High-voltage pulse ablation systems and methods
High-voltage pulses ablation systems and methods are used to ablate tissue and form lesions. A variety of different electrophysiology devices, such as catheters, surgical probes, and clamps, may be used to position one or more electrodes at a target location. Electrodes can be connected to power supply lines and, in some instances, the power to the electrodes can be controlled on an electrode-by-electrode basis. High-voltage pulse sequences provide a total amount of heating that is typically less than that which is observed with thermally-based radiofrequency energy ablation protocols.
1 . A method, comprising:
compressing cardiac tissue with a clamp comprising a first jaw on which a first electrode is disposed and a second jaw on which a second electrode is disposed;
applying at least one high voltage pulse regimen to the cardiac tissue with the first and second electrodes of the clamp to cause a dielectric breakdown of cellular membrane tissue to create a lesion in the cardiac tissue; and
applying another high voltage pulse regimen to the cardiac tissue with the clamp to produce a visible mark proximate the lesion, wherein a second width of one or more second voltage pulses of the other high voltage pulse regimen is greater than a first width of one or more first voltage pulses of the at least one high voltage pulse regimen, wherein the first voltage pulses comprise 1500-3000 volt pulses.
2 . The method of claim 1 , wherein a second magnitude of one or more second voltage pulses of the other high voltage pulse regimen is greater than a first magnitude of one or more first voltage pulses of the at least one high voltage pulse regimen.
3 . The method of claim 1 , wherein the cardiac tissue comprises a plurality of myocardial cells and the application of the at least one high voltage pulse regimen is sufficient to kill or cause irreversible damage to the plurality of myocardial cells.
4 . The method of claim 1 , wherein each of a plurality of pulses of the at least one high voltage pulse regimen has a duration of between about 0.01 milliseconds and about 0.1 milliseconds.
5 . The method of claim 1 , wherein a plurality of pulses of the at least one high voltage pulse regimen is delivered at a frequency comprising a pulse number within a range from about 5 to about 50 pulses discharged over a time interval within a range from about 1 to about 60 seconds.
6 . The method of claim 1 , wherein a plurality of pulses of the at least one high voltage pulse regimen has a voltage gradient above 500 volts/centimeter.
7 . The method of claim 1 , wherein the lesion comprises a substantially semicircular cross-section.
8 . A method, comprising:
placing a clamp at cardiac tissue, the clamp comprising at least a first electrode and a second electrode;
applying a plurality of 1500-3000 volt pulses at a frequency comprising a pulse number within a range from about 5 to about 50 pulses discharged over a time interval within a range from about 1 to about 60 seconds to form a lesion in the cardiac tissue; and
applying another plurality of pulses to the cardiac tissue with the clamp, wherein the other plurality of pulses is sufficient to form a visible mark on a surface of the cardiac tissue that corresponds to the lesion.
9 . The method of claim 8 , wherein each of the plurality of 1500-3000 volt pulses has a duration of between about 0.01 milliseconds and about 0.1 milliseconds.
10 . The method of claim 8 , wherein the plurality of 1500-3000 volt pulses has a voltage gradient above 500 volts/centimeter.
11 . The method of claim 8 , wherein the clamp comprises first and second jaws on which the first and second electrodes are disposed, the method further comprises compressing the cardiac tissue with the clamp before applying the plurality of 1500-3000 volt pulses, the cardiac tissue comprises a plurality of myocardial cells, and the application of the plurality of 1500-3000 volt pulses is sufficient to kill or irreversibly damage the myocardial cells between the first and second jaws.
12 . The method of claim 8 , wherein a second magnitude of one or more of the other plurality of pulses is greater than a first magnitude of one or more of the plurality of 1500-3000 volt pulses.
13 . The method of claim 8 , wherein a second width of one or more of the other plurality of pulses is greater than a first width of one or more of the plurality of 1500-3000 volt pulses.
14 . The method of claim 8 , wherein the plurality of 1500-3000 volt pulses is sufficient to ablate the cardiac tissue to a depth between about 5 millimeters and about 10 millimeters and the lesion comprises a substantially semicircular cross-section.
15 . A method, comprising: placing a clamp at cardiac tissue, the clamp comprising at least a first electrode and a second electrode; applying a plurality of first pulses having a voltage gradient above 500 volts/centimeter at a frequency comprising a pulse number within a range from about 5 to about 50 pulses discharged over a time interval within a range from about 1 to about 60 seconds to form a lesion in the cardiac tissue; and applying a plurality of second pulses to the cardiac tissue with the clamp, wherein a second magnitude of one or more of the plurality second of pulses is greater than a first magnitude of one or more of the plurality of first pulses, wherein the plurality of second pulses is sufficient to form a visible mark on a surface of the cardiac tissue that corresponds to the lesion, wherein the visible mark is formed via radiofrequency energy.
16 . The method of claim 15 , wherein each of the plurality of first pulses is of 1500-3000 volts.
17 . The method of claim 15 , wherein each of the plurality of first pulses has a duration of between about 0.01 milliseconds and about 0.1 milliseconds.