Methods and systems to combine RF ablation therapy with device navigation
Methods and systems for combining ablation therapy with navigation of the ablation device. An ablation system may be configured for use with one of two methods to prevent loss of navigation signals during ablation energy delivery. In the first method, ablation energy signals are filtered from the navigation signal. In the second method, the delivery of ablation energy is sequenced with the delivery of navigation energy such that ablation energy and navigation energy are not delivered at the same time and navigation signals received by the system are time-division multiplexed to reconstruct the navigation signals and determine a location of the device within the patient.
1 . A method of determining a location of a treatment device during an ablation procedure within a patient, the method comprising:
delivering pulsed electric field ablation energy from an energy generator to an ablation electrode of the treatment device to an area of tissue;
delivering navigation energy to a plurality of external patch electrodes from a plurality of navigation energy sources, the navigation energy delivered by each of the plurality of navigation energy sources being a same frequency; and
filtering the delivery of the ablation energy and the delivery of the navigation energy using a first filter that is applied to an input of the navigation energy sources, the first filter allowing navigation energy to pass between the treatment device and the plurality of navigation energy sources while presenting a high impedance and preventing the ablation energy from entering the plurality of external patch electrodes.
2 . The method of claim 1 , wherein the plurality of navigation energy sources are three alternating current energy sources that deliver energy at three separate frequencies.
3 . The method of claim 2 , wherein the three separate frequencies are each at least 30 kHz, the three separate frequencies being delivered to the external patch electrodes.
4 . The method of claim 1 , wherein the first filter is a band-reject filter that matches the frequency of the delivered ablation energy.
5 . The method of claim 4 , wherein the band-reject filter matches at least one of the following frequencies 460.8 kHz and 100 kHz.
6 . The method of claim 1 , further comprising:
filtering the delivery of ablation energy from the energy generator with a second filter that is at the energy generator to prevent the ablation energy from interfering with the navigation energy.
7 . The method of claim 6 , wherein the second filter is a band-reject filter that matches the frequency of the delivered navigation energy.
8 . The method of claim 1 , further comprising:
transmitting a plurality of voltage signals from a mapping electrode of the treatment device to a processing unit, the processing unit time-division multiplexing the voltage signals, wherein the processing unit time-division multiplexes the voltage signals in each of a first plane, a second plane, and a third plane; and
determining a location of the treatment device within a patient based on the time-division multiplexed voltage signals.
9 . The method of claim 1 , wherein the navigation energy is delivered by a navigation system, further comprising protecting the navigation system from ablation energy with a shunt.
10 . The method of claim 9 , wherein the shunt is located between the first filter and the navigation system.
11 . The method of claim 10 , further comprising:
filtering the delivery of ablation energy from the energy generator with a second filter that is at the energy generator to prevent the ablation energy from interfering with the navigation energy.
12 . The method of claim 1 , wherein:
the energy generator is an ablation energy generator; and
each of the plurality of navigation energy sources are within a navigation energy generator.