catheter-like structure, e.g. for heart ablation (A61B18/1477 takes precedence)} - A61B 2018/00029: {open} - A61B 2018/00351: {Heart} - A61B 2018/00577: {Ablation} - A61B 2018/00666: {using a threshold value} - A61B 2018/00678: {upper} - A61B 2018/00702: {Power or energy} - A61B 2018/00791: {Temperature} - A61B 2018/00875: {Resistance or impedance} - A61B 2090/065: {for measuring contact or contact pressure} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A method, including selecting a first maximum radiofrequency (RF) power to be delivered by an electrode within a range of 70 W-100 W, and selecting a second maximum RF power to be delivered by the electrode within a range of 20 W-60 W. The method also includes selecting an allowable force on the electrode within a range of 5 g-50 g, selecting a maximum allowable temperature, of tissue to be ablated, within a range of 55° C.-65° C., and selecting an irrigation rate for providing irrigation fluid to the electrode within a range of 8-45 ml/min. The method further includes performing an ablation of tissue using the selected values by initially using the first power, switching to the second power after a predefined time between 3 s and 6 s, and terminating the ablation after a total time for the ablation between 10 s and 20 s. ## Claims ### Claim 1 A method, comprising: defining a preset impedance value I; performing an ablation procedure on biological tissue using radiofrequency (RF) power; measuring an impedance IT-1 to the RF power during the ablation procedure at time (T−1); measuring an impedance IT to the RF power during the ablation procedure at time (T); and when a difference between impedance IT and IT-1 exceeds the preset impedance value I, halting supply of the RF power to the tissue. ### Claim 2 (depends on 1) The method of claim 1, wherein the preset impedance value I is 7 ohms. ### Claim 3 (depends on 1) The method of claim 1, further comprising measuring temperature of the tissue when the difference between impedance IT-1 and IT is not greater than the preset impedance value I. ### Claim 4 (depends on 3) The method of claim 3, wherein the measuring temperature of the tissue occurs at a frequency of at least 30 Hz. ### Claim 5 (depends on 4) The method of claim 4, wherein the reducing supply of the RF power includes reducing supply of the RF power by a range between about 5% 95%. ### Claim 6 (depends on 1) The method of claim 1, further comprising reducing supply of the RF power to the tissue when a measured temperature of the tissue reaches or exceeds a preset maximum temperature value. ### Claim 7 Apparatus, comprising: a power control module configured to perform an ablation procedure on biological tissue using radiofrequency (RF) power; and a processor configured to: measure an impedance IT-1 to the RF power during the procedure at time (T−1); measure an impedance IT to the RF power during the procedure at time (T); and when difference between impedance IT-1 and IT exceeds a preset impedance value, halt supply of the RF power to the tissue. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein the preset impedance value is 7 ohms. ### Claim 9 (depends on 7) The apparatus of claim 7, wherein the processor is configured to measure temperature of the tissue when the difference between impedance IT-1 and IT is not greater than the preset impedance value. ### Claim 10 (depends on 9) The method of claim 9, wherein the processor is configured to measure temperature of the tissue at a frequency of at least 30 Hz. ### Claim 11 (depends on 7) The apparatus of claim 7, wherein the processor is configured to reduce supply of the RF power to the tissue when a measured temperature of the tissue reaches or exceeds a preset maximum temperature value. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the processor is configured to reduce supply of the RF by a range between about 5% 95%. ### Claim 13 A method, comprising: defining a preset impedance value I; performing an ablation procedure on biological tissue using radiofrequency (RF) power at a power up to about 100 W with a duration of no greater than 10 seconds; measuring an impedance IT-1 to the RF power during the ablation procedure at time (T−1); measuring an impedance IT to the RF power during the ablation procedure at time (T); and when a difference between impedance IT and IT-1 exceeds the preset impedance value I, halting supply of the RF power to the tissue. ### Claim 14 (depends on 13) The method of claim 13, wherein the impedances IT-1 and IT are measured at a rate of about every 500 ms. ### Claim 15 Apparatus, comprising: a power control module configured to perform an ablation procedure on biological tissue using radiofrequency (RF) power; and a processor configured to: perform the ablation procedure on the biological tissue using the radiofrequency (RF) power at a power up to about 100 W with a duration of no greater than 10 seconds; measure an impedance IT-1 to the RF power during the procedure at time (T−1); measure an impedance IT to the RF power during the procedure at time (T); and when difference between impedance IT-1 and IT exceeds a preset impedance value, halt supply of the RF power to the tissue. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the processor is configured to measure the impedances IT-1 and IT at a rate of about every 500 ms.