Asymmetric balanced waveform for AC cardiac irreversible electroporation

A method of applying irreversible electroporation to a target tissue, comprising:

• sending an asymmetric balanced waveform from an electroporation generator to a medical device comprising an electrode assembly having a plurality of electrode elements, wherein the electroporation generator is configured to receive a signal for identifying which pairs of the plurality of electrode elements have electrical characteristics indicative of contact with the target tissue when the target tissue is energized with an excitation signal, and wherein the electroporation generator is configured and to use an electroporation energization strategy to energize at least one of the pairs of the plurality of electrode elements identified as having contact with the target tissue with the asymmetric balanced waveform,
• wherein the asymmetric balanced waveform comprises a first positive phase and a first negative phase, wherein the first positive phase comprises a first current and a first time and wherein the first negative phase comprises a second current and a second time,
• wherein the first current is greater than the second current and wherein the second time is greater than the first time, and
• wherein the asymmetric balanced waveform is configured to enhance electroporation in a non-linear manner while also minimizing neurostimulation of the target tissue, and wherein the asymmetric balanced waveform is further configured to provide a production rate of new pores that is enhanced in a non-linear manner when a time duration of a transmembrane voltage is reduced by a factor 2 and an amplitude of the transmembrane voltage is multiplied by a factor 2.

An electroporation therapy system, comprising:

• a medical device comprising a plurality of electrode elements;
• and
• an electroporation generator, wherein the electroporation generator is configured to output an asymmetric balanced waveform to the plurality of electrode elements, and wherein the electroporation generator is further configured to receive a signal for identifying which pairs of the plurality of electrode elements have electrical characteristics indicative of contact with a target tissue when the target tissue is energized with an excitation signal, and wherein the electroporation generator is configured to use an electroporation energization strategy to energize at least one of the pairs of the plurality of electrode elements identified as having contact with the target tissue with the asymmetric balanced waveform,
• wherein the asymmetric balanced waveform comprises a first positive phase and a first negative phase, wherein the first positive phase comprises a first current and a first time and wherein the first negative phase comprises a second current and a second time,
• wherein the first current is greater than the second current and wherein the second time is greater than the first time, and
• wherein the asymmetric balanced waveform configured to irreversibly electroporate the target tissue, and wherein the electroporation generator is configured to determine whether neurostimulation will occur using the equation
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