Adapting irrigation rate in radiofrequency (RF) ablation in response to contact-force variation
AssigneeBiosense Webster (Israel) Ltd.
InventorsAssaf Govari, Andres Claudio Altmann
Life of this patent
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Abstract
A method of body tissue ablation includes generating an ablation signal and providing the ablation signal to an ablation probe that is in contact with tissue. Irrigation fluid is delivered to the ablation probe, for applying the irrigation fluid in a vicinity of the tissue while the ablation signal is applied to the tissue. Signals are received from the ablation probe, which are indicative of an estimated instantaneous contact force that is exerted by the ablation probe against the tissue. A flow rate of the irrigation fluid is adapted responsively to the estimated instantaneous contact force.
Claims14
A method of body tissue ablation, the method comprising:
- generating an ablation signal and providing the ablation signal to an ablation probe that is in contact with tissue;
- delivering irrigation fluid to the ablation probe, for applying the irrigation fluid in a vicinity of the tissue while the ablation signal is applied to the tissue;
- receiving from the ablation probe signals indicative of an instantaneous contact force that is exerted by the ablation probe against the tissue;
- and
- adjusting the flow rate of the irrigation fluid responsively and iteratively to correspond to a determined increase or decrease in the instantaneous contact force and respective increase or decrease in heat applied to the tissue, wherein the irrigation flow rate is increased when it is determined that the instantaneous contact force has increased such that rate of heat removal from the tissue matches an increase in heat due to the increased instantaneous contact force and the irrigation flow rate is decreased when it is determined that the instantaneous contact force has decreased such that the rate of heat removal matches a decrease in heat due to the decreased instantaneous contact force;
- and
- determining, at each iteration, whether a preset amount of ablative energy was delivered, and stopping ablation in response to a determination that the preset amount of ablative energy was delivered.
A system for body tissue ablation, the system comprising:
- a generator, configured to generate an ablation signal and to provide the ablation signal to an ablation probe that is in contact with tissue;
- an irrigation module, configured to deliver irrigation fluid to the ablation probe, for applying the irrigation fluid in a vicinity of the tissue while the ablation signal is applied to the tissue;
- and
- a processor, configured to:
- receive from the ablation probe signals indicative of an instantaneous contact force that is exerted by the ablation probe against the tissue;
- and
- control the irrigation module to adjust a flow rate of the irrigation fluid responsively and iteratively to correspond to a determined increase or decrease in the instantaneous contact force and respective increase or decrease in heat applied to the tissue, wherein the irrigation flow rate is increased when it is determined that the instantaneous contact force has increased such that rate of heat removal from the tissue matches an increase in heat due to the increased instantaneous contact force and the irrigation flow rate is decreased when it is determined that the instantaneous contact force has decreased such that the rate of heat removal matches a decrease in heat due to the decreased instantaneous contact force;
- and
- determining, at each iteration, whether a preset amount of ablative energy was delivered, and stopping ablation in response to a determination that the preset amount of ablative energy was delivered.
Dependencies are inferred from the claim text.