Cardiac pulsed field ablation
A method for ablating tissue by applying at least one pulse train of pulsed-field energy. The method includes delivering a pulse train of energy having a predetermined frequency to cardiac tissue, the pulse train including at least 60 pulses, an inter-phase delay between 0 μs and 5 μs, an inter-pulse delay of at least 5 μs, and a pulse width of 5 μs.
1. A method of ablating cardiac tissue, the method comprising:
delivering a pulse train of energy having a predetermined frequency to cardiac tissue, the pulse train including:
at least 60 pulses;
an inter-phase delay between 0 μs and 5 μs;
an inter-pulse delay of 800 μs; and
a pulse width of between 1 μs and 15 μs.
2. The method of claim 1 , wherein the pulse train of energy has a voltage between 300V and 4000V and wherein the predetermined frequency is approximately 1 kHz.
3. The method of claim 1 , wherein the pulse train of energy is initiated between 70 ms and 100 ms after onset of an R-wave.
4. The method of claim 1 , wherein the pulse train of energy is gated to initiate the delivery of the pulse train radiofrequency energy at the end of an S-wave.
5. The method of claim 1 , wherein the pulse train of energy may be delivered to a plurality of cardiac treatment sites, the method further comprising:
delivering the pulse train of energy four times at each of the plurality of treatment sites.
6. The method of claim 1 , further including positioning a medical device proximate the cardiac tissue to be treated, the medical device including a distal electrode array having a plurality of electrodes, each electrode having a polarity that is different than each adjacent electrode, and where the pulse train of energy is delivered from the distal electrode array.
7. The method of claim 6 , wherein the pulse train of energy is delivered in bipolar mode.
8. The method of claim 7 , wherein the pulse train of energy includes biphasic pulses.
9. The method of claim 8 , wherein the biphasic pulses are delivered at a plurality of voltage amplitudes.
10. The method of claim 9 , wherein the plurality of voltage amplitudes includes a first amplitude and a second amplitude, the second amplitude being higher than the first amplitude, and wherein the biphasic pulses delivered at the first amplitude are delivered at a higher frequency than the biphasic pulses delivered at the second amplitude.
11. A system for ablating cardiac tissue, the system comprising:
a generator configured to deliver at least one pulse train of energy at a predetermined frequency, each pulse train of energy including:
at least 60 pulses;
an inter-phase delay of between 0 μs and 5 μs;
an inter-pulse delay of 800 μs;
a pulse width of between 1 μs and 15 μs;
a voltage between 300V and 4000V; and
the generator including a processor configured to control the delivery of the at least one pulse train based on a measured patient parameter.
12. The system of claim 11 , further including a medical device in electrical communication with the generator, the medical device having a plurality of electrodes, each electrode having a polarity that is different than each adjacent electrode, the at least one pulse train of energy being delivered in bipolar mode from the plurality of electrodes.
13. The system of claim 12 , wherein the pulse train of energy includes biphasic pulses, and wherein the generator is configured to deliver the biphasic pulses at a plurality of voltage amplitudes.
14. The system of claim 12 , further including ECG electrodes couplable to the generator and in communication with the processor, the ECG electrodes being configured to measure electrical waveforms generated by a patient's heart, and wherein the measured patient parameter is measured by the ECG electrodes.
15. The system of claim 14 , wherein the measured patient parameter includes the detection of the onset of an R-wave, and wherein the generator is configured to initiate the pulse train of energy between 70 ms and 100 ms after onset of an R-wave measured.
16. The system of claim 14 , wherein the measured patient parameter includes the detection of the onset of an S-wave, and wherein the pulse train of energy is gated by the processor to initiate the delivery of the pulse train of energy at the end of an S-wave.
17. The system of claim 14 , wherein the generator is configured to initiate the pulse train of energy after a predetermined delay following the delivery of a 5-100V, monophasic pacing pulse from the plurality of electrodes, the pacing pulse being 0.5 ms in duration.
18. The system of claim 17 , the monophasic pacing pulse is the last pulse in a series of pacing pulses delivered by the generator.
19. The system of claim 17 , wherein the plurality of voltage amplitudes includes a first amplitude and a second amplitude, the second amplitude being higher than the first amplitude, and wherein the biphasic pulses delivered at the first amplitude are delivered at a higher frequency than the biphasic pulses delivered at the second amplitude.
20. The system of claim 11 , wherein the predetermined frequency is approximately 1 kHz.
21. A method of ablating cardiac tissue, the method comprising:
positioning a medical device proximate cardiac tissue to be treated, the medical device having a plurality of electrodes, each electrode having a polarity that is different than each adjacent electrode;
measuring an electrocardiogram from ECG electrodes, the measured electrocardiogram including a QRS waveform; and
delivering between adjacent electrodes of the plurality of electrodes, a biphasic pulse train of energy, at a frequency of approximately 1 kHz, to the cardiac tissue to be treated between 70 ms and 100 ms after onset of an R-wave measured by the ECG electrodes, the pulse train of energy including a plurality of voltage amplitudes, and:
at least 60 pulses;
an inter-phase delay between 0 μs and 5 μs;
an inter-pulse delay of 800 μs;
a pulse width of between 1 μs and 15 μs; and
a voltage between 300V and 4000V;
the plurality of voltage amplitudes including a first amplitude and a second amplitude, the second amplitude being higher than the first amplitude, the biphasic pulses delivered at the first amplitude are delivered at a higher frequency than the biphasic pulses delivered at the second amplitude.